Comparison of early periprosthetic femoral complications following cementless total hip arthroplasty between fit-and-fill stems and tapered-wedge stems: a propensity score matching study from a single center

Comparison of early periprosthetic femoral complications following cementless total hip arthroplasty between fit-and-fill stems and tapered-wedge stems: a propensity score matching study from a single center | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Comparison of early periprosthetic femoral complications following cementless total hip arthroplasty between fit-and-fill stems and tapered-wedge stems: a propensity score matching study from a single center Satoshi Ikemura, Kyohei Shiomoto, Goro Motomura, Satoshi Hamai, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5822802/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Background: Few reports have focused on major perioperative complications, including periprosthetic femoral fracture (PFF) and stem subsidence in cementless total hip arthroplasty (THA), after standardizing the patient’s background and comparing different femoral component design at a single center. Therefore, this study aimed to compare the incidence of PFF and stem subsidence in patients undergoing THA between two types of cementless femoral component. Methods: Between January 2013 and June 2020, 753 primary cementless THAs using a fit-and-fill stem and 526 using a tapered-wedge stem were performed at our institution. The patient’s background characteristics, radiographic findings, and perioperative complications were compared using univariate, multivariate, and propensity score analyses, matching sex, age, body mass index, and femoral morphology (Dorr type) between the two groups. Results: In the univariate analyses, the rates of perioperative PFF and ≥ 2-mm stem subsidence were significantly higher in the fit-and-fill stem group than in the tapered-wedge group ( P = 0.290 and P = 0.0001, respectively). The mean age and proportion of female in the fit-and-fill stemgroup were also significantly higher than those in the tapered-wedge group ( P = 0.0274 and 0.0009, respectively). Four hundred and seventy-eight THAs were extracted from both groups on the basis of propensity score matching. After matching, the rates of perioperative PFF and ≥2-mm stem subsidence in the fit-and-fill stem and tapered-wedge stem groups were 2.3% and 0.6%, and 7.2% and 1.5%, respectively. The rate of PFF was significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group ( P = 0.0264; 95% confidence interval [CI]: 1.0–13.5, odds ratio [OR]: 3.7), and the same results was observed for ≥2-mm stem subsidence ( P = 0.0001; 95% CI: 2.2–11.7, OR: 5.2). Conclusion: Tapered-wedge stem is more suitable for any age, gender, and type of physique or femoral morphology than the fit-and-fill stem to avoid early perioperative complications, such as a PFF and stem subsidence in cementless THA. Health sciences/Medical research Health sciences/Risk factors Total hip arthroplasty Periprosthetic femoral fracture Stem subsidence Fit-and-fill stem Tapered-wedge stem Propensity score matching analysis Figures Figure 1 Figure 2 Figure 3 Introduction In orthopedic surgery, total hip arthroplasty (THA) is one of the most common and successful methods of treating patients with hip osteoarthritis (OA) of various etiologies [ 1 – 6 ]. Owing to demographic changes, the indications for THA have expanded. Periprosthetic femoral fractures (PFFs) after THA are devastating complications associated with functional limitations and increased overall mortality [ 7 ]. Outcomes were worse in patients with revision THA for a PFF than in reference patients (revision THA for aseptic loosening). A higher 6-month mortality rate (7.3%) was observed in patients with PFF than in those without (0.9%) [ 7 ]. Although cementless implants have been associated with an increased risk of PFF, the precise contribution of implant geometry and design to the risk of intraoperative and postoperative PFF remains poorly investigated. Stem subsidence, like PFF, instability, and infection, is a cause of early surgical failure [ 8 – 10 ]. Maximum stem subsidence was observed within the first 6–8 weeks after cementless THA [ 11 – 13 ]. This can lead to unequal leg length, decreased hip stability, and implant failure [ 14 , 15 ]. Several studies have revealed a relationship between stem subsidence and survival [ 16 – 20 ]. Streit et al. demonstrated the survivorship would decrease to 29% if subsidence was > 2.7 mm [ 20 ]. Therefore, a number of studies have reported on PFF and stem subsidence following THA. Age, sex, body mass index (BMI), bone morphology, and femoral stem type have been reported as risk factors for PFF or stem subsidence [ 21 – 29 ]. However, few reports have focused on perioperative PFF and stem subsidence after THA with a comparison different femoral component designs at a single center in a population with matching with characteristics or bone morphology. Therefore, this study aimed to compare the incidence of PFF and stem subsidence between two types of cementless femoral components in patients undergoing THA using propensity score matching. Materials and methods This study was approved by our institutional review board. It was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all patients prior to study. Study Design and Population Seven hundred fifty-three primary cementless THAs using a conventional fit-and fill stem (Fig. 1 a; PerFix910, Kyocera, Kyoto, Japan) and 526 primary cementless THAs using a modern tapered-wedge stem (Fig. 1 b; Initia, Kyocera, Kyoto, Japan) were performed using the posterolateral approach at our institution between January 2013 and June 2020. Five experienced hip surgeons performed the operations, each with > 50 THAs/year of experience. At our institution, a conventional fit-and-fill stem is used for the cementless THA. However, since August 2017, we have been using a modern tapered-wedge stems for various types of femoral morphologies in THA. Therefore, the choice of stem type was based on its historical usage. Data Collection Age, sex, BMI, basic diseases, and history of femoral osteotomy were investigated. Stem sizes, and offset (standard or high) were recorded from surgical records. Radiologically, the Dorr, Crowe, and Bombelli classifications, neck-shaft angle, and femoral bowing (anteroposterior [AP] and lateral views) were evaluated using preoperative radiographs [ 30 – 33 ]. Postoperative radiographs were assessed by two observers (S.I. and K.S.), who are orthopedic surgeons with extensive diagnostic imaging experience, using a digital imaging system (Synapse Digital Imaging System; Fujifilm Medical Imaging, Tokyo, Japan); only mean values were used in statistical analysis. Alignment of the inserted femoral component was classified as varus, valgus, or neutral in AP radiographs, and as extension, flexion, or neutral in lateral radiographs. An angle > 3° was defined as positive for all parameters [ 15 ]. Subsidence was defined as a femoral stem distalization in reference to the major trochanter, according to a previous report [ 15 ]. The distance between the apex of the major trochanter and the stem shoulder was measured at three different time points (immediately [0 W], 1 week [1 W], and 6 weeks [6 W] postoperatively), and the degree of stem subsidence was assessed by comparing the distance at each time point (0 W versus [vs.] 1 W, 1 W vs. 6 W, and 0 W vs. 6 W) in both stems. Substantial stem subsidence was defined as ≥ 2 mm according to previous studies [ 34 , 35 ]. We standardized the rotation of the lower limbs on AP radiographs by positioning both patellae in an exact frontal position throughout the radiological examination. Postoperative PFF was evaluated using both AP radiography and computed tomography (CT), whereas intraoperative PFF was investigated using surgical records. Statistical Analysis Statistical analyses were performed using univariate, multivariate, and propensity score matching analyses (Fig. 2 ). The chi-square or Fisher exact probability test was used to compare sex; basic disease; previous history of femoral osteotomy; Dorr, Crowe, and Bombelli classifications; neck offset (standard/high offset); the presences of PFF and stem subsidence (≥ 2mm); and other postoperative complications including dislocation or deep infection between the fit-and-fill and tapered-wedge stem groups. Age, BMI, neck-shaft angle, femoral bowing, and degree of stem subsidence were compared between the two groups using the unpaired t -test. Multivariate analysis was performed to identify the parameters associated with PFF or stem subsidence using stepwise logistic regression with the variable selection ( P < 0.2). Patients who underwent THA using tapered-wedge stem were matched to those who underwent THA using a fit-and-fill stem at a ratio of 1:1 by greedy matching on the logit of propensity scores with a caliper of 0.2x the standard deviation (SD) [ 36 ]. Age at the time of surgery, sex, BMI, and Dorr type were included as confounders when calculating the propensity score using multivariate logistic regression analysis for each patient. The patients were matched using the nearest-neighbor technique, and propensity score matching was performed between the 478 fit-and-fill stems 478 tapered-wedge stems. All statistical analyses were performed using JMP software (version 9.0.1; SAS Institute Inc., Cary, NC, USA), and statistical significance was set at P < 0.05. Results Patients Demographics The detailed patient characteristics are presented in Table 1 . The fit-and-fill stem group included 116 males and 637 females with a mean age at surgery of 65.6 years (SD: 10.9). The tapered-wedge stem group included 106 males and 420 females with a mean age of 63.4 years (SD: 12.4). There were significant differences in sex and age between the groups ( P = 0.0009 and 0.0274, respectively). The mean BMI values were 24.2 kg/m 2 (SD: 3.9) in the fit-and-fill stem group, and 24.0 kg/m 2 (SD: 4.0) in the tapered-wedge stem group, showing no significant difference between the two groups ( P = 0.4367). The reasons for surgery included 691 hips with OA; 56 with osteonecrosis of the femoral head (ONFH), and six with rheumatoid arthritis (RA) in the fit-and-fill stem group and 428 with OA, 90 with ONFH, and eight with RA in the tapered-wedge stem group. These reasons were significantly different between the groups ( P = 0.0001). There was also a significant difference in the history of femoral osteotomy between the groups ( P = 0.0357). Regarding bone morphology, there were significant differences in AP femoral bowing and the Bombelli classification ( P = 0.0001 and P = 0.0150, respectively). Table 1 Results of univariate analyses of cohort characteristics and bone morphologies Fit-and-fill stem group Tapered-wedge stem group P value (n = 753) (n = 526) Cohort characteristics Age (years) 65.6 ± 10.9 63.4 ± 12.4 0.0009* Sex (male: female) 116: 637 (85%: 15%) 106: 420 (80%: 20%) 0.0274 BMI (kg/m 2 ) 24.2 ± 3.9 24.0 ± 4.0 0.4367 Diagnosis 0.0001 OA 691 428 Other (ONFH or RA) 62 98 History of femoral osteotomy 43 (5.7%) 17 (3.2%) 0.0357 Bone morphologies Neck-shaft angle (◦) 133.2 ± 7.2 133.7 ± 7.2 0.1979 AP bowing (◦) 0.7 ± 1.4 1.2 ± 1.8 0.0001 Bombelli classification (A/N/H) 95/485/172 (13%/64%/23%) 92/339/95 (17%/65%/18%) 0.0150 Crowe classification (1/2/3/4) 678/50/20/5 (90%/6.6%/2.7%/0.7%) 477/31/15/3 (90.7%/5.8%/2.9%/0.6%) 0.9452 Dorr classification (A/B/C) 244/462/47 (32%/61%/7%) 165/318/43 (31%/61%/8%) 0.4131 Continuous variables are represented as mean ± standard deviation. Abbreviations: n, number; BMI, body mass index; OA, osteoarthritis; ONFH, osteonecrosis of the femoral head; RA, rheumatoid arthritis; AP, anteroposterior; A, atrophic; N, normal; H, hypertrophic * P < 0.05 indicates significance The surgical factors and perioperative complications are shown in Table 2 . The rate of stem insertion with extension or flexion in the tapered-wedge stem group (20.5%) was significantly higher than that in the fit-and-fill stem group (13.9%) ( P = 0.0001), owing to the high degree of freedom of stem insertion in the tapered-wedge stem. PFF was observed in 18 patients (2.4%) in the fit-and-fill stem group. Among them, seven had intraoperative PFF and 11 were postoperative PFF. Vancouver type A G fracture was present in 15 cases and type B 2 fracture in three cases. Conservative treatment was initiated in 13 patients, and five patients underwent a second surgery (three revision THAs [Fig. 3 ] and two osteosynthesis). In contrast, PFF was observed in only four patients (0.8%) in the tapered-wedge stem group. All four patients had postoperative Vancouver Type A G fractures; thus, they were treated conservatively. There was significant difference in the rate of PFF between the groups ( P = 0.0290). Table 2 Results of univariate analyses of surgical factors and perioperative complications Fit-and-fill stem group Tapered-wedge stem group P value (n = 753) (n = 526) Surgical factors Varus or valgus stem insertion on AP view (°) 0.44 ± 0.03 0.49 ± 0.04 0.3173 > 3° of varus or valgus stem insertion on AP view 29 (3.8%) 20 (3.8%) 0.9642 Flexion or extension stem insertion on lateral view (°) 0.82 ± 1.26 1.16 ± 1.58 0.0001 > 3° of flexion or extension stem insertion on lateral view 92 (13.9%) 108 (20.5%) 0.0001 STD/HO 3%/97% 51%/49% 0.0001 Perioperative complications Dislocation 9 (1.2%) 4 (0.7%) 0.5759 Infection 0 2 (0.4%) 0.1689 PFF 18 (2.4%) 4 (0.8%) 0.0290 Intraoperative/postoperative 7/11 0/4 Vancouver classification Type A G : 15, Type B 2 : 3 Type A G : 4 Treatment (surgical/conservative) 5/13 0/4 Methods of surgical treatment Stem revision: 3, Plating: 2 - Stem subsidence (mm) Duration from 0 W to 6 W 0.50 ± 2.4 0.24 ± 0.6 0.0177 ≥ 2-mm subsidence 79 (10.5%) 10 (1.9%) 0.0001 1 W to 6 W 0.25 ± 2.1 0.11 ± 0.6 0.1295 ≥ 2-mm subsidence 54 (7.2%) 8 (1.5%) 0.0001 Abbreviations: STD, standard; HO, high-offset; PFF; periprosthetic femoral fracture, 0W, immediate after surgery; 1W, 1 week after the surgery; 6W, 6 weeks after surgery The mean degree of stem subsidence from 0–6 W was significantly higher in the fit-and-fill stem group than in the tapered-wedge stem group. The rates of ≥ 2-mm stem subsidence from 0–6 W and 1–6 W were significantly higher in the fit-and-fill stem group (10.5% and 7.2%, respectively) than in the tapered-wedge stem group (1.9% and 1.5%, respectively) ( P = 0.0001 for both). Regarding other early postoperative complications, dislocation was observed in nine patients (1.2%) of the fit-and-fill stem group, whereas that was observed in four patients (0.7%) of the tapered-wedge stem group. Deep infection was observed only in two patients (0.4%) of the tapered-wedge stem group. There were no significant differences in the rates of dislocation or deep infection between the groups ( P = 0.5759 and P = 0.1689, respectively). Multivariate analysis demonstrated that older age, previous history of osteotomy, and fit-and-fill stem were independently associated with PFF (Table 3 , P = 0.00808, 0.00222, and 0.03699, respectively) and that older age and fit-and-fill stem were independently associated with ≥ 2-mm subsidence after THA (Table 3 , P = 0.03870 and P < 0.0001, respectively) Table 3 Independent factors associated with PFF and ≥ 2-mm stem subsidence after THA in multivariate analyses Parameter Odds Ratio 95% CI P value PFF Older age 1.06 1.01–1.11 0.00808 Previous history of femoral osteotomy 7.35 2.42–22.27 0.00222 Fit-and-fill stem 2.91 1.00–8.80 0.03699 Stem valgus insertion 2.27 0.81–6.31 0.13157 Stem flexion insertion 2.26 0.85–6.04 0.09617 ≥ 2-mm stem subsidence Older age 1.02 1.00–1.04 0.03870 Male 1.51 0.86 − 2.65 0.13721 Bombelli classification (atrophic) 1.51 0.83–2.75 0.19101 Fit-and-fill stem 6.32 3.22–12.40 90%) who underwent THA using a tapered-wedged stem were matched to patients who underwent THA using a fit-and-fill stem, with standardized differences of < 10% for four covariates (age, sex, BMI, and Dorr type), indicating an adequate match (Table 4 ). After matching, the rates of perioperative PFF and ≥ 2-mm stem subsidence in the fit-and-fill stem and tapered-wedge stem groups were 2.3% and 0.6%, and 7.2% and 1.5%, respectively. The rate of PFF was significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group ( P = 0.0264; 95% confidence interval [CI]: 1.0–13.5, odds ratio [OR]: 3.7), and the same results was observed for ≥ 2-mm stem subsidence ( P = 0.0001; 95% CI: 2.2–11.7, OR: 5.2). Table 4 Comparison of PFF and ≥ 2-mm stem subsidence after THA between the fit-and-fill and tapered-wedge stem groups using propensity score matching. Fit-and-fill stem (n = 478) Tapered wedge stem (n = 478) Odd Ratio 95% CI P value Age (years) 65.1 ± 11.3 64.9 ± 11.0 n/a n/a 0.7800 Sex (male: female) 84%/16% 85%/15% n/a n/a 0.4791 BMI (Kg/m 2 ) 24.1 ± 3.8 24.0 ± 4.0 n/a n/a 0.5927 Dorr classification (A/B/C) 32%/60%/8% 32%/61%/7% n/a n/a 0.9179 PFF 11 (2.3%) 3 (0.6%) 3.7 1.0–13.5 0.0264 ≥ 2-mm stem subsidence 0 W to 6 W 56 (11.7%) 9 (1.9%) 6.9 3.4–14.2 0.0001 1 W to 6 W 34 (7.2%) 7 (1.5%) 5.2 2.2–11.7 0.0001 Abbreviation: n/a, not applicable Discussion Previous studies reported that age, sex, BMI, and bone morphology, e.g., Dorr type, are essential parameters for PFF and stem subsidence [ 21 – 29 ]. A PFF is well recognized as a severe complication of THA. The functional outcome (Oxford 12 hip score) of 232 patients who underwent revision THA for the treatment of PFF was significantly worse than that of 232 patients who underwent revision THA for the treatment of aseptic loosening [ 7 ]. Additionally, a higher mortality rate (7.3%) 6 months after revision THA in patients with PFF than in those with aseptic loosening (0.9%) [ 7 ]. Age is frequently cited as a risk factor of PFF. Franklin et al. reviewed 16 fractures out of 454 cementless THA and found a significant association between an elevated risk of fracture and patient age [ 24 ]. A single-center investigation of > 6000 cases of primary cementless THA reported that female sex, BMI 65 years were independent risk factors for PFF [ 22 ]. Similarly, in our study, the fit-and-fill stem group, which had a significantly higher incidence of perioperative periprosthetic fractures, included a higher proportion of older and female patients than the tapered wedge stem group. A previous history of femoral osteotomy has also been reported as a risk factor for PFF. Ohishi et al. investigated the incidence of PFF during total hip arthroplasty (THA) in patients with a history of femoral osteotomy, reporting a higher rate of 4 out of 66 cases (6.1%) compared to THA without a history of osteotomy [ 37 ]. The reasons for the higher incidence of periprosthetic femoral fractures in cases following femoral osteotomy include severe proximal femoral deformity and sclerotic calcar. In our current study, multivariate analysis also identified a history of femoral osteotomy as a significant risk factor for periprosthetic femoral fractures. To evaluate differences in the risk of PFF between stem types, cases with a history of femoral osteotomy were excluded in the propensity score matching. Subsidence is a known complication of THA. Walker et al. reported that subsidence of the femoral stem can predict clinical outcomes and that decreased subsidence leads to better results [ 16 ]. In addition, considerable subsidence may contribute to postoperative instability and leg length discrepancy [ 14 , 15 ]. Radiographic analysis revealed substantial stem subsidence in 52 of 180 patients (28.9%). In the multivariate analysis, older age was an independent risk factor for early stem subsidence [ 38 ]. Johanson et al. revealed that male sex was an independent risk factor for stem subsidence [ 39 ], and Reinbacher et al. reported a higher risk for subsidence in male and overweight patients after THA using a short femoral cementless stem [ 29 ]. Several studies have reported that overweight or obesity is a significant risk factor for stem subsidence. Physical patient characteristics, e.g., body weight > 75kg, substantially influenced stem subsidence after cementless THA [ 40 ]. A large study of 502 hips treated with primary THA using a cementless stem found that the average subsidence of the stem at the final follow-up was 2.2 mm [ 26 ]. Of these, 17.3% had considerable subsidence (> 5 mm). Most cases of stem subsidence occur within 3–6 months after surgery, and femoral stem subsidence was associated with BMI (> 25 kg/m 2 ) [ 26 ]. Song et al. investigated the subsidence of a collarless hydroxyapatite (HA)-coated stem [ 28 ]. Their study demonstrated that Dorr type C femoral bone had a higher risk of subsidence when uncemented collarless HA-coated stems were used [ 28 ]. Therefore, this study compared the rate of PFF and stem subsidence between the fit-and-fill stem and tapered-wedge stem groups after matching for age, sex, BMI, and Dorr type to assess the influence of stem design. There have been few reports on PFF and stem subsidence comparing different types of stems at a single center. Sershon et al. compared the PFF of cementless fit-and-fill stems (metaphyseal filling) with that of cementless single-wedge tapered-wedge stems [ 22 ]. They reported that the PFF rate was 1.41% and that single-wedge tapered stem types were more prone to PFF than fit-and-fill designs [ 22 ]. Grant et al. compared the subsidence of a cementless fit-and-fill stem to that of a cementless tapered-wedge stem [ 21 ]. The mean degree of subsidence 4 weeks after THA was significantly lower in 65 patients treated with a tapered-wedge stem (0.3 mm) than in 61 patients treated with a fit-and-fill stem (1.1 mm), which was consistent with our results (taper wedge, 0.24 mm; fit-and-fill, 0.50 mm). However, these studies compared the rate of PFF or stem subsidence between two types of cementless stems without matching for age, sex, BMI, and bone morphology, e.g., Dorr type. Therefore, the purpose of our study was to unify these factors and examine the effects of stem design on the rate of PFF and stem subsidence. Here, the rates of PFF and ≥ 2-mm of stem subsidence were significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group. Thus, this is the first report on severe perioperative complications, such as PFF and stem subsidence, in THA using cementless stems that matched patient background characteristics including age, sex, BMI, and Dorr type with respect to the stem type. Regarding the lower rate of PFF and stem subsidence in the tapered-wedge stem group than in the fit-and-fill stem group observed in our study, a recent comparative study mentioned that tapered-wedge stems are designed to achieve a more congruent cortical fit in the coronal plane and have demonstrated excellent long-term results over 25 years, with a low loosening rate (1.4%) [ 21 , 41 ]. We consider that the mediolateral cortical bone quality at the level of initial fixation in the tapered-wedge stem (bellow the lesser trochanter) is better than that in the fit-and-fill stem (above the lesser trochanter) in most femurs, which may be related to the differences in the degree of PFF and stem subsidence between the study groups. Additionally, the fit-and-fill stem required reaming and broaching, whereas the tapered-wedge stem required only broaching. This difference in surgical steps might also affect the frequency of PFF occurrence. There were several limitations to the current study. First, this study was not prospective and randomized. Therefore, the precise effect of the type of stem on PFF or subsidence after THA should be further confirmed in a randomized controlled study. Second, this study evaluated stem subsidence only early (up to 6 W) after surgery in both fit-and-fill and tapered-wedge stems, although Dalury et al. reported that subsidence was apparent at 6 weeks and remained stable at an average of 6 years of follow-up [ 42 ]. Finally, the implants used in this study are not commonly used globally. In conclusion, a tapered-wedge stem is more suitable than a fit-and-fill stem for any age, sex, and type of physique or femoral morphology to avoid early perioperative complications, such as PFF and stem subsidence, in cementless THA. Abbreviations THA, total hip arthroplasty; OA, osteoarthritis; PFF, periprosthetic femoral fracture; ONFH, osteonecrosis of the femoral head; BMI, body mass index; AP, anteroposterior; CT, computed tomography; vs., versus; SD, standard deviation; CI, confidence interval; OR, odds ratio; RA, rheumatoid arthritis; HA, hydroxyapatite Declarations Acknowledgements Not applicable Authors’ contributions SI performed the literature review and drafted the manuscript. YN supervised writing of the manuscript. SI, KS, GM, SH, MF, SK, TS, RY, DH, and TU contributed to the data collection. SI and KS analyzed the data. All authors read and approved the final manuscript. Funding This work was supported in part by a Grant-in-Aid in Scientific Research (No. JP19K09628) from the Japan Society for the Promotion of Science. Availability of data and materials The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. Ethics approval and consent to participate This retrospective study was approved by Kyushu University institutional review board for clinical research (NO. 30-91). Written informed consent was obtained from all patients prior to study. Consent for publication Not applicable Competing interests The authors declare that they have no competing interests. References Nowak, M., Kusz, D., Wojciechowski, P. & Wilk, R. Risk factors for intraoperative periprosthetic femoral fractures during the total hip arthroplasty. Pol. Orthop. Traumatol. 77 , 59–64 (2012). Hagel, A., Siekmann, H. & Delank, K. S. Periprosthetic femoral fracture- an interdisciplinary challenge. Dtsch. Arztebl Int. 111 , 658–664 (2014). Koenig, K., Huddleston, J. I. 3rd, Huddleston, H., Maloney, W. J. & Goodman, S. B. Advanced age and comorbidity increase the risk for adverse events after revision total hip arthroplasty. J. Arthroplasty . 27 , 1402–1407 (2012). Dumont, G. D., Zide, J. R. & Huo, M. H. Periprosthetic Femur Fractures: Current Concepts and Management. YSART 21 , 9–13 (2010). Masri, B. A., Meek, R. M. D. & Duncan, C. P. Periprosthetic fractures evaluation and treatment. Clin. Orthop. Relat. Res. 420 , 80–95 (2004). Schwarzkopf, R., Oni, J. K. & Marwin, S. E. Total hip arthroplasty periprosthetic femoral fractures: a review of classifica tion and current treatment. Bull. Hosp. Jt. Dis. 71 , 68–78 (2013). Young, S. W., Walker, C. G. & Pitto, R. P. Functional outcome of femoral peri prosthetic fracture and revision hip arthroplasty: a matched-pair study from the New Zealand Registry. Acta Orthop. 79 , 483–488 (2008). Kärrholm, J., Borssén, B., Löwenhielm, G. & Snorrason, F. Does early micromotion of femoral stem prostheses matter? 4–7-year stereoradiographic follow-up of 84 cemented prostheses. J. Bone Joint Surg. Br. 76 , 912–917 (1994). Campbell, D. et al. Early migration characteristics of a hydroxyapatite-coated femoral stem: an RSA study. Int. Orthop. 35 , 483–488 (2011). Gwam, C. U. et al. Current epidemiology of revision total hip arthroplasty in the United States: National Inpatient Sample 2009 to 2013. J. Arthroplasty . 32 , 2088–2092 (2017). Al-Najjim, M., Khattak, U., Sim, J. & Chambers, I. Differences in subsidence rate between alternative designs of a commonly used uncemented femoral stem. J. Orthop. 13 , 322–326 (2016). Ström, H., Nilsson, O., Milbrink, J., Mallmin, H. & Larsson, S. Early migration pattern of the uncemented CLS stem in total hip arthroplasties. Clin. Orthop. Relat. Res. 454 , 127–132 (2007). Selvaratnam, V., Shetty, V. & Sahni, V. Subsidence in collarless Corail hip replacement. Open. Orthop. J. 29 , 194–197 (2015). Sudhahar, T. A., Morapudi, S. & Branes, K. Evaluation of subsidence between collarless and collared Corail femoral cement less total hip replacement. J. Orthop. 6 , e3 (2009). Ries, C., Boese, C. K., Dietrich, F., Miehlke, W. & Heisel, C. Femoral stem subsidence in cementless total hip arthroplasty: a retrospective single-centre study. Int. Orthop. 43 , 307–314 (2019). Walker, P. S., Mai, S. F., Cobb, A. G., Bentley, G. & Hua, J. Prediction of clinical outcome of THR from migration measurements on standard radiographs. A study of cemented Charnley and Stanmore femoral stems. J. Bone Joint Surg. Br. 77 , 705–714 (1995). Karrholm, J., Borssen, B., Lowenhielm, G. & Snorrason, F. Does early micromotion of femoral stem prostheses matter? 4-7-year stereoradiographic follow-up of 84 cemented prostheses. J. Bone Joint Surg. Br. 76 , 912–917 (1994). Kobayashi, A., Donnelly, W. J., Scott, G. & Freeman, M. A. Early radiological observations may predict the long-term survival of femoral hip prostheses. J. Bone Joint Surg. Br. 79 , 583–589 (1997). Kroell, A. et al. Aseptic stem loosening in primary THA: migration analysis of cemented and cementless fixation. Int. Orthop. 33 , 1501–1505 (2009). Streit, M. R. et al. Early migration predicts aseptic loosening of cementless femoral stems: a long-term study. Clin. Orthop. Relat. Res. 474 , 1697–1706 (2016). Grant, T. W. et al. Cementless Tapered Wedge Femoral Stems Decrease Subsidence in Obese Patients Compared to Traditional Fit-and-Fill Stems. J. Arthroplasty . 32 , 891–897 (2017). Sershon, R. A., McDonald, J. F. 3rd, Ho, H. & Hamilton, W. G. Periprosthetic Femur Fracture Risk: Influenced by Stem Choice, Not Surgical Approach. J. Arthroplasty . 36 , S363–S366 (2021). Berend, K. R. & Lombardi, A. V. Jr Intraoperative femur fracture is associated with stem and instrument design in primary total hip arthroplasty. Clin. Orthop. Relat. Res. 468 , 2377–2381 (2010). Franklin, J. & Malchau, H. Risk factors for periprosthetic femoral fracture. Injury 38 , 655–660 (2007). Gromov, K. et al. Risk factors for post-operative periprosthetic fractures following primary total hip arthroplasty with a proximally coated double-tapered cementless femoral component. Bone Joint J. 99-B , 451–457 (2017). Bornes, T. D. et al. Subsidence of a Single-Taper Femoral Stem in Primary Total Hip Arthroplasty: Characterization, Associated Factors, and Sequelae. J. Arthroplasty . 38 , S174–S178 (2023). Leiss, F. et al. Differences in femoral component subsidence rate after THA using an uncemented collarless femoral stem: full weight–bearing with an enhanced recovery rehabilitation versus partial weight–bearing. Arch. Orthop. Trauma. Surg. 142 , 673–680 (2022). Song, J. H. et al. Subsidence and perioperative periprosthetic fractures using collarless hydroxyapatite-coated stem for displaced femoral neck fractures according to Dorr type. J. Orthop. Surg. (Hong Kong) . 27 , 2309499019877530 (2019). Reinbacher, P. et al. Three-year migration analysis of a new metaphyseal anchoring short femoral stem in THA using EBRA-FCA. Sci. Rep. 12 , 17173 (2022). Dorr, L. D. et al. Structural and cellular assessment of bone quality of proximal femur. Bone 14 , 231–242 (1993). Clavé, A. et al. Influence of experience on intra- and inter-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classifications. Orthop. Traumatol. Surg. Res. 102 , 155–159 (2016). Okano, K., Aoyagi, K., Chiba, K., Motokawa, S. & Matsumoto, T. Bone mineral density is not related to osteophyte formation in osteoarthritis of the hip. J. Rheumatol. 38 , 358–361 (2011). Akiyama, K. & Shibuya, T. Influence of femoral bowing on range of motion after total hip arthroplasty. Int. Orthop. 42 , 1795–1802 (2018). Engh, C. A., Bobyn, J. D. & Glassman, A. H. Porous-coated hip replacement. The factors governing bone ingrowth, stress shielding, and clinical results. J. Bone Joint Surg. Br. 69 , 45–55 (1987). Tyrpenou, E. et al. A Large-Scale Fifteen-Year Minimum Survivorship of a Cementless Triple Tapered Femoral Stem. J. Arthroplasty . 35 , 2161–2166 (2020). Bangalore, S. et al. Everolimus-eluting stents or bypass surgery for multivessel coronary disease. N Engl. J. Med. 372 , 1213–1222 (2015). Ohishi, M. et al. Cementless total hip arthroplasty for patients previously treated with femoral osteotomy for hip dysplasia: the incidence of periprosthetic fracture. Int. Orthop. 40 , 1601–1606 (2016). Lo, I. N. et al. Initial femoral stem position in cementless bipolar hemiarthroplasty for femoral neck fracture in elderly patients is associated with early implant subsidence: A radiographic analysis. Injury 52 , 1801–1806 (2021). Johanson, P. E., Antonsson, M., Shareghi, B. & Kärrholm, J. Early Subsidence Predicts Failure of a Cemented Femoral Stem With Minor Design Changes. Clin. Orthop. Relat. Res. 474 , 2221–2229 (2016). Stihsen, C., Radl, R., Keshmiri, A., Rehak, P. & Windhager, R. Subsidence of a cementless femoral component influenced by body weight and body mass index. Int. Orthop. 36 , 941–947 (2012). McCalden, R. W., Korczak, A., Somerville, L., Yuan, X. & Naudie, D. D. A randomised trial comparing a short and a standard-length metaphyseal engaging cementless femoral stem using radiostereometric analysis. Bone Joint J. 97 , 595–600 (2015). Dalury, D. F., Kelley, T. C. & Adams, M. J. Modern proximally tapered uncemented stems can be safely used in Dorr type C femoral bone. J. Arthroplasty . 27 , 1014–1018 (2012). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 09 Oct, 2025 Reviews received at journal 02 Oct, 2025 Reviewers agreed at journal 02 Oct, 2025 Reviewers agreed at journal 04 Sep, 2025 Reviews received at journal 01 Aug, 2025 Reviews received at journal 17 Jul, 2025 Reviewers agreed at journal 09 Jul, 2025 Reviewers agreed at journal 09 Jul, 2025 Reviewers invited by journal 08 May, 2025 Editor assigned by journal 06 May, 2025 Editor invited by journal 17 Jan, 2025 Submission checks completed at journal 16 Jan, 2025 First submitted to journal 13 Jan, 2025 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. 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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-5822802","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":403603553,"identity":"bf42c417-5e03-477a-911a-b7ab5f3811b3","order_by":0,"name":"Satoshi Ikemura","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2ElEQVRIiWNgGAWjYFACxmYIzd4AJAwsSNHCcwCkRYIoa5ghlEQCmCSsXr79cLPBx5zD+fwzn1/d8KNAgoG/vTsBrxaDM4nNiTO3HbaccTun7GYP0GESZ85uwK+FIbH5MO+2wwYMt3PSbvAAtRhI5OLXIt//sPnwX6AW+Ztn0m7+IUYLw43E5mRGoBaDG+zHbhNli8GNh82GvdvSDQzP5LDdljGQ4CHoF/n+9McSP7dZG8gdP/7s5ps/NnL87b0EHIYAPAZgkljlIMD+gBTVo2AUjIJRMIIAAIEoSt1DOVOHAAAAAElFTkSuQmCC","orcid":"","institution":"Kyushu University","correspondingAuthor":true,"prefix":"","firstName":"Satoshi","middleName":"","lastName":"Ikemura","suffix":""},{"id":403603555,"identity":"c9dfa28c-a571-4855-bd70-764ecfe702f8","order_by":1,"name":"Kyohei Shiomoto","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Kyohei","middleName":"","lastName":"Shiomoto","suffix":""},{"id":403603558,"identity":"5f2db8b5-b550-4734-83e8-5cce91eb76d9","order_by":2,"name":"Goro Motomura","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Goro","middleName":"","lastName":"Motomura","suffix":""},{"id":403603559,"identity":"d8668b5a-4e41-4dd4-b605-7bf71e7831d7","order_by":3,"name":"Satoshi Hamai","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Satoshi","middleName":"","lastName":"Hamai","suffix":""},{"id":403603561,"identity":"0f6ee450-32f6-4264-a32b-9200bc03df83","order_by":4,"name":"Masanori Fujii","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Masanori","middleName":"","lastName":"Fujii","suffix":""},{"id":403603562,"identity":"fea438e8-1a4f-4cf1-a9c8-a171baf177f5","order_by":5,"name":"Shinya Kawahara","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Shinya","middleName":"","lastName":"Kawahara","suffix":""},{"id":403603563,"identity":"9bf3d762-2e61-4d6c-9d70-d8d73678b6f5","order_by":6,"name":"Taishi Sato","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Taishi","middleName":"","lastName":"Sato","suffix":""},{"id":403603564,"identity":"d99b0c80-8538-4cfb-9a12-71e3e9b54793","order_by":7,"name":"Ryosuke Yamaguchi","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Ryosuke","middleName":"","lastName":"Yamaguchi","suffix":""},{"id":403603565,"identity":"e35f64e4-27a8-4053-8cb4-4917e52c5126","order_by":8,"name":"Daisuke Hara","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Daisuke","middleName":"","lastName":"Hara","suffix":""},{"id":403603566,"identity":"be360bf0-736e-4ae0-9288-f9b52568a466","order_by":9,"name":"Takeshi Utsunomiya","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Takeshi","middleName":"","lastName":"Utsunomiya","suffix":""},{"id":403603567,"identity":"9f0f9037-f586-43c6-b1a8-4c7d725f3082","order_by":10,"name":"Yasuharu Nakashima","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Yasuharu","middleName":"","lastName":"Nakashima","suffix":""}],"badges":[],"createdAt":"2025-01-13 22:23:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5822802/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5822802/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":74410564,"identity":"7bfbb261-fd10-46c3-9d63-cfde0c48d6d5","added_by":"auto","created_at":"2025-01-22 05:36:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":437282,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea\u003c/strong\u003e.\u003cstrong\u003e \u003c/strong\u003eCoronal and sagittal profile of Fit-and-fill stem (PerFix910; Kyocera, Kyoto, Japan). STD, standard offset; HO, high offset. \u003cstrong\u003eb\u003c/strong\u003e. Coronal and sagittal profile of tapered wedge stem (Initia; Kyocera, Kyoto, Japan).\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-5822802/v1/0bdde052d13260591c3a4381.png"},{"id":74412658,"identity":"9b3848ec-cdea-4529-9614-6ae5f5ac4a92","added_by":"auto","created_at":"2025-01-22 06:00:11","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":180904,"visible":true,"origin":"","legend":"\u003cp\u003eSample selection flow diagram illustrating patients who underwent THA and were included in this study. THA, total hip arthroplasty; BMI, body mass index.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-5822802/v1/e8f990fc7fd256f6d4ff342f.png"},{"id":74410565,"identity":"203cfcca-9b73-4db4-93c0-991e8ca65d19","added_by":"auto","created_at":"2025-01-22 05:36:11","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":940802,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea. \u003c/strong\u003eA\u003cstrong\u003e \u003c/strong\u003e73-year-old female with advanced osteoarthritis was treated by cementless total hip arthroplasty (THA) using a fit-and-fill stem. \u003cstrong\u003eb.\u003c/strong\u003e A periprosthetic femoral fracture (PFF) is observed 3 weeks postoperatively without any antecedent trauma. \u003cstrong\u003ec.\u003c/strong\u003eRevision surgery was performed using the cementless long stem with distal screws.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-5822802/v1/0df2d336e55c48ad4edb8ea3.png"},{"id":74412683,"identity":"1bdc7773-8629-4b07-860d-69624ba12e3d","added_by":"auto","created_at":"2025-01-22 06:00:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2863158,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5822802/v1/7f08005e-9ae0-436e-93b0-25269bbbb726.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of early periprosthetic femoral complications following cementless total hip arthroplasty between fit-and-fill stems and tapered-wedge stems: a propensity score matching study from a single center","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn orthopedic surgery, total hip arthroplasty (THA) is one of the most common and successful methods of treating patients with hip osteoarthritis (OA) of various etiologies [\u003cspan additionalcitationids=\"CR2 CR3 CR4 CR5\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Owing to demographic changes, the indications for THA have expanded. Periprosthetic femoral fractures (PFFs) after THA are devastating complications associated with functional limitations and increased overall mortality [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Outcomes were worse in patients with revision THA for a PFF than in reference patients (revision THA for aseptic loosening). A higher 6-month mortality rate (7.3%) was observed in patients with PFF than in those without (0.9%) [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Although cementless implants have been associated with an increased risk of PFF, the precise contribution of implant geometry and design to the risk of intraoperative and postoperative PFF remains poorly investigated.\u003c/p\u003e \u003cp\u003eStem subsidence, like PFF, instability, and infection, is a cause of early surgical failure [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Maximum stem subsidence was observed within the first 6\u0026ndash;8 weeks after cementless THA [\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. This can lead to unequal leg length, decreased hip stability, and implant failure [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Several studies have revealed a relationship between stem subsidence and survival [\u003cspan additionalcitationids=\"CR17 CR18 CR19\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Streit et al. demonstrated the survivorship would decrease to 29% if subsidence was \u0026gt;\u0026thinsp;2.7 mm [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTherefore, a number of studies have reported on PFF and stem subsidence following THA. Age, sex, body mass index (BMI), bone morphology, and femoral stem type have been reported as risk factors for PFF or stem subsidence [\u003cspan additionalcitationids=\"CR22 CR23 CR24 CR25 CR26 CR27 CR28\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. However, few reports have focused on perioperative PFF and stem subsidence after THA with a comparison different femoral component designs at a single center in a population with matching with characteristics or bone morphology. Therefore, this study aimed to compare the incidence of PFF and stem subsidence between two types of cementless femoral components in patients undergoing THA using propensity score matching.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e This study was approved by our institutional review board. It was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all patients prior to study.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Population\u003c/h2\u003e \u003cp\u003eSeven hundred fifty-three primary cementless THAs using a conventional fit-and fill stem (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea; PerFix910, Kyocera, Kyoto, Japan) and 526 primary cementless THAs using a modern tapered-wedge stem (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb; Initia, Kyocera, Kyoto, Japan) were performed using the posterolateral approach at our institution between January 2013 and June 2020. Five experienced hip surgeons performed the operations, each with \u0026gt;\u0026thinsp;50 THAs/year of experience. At our institution, a conventional fit-and-fill stem is used for the cementless THA. However, since August 2017, we have been using a modern tapered-wedge stems for various types of femoral morphologies in THA. Therefore, the choice of stem type was based on its historical usage.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData Collection\u003c/h3\u003e\n\u003cp\u003eAge, sex, BMI, basic diseases, and history of femoral osteotomy were investigated. Stem sizes, and offset (standard or high) were recorded from surgical records. Radiologically, the Dorr, Crowe, and Bombelli classifications, neck-shaft angle, and femoral bowing (anteroposterior [AP] and lateral views) were evaluated using preoperative radiographs [\u003cspan additionalcitationids=\"CR31 CR32\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePostoperative radiographs were assessed by two observers (S.I. and K.S.), who are orthopedic surgeons with extensive diagnostic imaging experience, using a digital imaging system (Synapse Digital Imaging System; Fujifilm Medical Imaging, Tokyo, Japan); only mean values were used in statistical analysis. Alignment of the inserted femoral component was classified as varus, valgus, or neutral in AP radiographs, and as extension, flexion, or neutral in lateral radiographs. An angle\u0026thinsp;\u0026gt;\u0026thinsp;3\u0026deg; was defined as positive for all parameters [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Subsidence was defined as a femoral stem distalization in reference to the major trochanter, according to a previous report [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The distance between the apex of the major trochanter and the stem shoulder was measured at three different time points (immediately [0 W], 1 week [1 W], and 6 weeks [6 W] postoperatively), and the degree of stem subsidence was assessed by comparing the distance at each time point (0 W versus [vs.] 1 W, 1 W vs. 6 W, and 0 W vs. 6 W) in both stems. Substantial stem subsidence was defined as \u0026ge;\u0026thinsp;2 mm according to previous studies [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. We standardized the rotation of the lower limbs on AP radiographs by positioning both patellae in an exact frontal position throughout the radiological examination. Postoperative PFF was evaluated using both AP radiography and computed tomography (CT), whereas intraoperative PFF was investigated using surgical records.\u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eStatistical analyses were performed using univariate, multivariate, and propensity score matching analyses (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The chi-square or Fisher exact probability test was used to compare sex; basic disease; previous history of femoral osteotomy; Dorr, Crowe, and Bombelli classifications; neck offset (standard/high offset); the presences of PFF and stem subsidence (\u0026ge;\u0026thinsp;2mm); and other postoperative complications including dislocation or deep infection between the fit-and-fill and tapered-wedge stem groups. Age, BMI, neck-shaft angle, femoral bowing, and degree of stem subsidence were compared between the two groups using the unpaired \u003cem\u003et\u003c/em\u003e-test. Multivariate analysis was performed to identify the parameters associated with PFF or stem subsidence using stepwise logistic regression with the variable selection (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.2). Patients who underwent THA using tapered-wedge stem were matched to those who underwent THA using a fit-and-fill stem at a ratio of 1:1 by greedy matching on the logit of propensity scores with a caliper of 0.2x the standard deviation (SD) [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. Age at the time of surgery, sex, BMI, and Dorr type were included as confounders when calculating the propensity score using multivariate logistic regression analysis for each patient. The patients were matched using the nearest-neighbor technique, and propensity score matching was performed between the 478 fit-and-fill stems 478 tapered-wedge stems. All statistical analyses were performed using JMP software (version 9.0.1; SAS Institute Inc., Cary, NC, USA), and statistical significance was set at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003ePatients Demographics\u003c/h2\u003e \u003cp\u003eThe detailed patient characteristics are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The fit-and-fill stem group included 116 males and 637 females with a mean age at surgery of 65.6 years (SD: 10.9). The tapered-wedge stem group included 106 males and 420 females with a mean age of 63.4 years (SD: 12.4). There were significant differences in sex and age between the groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0009 and 0.0274, respectively). The mean BMI values were 24.2 kg/m\u003csup\u003e2\u003c/sup\u003e (SD: 3.9) in the fit-and-fill stem group, and 24.0 kg/m\u003csup\u003e2\u003c/sup\u003e (SD: 4.0) in the tapered-wedge stem group, showing no significant difference between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.4367). The reasons for surgery included 691 hips with OA; 56 with osteonecrosis of the femoral head (ONFH), and six with rheumatoid arthritis (RA) in the fit-and-fill stem group and 428 with OA, 90 with ONFH, and eight with RA in the tapered-wedge stem group. These reasons were significantly different between the groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001). There was also a significant difference in the history of femoral osteotomy between the groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0357). Regarding bone morphology, there were significant differences in AP femoral bowing and the Bombelli classification (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001 and \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0150, respectively).\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\u003eResults of univariate analyses of cohort characteristics and bone morphologies\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFit-and-fill stem group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTapered-wedge stem group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;753)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;526)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCohort characteristics\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65.6\u0026thinsp;\u0026plusmn;\u0026thinsp;10.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e63.4\u0026thinsp;\u0026plusmn;\u0026thinsp;12.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0009*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSex (male: female)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e116: 637\u003c/p\u003e \u003cp\u003e(85%: 15%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e106: 420\u003c/p\u003e \u003cp\u003e(80%: 20%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0274\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.4367\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\u003eDiagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eOA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e691\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e428\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eOther (ONFH or RA)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHistory of femoral osteotomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43 (5.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17 (3.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0357\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBone morphologies\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eNeck-shaft angle (◦)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e133.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.1979\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eAP bowing (◦)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eBombelli classification (A/N/H)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95/485/172\u003c/p\u003e \u003cp\u003e(13%/64%/23%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e92/339/95\u003c/p\u003e \u003cp\u003e(17%/65%/18%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0150\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCrowe classification (1/2/3/4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e678/50/20/5\u003c/p\u003e \u003cp\u003e(90%/6.6%/2.7%/0.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e477/31/15/3\u003c/p\u003e \u003cp\u003e(90.7%/5.8%/2.9%/0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.9452\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eDorr classification (A/B/C)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e244/462/47\u003c/p\u003e \u003cp\u003e(32%/61%/7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e165/318/43\u003c/p\u003e \u003cp\u003e(31%/61%/8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.4131\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eContinuous variables are represented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation. Abbreviations: n, number; BMI, body mass index; OA, osteoarthritis; ONFH, osteonecrosis of the femoral head; RA, rheumatoid arthritis; AP, anteroposterior; A, atrophic; N, normal; H, hypertrophic\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e*\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 indicates significance\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe surgical factors and perioperative complications are shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The rate of stem insertion with extension or flexion in the tapered-wedge stem group (20.5%) was significantly higher than that in the fit-and-fill stem group (13.9%) (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001), owing to the high degree of freedom of stem insertion in the tapered-wedge stem. PFF was observed in 18 patients (2.4%) in the fit-and-fill stem group. Among them, seven had intraoperative PFF and 11 were postoperative PFF. Vancouver type A\u003csub\u003eG\u003c/sub\u003e fracture was present in 15 cases and type B\u003csub\u003e2\u003c/sub\u003e fracture in three cases. Conservative treatment was initiated in 13 patients, and five patients underwent a second surgery (three revision THAs [Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e] and two osteosynthesis). In contrast, PFF was observed in only four patients (0.8%) in the tapered-wedge stem group. All four patients had postoperative Vancouver Type A\u003csub\u003eG\u003c/sub\u003e fractures; thus, they were treated conservatively. There was significant difference in the rate of PFF between the groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0290).\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\u003eResults of univariate analyses of surgical factors and perioperative complications\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFit-and-fill stem group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTapered-wedge stem group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;753)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;526)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSurgical factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eVarus or valgus stem insertion on AP view (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.3173\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;3\u0026deg; of varus or valgus stem insertion on AP view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e29 (3.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20 (3.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.9642\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eFlexion or extension stem insertion on lateral view (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.82\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.16\u0026thinsp;\u0026plusmn;\u0026thinsp;1.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;3\u0026deg; of flexion or extension stem insertion on lateral view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e92 (13.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e108 (20.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSTD/HO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3%/97%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e51%/49%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003ePerioperative complications\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eDislocation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9 (1.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4 (0.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.5759\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eInfection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2 (0.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.1689\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePFF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18 (2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4 (0.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0290\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eIntraoperative/postoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7/11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eVancouver classification\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eType A\u003csub\u003eG\u003c/sub\u003e: 15, Type B\u003csub\u003e2\u003c/sub\u003e: 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eType A\u003csub\u003eG\u003c/sub\u003e: 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eTreatment (surgical/conservative)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5/13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eMethods of surgical treatment\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eStem revision: 3, Plating: 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eStem subsidence (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\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\u003eDuration from\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 W to 6 W\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.50\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0177\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;2-mm subsidence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e79 (10.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10 (1.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\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\u003e1 W to 6 W\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.25\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.1295\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;2-mm subsidence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54 (7.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8 (1.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eAbbreviations: STD, standard; HO, high-offset; PFF; periprosthetic femoral fracture, 0W, immediate after surgery; 1W, 1 week after the surgery; 6W, 6 weeks after surgery\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe mean degree of stem subsidence from 0\u0026ndash;6 W was significantly higher in the fit-and-fill stem group than in the tapered-wedge stem group. The rates of \u0026ge;\u0026thinsp;2-mm stem subsidence from 0\u0026ndash;6 W and 1\u0026ndash;6 W were significantly higher in the fit-and-fill stem group (10.5% and 7.2%, respectively) than in the tapered-wedge stem group (1.9% and 1.5%, respectively) (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001 for both).\u003c/p\u003e \u003cp\u003eRegarding other early postoperative complications, dislocation was observed in nine patients (1.2%) of the fit-and-fill stem group, whereas that was observed in four patients (0.7%) of the tapered-wedge stem group. Deep infection was observed only in two patients (0.4%) of the tapered-wedge stem group. There were no significant differences in the rates of dislocation or deep infection between the groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.5759 and \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.1689, respectively).\u003c/p\u003e \u003cp\u003eMultivariate analysis demonstrated that older age, previous history of osteotomy, and fit-and-fill stem were independently associated with PFF (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, P\u0026thinsp;=\u0026thinsp;0.00808, 0.00222, and 0.03699, respectively) and that older age and fit-and-fill stem were independently associated with \u0026ge;\u0026thinsp;2-mm subsidence after THA (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, P\u0026thinsp;=\u0026thinsp;0.03870 and \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001, respectively)\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\u003eIndependent factors associated with PFF and \u0026ge;\u0026thinsp;2-mm stem subsidence after THA in multivariate analyses\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParameter\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOdds Ratio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePFF\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\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOlder age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.01\u0026ndash;1.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00808\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrevious history of femoral osteotomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.42\u0026ndash;22.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00222\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFit-and-fill stem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.00\u0026ndash;8.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.03699\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStem valgus insertion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.81\u0026ndash;6.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13157\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStem flexion insertion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.85\u0026ndash;6.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.09617\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;2-mm stem subsidence\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\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOlder age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.00\u0026ndash;1.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.03870\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\u003e1.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.86 \u0026minus;\u0026thinsp;2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13721\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBombelli classification (atrophic)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83\u0026ndash;2.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.19101\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFit-and-fill stem\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.22\u0026ndash;12.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStem extension insertion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.32\u0026ndash;1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.08389\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eAbbreviations: CI, Confidence interval\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eOutcomes after Matching\u003c/h2\u003e \u003cp\u003eA total of 478 patients (\u0026gt;\u0026thinsp;90%) who underwent THA using a tapered-wedged stem were matched to patients who underwent THA using a fit-and-fill stem, with standardized differences of \u0026lt;\u0026thinsp;10% for four covariates (age, sex, BMI, and Dorr type), indicating an adequate match (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). After matching, the rates of perioperative PFF and \u0026ge;\u0026thinsp;2-mm stem subsidence in the fit-and-fill stem and tapered-wedge stem groups were 2.3% and 0.6%, and 7.2% and 1.5%, respectively. The rate of PFF was significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0264; 95% confidence interval [CI]: 1.0\u0026ndash;13.5, odds ratio [OR]: 3.7), and the same results was observed for \u0026ge;\u0026thinsp;2-mm stem subsidence (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001; 95% CI: 2.2\u0026ndash;11.7, OR: 5.2).\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 PFF and \u0026ge;\u0026thinsp;2-mm stem subsidence after THA between the fit-and-fill and tapered-wedge stem groups using propensity score matching.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFit-and-fill stem\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;478)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTapered wedge stem\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;478)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOdd Ratio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65.1\u0026thinsp;\u0026plusmn;\u0026thinsp;11.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e64.9\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.7800\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male: female)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e84%/16%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85%/15%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.4791\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (Kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.5927\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDorr classification (A/B/C)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32%/60%/8%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32%/61%/7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003en/a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.9179\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePFF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (2.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.0\u0026ndash;13.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0264\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;2-mm stem subsidence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0 W to 6 W\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e56 (11.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9 (1.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.4\u0026ndash;14.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 W to 6 W\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34 (7.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (1.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.2\u0026ndash;11.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eAbbreviation: n/a, not applicable\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003ePrevious studies reported that age, sex, BMI, and bone morphology, e.g., Dorr type, are essential parameters for PFF and stem subsidence [\u003cspan additionalcitationids=\"CR22 CR23 CR24 CR25 CR26 CR27 CR28\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. A PFF is well recognized as a severe complication of THA. The functional outcome (Oxford 12 hip score) of 232 patients who underwent revision THA for the treatment of PFF was significantly worse than that of 232 patients who underwent revision THA for the treatment of aseptic loosening [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Additionally, a higher mortality rate (7.3%) 6 months after revision THA in patients with PFF than in those with aseptic loosening (0.9%) [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Age is frequently cited as a risk factor of PFF. Franklin et al. reviewed 16 fractures out of 454 cementless THA and found a significant association between an elevated risk of fracture and patient age [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. A single-center investigation of \u0026gt;\u0026thinsp;6000 cases of primary cementless THA reported that female sex, BMI\u0026thinsp;\u0026lt;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e, and age\u0026thinsp;\u0026gt;\u0026thinsp;65 years were independent risk factors for PFF [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Similarly, in our study, the fit-and-fill stem group, which had a significantly higher incidence of perioperative periprosthetic fractures, included a higher proportion of older and female patients than the tapered wedge stem group.\u003c/p\u003e \u003cp\u003eA previous history of femoral osteotomy has also been reported as a risk factor for PFF. Ohishi et al. investigated the incidence of PFF during total hip arthroplasty (THA) in patients with a history of femoral osteotomy, reporting a higher rate of 4 out of 66 cases (6.1%) compared to THA without a history of osteotomy [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. The reasons for the higher incidence of periprosthetic femoral fractures in cases following femoral osteotomy include severe proximal femoral deformity and sclerotic calcar. In our current study, multivariate analysis also identified a history of femoral osteotomy as a significant risk factor for periprosthetic femoral fractures. To evaluate differences in the risk of PFF between stem types, cases with a history of femoral osteotomy were excluded in the propensity score matching.\u003c/p\u003e \u003cp\u003eSubsidence is a known complication of THA. Walker et al. reported that subsidence of the femoral stem can predict clinical outcomes and that decreased subsidence leads to better results [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In addition, considerable subsidence may contribute to postoperative instability and leg length discrepancy [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Radiographic analysis revealed substantial stem subsidence in 52 of 180 patients (28.9%). In the multivariate analysis, older age was an independent risk factor for early stem subsidence [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Johanson et al. revealed that male sex was an independent risk factor for stem subsidence [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e], and Reinbacher et al. reported a higher risk for subsidence in male and overweight patients after THA using a short femoral cementless stem [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Several studies have reported that overweight or obesity is a significant risk factor for stem subsidence. Physical patient characteristics, e.g., body weight\u0026thinsp;\u0026gt;\u0026thinsp;75kg, substantially influenced stem subsidence after cementless THA [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. A large study of 502 hips treated with primary THA using a cementless stem found that the average subsidence of the stem at the final follow-up was 2.2 mm [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Of these, 17.3% had considerable subsidence (\u0026gt;\u0026thinsp;5 mm). Most cases of stem subsidence occur within 3\u0026ndash;6 months after surgery, and femoral stem subsidence was associated with BMI (\u0026gt;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e) [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Song et al. investigated the subsidence of a collarless hydroxyapatite (HA)-coated stem [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Their study demonstrated that Dorr type C femoral bone had a higher risk of subsidence when uncemented collarless HA-coated stems were used [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Therefore, this study compared the rate of PFF and stem subsidence between the fit-and-fill stem and tapered-wedge stem groups after matching for age, sex, BMI, and Dorr type to assess the influence of stem design.\u003c/p\u003e \u003cp\u003eThere have been few reports on PFF and stem subsidence comparing different types of stems at a single center. Sershon et al. compared the PFF of cementless fit-and-fill stems (metaphyseal filling) with that of cementless single-wedge tapered-wedge stems [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. They reported that the PFF rate was 1.41% and that single-wedge tapered stem types were more prone to PFF than fit-and-fill designs [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Grant et al. compared the subsidence of a cementless fit-and-fill stem to that of a cementless tapered-wedge stem [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. The mean degree of subsidence 4 weeks after THA was significantly lower in 65 patients treated with a tapered-wedge stem (0.3 mm) than in 61 patients treated with a fit-and-fill stem (1.1 mm), which was consistent with our results (taper wedge, 0.24 mm; fit-and-fill, 0.50 mm). However, these studies compared the rate of PFF or stem subsidence between two types of cementless stems without matching for age, sex, BMI, and bone morphology, e.g., Dorr type. Therefore, the purpose of our study was to unify these factors and examine the effects of stem design on the rate of PFF and stem subsidence. Here, the rates of PFF and \u0026ge;\u0026thinsp;2-mm of stem subsidence were significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group. Thus, this is the first report on severe perioperative complications, such as PFF and stem subsidence, in THA using cementless stems that matched patient background characteristics including age, sex, BMI, and Dorr type with respect to the stem type.\u003c/p\u003e \u003cp\u003eRegarding the lower rate of PFF and stem subsidence in the tapered-wedge stem group than in the fit-and-fill stem group observed in our study, a recent comparative study mentioned that tapered-wedge stems are designed to achieve a more congruent cortical fit in the coronal plane and have demonstrated excellent long-term results over 25 years, with a low loosening rate (1.4%) [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. We consider that the mediolateral cortical bone quality at the level of initial fixation in the tapered-wedge stem (bellow the lesser trochanter) is better than that in the fit-and-fill stem (above the lesser trochanter) in most femurs, which may be related to the differences in the degree of PFF and stem subsidence between the study groups. Additionally, the fit-and-fill stem required reaming and broaching, whereas the tapered-wedge stem required only broaching. This difference in surgical steps might also affect the frequency of PFF occurrence.\u003c/p\u003e \u003cp\u003eThere were several limitations to the current study. First, this study was not prospective and randomized. Therefore, the precise effect of the type of stem on PFF or subsidence after THA should be further confirmed in a randomized controlled study. Second, this study evaluated stem subsidence only early (up to 6 W) after surgery in both fit-and-fill and tapered-wedge stems, although Dalury et al. reported that subsidence was apparent at 6 weeks and remained stable at an average of 6 years of follow-up [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. Finally, the implants used in this study are not commonly used globally.\u003c/p\u003e \u003cp\u003eIn conclusion, a tapered-wedge stem is more suitable than a fit-and-fill stem for any age, sex, and type of physique or femoral morphology to avoid early perioperative complications, such as PFF and stem subsidence, in cementless THA.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eTHA, total hip arthroplasty; OA, osteoarthritis; PFF, periprosthetic femoral fracture; ONFH, osteonecrosis of the femoral head; BMI, body mass index; AP, anteroposterior; CT, computed tomography; vs., versus; SD, standard deviation; CI, confidence interval; OR, odds ratio; RA, rheumatoid arthritis; HA, hydroxyapatite\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSI performed the literature review and drafted the manuscript. YN supervised writing of the manuscript. SI, KS, GM, SH, MF, SK, TS, RY, DH, and TU contributed to the data collection. SI and KS analyzed the data. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported in part by a Grant-in-Aid in Scientific Research (No. JP19K09628) from the Japan Society for the Promotion of Science.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective study was approved by Kyushu University institutional review board for clinical research (NO. 30-91). Written informed consent was obtained from all patients prior to study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNowak, M., Kusz, D., Wojciechowski, P. \u0026amp; Wilk, R. Risk factors for intraoperative periprosthetic femoral fractures during the total hip arthroplasty. \u003cem\u003ePol. Orthop. Traumatol.\u003c/em\u003e \u003cb\u003e77\u003c/b\u003e, 59\u0026ndash;64 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHagel, A., Siekmann, H. \u0026amp; Delank, K. S. Periprosthetic femoral fracture- an interdisciplinary challenge. \u003cem\u003eDtsch. Arztebl Int.\u003c/em\u003e \u003cb\u003e111\u003c/b\u003e, 658\u0026ndash;664 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKoenig, K., Huddleston, J. I. 3rd, Huddleston, H., Maloney, W. J. \u0026amp; Goodman, S. B. Advanced age and comorbidity increase the risk for adverse events after revision total hip arthroplasty. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e27\u003c/b\u003e, 1402\u0026ndash;1407 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDumont, G. D., Zide, J. R. \u0026amp; Huo, M. H. Periprosthetic Femur Fractures: Current Concepts and Management. \u003cem\u003eYSART\u003c/em\u003e \u003cb\u003e21\u003c/b\u003e, 9\u0026ndash;13 (2010).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMasri, B. A., Meek, R. M. D. \u0026amp; Duncan, C. P. Periprosthetic fractures evaluation and treatment. \u003cem\u003eClin. Orthop. Relat. Res.\u003c/em\u003e \u003cb\u003e420\u003c/b\u003e, 80\u0026ndash;95 (2004).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchwarzkopf, R., Oni, J. K. \u0026amp; Marwin, S. E. Total hip arthroplasty periprosthetic femoral fractures: a review of classifica tion and current treatment. \u003cem\u003eBull. Hosp. Jt. Dis.\u003c/em\u003e \u003cb\u003e71\u003c/b\u003e, 68\u0026ndash;78 (2013).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYoung, S. W., Walker, C. G. \u0026amp; Pitto, R. P. Functional outcome of femoral peri prosthetic fracture and revision hip arthroplasty: a matched-pair study from the New Zealand Registry. \u003cem\u003eActa Orthop.\u003c/em\u003e \u003cb\u003e79\u003c/b\u003e, 483\u0026ndash;488 (2008).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eK\u0026auml;rrholm, J., Borss\u0026eacute;n, B., L\u0026ouml;wenhielm, G. \u0026amp; Snorrason, F. Does early micromotion of femoral stem prostheses matter? 4\u0026ndash;7-year stereoradiographic follow-up of 84 cemented prostheses. \u003cem\u003eJ. Bone Joint Surg. Br.\u003c/em\u003e \u003cb\u003e76\u003c/b\u003e, 912\u0026ndash;917 (1994).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCampbell, D. et al. Early migration characteristics of a hydroxyapatite-coated femoral stem: an RSA study. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e35\u003c/b\u003e, 483\u0026ndash;488 (2011).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGwam, C. U. et al. Current epidemiology of revision total hip arthroplasty in the United States: National Inpatient Sample 2009 to 2013. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e32\u003c/b\u003e, 2088\u0026ndash;2092 (2017).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAl-Najjim, M., Khattak, U., Sim, J. \u0026amp; Chambers, I. Differences in subsidence rate between alternative designs of a commonly used uncemented femoral stem. \u003cem\u003eJ. Orthop.\u003c/em\u003e \u003cb\u003e13\u003c/b\u003e, 322\u0026ndash;326 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStr\u0026ouml;m, H., Nilsson, O., Milbrink, J., Mallmin, H. \u0026amp; Larsson, S. Early migration pattern of the uncemented CLS stem in total hip arthroplasties. \u003cem\u003eClin. Orthop. Relat. Res.\u003c/em\u003e \u003cb\u003e454\u003c/b\u003e, 127\u0026ndash;132 (2007).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSelvaratnam, V., Shetty, V. \u0026amp; Sahni, V. Subsidence in collarless Corail hip replacement. \u003cem\u003eOpen. Orthop. J.\u003c/em\u003e \u003cb\u003e29\u003c/b\u003e, 194\u0026ndash;197 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSudhahar, T. A., Morapudi, S. \u0026amp; Branes, K. Evaluation of subsidence between collarless and collared Corail femoral cement less total hip replacement. \u003cem\u003eJ. Orthop.\u003c/em\u003e \u003cb\u003e6\u003c/b\u003e, e3 (2009).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRies, C., Boese, C. K., Dietrich, F., Miehlke, W. \u0026amp; Heisel, C. Femoral stem subsidence in cementless total hip arthroplasty: a retrospective single-centre study. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e43\u003c/b\u003e, 307\u0026ndash;314 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWalker, P. S., Mai, S. F., Cobb, A. G., Bentley, G. \u0026amp; Hua, J. Prediction of clinical outcome of THR from migration measurements on standard radiographs. A study of cemented Charnley and Stanmore femoral stems. \u003cem\u003eJ. Bone Joint Surg. Br.\u003c/em\u003e \u003cb\u003e77\u003c/b\u003e, 705\u0026ndash;714 (1995).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarrholm, J., Borssen, B., Lowenhielm, G. \u0026amp; Snorrason, F. Does early micromotion of femoral stem prostheses matter? 4-7-year stereoradiographic follow-up of 84 cemented prostheses. \u003cem\u003eJ. Bone Joint Surg. Br.\u003c/em\u003e \u003cb\u003e76\u003c/b\u003e, 912\u0026ndash;917 (1994).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKobayashi, A., Donnelly, W. J., Scott, G. \u0026amp; Freeman, M. A. Early radiological observations may predict the long-term survival of femoral hip prostheses. \u003cem\u003eJ. Bone Joint Surg. Br.\u003c/em\u003e \u003cb\u003e79\u003c/b\u003e, 583\u0026ndash;589 (1997).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKroell, A. et al. Aseptic stem loosening in primary THA: migration analysis of cemented and cementless fixation. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e33\u003c/b\u003e, 1501\u0026ndash;1505 (2009).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStreit, M. R. et al. Early migration predicts aseptic loosening of cementless femoral stems: a long-term study. \u003cem\u003eClin. Orthop. Relat. Res.\u003c/em\u003e \u003cb\u003e474\u003c/b\u003e, 1697\u0026ndash;1706 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGrant, T. W. et al. Cementless Tapered Wedge Femoral Stems Decrease Subsidence in Obese Patients Compared to Traditional Fit-and-Fill Stems. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e32\u003c/b\u003e, 891\u0026ndash;897 (2017).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSershon, R. A., McDonald, J. F. 3rd, Ho, H. \u0026amp; Hamilton, W. G. Periprosthetic Femur Fracture Risk: Influenced by Stem Choice, Not Surgical Approach. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e36\u003c/b\u003e, S363\u0026ndash;S366 (2021).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBerend, K. R. \u0026amp; Lombardi, A. V. Jr Intraoperative femur fracture is associated with stem and instrument design in primary total hip arthroplasty. \u003cem\u003eClin. Orthop. Relat. Res.\u003c/em\u003e \u003cb\u003e468\u003c/b\u003e, 2377\u0026ndash;2381 (2010).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFranklin, J. \u0026amp; Malchau, H. Risk factors for periprosthetic femoral fracture. \u003cem\u003eInjury\u003c/em\u003e \u003cb\u003e38\u003c/b\u003e, 655\u0026ndash;660 (2007).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGromov, K. et al. Risk factors for post-operative periprosthetic fractures following primary total hip arthroplasty with a proximally coated double-tapered cementless femoral component. \u003cem\u003eBone Joint J.\u003c/em\u003e \u003cb\u003e99-B\u003c/b\u003e, 451\u0026ndash;457 (2017).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBornes, T. D. et al. Subsidence of a Single-Taper Femoral Stem in Primary Total Hip Arthroplasty: Characterization, Associated Factors, and Sequelae. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e38\u003c/b\u003e, S174\u0026ndash;S178 (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeiss, F. et al. Differences in femoral component subsidence rate after THA using an uncemented collarless femoral stem: full weight\u0026ndash;bearing with an enhanced recovery rehabilitation versus partial weight\u0026ndash;bearing. \u003cem\u003eArch. Orthop. Trauma. Surg.\u003c/em\u003e \u003cb\u003e142\u003c/b\u003e, 673\u0026ndash;680 (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSong, J. H. et al. Subsidence and perioperative periprosthetic fractures using collarless hydroxyapatite-coated stem for displaced femoral neck fractures according to Dorr type. \u003cem\u003eJ. Orthop. Surg. (Hong Kong)\u003c/em\u003e. \u003cb\u003e27\u003c/b\u003e, 2309499019877530 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReinbacher, P. et al. Three-year migration analysis of a new metaphyseal anchoring short femoral stem in THA using EBRA-FCA. \u003cem\u003eSci. Rep.\u003c/em\u003e \u003cb\u003e12\u003c/b\u003e, 17173 (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDorr, L. D. et al. Structural and cellular assessment of bone quality of proximal femur. \u003cem\u003eBone\u003c/em\u003e \u003cb\u003e14\u003c/b\u003e, 231\u0026ndash;242 (1993).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eClav\u0026eacute;, A. et al. Influence of experience on intra- and inter-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classifications. \u003cem\u003eOrthop. Traumatol. Surg. Res.\u003c/em\u003e \u003cb\u003e102\u003c/b\u003e, 155\u0026ndash;159 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOkano, K., Aoyagi, K., Chiba, K., Motokawa, S. \u0026amp; Matsumoto, T. Bone mineral density is not related to osteophyte formation in osteoarthritis of the hip. \u003cem\u003eJ. Rheumatol.\u003c/em\u003e \u003cb\u003e38\u003c/b\u003e, 358\u0026ndash;361 (2011).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkiyama, K. \u0026amp; Shibuya, T. Influence of femoral bowing on range of motion after total hip arthroplasty. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e42\u003c/b\u003e, 1795\u0026ndash;1802 (2018).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEngh, C. A., Bobyn, J. D. \u0026amp; Glassman, A. H. Porous-coated hip replacement. The factors governing bone ingrowth, stress shielding, and clinical results. \u003cem\u003eJ. Bone Joint Surg. Br.\u003c/em\u003e \u003cb\u003e69\u003c/b\u003e, 45\u0026ndash;55 (1987).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTyrpenou, E. et al. A Large-Scale Fifteen-Year Minimum Survivorship of a Cementless Triple Tapered Femoral Stem. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e35\u003c/b\u003e, 2161\u0026ndash;2166 (2020).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBangalore, S. et al. Everolimus-eluting stents or bypass surgery for multivessel coronary disease. \u003cem\u003eN Engl. J. Med.\u003c/em\u003e \u003cb\u003e372\u003c/b\u003e, 1213\u0026ndash;1222 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOhishi, M. et al. Cementless total hip arthroplasty for patients previously treated with femoral osteotomy for hip dysplasia: the incidence of periprosthetic fracture. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e40\u003c/b\u003e, 1601\u0026ndash;1606 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLo, I. N. et al. Initial femoral stem position in cementless bipolar hemiarthroplasty for femoral neck fracture in elderly patients is associated with early implant subsidence: A radiographic analysis. \u003cem\u003eInjury\u003c/em\u003e \u003cb\u003e52\u003c/b\u003e, 1801\u0026ndash;1806 (2021).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJohanson, P. E., Antonsson, M., Shareghi, B. \u0026amp; K\u0026auml;rrholm, J. Early Subsidence Predicts Failure of a Cemented Femoral Stem With Minor Design Changes. \u003cem\u003eClin. Orthop. Relat. Res.\u003c/em\u003e \u003cb\u003e474\u003c/b\u003e, 2221\u0026ndash;2229 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStihsen, C., Radl, R., Keshmiri, A., Rehak, P. \u0026amp; Windhager, R. Subsidence of a cementless femoral component influenced by body weight and body mass index. \u003cem\u003eInt. Orthop.\u003c/em\u003e \u003cb\u003e36\u003c/b\u003e, 941\u0026ndash;947 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMcCalden, R. W., Korczak, A., Somerville, L., Yuan, X. \u0026amp; Naudie, D. D. A randomised trial comparing a short and a standard-length metaphyseal engaging cementless femoral stem using radiostereometric analysis. \u003cem\u003eBone Joint J.\u003c/em\u003e \u003cb\u003e97\u003c/b\u003e, 595\u0026ndash;600 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDalury, D. F., Kelley, T. C. \u0026amp; Adams, M. J. Modern proximally tapered uncemented stems can be safely used in Dorr type C femoral bone. \u003cem\u003eJ. Arthroplasty\u003c/em\u003e. \u003cb\u003e27\u003c/b\u003e, 1014\u0026ndash;1018 (2012).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Total hip arthroplasty, Periprosthetic femoral fracture, Stem subsidence, Fit-and-fill stem, Tapered-wedge stem, Propensity score matching analysis","lastPublishedDoi":"10.21203/rs.3.rs-5822802/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5822802/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Few reports have focused on major perioperative complications, including periprosthetic femoral fracture (PFF) and stem subsidence in cementless total hip arthroplasty (THA), after standardizing the patient’s background and comparing different femoral component design at a single center. Therefore, this study aimed to compare the incidence of PFF and stem subsidence in patients undergoing THA between two types of cementless femoral component.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Between January 2013 and June 2020, 753 primary cementless THAs using a fit-and-fill stem and 526 using a tapered-wedge stem were performed at our institution. The patient’s background characteristics, radiographic findings, and perioperative complications were compared using univariate, multivariate, and propensity score analyses, matching sex, age, body mass index, and femoral morphology (Dorr type) between the two groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e In the univariate analyses, the rates of perioperative PFF and ≥ 2-mm stem subsidence were significantly higher in the fit-and-fill stem group than in the tapered-wedge group (\u003cem\u003eP\u003c/em\u003e = 0.290 and \u003cem\u003eP\u003c/em\u003e = 0.0001, respectively). The mean age and proportion of female in the fit-and-fill stemgroup were also significantly higher than those in the tapered-wedge group (\u003cem\u003eP\u003c/em\u003e = 0.0274 and 0.0009, respectively). Four hundred and seventy-eight THAs were extracted from both groups on the basis of propensity score matching. After matching, the rates of perioperative PFF and ≥2-mm stem subsidence in the fit-and-fill stem and tapered-wedge stem groups were 2.3% and 0.6%, and 7.2% and 1.5%, respectively. The rate of PFF was significantly lower in the tapered-wedge stem group than in the fit-and-fill stem group (\u003cem\u003eP\u003c/em\u003e = 0.0264; 95% confidence interval [CI]: 1.0–13.5, odds ratio [OR]: 3.7), and the same results was observed for ≥2-mm stem subsidence (\u003cem\u003eP\u003c/em\u003e = 0.0001; 95% CI: 2.2–11.7, OR: 5.2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e Tapered-wedge stem is more suitable for any age, gender, and type of physique or femoral morphology than the fit-and-fill stem to avoid early perioperative complications, such as a PFF and stem subsidence in cementless THA.\u003c/p\u003e","manuscriptTitle":"Comparison of early periprosthetic femoral complications following cementless total hip arthroplasty between fit-and-fill stems and tapered-wedge stems: a propensity score matching study from a single center","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-22 05:28:06","doi":"10.21203/rs.3.rs-5822802/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-09T17:23:49+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-02T12:54:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"330220641565282786745515589674490203744","date":"2025-10-02T12:06:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"333488086145874619321163287573992958577","date":"2025-09-04T13:28:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-01T21:23:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-17T17:04:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"229910404434521027093347096798973422296","date":"2025-07-09T12:32:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"229053824682439484077345930122974650916","date":"2025-07-09T11:55:43+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-05-08T12:11:15+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-06T09:59:42+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-01-17T15:15:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-01-16T11:42:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-01-13T22:17:11+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9f0713ca-574d-4333-813c-121b65c531ca","owner":[],"postedDate":"January 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":43033958,"name":"Health sciences/Medical research"},{"id":43033959,"name":"Health sciences/Risk factors"}],"tags":[],"updatedAt":"2025-10-30T15:38:23+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-22 05:28:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5822802","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5822802","identity":"rs-5822802","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}