Exploration of the relationship between the height of the popliteal artery injury plane and the risk of amputation

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Methods A retrospective analysis was conducted on ninety-four patients who underwent PAI; these patients were divided into an amputation group (n = 26) and a nonamputation group (n = 68) on the basis of whether limb preservation was successful. The data were reconstructed from computed tomography angiography (CTA) of the patients’ lower limbs and measured via AW Volume Share 5 software. The height of the popliteal artery injury surface was quantified as follows: "L" was defined as the distance from the origin of the descending genicular artery of the contralateral limb to the origin of the anterior tibial artery; "S" was defined as the distance from the origin of the descending genicular artery of the affected limb to the blood flow interruption site; and "R" was defined as the ratio of S to L (S/L). The risk factors for amputation in patients with PAI were also analysed. Results Univariate and multivariate logistic regression analyses revealed that R (odds ratio [ OR ] = 0.876, P = 0.006,95% CI :0.797–0.963), S ( OR = 0.792, P = 0.166,95% CI :0.570–1.102), ischemic time ( OR = 1.195, P = 0.017,95% CI :1.032–1.383), and compartment syndrome ( OR = 5.509, P = 0.055,95% CI :0.967–31.376) were independent risk factors for amputation in patients with PAI. The receiver operating characteristic (ROC) curve revealed that the AUC values were 0.887 ( P < 0.000, 95% CI : 0.805–0.943) and 0.775 ( P < 0.000, 95% CI : 0.677–0.854) for R and S, respectively. The diagnostic efficiency was highest when the diagnostic threshold values were 0.573 and 11.3 cm, for R and S, respectively. Moreover, the AUC R was greater than the AUC S ( Z = 2.403, P = 0.0162). Conclusion The height of the PAI plane is an independent risk factor for amputation in patients with PAI. Greater planes of vascular injury result in greater risk of amputation. R is better than S in the diagnosis of amputation risk in patients with PAI. Popliteal artery Damage plane Risk of amputation Trauma Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 1. Background Popliteal artery injury (PAI) is a refractory lower limb injury [ 1 ] and one of the most threatening peripheral vascular injuries [ 2 , 3 ]. When accompanied by severe soft tissue injury or limb ischaemia, the risk of amputation is usually greater [ 4 – 7 ]. It is generally believed that 6–8 h after vascular injury is the golden time to rescue the limbs. However, in some patients whose ischemic time is far longer than 8 h (even up to 48 h), surgery can still successfully save the affected limb. Reviewing the imaging data of these patients after injury, computed tomography angiography (CTA) of the lower limb usually reveals a lower height of the PAI. PAI can be confirmed by physical examination combined with imaging data [ 8 ]. However, further assessment of the risk of amputation with similar soft tissue injuries and ischemic times is challenging. At present, there are few reports about the risk of amputation on the basis of the height of the PAI. Therefore, the present study aimed to compare and analyse the clinical data of PAI patients and further explore the importance of injury height for amputation risk assessment. 2. Methods 2.1 General clinical characteristics of patients The general clinical data of 94 patients with popliteal artery injury and knee injury admitted to the 904th Hospital of the PLA Joint Logistics Support Force from January 2019 to December 2024 were retrospectively analysed. The clinical data included age, sex, height, weight, body mass index (BMI), injury site (left and right), injury type, fracture, ligament, vein injury, injury score (ais-iss) [ 14 ], limb injury severity score (MESS), and ischemic time of the affected limb. The imaging parameters were defined as follows: "L" was defined as the distance from the origin of the descending genicular artery of the contralateral limb to the origin of the anterior tibial artery; "S" was defined as the distance from the origin of the descending genicular artery of the affected limb to the blood flow interruption site; and "R" was defined as the ratio of S to L (S/L). The inclusion criteria were as follows: 1) patients with a clear history of acute lower limb trauma; 2) patients with unilateral popliteal artery injury and knee joint trauma; 3) patients who were able tolerate surgery. The exclusion criteria were as follows: 1) patients with crush injury, blast injury, firearm injury, or other injuries involving the muscles of the affected limb; 2) patients without the possibility of limb salvage according to the mangled extreme severity score (MESS) [ 9 – 10 ] were; 3) patients with severe injuries to the head, neck, chest, abdomen, and other parts, as well as patients who received life-threatening rescue and unconditional limb salvage surgery for popliteal artery injury; 4) patients whose CTA imaging data were incomplete; And 5) patients with vasculitis, vascular occlusion ,and other vascular diseases. The study protocol was approved by the Ethical Committee of the 904th Hospital of the Joint Service Support Force of the Chinese People's Liberation Army. Owing to the retrospective nature of the study, the 904th Hospital of the Joint Service Support Force of the Chinese People's Liberation Army waived the need to obtain informed consent. 2.2 Imaging diagnosis and grouping Patients were divided into an amputation group and a nonamputation group according to whether limb salvage was successful. Preoperative physical examination and CTA of the affected limb were performed to identify the site of vascular injury (Fig. 1 ). Three-dimensional reconstruction and measurement were performed on the imaging data of the included patients via AW Volume 5 as follows: the distance L from the origin of the descending knee artery to the origin of the anterior tibial artery in the healthy limb and the distance S from the starting site of blood flow interruption in the affected limb to the origin of the descending knee artery (Fig. 2 ). The length L of the popliteal artery in the affected limb could not be measured due to blood flow interruption caused by injury. In addition, on the basis of the literature, there is no statistically significant difference in the length of the popliteal artery in both lower limbs of the same patient [ 11 – 12 ]). 2.3 Surgical methods and postoperative management Traditional surgical treatment was used for 94 patients with popliteal artery injury in the first stage. After initial debridement, external fixation or internal fixation with steel plates and screws were used to correct fractures and dislocations around the knee joint, ensuring that the fractures were aligned and maintained a stable position of the knee joint (Fig. 3 ). The wound was cut by making an S-shaped incision of approximately 30 cm in the popliteal area, and the skin and subcutaneous tissue were cut layer by layer to create deep fascia after changing the prone position. Damage to the tibial nerve and common peroneal nerve was explored, and the type of popliteal artery injury was determined (Fig. 4 ). Inactivated soft tissue and blood clots were thoroughly removed, and the damaged blood vessels were trimmed and removed under the microscope to smooth the popliteal artery intima (Fig. 5 – 6 ). If the length of the injury exceeded 3 cm, the great saphenous vein was taken from the patient's healthy side for vascular transplantation, and a 9–0 noninvasive suture line was used for two-point bridge anastomosis. After the blood supply was rebuilt, the tourniquet was loosened, and it was determined whether the blood vessels were unobstructed. If there was blood leakage at the anastomotic site, the activity of muscle and soft tissue was visually assessed, and muscle tissue with a pale colour and suspicious necrosis was removed to further repair damaged nerves and tendons. If high calf tension was found, an osteofascial incision was performed for decompression. For PAI patients without combined fractures, uncomplicated popliteal vein embolization, thrombectomy, vascular exploration, vascular repair, and contralateral great saphenous vein transplantation were performed through the posterior popliteal fossa approach. After surgery, the affected limb was maintained in a temperature-appropriate and smoke-free environment, and the knee joint was maintained in a stable position of 20° − 30° flexion. Attention was given to the colour, temperature, and vascular pulsation of the affected limb, and various biochemical indicators were detected in a timely manner. Anticoagulation, spasmolysis, anti-infection, and nutritional support were provided on the basis of test indicators to prevent acute renal failure and compartment syndrome [ 13 ]. 2.4 Statistical analysis Statistical analysis was conducted via SPSS 26.0 and MedCalc 19.3 software. The quantitative data are expressed as the means ± standard deviations, whereas the count data are expressed as percentages. A t test was used to analyse intergroup differences in econometric data that met a normal distribution. A rank sum test was used for econometric data that did not meet a normal distribution. Counting data were subjected to the chi-square test. All variables were analysed by univariate logistic regression analysis. The significant indicators in the univariate logistic regression analysis results were diagnosed as collinear (variance expansion factor < 10). After the collinearity indicators were excluded, the significant variables were included in the multivariate logistic regression analysis, and the odds ratios ( OR s) and 95% confidence interval ( CI ) were further calculated. Receiver characteristic curves for S and R were generated, and the diagnostic value of the injury plane on amputation risk was evaluated. The area under the curve ( AUC ) values and 95% CIs were calculated, and the AUC S and AUC R between the two groups were compared via the DeLong test ( P < 0.05 indicates a statistically significant difference). The distributions of representative values of S and R in the injury plane for injury type, combined fracture, and combined compartment syndrome were compared in PAI patients. Correlation analysis was conducted to investigate the correlation between representative R and S values of the injury plane and the ischemic time in PAI patients. Two-tailed or two-sided tests were used, and statistically significant differences were defined as P < 0.05. 3. Results 3.1 Comparison of baseline data between the two patient groups A total of 94 patients were included in this study, including 89 males and 5 females, aged 41 (36,45) years. The causes of injury were as follows: 51 cases of traffic accident injury, 34 cases of high-altitude falling injury, 5 cases of cutting injury, 3 cases of puncture injury, and 1 case of rope strangulation injury. There were 58 cases of closed injury and 36 cases of open injury. There were 47 cases of simple knee dislocation and 61 cases of combined fractures, including 18 cases of simple tibial plateau fractures (11 cases of Schatzker type Ⅰ fractures and 7 cases of Schatzker type Ⅳ fractures) and 7 cases of fractures combined with dislocation. There were 21 cases of simple femoral intercondylar or supracondylar fractures and 15 cases of fractures combined with dislocation (9 cases of Hohl Moore-type fractures and 6 cases of type III fractures). The above patients were divided into an amputation group (n = 26) and a nonamputation group (n = 68) according to whether limb salvage was successful. There were no deaths, and the amputation rate was 27.7%. Among them, there were 7 cases of delayed amputation due to infection and necrosis of limb wounds after amputation and 4 cases of delayed amputation due to osteomyelitis. Vascular crisis occurred within 1–3 days after the operation, and 8 cases were amputated after emergency vascular exploration. Two cases involved life-threatening amputation, owing to haemorrhagic shock due to aneurysm rupture, and 5 cases were amputated due to severe renal failure. Among the successful limb salvage patients, 16 experienced foot drop and recovered after secondary Achilles tendon lengthening surgery. Among the 61 patients with concurrent fractures of different parts, two patients experienced delayed fracture healing 8 months after surgery and underwent secondary bone grafting and plate internal fixation before healing. The remaining patients all experienced primary healing. The present study compared the severity of limb injuries (MESS score), ischemic time, age, sex, body mass index, injury type, systemic injury score (AIS-ISS score), inner diameter D (mm) of the affected limb blood flow interruption site, combined fractures, and combined fascial compartment syndrome in the two groups of patients. Baseline data, such as combined ligament injuries, were subjected to intergroup difference tests (Table 1 ). There were no significant differences in the baseline data, such as ischaemia time and severity of limb injury (MESS score), between the two groups of patients ( P < 0.05). After removing the aforementioned confounding factors as much as possible, the impact of the injury plan on the risk of amputation in PAI patients was explored, which revealed a significant difference in the injury plane (S, R) between the two groups ( t s =4.500, P s <0.00; t R =6.974, P R <0.00). Table 1 Comparison of baseline data and main observation indicators between the two groups group Amputation group Non-Amputation group Test value P Age( year) 41.46 ± 7.28 39.75 ± 6.82 t =-1.069 0.288 BMI(kg∙m-2) 24.64 ± 2.29 24.90 ± 3.54 t = 0.343 0.305 Ischemic time(h) 15.46 ± 6.00 7.50 ± 3.33 t =-8.177 < 0.001 AIS-ISSscore 12.24 ± 3.10 12.74 ± 3.89 t = 0.581 0.563 MESS-score 6.23 ± 1.42 5.75 ± 1.95 t =-1.144 0.255 Gender[number(%)] χ2 = 0.402 0.614 male 24(92.3) 65(95.6) female 2(7.7) 3(4.4) Part[number(%)] χ2 = 2.462 0.164 left 15(57.7) 27(39.7) right 11(42.3) 41(60.3) Type of injury[number(%)] χ2 = 5.723 0.022 blunt 23(88.5) 43(63.2) sharp 3(11.5) 25(36.8) Open wound[number(%)] χ2 = 0.000 0.984 open 10(38.5) 26(38.2) closed 16(61.5) 42(61.8) Combined fracture[number(%)] χ2 = 3.976 0.055 with 21(80.8) 40(58.8) without 5(19.2) 28(41.2) Types of vascular injury[number(%)] χ2 = 0.322 0.643 rupture 12(46.2) 27(39.7) no rupture 14(53.8) 41(60.3) Combined compartment syndrome[number(%)] χ2 = 19.552 < 0.001 with 15(57.7) 9(13.2) without 11(42.3) 59(86.8) Combined ligament injury[number(%)] χ2 = 0.862 0.478 with 8(30.8) 28(41.2) without 18(69.2) 40(58.8) Combined vein injury[number(%)] χ2 = 0.632 0.493 with 15(57.7) 33(48.5) without 11(42.3) 35(51.5) D(mm) 6.76 ± 2.30 7.02 ± 1.68 t = 0.621 0.536 S(cm) 8.77 ± 2.41 12.02 ± 3.37 t = 4.500 < 0.001 L(cm) 18.77 ± 4.98 18.51 ± 4.75 t =-0.237 0.813 R = S/L(%) 47.51 ± 8.67 65.49 ± 11.98 t = 6.974 < 0.001 Note: D represents the inner diameter of the affected limb popliteal artery blood flow interruption point (mm); S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; L represents the distance from the opening of the descending genicular artery on the healthy limb to the origin of the anterior tibial artery (cm); R is the ratio of S to L (%). 3.2 Analysis of amputation risk factors Univariate logistic regression analysis was performed for each variable (Table 2 ), which revealed significant differences ( P < 0.05) in injury type, ischemic time, combined fractures, combined fascial compartment syndrome, S, and R. Collinearity diagnostic analysis of the above indicators revealed that there was no collinearity among the indicators (variance inflation factor < 10). After these six variables were incorporated, further multivariate logistic regression analysis was performed (Table 3 ). ischemic time ( OR = 1.195, P = 0.017,95% CI :1.032–1.383),concomitant fascial compartment syndrome ( OR = 5.509, P = 0.055,95% CI :0.967–31.376), distance S from the site of blood flow interruption in the affected limb to the opening of the descending knee artery ( OR = 0.792, P = 0.166,95% CI :0.570–1.102),, and the ratio of injury distance S to the distance L from the opening of the anterior tibial artery in the healthy limb ( OR = 0.876, P = 0.006,95% CI :0.797–0.963)were independent risk factors for amputation in patients with PAI. Table 2 Univariate logistic regression results variable B P OR 95%CI Type of injury 1.495 0.024 4.457 1.215–16.359 Ischemic time 0.312 < 0.001 1.367 1.211–1.543 Combined compartment syndrome 2.190 < 0.001 8.939 3.136–25.482 Combined fracture 1.078 0.052 2.940 0.990–8.730 S -0.334 < 0.001 0.716 0.602–0.852 R -0.170 < 0.001 0.844 0.784–0.909 Note: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; R is the ratio of S to L (%). Table 3 Multivariate logistic regression results variable B P OR 95%CI Type of injury 1.727 0.078 5.622 0.822–38.438 Ischemic time 0.178 0.017 1.195 1.032–1.383 Combined compartment syndrome 1.706 0.055 5.509 0.967–31.376 Combined fracture 1.613 0.106 5.018 0.709–35.530 S -0.233 0.166 0.792 0.570–1.102 R -0.132 0.006 0.876 0.797–0.963 Note: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; R is the ratio of S to L (%). 3.3 Correlation analysis between injury plane and ischemic time, injury type, combined fractures, and combined compartment syndrome of bone and fascia The correlations between a series of clinical features, such as ischaemia time, injury type, combined fractures, and combined fascial compartment syndrome, in PAI patients and the S and R preoperative injury planes were evaluated (Table 4 , Figs. 7 – 9 ). A t test was performed between groups before the correlation analysis was conducted, which revealed the following results: S ( t t =0.328, P t =0.744; t F =0.753, P F =0.453; t O =1.874, P O =0.064) and R ( t t =0.508, P t =0.613; t F =1.480, P F =0.142; t O =3.148, P O =0.002). Pearson correlation analysis was performed on the S and R injury planes and the ischemic time, which revealed that r R =-0.487, P R <0.001, r S =-0.369, and P S <0.001. Table 4 Comparison of the distributions of injury planes S and R according to injury type, combined fracture, and combined bone compartment syndrome N S(cm) Test value P N R = S/L(%) Test value P Damage type Blunt injury 66 11.05 ± 3.25 t = 0.328 0.744 66 60.05 ± 14.20 t = 0.508 0.613 Sharp injury 28 11.30 ± 3.93 28 61.63 ± 12.80 Fracture Combined fracture 61 10.93 ± 3.25 t = 0.753 0.453 61 58.98 ± 14.37 t = 1.480 0.142 Non-fracture 33 11.49 ± 3.81 33 63.35 ± 12.22 OFS Combined-OFS 24 10.00 ± 3.65 t = 1.874 0.064 24 53.23 ± 11.93 t = 3.148 0.002 Non-OFS 70 11.51 ± 3.31 70 63.01 ± 13.51 Note: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; L represents the distance from the opening of the descending genicular artery on the healthy limb to the origin of the anterior tibial artery (cm); R is the ratio of S to L (%), and OFS represents compartment syndrome of the bone fascia. 3.4 Predictive efficacy of different injury planes on amputation risk in PAI patients Evaluation of the diagnostic efficiency of the injury plane in predicting amputation risk through area under the curve ( AUC ) values of S and R (Fig. 10 ) demonstrated that the area under the curve values of R and S were 0.887 ( P < 0.000, 95% CI : 0.805–0.943) and 0.775 (P AUC S ( Z = 2.403, P = 0.0162). The diagnostic efficiency was highest when the R and S diagnostic thresholds were 0.573 and 11.3 cm, respectively. 4. Discussion Some scholars believe that the amputation rate of PAI patients is related to their preserved collateral circulation supply [ 19 – 20 ]. When a patient experiences popliteal artery injury, the amount of adequate collateral circulation generated is determined by the blood flow interruption plane at the time of injury. When the plane of vascular injury in the affected limb is low, the central collateral circulation is not disrupted or blocked, and blood flow can bypass the interruption site of the main popliteal artery, providing compensatory blood for the distal ischemic and hypoxic limbs. To a certain extent, this can reduce the pathological substances produced by anaerobic metabolism after ischaemia, delay ischemic soft tissue necrosis, and minimize the degree of limb injury, thereby reducing the risk of amputation for patients. In the present study, univariate logistic regression analysis was performed on each variable, and the distance S from the site of blood flow interruption in the affected limb to the origin of the descending genicular artery (OR = 0.716, P < 0.001,95% CI:0.602–0.852,Tables 2 ), was determined. Multivariate logistic regression results showed that the ratio R(OR = 0.876, P = 0.006,95% CI:0.797–0.963,Tables 3 ) between the injury distance S and the distance L from the origin of the descending genicular artery to the origin of the anterior tibial artery in the healthy limb suggested that the height of the injury plane further affects or represents the number of collateral branches retained after injury, which in turn affects the amputation rate. In addition, the receiver operating characteristic ( ROC ) curves of S and R were used to evaluate the diagnostic efficiency of the injury plane in predicting amputation risk (Fig. 10 ), which indicated that the AUC values of R and S were 0.887 ( P < 0.000, 95% CI : 0.805–0.943) and 0.775 ( P < 0.000, 95% CI :0.677–0.854),respectively, representing statistically significant differences. Therefore, in cases of similar injuries and ischemic times, the plane of injury may be another critical factor in assessing the risk of amputation in affected limbs. Currently, few studies support the view that the plane of injury can affect the risk of amputation in PAI patients. When the height of the popliteal artery injury plane is quantified, the essence of S and R represents the location of blood flow interruption. The amount of sufficient collateral circulation retained in PAI patients after injury depends on the location of blood flow interruption. Greater S and R values result in lower planes of injury, ultimately preserving more collateral circulation in the affected limb. Greater abundance of collateral compensatory blood supply in the distal ischemic limb results in fewer pathological substances produced by anaerobic metabolism per unit time and milder degree of soft tissue ischaemia and hypoxia. Thus, PAI patients with a low degree of injury face a lower risk of amputation under the premise of a similar degree of limb soft tissue injury and similar ischemic times. This conclusion is consistent with some statistical analysis results in the present study. A t test comparison between the S and R scores of amputated and nonamputated patients revealed significant differences in S and R between the two groups( t s =4.500, P s <0.00; t R =6.974, P R <0.00). The postoperative amputation rate of patients with high injury planes was much greater than that of patients with low injury planes. The ischemic time of the affected limb after popliteal artery injury is usually considered the main traditional factor affecting the risk of amputation. Longer ischemic times result in greater amounts of waste accumulated after anaerobic metabolism of the tissue, more severe degrees of muscle injury, and greater risk of amputation. A previous study on popliteal artery injury combined with knee dislocation has revealed that the amputation rate increases by 85% every 0.8 h of delay in arterial blood flow reconstruction[ 15 ]. These findings are consistent with the logistic regression analysis performed for each variable (Tables 2 and 3 ). ischemic time( OR = 1.195, P = 0.017,95% CI :1.032–1.383)was an independent risk factor for amputation of popliteal artery injury. A correlation analysis was conducted between the R and S quantitative indicators of injury planes and the ischemic time of the PAI patients, which revealed that lower R and S values were independently correlated with the risk of amputation in PAI patients. In contrast, R (r R =-0.487, P R <0.001) and S (r S =-0.369, P S <0.001) were negatively correlated with ischemic time (Fig. 9 ). The R and S quantitative indicators were negatively correlated with the plane of injury. In PAI patients with a high degree of injury, the distal limb enters an ischemic and hypoxic state earlier, anaerobic metabolism results in the accumulation of many harmful substances, and the blood quickly enters a hypercoagulable state. Early thrombus formation further exacerbates ischaemia in the affected limb, resulting in harmful positive feedback regulation. Patients with such high-plane injuries often experience longer-distance popliteal artery thrombus during surgery, which corresponds to the traditional concept that longer ischemic times result in greater risks of amputation in PAI patients [ 4 – 6 ]. The present study explored the diagnostic efficiency of the injury plane in predicting amputation risk from another perspective using ROC curves for S and R. The area under the curve values for R and S were 0.887 ( P < 0.000, 95% CI : 0.805–0.943) and 0.775 ( P AUC S ( Z = 2.403, P = 0.0162).was identified, indicating that R is superior to S in evaluating amputation risk in PAI patients. Compared with S, R avoids statistical biases caused by differences in popliteal artery length and vascular variability among different patients, indicating that it is a reliable indicator for evaluating the risk of amputation in PAI patients. When the diagnostic thresholds for R and S are set at 0.573 and 11.3 cm, respectively, the diagnostic efficiency is highest, indicating that the plane of blood flow interruption is approximately 57.3% greater than the overall length of the affected popliteal artery. When the distance between the plane of blood flow interruption and the origin of the descending genicular artery in the affected limb is less than 11.3cm, the risk of amputation in patients suddenly increases. This conclusion is related to the anatomical characteristics of the popliteal artery itself [ 21 – 22 ], that is, the location of the origin of the internal and external sural arteries is close to the middle position of the popliteal artery as a whole [ 23 – 24 ], and its blood flow accounts for nearly 19% of the total collateral circulation flow of the popliteal artery [ 25 – 26 ], which is consistent with the statistical conclusions of the present study.When the popliteal artery injury plane of the affected limb is higher than the location of the origin of the internal and external sural arteries (R ≤ 0.573, S ≤ 11.3 cm), it is classified as a high-plane PAI patient. Such patients face an extremely high risk of amputation, with limited collateral circulation, prolonged ischemia time, and severe soft tissue ischemia-reperfusion injury after vascular reconstruction, leading to a high risk of amputation that may even threaten life. Therefore, emergency vascular reconstruction and preventive fasciotomy should be performed, and for fracture reduction, temporary external fixation should be chosen as much as possible to restore alignment without pursuing anatomical reduction excessively internal fixation with steel plates during the emergency period. If the popliteal artery injury plane is lower than the origin of the internal and external sural arteries (R > 0.573, S > 11.3 cm), it is classified as a low-plane PAI patient. These patients have rich collateral circulation, and it is recommended to choose vascular reconstruction followed by internal fixation with steel plates during the phase one to facilitate early functional exercise of the knee joint post-surgery, thereby reducing the patient's hospital stay, number of surgeries, and costs. One of the critical factors in evaluating the risk of amputation and degree of limb ischaemia in PAI patients is the inclusion of the injury plane, which supplements the clinical assessment for the severity of limb injury and ischaemia in PAI patients. Among the many factors that affect the risk of amputation in the present study, the statistical analysis results showed that the injury plane (S, OR S =0.716, P S <0.001, Table 2 ) was a related risk factor for amputation in the affected limb after popliteal artery injury, for every 1 unit (cm) decrease in the injury plane, the risk of amputation decreases to 71.6% of the original plane. Multivariate logistic regression results showed that injury plane (R, OR R =0.876, P R =0.006, Table 3 ) was an independent risk factor for amputation in the affected limb after popliteal artery injury, and for every 1% increase in R, the risk of amputation decreases to 87.6% of the original plane. Notably, the plane of injury also has specific guiding value in the selection of surgical methods. A high plane of injury often means that the adequate collateral circulation of the affected limb is preserved less, the distal limb is severely ischemic, and the risk of amputation is high. Surgeons should strive to establish adequate circulation as soon as possible [ 27 – 30 ] and utilize external fixation brackets to initially fix the fracture and immediately treat the blood vessels [ 3 , 31 – 33 ]. For patients with low injury planes, due to the presence of more collateral circulation to provide blood for the distal ischemic limb, the risk of amputation is relatively low. Therefore, in cases of mild contamination and acceptable soft tissue conditions, surgeons should choose one-stage fracture internal fixation surgery to facilitate early functional exercise of the knee joint after surgery [ 31 – 33 ]. S and R are more objective, accurate, and easy to calculate than the traditional ischemic time and the degree of soft tissue injury to the affected limb. Given these advantages, preoperative S and R can help clinicians better evaluate the risk of amputation in PAI patients. When PAI patients undergoing lower limb arterial CTA examination, further injury classification should be based on whether the vascular injury plane of the affected limb is higher than the location of the origin of the internal and external sural arteries. When the high-plane PAI patients’ischemia time exceeds 6–8 hours, they face an extremely high risk of amputation, defined as a high-risk patient. High-risk patients usually have fewer collateral circulations, prolonged ischemia time, and severe soft tissue ischemia-reperfusion injury after revascularization, resulting in a very high risk of amputation that may even threaten life. Therefore, emergency vascular reconstruction and preventive fasciotomy should be performed, and for fracture reduction, temporary external fixation should be chosen as much as possible to restore alignment without pursuing anatomical reduction excessively internal fixation with steel plates during the emergency period.If the vascular injury plane of the affected limb is lower than the origin of the internal and external sural arteries with ischemia time exceeding 6–8 hours, it is defined as a medium-risk patient. For these patients, when the affected limb has developed tense blisters or the “5p syndrome of bone fascia compartment syndrome”, the Whiteside method should be used for preoperative measurement of the fascial compartment pressure in the affected limb. When patients’fascial compartment pressure exceeding 30 mmHg, we will perform preventive fasciotomy during surgery, instead of performing all medium-risk patients.Because clinical experience indicates that when PAI patients with ischemia time exceeding 6–8 hours undergo preventive fasciotomy, which results open wounds postoperatively on the affected limb, which may increases the risk of infection and undoubtedly complicates and increases the difficulty of secondary plate replacement surgery, prolonging hospital stay and economic burden for the patient.For low-risk patients with an injury plane and ischemia time less than 6–8 hours, it is recommended to choose primary revascularization followed by internal fixation with steel plates to facilitate early functional exercise of the knee joint postoperatively, reducing hospital stay, number of surgeries, and costs for the patient.. The present study had several shortcomings. The present study had a small number of cases and was a single-centre study, resulting in some data bias. In addition to the main confounding factors, such as the Patient Injury Severity Scale (AIS-ISS) score, vascular diameter, degree of variation in both sides of the blood vessels, ischemic time in the affected limb, and degree of injury in the affected limb (MESS), other factors may also interfere, suggesting that further exploration is needed. 5. Conclusion In conclusion, the height of the popliteal artery injury plane is an independent risk factor for amputation in patients with popliteal artery injury, with higher planes of vascular injury resulting in a greater risk of amputation in patients. In terms of evaluating the diagnostic efficiency of the injury plane in predicting amputation risk, R is superior to S. Declarations Funding statement This work was supported by the application of three-dimensional finite element analysis to investigate the relationship between the location of head and face injuries and intervertebral disc–ligament complex injuries in patients with cervical hyperextension injuries and its clinical application (M202145). Author Contribution Jianjie Mao contributed to data acquisition and analysis and drafted the manuscript; Hui Chua and Gengyang Jin contributed to the design and critically revised the manuscript. All the authors provided comments and suggestions, and they approved the publication. References Futchko J, Parsikia A, ,Berezin N et al A propensity-matched analysis of contemporary outcomes of blunt popliteal artery injury[J]. J Vascular Surg 2020, 72(1):1–9 Christina T, Areg G, Jeffry N et al (2019) Racial Disparities in Limb Amputations After Traumatic Vascular Injury[J]. J Clin Orthop Trauma, (10):100–105 Dennis H, Falco et al (2022) Blunt popliteal artery injury following tibiofemoral trauma: vessel-first and bone-first strategy[J]. Eur J Trauma Emerg Surg 48(2):1045–1053 Tan TW, Armstrong FD, Zhang WW (2016) Review of surgical treatment of popliteal artery injury: outcomes of open vs endovascular repair[J]. Vasc Dis Manage 13(8):176–182 Keeley J, Koopmann M, ,Yan H et al (2015) Factors Associated with Amputation Following Popliteal Vascular Injuries[J]. Ann Vasc Surg 29(5):881–882 Lang NW, Joestl JB, Platzer P Characteristics and clinical outcome in patients after popliteal artery injury[J]. J Vasc Surg 2015, 61(6): 1495–1500 Krzysztof A, Tomaszewski,Patrick et al (2016) The evidence-based surgical anatomy of the popliteal artery and the variations in its branching patterns[J]. J Vasc Surg 65(2):521–529 Serkan O, Zulal et al (2020) Popliteal Artery Branching Variations: A Study on Multidetector CT. Angiography[J] Sci Rep 10(1):8147 Hohenberger GM, Konstantiniuk P, Cambiaso-Daniel, Janos et al (2020) The Mangled Extremity Severity Score Fails to be a Good Predictor for Secondary Limb Amputation After Trauma with Vascular Injury in Central Europe[J]. World J Surg 44(3):773–779 Kumar RS, Singhi PK, Chidambaram M (2017) Are We Justified Doing Salvage or Amputation Procedure Based on Mangled Extremity Severity Score in Mangled Upper Extremity Injury[J]. J Orthop Case Rep 7(1):3–8 Paloma A, Marc RN,Sara Q et al (2021) Popliteal artery: Anatomical study and review of the literature[J]. Ann Anat 234:151654 Tomaszewski KA, Popieluszko P, Graves MJ et al The evidence-based surgical anatomy of the popliteal artery and the variations in its branching patterns[J]. J Vasc Surg, 2017,65: 521–529 Cheng QL, Cheng LL, Wang et al (2023) Therapeutic management and amputation options in a long-time delayed blunt popliteal artery injury[J]. Eur J Trauma Emerg Surg 49(undefined):0 Deng QY, Tang BH, Xue C et al (2016) Comparison of the Ability to Predict Mortality between the Injury Severity Score and the New Injury Severity Score: A Meta-Analysis[J]. Int J Environ Res Public Health 13(8):1–12 Talving PKE, Skiada D et al Relationship of creatine kinase elevation and acute kidney injury in pediatric trauma patients[J]. J Trauma Acute Care Surg 2013, 74(3):912–916 Cheng QL, Cheng LL, Wang et al (2023) Therapeutic management and amputation options in a long-time delayed blunt popliteal artery injury[J]. Eur J Trauma Emerg Surg 49(undefined):0 Areg G, Wilson SE, Nii-Kabu K et al Decreased National Rate of Below the Knee Amputation in Patients with Popliteal Artery Injury[J]. Annals of Vascular Surgery,2018. Leigh A, O'Banion R et al (2021) Contemporary outcomes of traumatic popliteal artery injury repair from the popliteal scoring assessment for vascular extremity injury in trauma study[J]. J Vasc Surg 74(5):1573–1580 Ramdass MJ, Muddeen A, Harnarayan P et al Risk factors associated with amputation in civilian popliteal artery trauma[J]. Injury 2018, 49(6): 1188–1192 Maithel S, Fujitani RM, Grigorian A et al (2020) Outcomes and Predictors of Popliteal Artery Injury in Pediatric Trauma[J]. Annals of Vascular Surgery Łukasz O, Piotr et al (2019) Variations in terminal branches of the popliteal artery: cadaveric study[J]. Surg Radiol Anat 41(12):1473–1482 Rogier HJ, Kropman, Geraldine et al (2011) Variations in the anatomy of the popliteal artery and its side branches[J]. Vasc Endovascular Surg 45(6):536–540 Cheng -H, Lin,Yun -H, Hsieh et al (2021) The Medial Sural Artery Perforator Flap in Lower Extremity Reconstruction[J]. Clin Plast Surg 48(2):249–257 Tian XN, Chao G, CongF et al (2019) Clinical significance of injury in different planes of popliteal vessels [J]. Chin J Orthop Surg 27(12):1097–1101 Cheng -H, Lin,Yun -H, Hsieh et al (2021) The Medial Sural Artery Perforator Flap in Lower Extremity Reconstruction[J]. Clin Plast Surg 48(2):249–257 Bahar Y, Erdogan et al (2014) Variations of the popliteal artery branching with multidetector CT angiography[J]. Surg Radiol Anat 37(3):223–230 Barnes CJ, Pietrobon R, Higgins LD (2002) Does the pulse examination in patients with traumatic knee dislocation predict a surgical arterial injury? A meta-analysis[J]. Trauma Inj Infect Crit Care 53(6):1109–1114 Perkins ZB, Yet B, Glasgow S et al (2015) Meta-analysis of prognostic factors for amputation following surgical repair of lower extremity vascular trauma[J]. Br J Surg 102(5):436–450 Fairhurst PG, Wyss TR, Weiss S et al (2018) Popliteal vessel trauma: surgical approaches and the vessel-first strategy[J].Knee. 25(5):849–855 McHenry TP, Holcomb JB, Aoki N (2002) Fractures with major vascular injuries from gunshot wounds: implications of surgical sequence[J].Trauma. 53(4):717–721 Scalea TM, DuBose J, Moore EE et al (2012) Western Trauma Association Critical Decisions in trauma: management of the mangled extremity[J]. Trauma Acute Care Surg 72(1):86–93 Hundersmarck D, Hietbrink F, Leenen LPH et al (2022) Blunt popliteal artery injury following tibiofemoral trauma:vessel-first and bone-first strategy[J]. Eur J Trauma Emerg Surg 48(2):1045–1053 Fox N, Rajani RR, Bokhari F et al Evaluation and management of penetrating lower extremity arterial trauma: An eastern association for the surgery of trauma practice management guideline[J] (2012) Trauma Acute Care Surg 73(5 SUPPL4):315–320 Additional Declarations No competing interests reported. Supplementary Files rawdata.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5925239","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":409576479,"identity":"8d34f570-b062-4074-b5c1-56937318f4b6","order_by":0,"name":"Jianjie Mao","email":"","orcid":"","institution":"The 904th Hospital of Joint Logistic Support Force of PLA","correspondingAuthor":false,"prefix":"","firstName":"Jianjie","middleName":"","lastName":"Mao","suffix":""},{"id":409576480,"identity":"b76b4d73-9335-48ee-97e7-f89213c9a74b","order_by":1,"name":"Hui Chu","email":"","orcid":"","institution":"The 904th Hospital of Joint Logistic Support Force of PLA","correspondingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"Chu","suffix":""},{"id":409576481,"identity":"d5c31ca6-55fa-4224-b3dd-23f7a9733aa9","order_by":2,"name":"GenYang Jin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3ElEQVRIiWNgGAWjYDADNmbGxgcJFTUkaOFjb242eHDmGAla5HiOt0k+bGEmrFLevfeYxM8dtQxsEoltFYkNbAz87d0JeLUYnjmXJtl75jhYy43EHTIMEmfObsCvZUaOmQRv2zGoljNsDAYSuQS0zH9jJvkXqqUgsY2ZsBZ5CR4zad62GgY2noNtDERpMeDJMbaWbTvAw8be2CyRcOYYD0G/yLefMbz5tq1OTr6Z/eHHHxU1cvztvQRsOcDAIsHAcJgHJsCDTzXElgYG5g8MDHUEFY6CUTAKRsEIBgARokbR43j9PgAAAABJRU5ErkJggg==","orcid":"","institution":"The 904th Hospital of Joint Logistic Support Force of PLA","correspondingAuthor":true,"prefix":"","firstName":"GenYang","middleName":"","lastName":"Jin","suffix":""}],"badges":[],"createdAt":"2025-01-29 15:23:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5925239/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5925239/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":75410239,"identity":"0ae13e13-502a-49b1-91cd-1be46a19f9e7","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":65899,"visible":true,"origin":"","legend":"\u003cp\u003eOriginal 3D reconstruction image of lower limb computed tomography angiography in patients with popliteal artery injury. The location of blood flow interruption after popliteal artery injury in the affected limb is shown.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/4e5c72738006d9580623cf05.jpg"},{"id":75410238,"identity":"ebb62278-7334-4665-88f9-00b7a3ff3b75","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":61758,"visible":true,"origin":"","legend":"\u003cp\u003eThree-dimensional reconstruction of lower limb computed tomography angiography in patients with popliteal artery injury. After three-dimensional reconstruction of the lower limb under CTA in patients with popliteal artery injury, the distance from the origin of the descending genicular artery to the origin of the anterior tibial artery in the healthy limb was measured as L (start1-V1, cm), and the distance from the site of interruption of popliteal artery blood flow in the affected limb to the origin of the descending genicular artery was measured as S (start2-V2, cm).\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/7eda2f0b175b43a1cf50ce05.jpg"},{"id":75411781,"identity":"b43f7381-8bdb-4b23-b540-4dad468b2e92","added_by":"auto","created_at":"2025-02-04 09:15:26","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":140540,"visible":true,"origin":"","legend":"\u003cp\u003eThe color difference between the two sides of the vascular injury plane after the interruption of blood supply at the distal end of the limb after the delayed embolization of popliteal artery combined with the fracture around the knee joint. \u003cstrong\u003ea\u003c/strong\u003e After removing the calcaneal traction, the patient underwent external fixation and anterior limb ischemia, showing the color difference on both sides of the vascular injury plane. \u003cstrong\u003eb \u003c/strong\u003eWith the passage of time, after the fracture external fixation of the affected limb, the ischemia of the distal limb was aggravated, and the color difference between the two sides of the injury plane became obvious. The white dashed line represents: the boundary line of the difference in the appearance of limb blood supply caused by the response of the popliteal artery injury plane.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/ec9427085dca533e945e64fa.jpg"},{"id":75410240,"identity":"3a53153d-1927-4028-bf53-c0b7ff85b1d1","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":212590,"visible":true,"origin":"","legend":"\u003cp\u003eDamage to important vessels and nerve was explored, and the type of popliteal artery injury was determined. White indicator arrow: the thromboembolic segment after the embolism of the popliteal artery. Black indicator arrow: the tibial nerve in the popliteal fossa segment.\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/85237fcb57fc9d22f67005c4.jpg"},{"id":75410244,"identity":"f6f2880a-a6ad-4103-a763-5d0a37f8169e","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":194784,"visible":true,"origin":"","legend":"\u003cp\u003eSurgical treatment of embolic segment of popliteal artery. \u003cstrong\u003ea\u003c/strong\u003e Trim the distal end of the embolic segment of the popliteal artery. \u003cstrong\u003eb\u003c/strong\u003e Trim the proximal end of the embolic segment of the popliteal artery. White arrows indicate: contused segment vessels with thrombus.\u003c/p\u003e","description":"","filename":"Figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/0bd211c6de07ae52fedf3bd4.jpg"},{"id":75410246,"identity":"39a9b620-f0a5-421f-8e9e-ad709ccf2923","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":216417,"visible":true,"origin":"","legend":"\u003cp\u003eAnatomy of the popliteal artery of the contused segment with thrombus.\u003cstrong\u003e a \u003c/strong\u003eThe morphology of thrombus located in popliteal artery of contusion segment. \u003cstrong\u003eb\u003c/strong\u003e Embolus removed from the vessel in the contused segment. White arrows indicate: thrombus.\u003c/p\u003e","description":"","filename":"Figure6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/b17189d481503090a5bd4d0d.jpg"},{"id":75411784,"identity":"f28af283-feb2-430f-82c4-144b63ae8f4a","added_by":"auto","created_at":"2025-02-04 09:15:27","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":89149,"visible":true,"origin":"","legend":"\u003cp\u003eIntergroup difference tests for the quantification index S of injury plane height in PAI patients, including injury type, osteofascial compartment syndrome, and fractures. \u003cstrong\u003ea\u003c/strong\u003e Difference in the quantitative index S of the injury plane between patients with a blunt PAI and those with an acute PAI. \u003cstrong\u003eb\u003c/strong\u003e Difference in the quantitative index S test result of the injury plane between patients with combined compartment syndrome and those without combined compartment syndrome. \u003cstrong\u003ec \u003c/strong\u003eDifferential test results of the quantitative index S of the injury plane between patients with combined fracture PAI and those without combined fracture PAI.\u003c/p\u003e","description":"","filename":"Figure7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/32448941852fbd62dee0ab44.jpg"},{"id":75410248,"identity":"e6e18878-8444-4634-a384-99dc9f950823","added_by":"auto","created_at":"2025-02-04 09:07:27","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":88715,"visible":true,"origin":"","legend":"\u003cp\u003eThe R quantitative indicators for injury plane height in PAI patients include injury type, presence or absence of osteofascial compartment syndrome, and presence or absence of bone. Intergroup difference test for folding. \u003cstrong\u003ea\u003c/strong\u003e Difference in the R quantitative index of the injury plane between patients with a blunt PAI and patients with an acute PAI. \u003cstrong\u003eb\u003c/strong\u003e Difference in the R quantitative index of the injury plane between patients with combined compartment syndrome (PAI) and those without combined compartment syndrome (PAI). \u003cstrong\u003ec\u003c/strong\u003e Difference in the R quantitative index of the injury plane between patients with combined fracture PAI and those without combined fracture PAI.\u003c/p\u003e","description":"","filename":"Figure8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/e308b8837793172d54521bcb.jpg"},{"id":75410243,"identity":"3f0abf28-9e29-4d83-99a0-8f6fe6b45eeb","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":107869,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation analysis between the R and S values of the injury plane height and ischemic time in PAI patients. \u003cstrong\u003ea\u003c/strong\u003e The R quantitative indicator of the injury plane in PAI patients is negatively correlated with ischemic time. \u003cstrong\u003eb\u003c/strong\u003e There is a negative correlation between the A quantitative index of the injury plane and ischemic time in PAI patients.\u003c/p\u003e","description":"","filename":"Figure9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/164950719174ee189f11eca4.jpg"},{"id":75411785,"identity":"3d73fe2f-d9f8-4aa1-b39b-0b18339e90c1","added_by":"auto","created_at":"2025-02-04 09:15:27","extension":"jpg","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":118164,"visible":true,"origin":"","legend":"\u003cp\u003eThe R and S quantitative indicators for the height of the injury plane were used to predict the receiver operating characteristic (\u003cem\u003eROC\u003c/em\u003e) curve for amputation risk efficiency, and the area under the curve vales for R and S were compared.\u003c/p\u003e","description":"","filename":"Figure10.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/19d99a8db36a820af04c6bd1.jpg"},{"id":76858547,"identity":"5800c075-b7f4-4160-9465-8711264b75c5","added_by":"auto","created_at":"2025-02-21 13:16:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2229170,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/46a91939-6753-4ea0-ab8b-021c8d837a13.pdf"},{"id":75410237,"identity":"72a23a25-c44f-48ab-bb75-d3a11b712169","added_by":"auto","created_at":"2025-02-04 09:07:26","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":22651,"visible":true,"origin":"","legend":"","description":"","filename":"rawdata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-5925239/v1/dd5a123acad99cc651b3821f.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Exploration of the relationship between the height of the popliteal artery injury plane and the risk of amputation","fulltext":[{"header":"1. Background","content":"\u003cp\u003ePopliteal artery injury (PAI) is a refractory lower limb injury [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] and one of the most threatening peripheral vascular injuries [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. When accompanied by severe soft tissue injury or limb ischaemia, the risk of amputation is usually greater [\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. It is generally believed that 6\u0026ndash;8 h after vascular injury is the golden time to rescue the limbs. However, in some patients whose ischemic time is far longer than 8 h (even up to 48 h), surgery can still successfully save the affected limb. Reviewing the imaging data of these patients after injury, computed tomography angiography (CTA) of the lower limb usually reveals a lower height of the PAI. PAI can be confirmed by physical examination combined with imaging data [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. However, further assessment of the risk of amputation with similar soft tissue injuries and ischemic times is challenging. At present, there are few reports about the risk of amputation on the basis of the height of the PAI. Therefore, the present study aimed to compare and analyse the clinical data of PAI patients and further explore the importance of injury height for amputation risk assessment.\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 General clinical characteristics of patients\u003c/h2\u003e \u003cp\u003eThe general clinical data of 94 patients with popliteal artery injury and knee injury admitted to the 904th Hospital of the PLA Joint Logistics Support Force from January 2019 to December 2024 were retrospectively analysed. The clinical data included age, sex, height, weight, body mass index (BMI), injury site (left and right), injury type, fracture, ligament, vein injury, injury score (ais-iss) [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], limb injury severity score (MESS), and ischemic time of the affected limb. The imaging parameters were defined as follows: \"L\" was defined as the distance from the origin of the descending genicular artery of the contralateral limb to the origin of the anterior tibial artery; \"S\" was defined as the distance from the origin of the descending genicular artery of the affected limb to the blood flow interruption site; and \"R\" was defined as the ratio of S to L (S/L). The inclusion criteria were as follows: 1) patients with a clear history of acute lower limb trauma; 2) patients with unilateral popliteal artery injury and knee joint trauma; 3) patients who were able tolerate surgery. The exclusion criteria were as follows: 1) patients with crush injury, blast injury, firearm injury, or other injuries involving the muscles of the affected limb; 2) patients without the possibility of limb salvage according to the mangled extreme severity score (MESS) [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] were; 3) patients with severe injuries to the head, neck, chest, abdomen, and other parts, as well as patients who received life-threatening rescue and unconditional limb salvage surgery for popliteal artery injury; 4) patients whose CTA imaging data were incomplete; And 5) patients with vasculitis, vascular occlusion ,and other vascular diseases. The study protocol was approved by the Ethical Committee of the 904th Hospital of the Joint Service Support Force of the Chinese People's Liberation Army. Owing to the retrospective nature of the study, the 904th Hospital of the Joint Service Support Force of the Chinese People's Liberation Army waived the need to obtain informed consent.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Imaging diagnosis and grouping\u003c/h2\u003e \u003cp\u003ePatients were divided into an amputation group and a nonamputation group according to whether limb salvage was successful. Preoperative physical examination and CTA of the affected limb were performed to identify the site of vascular injury (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Three-dimensional reconstruction and measurement were performed on the imaging data of the included patients via AW Volume 5 as follows: the distance L from the origin of the descending knee artery to the origin of the anterior tibial artery in the healthy limb and the distance S from the starting site of blood flow interruption in the affected limb to the origin of the descending knee artery (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The length L of the popliteal artery in the affected limb could not be measured due to blood flow interruption caused by injury. In addition, on the basis of the literature, there is no statistically significant difference in the length of the popliteal artery in both lower limbs of the same patient [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]).\u003c/p\u003e\u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Surgical methods and postoperative management\u003c/h2\u003e \u003cp\u003eTraditional surgical treatment was used for 94 patients with popliteal artery injury in the first stage. After initial debridement, external fixation or internal fixation with steel plates and screws were used to correct fractures and dislocations around the knee joint, ensuring that the fractures were aligned and maintained a stable position of the knee joint (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The wound was cut by making an S-shaped incision of approximately 30 cm in the popliteal area, and the skin and subcutaneous tissue were cut layer by layer to create deep fascia after changing the prone position. Damage to the tibial nerve and common peroneal nerve was explored, and the type of popliteal artery injury was determined (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Inactivated soft tissue and blood clots were thoroughly removed, and the damaged blood vessels were trimmed and removed under the microscope to smooth the popliteal artery intima (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). If the length of the injury exceeded 3 cm, the great saphenous vein was taken from the patient's healthy side for vascular transplantation, and a 9\u0026ndash;0 noninvasive suture line was used for two-point bridge anastomosis. After the blood supply was rebuilt, the tourniquet was loosened, and it was determined whether the blood vessels were unobstructed. If there was blood leakage at the anastomotic site, the activity of muscle and soft tissue was visually assessed, and muscle tissue with a pale colour and suspicious necrosis was removed to further repair damaged nerves and tendons. If high calf tension was found, an osteofascial incision was performed for decompression. For PAI patients without combined fractures, uncomplicated popliteal vein embolization, thrombectomy, vascular exploration, vascular repair, and contralateral great saphenous vein transplantation were performed through the posterior popliteal fossa approach. After surgery, the affected limb was maintained in a temperature-appropriate and smoke-free environment, and the knee joint was maintained in a stable position of 20\u0026deg; \u0026minus;\u0026thinsp;30\u0026deg; flexion. Attention was given to the colour, temperature, and vascular pulsation of the affected limb, and various biochemical indicators were detected in a timely manner. Anticoagulation, spasmolysis, anti-infection, and nutritional support were provided on the basis of test indicators to prevent acute renal failure and compartment syndrome [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Statistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analysis was conducted via SPSS 26.0 and MedCalc 19.3 software. The quantitative data are expressed as the means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations, whereas the count data are expressed as percentages. A t test was used to analyse intergroup differences in econometric data that met a normal distribution. A rank sum test was used for econometric data that did not meet a normal distribution. Counting data were subjected to the chi-square test. All variables were analysed by univariate logistic regression analysis. The significant indicators in the univariate logistic regression analysis results were diagnosed as collinear (variance expansion factor\u0026thinsp;\u0026lt;\u0026thinsp;10). After the collinearity indicators were excluded, the significant variables were included in the multivariate logistic regression analysis, and the odds ratios (\u003cem\u003eOR\u003c/em\u003es) and 95% confidence interval (\u003cem\u003eCI\u003c/em\u003e) were further calculated. Receiver characteristic curves for S and R were generated, and the diagnostic value of the injury plane on amputation risk was evaluated. The area under the curve (\u003cem\u003eAUC\u003c/em\u003e) values and 95% CIs were calculated, and the \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e and \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e between the two groups were compared via the DeLong test (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 indicates a statistically significant difference). The distributions of representative values of S and R in the injury plane for injury type, combined fracture, and combined compartment syndrome were compared in PAI patients. Correlation analysis was conducted to investigate the correlation between representative R and S values of the injury plane and the ischemic time in PAI patients. Two-tailed or two-sided tests were used, and statistically significant differences were defined as \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Comparison of baseline data between the two patient groups\u003c/h2\u003e \u003cp\u003eA total of 94 patients were included in this study, including 89 males and 5 females, aged 41 (36,45) years. The causes of injury were as follows: 51 cases of traffic accident injury, 34 cases of high-altitude falling injury, 5 cases of cutting injury, 3 cases of puncture injury, and 1 case of rope strangulation injury. There were 58 cases of closed injury and 36 cases of open injury. There were 47 cases of simple knee dislocation and 61 cases of combined fractures, including 18 cases of simple tibial plateau fractures (11 cases of Schatzker type Ⅰ fractures and 7 cases of Schatzker type Ⅳ fractures) and 7 cases of fractures combined with dislocation. There were 21 cases of simple femoral intercondylar or supracondylar fractures and 15 cases of fractures combined with dislocation (9 cases of Hohl Moore-type fractures and 6 cases of type III fractures). The above patients were divided into an amputation group (n\u0026thinsp;=\u0026thinsp;26) and a nonamputation group (n\u0026thinsp;=\u0026thinsp;68) according to whether limb salvage was successful. There were no deaths, and the amputation rate was 27.7%. Among them, there were 7 cases of delayed amputation due to infection and necrosis of limb wounds after amputation and 4 cases of delayed amputation due to osteomyelitis. Vascular crisis occurred within 1\u0026ndash;3 days after the operation, and 8 cases were amputated after emergency vascular exploration. Two cases involved life-threatening amputation, owing to haemorrhagic shock due to aneurysm rupture, and 5 cases were amputated due to severe renal failure. Among the successful limb salvage patients, 16 experienced foot drop and recovered after secondary Achilles tendon lengthening surgery. Among the 61 patients with concurrent fractures of different parts, two patients experienced delayed fracture healing 8 months after surgery and underwent secondary bone grafting and plate internal fixation before healing. The remaining patients all experienced primary healing. The present study compared the severity of limb injuries (MESS score), ischemic time, age, sex, body mass index, injury type, systemic injury score (AIS-ISS score), inner diameter D (mm) of the affected limb blood flow interruption site, combined fractures, and combined fascial compartment syndrome in the two groups of patients. Baseline data, such as combined ligament injuries, were subjected to intergroup difference tests (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). There were no significant differences in the baseline data, such as ischaemia time and severity of limb injury (MESS score), between the two groups of patients (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). After removing the aforementioned confounding factors as much as possible, the impact of the injury plan on the risk of amputation in PAI patients was explored, which revealed a significant difference in the injury plane (S, R) between the two groups (\u003cem\u003et\u003c/em\u003e\u003csub\u003es\u003c/sub\u003e=4.500, \u003cem\u003eP\u003c/em\u003e\u003csub\u003es\u003c/sub\u003e\u0026lt;0.00; \u003cem\u003et\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e=6.974, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e\u0026lt;0.00).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of baseline data and main observation indicators between the two groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003egroup\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAmputation group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-Amputation group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTest value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge( year)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41.46\u0026thinsp;\u0026plusmn;\u0026thinsp;7.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.75\u0026thinsp;\u0026plusmn;\u0026thinsp;6.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e=-1.069\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.288\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI(kg∙m-2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.64\u0026thinsp;\u0026plusmn;\u0026thinsp;2.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.90\u0026thinsp;\u0026plusmn;\u0026thinsp;3.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.343\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.305\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIschemic time(h)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15.46\u0026thinsp;\u0026plusmn;\u0026thinsp;6.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.50\u0026thinsp;\u0026plusmn;\u0026thinsp;3.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e=-8.177\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAIS-ISSscore\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.24\u0026thinsp;\u0026plusmn;\u0026thinsp;3.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.74\u0026thinsp;\u0026plusmn;\u0026thinsp;3.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.581\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.563\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMESS-score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.23\u0026thinsp;\u0026plusmn;\u0026thinsp;1.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.75\u0026thinsp;\u0026plusmn;\u0026thinsp;1.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e=-1.144\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.255\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.402\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.614\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24(92.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65(95.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003efemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(7.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(4.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePart[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.462\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.164\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eleft\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15(57.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27(39.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eright\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(42.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41(60.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of injury[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5.723\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.022\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eblunt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23(88.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43(63.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003esharp\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(11.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25(36.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOpen wound[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.984\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eopen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(38.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26(38.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eclosed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16(61.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42(61.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined fracture[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.976\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.055\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewith\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(80.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40(58.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewithout\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5(19.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28(41.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTypes of vascular injury[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.322\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.643\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003erupture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12(46.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27(39.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eno rupture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14(53.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41(60.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined compartment syndrome[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;19.552\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewith\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15(57.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9(13.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewithout\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(42.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e59(86.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined ligament injury[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.862\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.478\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewith\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8(30.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28(41.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewithout\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18(69.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40(58.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined vein injury[number(%)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eχ2\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.632\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.493\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewith\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15(57.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33(48.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewithout\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(42.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35(51.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eD(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.76\u0026thinsp;\u0026plusmn;\u0026thinsp;2.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.621\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.536\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS(cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.77\u0026thinsp;\u0026plusmn;\u0026thinsp;2.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.02\u0026thinsp;\u0026plusmn;\u0026thinsp;3.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eL(cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.77\u0026thinsp;\u0026plusmn;\u0026thinsp;4.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.51\u0026thinsp;\u0026plusmn;\u0026thinsp;4.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e=-0.237\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.813\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR\u0026thinsp;=\u0026thinsp;S/L(%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e47.51\u0026thinsp;\u0026plusmn;\u0026thinsp;8.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65.49\u0026thinsp;\u0026plusmn;\u0026thinsp;11.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.974\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: D represents the inner diameter of the affected limb popliteal artery blood flow interruption point (mm); S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; L represents the distance from the opening of the descending genicular artery on the healthy limb to the origin of the anterior tibial artery (cm); R is the ratio of S to L (%).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Analysis of amputation risk factors\u003c/h2\u003e \u003cp\u003eUnivariate logistic regression analysis was performed for each variable (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), which revealed significant differences (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in injury type, ischemic time, combined fractures, combined fascial compartment syndrome, S, and R. Collinearity diagnostic analysis of the above indicators revealed that there was no collinearity among the indicators (variance inflation factor\u0026thinsp;\u0026lt;\u0026thinsp;10). After these six variables were incorporated, further multivariate logistic regression analysis was performed (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). ischemic time (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.195, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.017,95% \u003cem\u003eCI\u003c/em\u003e:1.032\u0026ndash;1.383),concomitant fascial compartment syndrome (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5.509, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.055,95% \u003cem\u003eCI\u003c/em\u003e:0.967\u0026ndash;31.376), distance S from the site of blood flow interruption in the affected limb to the opening of the descending knee artery (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.792, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.166,95% \u003cem\u003eCI\u003c/em\u003e:0.570\u0026ndash;1.102),, and the ratio of injury distance S to the distance L from the opening of the anterior tibial artery in the healthy limb (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.876, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006,95% \u003cem\u003eCI\u003c/em\u003e:0.797\u0026ndash;0.963)were independent risk factors for amputation in patients with PAI.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eUnivariate logistic regression results\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003evariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eOR\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003e95%CI\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.495\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.457\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.215\u0026ndash;16.359\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIschemic time\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.312\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.367\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.211\u0026ndash;1.543\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined compartment syndrome\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.190\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8.939\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3.136\u0026ndash;25.482\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined fracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.078\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.052\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.940\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.990\u0026ndash;8.730\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.334\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.716\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.602\u0026ndash;0.852\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.170\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.844\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.784\u0026ndash;0.909\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; R is the ratio of S to L (%).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultivariate logistic regression results\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003evariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eOR\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003e95%CI\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.727\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.622\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.822\u0026ndash;38.438\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIschemic time\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.178\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.017\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.195\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.032\u0026ndash;1.383\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined compartment syndrome\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.706\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.055\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.509\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.967\u0026ndash;31.376\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined fracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.613\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.709\u0026ndash;35.530\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.233\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.166\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.792\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.570\u0026ndash;1.102\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e-0.132\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.876\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.797\u0026ndash;0.963\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; R is the ratio of S to L (%).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e3.3 Correlation analysis between injury plane and ischemic time, injury type, combined fractures, and combined compartment syndrome of bone and fascia\u003c/p\u003e \u003cp\u003eThe correlations between a series of clinical features, such as ischaemia time, injury type, combined fractures, and combined fascial compartment syndrome, in PAI patients and the S and R preoperative injury planes were evaluated (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, Figs.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e). A t test was performed between groups before the correlation analysis was conducted, which revealed the following results: S (\u003cem\u003et\u003c/em\u003e\u003csub\u003et\u003c/sub\u003e=0.328, \u003cem\u003eP\u003c/em\u003e\u003csub\u003et\u003c/sub\u003e=0.744; \u003cem\u003et\u003c/em\u003e\u003csub\u003eF\u003c/sub\u003e=0.753, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eF\u003c/sub\u003e=0.453; \u003cem\u003et\u003c/em\u003e\u003csub\u003eO\u003c/sub\u003e=1.874, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eO\u003c/sub\u003e=0.064) and R (\u003cem\u003et\u003c/em\u003e\u003csub\u003et\u003c/sub\u003e=0.508, \u003cem\u003eP\u003c/em\u003e\u003csub\u003et\u003c/sub\u003e=0.613; \u003cem\u003et\u003c/em\u003e\u003csub\u003eF\u003c/sub\u003e=1.480, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eF\u003c/sub\u003e=0.142; t\u003csub\u003eO\u003c/sub\u003e=3.148, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eO\u003c/sub\u003e=0.002). Pearson correlation analysis was performed on the S and R injury planes and the ischemic time, which revealed that \u003cem\u003er\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e=-0.487, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e\u0026lt;0.001, \u003cem\u003er\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e=-0.369, and \u003cem\u003eP\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e\u0026lt;0.001.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of the distributions of injury planes S and R according to injury type, combined fracture, and combined bone compartment syndrome\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"10\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eN\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eS(cm)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eTest value\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003eN\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eR\u0026thinsp;=\u0026thinsp;S/L(%)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003eTest value\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDamage type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBlunt injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e11.05\u0026thinsp;\u0026plusmn;\u0026thinsp;3.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u0026thinsp;=\u0026thinsp;0.328\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.744\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e60.05\u0026thinsp;\u0026plusmn;\u0026thinsp;14.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.508\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0.613\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSharp injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e11.30\u0026thinsp;\u0026plusmn;\u0026thinsp;3.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e61.63\u0026thinsp;\u0026plusmn;\u0026thinsp;12.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCombined fracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e10.93\u0026thinsp;\u0026plusmn;\u0026thinsp;3.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u0026thinsp;=\u0026thinsp;0.753\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.453\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e58.98\u0026thinsp;\u0026plusmn;\u0026thinsp;14.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.480\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0.142\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-fracture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e11.49\u0026thinsp;\u0026plusmn;\u0026thinsp;3.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e63.35\u0026thinsp;\u0026plusmn;\u0026thinsp;12.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOFS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCombined-OFS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e10.00\u0026thinsp;\u0026plusmn;\u0026thinsp;3.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003et\u0026thinsp;=\u0026thinsp;1.874\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.064\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e53.23\u0026thinsp;\u0026plusmn;\u0026thinsp;11.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.148\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-OFS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e11.51\u0026thinsp;\u0026plusmn;\u0026thinsp;3.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e63.01\u0026thinsp;\u0026plusmn;\u0026thinsp;13.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote: S represents the distance (cm) from the origin of the descending genicular artery caused by the location of blood flow interruption in the affected limb; L represents the distance from the opening of the descending genicular artery on the healthy limb to the origin of the anterior tibial artery (cm); R is the ratio of S to L (%), and OFS represents compartment syndrome of the bone fascia.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Predictive efficacy of different injury planes on amputation risk in PAI patients\u003c/h2\u003e \u003cp\u003eEvaluation of the diagnostic efficiency of the injury plane in predicting amputation risk through area under the curve (\u003cem\u003eAUC\u003c/em\u003e) values of S and R (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e) demonstrated that the area under the curve values of R and S were 0.887 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.805\u0026ndash;0.943) and 0.775 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.677\u0026ndash;0.854), respectively. The DeLong test was used for comparison as follows: \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e \u0026gt;\u003cem\u003eAUC\u003c/em\u003e\u003csub\u003e\u003cem\u003eS\u003c/em\u003e\u003c/sub\u003e (\u003cem\u003eZ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.403, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0162). The diagnostic efficiency was highest when the R and S diagnostic thresholds were 0.573 and 11.3 cm, respectively.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eSome scholars believe that the amputation rate of PAI patients is related to their preserved collateral circulation supply [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. When a patient experiences popliteal artery injury, the amount of adequate collateral circulation generated is determined by the blood flow interruption plane at the time of injury. When the plane of vascular injury in the affected limb is low, the central collateral circulation is not disrupted or blocked, and blood flow can bypass the interruption site of the main popliteal artery, providing compensatory blood for the distal ischemic and hypoxic limbs. To a certain extent, this can reduce the pathological substances produced by anaerobic metabolism after ischaemia, delay ischemic soft tissue necrosis, and minimize the degree of limb injury, thereby reducing the risk of amputation for patients. In the present study, univariate logistic regression analysis was performed on each variable, and the distance S from the site of blood flow interruption in the affected limb to the origin of the descending genicular artery (OR\u0026thinsp;=\u0026thinsp;0.716, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001,95% CI:0.602\u0026ndash;0.852,Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), was determined. Multivariate logistic regression results showed that the ratio R(OR\u0026thinsp;=\u0026thinsp;0.876, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006,95% CI:0.797\u0026ndash;0.963,Tables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) between the injury distance S and the distance L from the origin of the descending genicular artery to the origin of the anterior tibial artery in the healthy limb suggested that the height of the injury plane further affects or represents the number of collateral branches retained after injury, which in turn affects the amputation rate. In addition, the receiver operating characteristic (\u003cem\u003eROC\u003c/em\u003e) curves of S and R were used to evaluate the diagnostic efficiency of the injury plane in predicting amputation risk (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e), which indicated that the \u003cem\u003eAUC\u003c/em\u003e values of R and S were 0.887 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.805\u0026ndash;0.943) and 0.775 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e:0.677\u0026ndash;0.854),respectively, representing statistically significant differences. Therefore, in cases of similar injuries and ischemic times, the plane of injury may be another critical factor in assessing the risk of amputation in affected limbs. Currently, few studies support the view that the plane of injury can affect the risk of amputation in PAI patients.\u003c/p\u003e \u003cp\u003eWhen the height of the popliteal artery injury plane is quantified, the essence of S and R represents the location of blood flow interruption. The amount of sufficient collateral circulation retained in PAI patients after injury depends on the location of blood flow interruption. Greater S and R values result in lower planes of injury, ultimately preserving more collateral circulation in the affected limb. Greater abundance of collateral compensatory blood supply in the distal ischemic limb results in fewer pathological substances produced by anaerobic metabolism per unit time and milder degree of soft tissue ischaemia and hypoxia. Thus, PAI patients with a low degree of injury face a lower risk of amputation under the premise of a similar degree of limb soft tissue injury and similar ischemic times. This conclusion is consistent with some statistical analysis results in the present study. A t test comparison between the S and R scores of amputated and nonamputated patients revealed significant differences in S and R between the two groups(\u003cem\u003et\u003c/em\u003e\u003csub\u003es\u003c/sub\u003e=4.500, \u003cem\u003eP\u003c/em\u003e\u003csub\u003es\u003c/sub\u003e\u0026lt;0.00; t\u003csub\u003eR\u003c/sub\u003e=6.974, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e\u0026lt;0.00). The postoperative amputation rate of patients with high injury planes was much greater than that of patients with low injury planes.\u003c/p\u003e \u003cp\u003eThe ischemic time of the affected limb after popliteal artery injury is usually considered the main traditional factor affecting the risk of amputation. Longer ischemic times result in greater amounts of waste accumulated after anaerobic metabolism of the tissue, more severe degrees of muscle injury, and greater risk of amputation. A previous study on popliteal artery injury combined with knee dislocation has revealed that the amputation rate increases by 85% every 0.8 h of delay in arterial blood flow reconstruction[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. These findings are consistent with the logistic regression analysis performed for each variable (Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). ischemic time(\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.195, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.017,95% \u003cem\u003eCI\u003c/em\u003e:1.032\u0026ndash;1.383)was an independent risk factor for amputation of popliteal artery injury. A correlation analysis was conducted between the R and S quantitative indicators of injury planes and the ischemic time of the PAI patients, which revealed that lower R and S values were independently correlated with the risk of amputation in PAI patients. In contrast, R (r\u003csub\u003eR\u003c/sub\u003e=-0.487, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e\u0026lt;0.001) and S (r\u003csub\u003eS\u003c/sub\u003e=-0.369, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e\u0026lt;0.001) were negatively correlated with ischemic time (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e). The R and S quantitative indicators were negatively correlated with the plane of injury. In PAI patients with a high degree of injury, the distal limb enters an ischemic and hypoxic state earlier, anaerobic metabolism results in the accumulation of many harmful substances, and the blood quickly enters a hypercoagulable state. Early thrombus formation further exacerbates ischaemia in the affected limb, resulting in harmful positive feedback regulation. Patients with such high-plane injuries often experience longer-distance popliteal artery thrombus during surgery, which corresponds to the traditional concept that longer ischemic times result in greater risks of amputation in PAI patients [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe present study explored the diagnostic efficiency of the injury plane in predicting amputation risk from another perspective using \u003cem\u003eROC\u003c/em\u003e curves for S and R. The area under the curve values for R and S were 0.887 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.805\u0026ndash;0.943) and 0.775 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.677\u0026ndash;0.854), respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e), and a comparison of \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003e\u003cem\u003eR\u003c/em\u003e\u003c/sub\u003e \u0026gt;\u003cem\u003eAUC\u003c/em\u003e\u003csub\u003e\u003cem\u003eS\u003c/em\u003e\u003c/sub\u003e (\u003cem\u003eZ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.403, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0162).was identified, indicating that R is superior to S in evaluating amputation risk in PAI patients. Compared with S, R avoids statistical biases caused by differences in popliteal artery length and vascular variability among different patients, indicating that it is a reliable indicator for evaluating the risk of amputation in PAI patients. When the diagnostic thresholds for R and S are set at 0.573 and 11.3 cm, respectively, the diagnostic efficiency is highest, indicating that the plane of blood flow interruption is approximately 57.3% greater than the overall length of the affected popliteal artery. When the distance between the plane of blood flow interruption and the origin of the descending genicular artery in the affected limb is less than 11.3cm, the risk of amputation in patients suddenly increases. This conclusion is related to the anatomical characteristics of the popliteal artery itself [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], that is, the location of the origin of the internal and external sural arteries is close to the middle position of the popliteal artery as a whole [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], and its blood flow accounts for nearly 19% of the total collateral circulation flow of the popliteal artery [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], which is consistent with the statistical conclusions of the present study.When the popliteal artery injury plane of the affected limb is higher than the location of the origin of the internal and external sural arteries (R\u0026thinsp;\u0026le;\u0026thinsp;0.573, S\u0026thinsp;\u0026le;\u0026thinsp;11.3 cm), it is classified as a high-plane PAI patient. Such patients face an extremely high risk of amputation, with limited collateral circulation, prolonged ischemia time, and severe soft tissue ischemia-reperfusion injury after vascular reconstruction, leading to a high risk of amputation that may even threaten life. Therefore, emergency vascular reconstruction and preventive fasciotomy should be performed, and for fracture reduction, temporary external fixation should be chosen as much as possible to restore alignment without pursuing anatomical reduction excessively internal fixation with steel plates during the emergency period. If the popliteal artery injury plane is lower than the origin of the internal and external sural arteries (R\u0026thinsp;\u0026gt;\u0026thinsp;0.573, S\u0026thinsp;\u0026gt;\u0026thinsp;11.3 cm), it is classified as a low-plane PAI patient. These patients have rich collateral circulation, and it is recommended to choose vascular reconstruction followed by internal fixation with steel plates during the phase one to facilitate early functional exercise of the knee joint post-surgery, thereby reducing the patient's hospital stay, number of surgeries, and costs.\u003c/p\u003e \u003cp\u003eOne of the critical factors in evaluating the risk of amputation and degree of limb ischaemia in PAI patients is the inclusion of the injury plane, which supplements the clinical assessment for the severity of limb injury and ischaemia in PAI patients. Among the many factors that affect the risk of amputation in the present study, the statistical analysis results showed that the injury plane (S, \u003cem\u003eOR\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e=0.716, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e\u003cem\u003eS\u003c/em\u003e\u003c/sub\u003e\u0026lt;0.001, Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) was a related risk factor for amputation in the affected limb after popliteal artery injury, for every 1 unit (cm) decrease in the injury plane, the risk of amputation decreases to 71.6% of the original plane. Multivariate logistic regression results showed that injury plane (R, OR\u003csub\u003eR\u003c/sub\u003e=0.876, \u003cem\u003eP\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e=0.006, Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) was an independent risk factor for amputation in the affected limb after popliteal artery injury, and for every 1% increase in R, the risk of amputation decreases to 87.6% of the original plane. Notably, the plane of injury also has specific guiding value in the selection of surgical methods. A high plane of injury often means that the adequate collateral circulation of the affected limb is preserved less, the distal limb is severely ischemic, and the risk of amputation is high. Surgeons should strive to establish adequate circulation as soon as possible [\u003cspan additionalcitationids=\"CR28 CR29\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] and utilize external fixation brackets to initially fix the fracture and immediately treat the blood vessels [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan additionalcitationids=\"CR32\" citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. For patients with low injury planes, due to the presence of more collateral circulation to provide blood for the distal ischemic limb, the risk of amputation is relatively low. Therefore, in cases of mild contamination and acceptable soft tissue conditions, surgeons should choose one-stage fracture internal fixation surgery to facilitate early functional exercise of the knee joint after surgery [\u003cspan additionalcitationids=\"CR32\" citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eS and R are more objective, accurate, and easy to calculate than the traditional ischemic time and the degree of soft tissue injury to the affected limb. Given these advantages, preoperative S and R can help clinicians better evaluate the risk of amputation in PAI patients. When PAI patients undergoing lower limb arterial CTA examination, further injury classification should be based on whether the vascular injury plane of the affected limb is higher than the location of the origin of the internal and external sural arteries. When the high-plane PAI patients\u0026rsquo;ischemia time exceeds 6\u0026ndash;8 hours, they face an extremely high risk of amputation, defined as a high-risk patient. High-risk patients usually have fewer collateral circulations, prolonged ischemia time, and severe soft tissue ischemia-reperfusion injury after revascularization, resulting in a very high risk of amputation that may even threaten life. Therefore, emergency vascular reconstruction and preventive fasciotomy should be performed, and for fracture reduction, temporary external fixation should be chosen as much as possible to restore alignment without pursuing anatomical reduction excessively internal fixation with steel plates during the emergency period.If the vascular injury plane of the affected limb is lower than the origin of the internal and external sural arteries with ischemia time exceeding 6\u0026ndash;8 hours, it is defined as a medium-risk patient. For these patients, when the affected limb has developed tense blisters or the \u0026ldquo;5p syndrome of bone fascia compartment syndrome\u0026rdquo;, the Whiteside method should be used for preoperative measurement of the fascial compartment pressure in the affected limb. When patients\u0026rsquo;fascial compartment pressure exceeding 30 mmHg, we will perform preventive fasciotomy during surgery, instead of performing all medium-risk patients.Because clinical experience indicates that when PAI patients with ischemia time exceeding 6\u0026ndash;8 hours undergo preventive fasciotomy, which results open wounds postoperatively on the affected limb, which may increases the risk of infection and undoubtedly complicates and increases the difficulty of secondary plate replacement surgery, prolonging hospital stay and economic burden for the patient.For low-risk patients with an injury plane and ischemia time less than 6\u0026ndash;8 hours, it is recommended to choose primary revascularization followed by internal fixation with steel plates to facilitate early functional exercise of the knee joint postoperatively, reducing hospital stay, number of surgeries, and costs for the patient.. The present study had several shortcomings. The present study had a small number of cases and was a single-centre study, resulting in some data bias. In addition to the main confounding factors, such as the Patient Injury Severity Scale (AIS-ISS) score, vascular diameter, degree of variation in both sides of the blood vessels, ischemic time in the affected limb, and degree of injury in the affected limb (MESS), other factors may also interfere, suggesting that further exploration is needed.\u003c/p\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eIn conclusion, the height of the popliteal artery injury plane is an independent risk factor for amputation in patients with popliteal artery injury, with higher planes of vascular injury resulting in a greater risk of amputation in patients. In terms of evaluating the diagnostic efficiency of the injury plane in predicting amputation risk, R is superior to S.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding statement\u003c/h2\u003e \u003cp\u003eThis work was supported by the application of three-dimensional finite element analysis to investigate the relationship between the location of head and face injuries and intervertebral disc\u0026ndash;ligament complex injuries in patients with cervical hyperextension injuries and its clinical application (M202145).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJianjie Mao contributed to data acquisition and analysis and drafted the manuscript; Hui Chua and Gengyang Jin contributed to the design and critically revised the manuscript. All the authors provided comments and suggestions, and they approved the publication.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eFutchko J, Parsikia A, ,Berezin N et al A propensity-matched analysis of contemporary outcomes of blunt popliteal artery injury[J]. J Vascular Surg 2020, 72(1):1\u0026ndash;9\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChristina T, Areg G, Jeffry N et al (2019) Racial Disparities in Limb Amputations After Traumatic Vascular Injury[J]. J Clin Orthop Trauma, (10):100\u0026ndash;105\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDennis H, Falco et al (2022) Blunt popliteal artery injury following tibiofemoral trauma: vessel-first and bone-first strategy[J]. Eur J Trauma Emerg Surg 48(2):1045\u0026ndash;1053\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTan TW, Armstrong FD, Zhang WW (2016) Review of surgical treatment of popliteal artery injury: outcomes of open vs endovascular repair[J]. Vasc Dis Manage 13(8):176\u0026ndash;182\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKeeley J, Koopmann M, ,Yan H et al (2015) Factors Associated with Amputation Following Popliteal Vascular Injuries[J]. Ann Vasc Surg 29(5):881\u0026ndash;882\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLang NW, Joestl JB, Platzer P Characteristics and clinical outcome in patients after popliteal artery injury[J]. J Vasc Surg 2015, 61(6): 1495\u0026ndash;1500\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKrzysztof A, Tomaszewski,Patrick et al (2016) The evidence-based surgical anatomy of the popliteal artery and the variations in its branching patterns[J]. J Vasc Surg 65(2):521\u0026ndash;529\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSerkan O, Zulal et al (2020) Popliteal Artery Branching Variations: A Study on Multidetector CT. Angiography[J] Sci Rep 10(1):8147\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHohenberger GM, Konstantiniuk P, Cambiaso-Daniel, Janos et al (2020) The Mangled Extremity Severity Score Fails to be a Good Predictor for Secondary Limb Amputation After Trauma with Vascular Injury in Central Europe[J]. World J Surg 44(3):773\u0026ndash;779\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKumar RS, Singhi PK, Chidambaram M (2017) Are We Justified Doing Salvage or Amputation Procedure Based on Mangled Extremity Severity Score in Mangled Upper Extremity Injury[J]. J Orthop Case Rep 7(1):3\u0026ndash;8\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePaloma A, Marc RN,Sara Q et al (2021) Popliteal artery: Anatomical study and review of the literature[J]. Ann Anat 234:151654\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTomaszewski KA, Popieluszko P, Graves MJ et al The evidence-based surgical anatomy of the popliteal artery and the variations in its branching patterns[J]. J Vasc Surg, 2017,65: 521\u0026ndash;529\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCheng QL, Cheng LL, Wang et al (2023) Therapeutic management and amputation options in a long-time delayed blunt popliteal artery injury[J]. Eur J Trauma Emerg Surg 49(undefined):0\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDeng QY, Tang BH, Xue C et al (2016) Comparison of the Ability to Predict Mortality between the Injury Severity Score and the New Injury Severity Score: A Meta-Analysis[J]. Int J Environ Res Public Health 13(8):1\u0026ndash;12\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTalving PKE, Skiada D et al Relationship of creatine kinase elevation and acute kidney injury in pediatric trauma patients[J]. J Trauma Acute Care Surg 2013, 74(3):912\u0026ndash;916\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCheng QL, Cheng LL, Wang et al (2023) Therapeutic management and amputation options in a long-time delayed blunt popliteal artery injury[J]. Eur J Trauma Emerg Surg 49(undefined):0\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAreg G, Wilson SE, Nii-Kabu K et al Decreased National Rate of Below the Knee Amputation in Patients with Popliteal Artery Injury[J]. Annals of Vascular Surgery,2018.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeigh A, O'Banion R et al (2021) Contemporary outcomes of traumatic popliteal artery injury repair from the popliteal scoring assessment for vascular extremity injury in trauma study[J]. J Vasc Surg 74(5):1573\u0026ndash;1580\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRamdass MJ, Muddeen A, Harnarayan P et al Risk factors associated with amputation in civilian popliteal artery trauma[J]. Injury 2018, 49(6): 1188\u0026ndash;1192\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaithel S, Fujitani RM, Grigorian A et al (2020) Outcomes and Predictors of Popliteal Artery Injury in Pediatric Trauma[J]. Annals of Vascular Surgery\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eŁukasz O, Piotr et al (2019) Variations in terminal branches of the popliteal artery: cadaveric study[J]. Surg Radiol Anat 41(12):1473\u0026ndash;1482\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRogier HJ, Kropman, Geraldine et al (2011) Variations in the anatomy of the popliteal artery and its side branches[J]. Vasc Endovascular Surg 45(6):536\u0026ndash;540\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCheng -H, Lin,Yun -H, Hsieh et al (2021) The Medial Sural Artery Perforator Flap in Lower Extremity Reconstruction[J]. Clin Plast Surg 48(2):249\u0026ndash;257\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTian XN, Chao G, CongF et al (2019) Clinical significance of injury in different planes of popliteal vessels [J]. Chin J Orthop Surg 27(12):1097\u0026ndash;1101\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCheng -H, Lin,Yun -H, Hsieh et al (2021) The Medial Sural Artery Perforator Flap in Lower Extremity Reconstruction[J]. Clin Plast Surg 48(2):249\u0026ndash;257\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBahar Y, Erdogan et al (2014) Variations of the popliteal artery branching with multidetector CT angiography[J]. Surg Radiol Anat 37(3):223\u0026ndash;230\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarnes CJ, Pietrobon R, Higgins LD (2002) Does the pulse examination in patients with traumatic knee dislocation predict a surgical arterial injury? A meta-analysis[J]. Trauma Inj Infect Crit Care 53(6):1109\u0026ndash;1114\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePerkins ZB, Yet B, Glasgow S et al (2015) Meta-analysis of prognostic factors for amputation following surgical repair of lower extremity vascular trauma[J]. Br J Surg 102(5):436\u0026ndash;450\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFairhurst PG, Wyss TR, Weiss S et al (2018) Popliteal vessel trauma: surgical approaches and the vessel-first strategy[J].Knee. 25(5):849\u0026ndash;855\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMcHenry TP, Holcomb JB, Aoki N (2002) Fractures with major vascular injuries from gunshot wounds: implications of surgical sequence[J].Trauma. 53(4):717\u0026ndash;721\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eScalea TM, DuBose J, Moore EE et al (2012) Western Trauma Association Critical Decisions in trauma: management of the mangled extremity[J]. Trauma Acute Care Surg 72(1):86\u0026ndash;93\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHundersmarck D, Hietbrink F, Leenen LPH et al (2022) Blunt popliteal artery injury following tibiofemoral trauma:vessel-first and bone-first strategy[J]. Eur J Trauma Emerg Surg 48(2):1045\u0026ndash;1053\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFox N, Rajani RR, Bokhari F et al Evaluation and management of penetrating lower extremity arterial trauma: An eastern association for the surgery of trauma practice management\u003c/span\u003e \u003cspan\u003eguideline[J] (2012) Trauma Acute Care Surg 73(5 SUPPL4):315\u0026ndash;320\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Popliteal artery, Damage plane, Risk of amputation, Trauma","lastPublishedDoi":"10.21203/rs.3.rs-5925239/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5925239/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eThe aim of the present study was to explore the impact of different planes of popliteal artery injury (PAI) on the risk of amputation in affected limbs.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective analysis was conducted on ninety-four patients who underwent PAI; these patients were divided into an amputation group (n\u0026thinsp;=\u0026thinsp;26) and a nonamputation group (n\u0026thinsp;=\u0026thinsp;68) on the basis of whether limb preservation was successful. The data were reconstructed from computed tomography angiography (CTA) of the patients\u0026rsquo; lower limbs and measured via AW Volume Share 5 software. The height of the popliteal artery injury surface was quantified as follows: \"L\" was defined as the distance from the origin of the descending genicular artery of the contralateral limb to the origin of the anterior tibial artery; \"S\" was defined as the distance from the origin of the descending genicular artery of the affected limb to the blood flow interruption site; and \"R\" was defined as the ratio of S to L (S/L). The risk factors for amputation in patients with PAI were also analysed.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eUnivariate and multivariate logistic regression analyses revealed that R (odds ratio [\u003cem\u003eOR\u003c/em\u003e]\u0026thinsp;=\u0026thinsp;0.876, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006,95% \u003cem\u003eCI\u003c/em\u003e:0.797\u0026ndash;0.963), S (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.792, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.166,95% \u003cem\u003eCI\u003c/em\u003e:0.570\u0026ndash;1.102), ischemic time (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.195, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.017,95% \u003cem\u003eCI\u003c/em\u003e:1.032\u0026ndash;1.383), and compartment syndrome (\u003cem\u003eOR\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5.509, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.055,95% \u003cem\u003eCI\u003c/em\u003e:0.967\u0026ndash;31.376) were independent risk factors for amputation in patients with PAI. The receiver operating characteristic (ROC) curve revealed that the \u003cem\u003eAUC\u003c/em\u003e values were 0.887 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.805\u0026ndash;0.943) and 0.775 (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000, 95% \u003cem\u003eCI\u003c/em\u003e: 0.677\u0026ndash;0.854) for R and S, respectively. The diagnostic efficiency was highest when the diagnostic threshold values were 0.573 and 11.3 cm, for R and S, respectively. Moreover, the \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003eR\u003c/sub\u003e was greater than the \u003cem\u003eAUC\u003c/em\u003e\u003csub\u003eS\u003c/sub\u003e (\u003cem\u003eZ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.403, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0162).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThe height of the PAI plane is an independent risk factor for amputation in patients with PAI. Greater planes of vascular injury result in greater risk of amputation. R is better than S in the diagnosis of amputation risk in patients with PAI.\u003c/p\u003e","manuscriptTitle":"Exploration of the relationship between the height of the popliteal artery injury plane and the risk of amputation","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-02-04 09:07:21","doi":"10.21203/rs.3.rs-5925239/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"def8e393-1930-48b7-9f6f-df4c5344a94e","owner":[],"postedDate":"February 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-02-21T13:08:42+00:00","versionOfRecord":[],"versionCreatedAt":"2025-02-04 09:07:21","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5925239","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5925239","identity":"rs-5925239","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}