Percutaneous Kyphoplasty Warning Line for Preventing Bone Cement Leakage

Percutaneous Kyphoplasty Warning Line for Preventing Bone Cement Leakage | 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 Research Article Percutaneous Kyphoplasty Warning Line for Preventing Bone Cement Leakage Dongyue Li, Luming Tao, Qingjun Su, Xinuo Zhang, Peng Yin This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6157948/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract ‌ Background ‌ With the global aging population, osteoporotic fractures—particularly osteoporotic vertebral compression fractures (OVCFs)—have emerged as a critical health concern, severely impacting the quality of life in elderly individuals. Percutaneous kyphoplasty (PKP) has demonstrated significant clinical efficacy in treating OVCFs by stabilizing fractures and alleviating pain‌. However, bone cement leakage during PKP remains a major complication, posing risks of spinal cord compression. This study aimed to establish a radiographic "warning line" to predict and mitigate posterior vertebral wall cement leakage during PKP. ‌ Methods‌ From February 2018 to September 2022, 88 patients (106 vertebral bodies) with OVCFs treated by unilateral PKP at a single center were retrospectively analyzed. Inclusion criteria required intraoperative X-ray confirmation of bone cement diffusion reaching the posterior vertebral margin. Postoperative three-dimensional CT scans classified vertebrae into Group A (no leakage, n=44) and Group B (leakage, n=62). Parameters including age, bone mineral density (T-score), balloon pressure, contrast volume, and cement volume were compared. The posterior vertebral wall was divided into upper, middle, and lower thirds to assess leakage distribution. Lateral X-ray measurements defined the warning line (line b) as the apex of cement diffusion parallel to the posterior vertebral margin (line a), with the ratio ab/ac calculated to quantify its position relative to the sagittal diameter. ‌ Results‌ All patients exhibited significant pain relief (preoperative VAS: 5.69±1.15 vs. postoperative: 1.20±0.79, P <0.05) without neurological complications. Posterior vertebral wall leakage occurred in 58.5% (62/106) of cases, predominantly in the middle (61.1%) and lower thirds (66.7%) (P0.05). The warning line ratio (ab/ac) in Group A was 6.8±2.17%, indicating that maintaining cement diffusion anterior to this threshold correlated with reduced leakage risk. ‌ Conclusions‌ PKP is a safe and effective intervention for OVCFs, but posterior vertebral wall leakage remains prevalent. Cement dispersion exceeding 6.8% of the sagittal diameter from the posterior margin significantly increases leakage risk, particularly in the middle and lower thirds of the vertebral wall‌. The proposed warning line provides a practical intraoperative radiographic marker to enhance procedural safety and reduce complications. Percutaneous kyphoplasty (PKP) Osteoporotic vertebral compression fractures (OVCFs) Bone cement leakage Radiographic warning line Figures Figure 1 Figure 2 Introduction With the escalating global aging population, osteoporotic fractures—particularly osteoporotic vertebral compression fractures (OVCFs)—have evolved into a critical public health challenge, severely compromising mobility and independence in older adults‌. OVCFs account for over 40% of osteoporosis-related complications, with an annual incidence exceeding 1.4 million cases worldwide ‌[1]. Percutaneous kyphoplasty (PKP) has been established as a minimally invasive intervention for OVCFs, demonstrating superior outcomes in pain relief and vertebral height restoration compared to conservative treatments‌ [2,3]. However, bone cement leakage persists as the most prevalent complication, occurring in 28.9–39.3% of PKP procedures‌ [4]. While often asymptomatic, cement leakage may precipitate catastrophic sequelae, including spinal cord compression from intravertebral canal extravasation or life-threatening pulmonary embolism secondary to intravascular migration [4–6]. Current evidence identifies both vertebral and procedural factors influencing leakage risks[ 3 , 7 , 8 ]. Vertebral morphology (e.g., cortical defects, fracture patterns), cement viscosity, and injection volume collectively contribute to leakage susceptibility ‌[ 7 , 8 ]. Intraoperative fluoroscopic monitoring is critical for early detection, yet anatomical variations in posterior vertebral wall depressions complicate real-time assessments. Recent guidelines suggest limiting cement dispersion to the posterior one-sixth of the vertebral sagittal diameter on lateral fluoroscopy to mitigate leakage [ 9 ]. Paradoxically, achieving therapeutic cement distribution frequently necessitates exceeding this threshold, raising concerns about unquantified leakage risks. Notably, neurological complications from intravertebral canal leakage remain rare despite radiographic evidence of cement extravasation [ 10 – 12 ]. This study addresses two unresolved questions: First, the ‌actual incidence‌ of posterior vertebral wall cement leakage when intraoperative fluoroscopy shows cement dispersion approaching the posterior vertebral margin; Second, the ‌radiographic warning threshold‌ (quantified as a percentage of sagittal diameter) to guide safe cement injection without compromising therapeutic efficacy. By correlating intraoperative fluoroscopic measurements with postoperative CT findings, we aim to establish evidence-based parameters for optimizing PKP safety while maintaining clinical effectiveness. Materials and Methods Patient selection The study subjects were selected from patients with OVCFs who underwent PKP surgery at our research institute between February 2018 and September 2022. The inclusion criteria for patients were as follows: (1) osteoporotic thoracic or lumbar vertebral compression fractures with a bone density T score ≤ -1.0; (2) no preoperative neurological symptoms; (3) disease duration ≤ 3 weeks; (4) clear history of low back pain with a visual analogue scale (VAS) score ≥ 4; (5) surgery performed by the same surgeon via unilateral puncture PKP; and (6) intraoperative X-ray fluoroscopy lateral images showing bone cement dispersion reaching or approaching the posterior vertebral edge, as measured by two doctors. The exclusion criteria were as follows: (1) surgically confirmed infectious or pathological fractures; (2) congenital vertebral anomalies (e.g., hemivertebrae or congenital fusion vertebrae); (3) presence of preoperative neurological symptoms; (4) nonosteoporotic vertebral fractures; (5) inability to clearly identify the posterior vertebral wall for any reason; and (6) previous vertebral fractures or fractures with a disease duration > 3 weeks. A total of 88 patients (106 vertebral bodies) meeting these criteria were included. Surgical Procedure Patients were positioned prone, and local anaesthesia was administered at the puncture site. Under X-ray fluoroscopy, the puncture needle and cannula were carefully inserted into the vertebral body. The puncture process should avoid areas close to cortical defects, especially those in the posterior vertebral wall. Balloon expansion and high-viscosity cement injection were performed under X-ray fluoroscopy, starting approximately 1 minute and 30 seconds after mixing. The degree of cement dispersion was closely monitored, and the injection was stopped if the cement approached or exceeded the posterior vertebral edge. Finally, the cement delivery device and cannula were removed, and the incision was compressed for hemostasis and covered with a dressing. All procedures were performed by the same surgeon via a unilateral puncture technique. Intraoperative X-ray fluoroscopy was used to ensure symmetrical pedicles in the anteroposterior view and parallel endplates in both the anteroposterior and lateral views. Data collection Clinical baseline data, including age, sex, bone density, surgical segment, balloon pressure, contrast dose, and bone cement volume, were recorded during the perioperative period. The visual analog scale (VAS) score before and after surgery and postoperative neurological complications were recorded. Radiological measurement and indicators All 88 patients received postoperative three-dimensional (3D) CT scans of the thoracic/lumbar spine following PKP. DICOM datasets were reconstructed using advanced volumetric rendering techniques on a dedicated imaging workstation‌. Intraoperative imaging modalities, including real-time X-ray fluoroscopy and CT acquisitions, were systematically archived for multimodal analysis‌. ‌Intraoperative X-ray fluoroscopy images were reviewed to identify cases where bone cement dispersion extended near the posterior vertebral margin‌. ‌Postoperative 3D axial CT images were utilized to measure the spatial distribution and volumetric extent of posterior vertebral wall leakage, applying standardized segmentation protocols‌. ‌Group Classification‌: ‌Group A‌: Absence of cement leakage at the apex of posterior edge dispersion; ‌Group B‌: Confirmed posterior wall leakage, defined as cement extravasation exceeding of the vertebral body volume‌. Patients were stratified into three groups based on sagittal dispersion patterns of bone cement relative to the posterior vertebral wall in intraoperative lateral X-ray fluoroscopy images: ‌Group I‌: Bone cement dispersion edge localized to the upper third of the posterior vertebral wall; ‌Group II‌: Dispersion edge confined to the middle third; ‌Group III‌: Dispersion edge extending to the lower third. A quantitative analysis of posterior vertebral wall leakage was performed using three-dimensional (3D) CT reconstruction to evaluate cement migration patterns‌ In intraoperative lateral X-ray fluoroscopy images ( Fig 1 ): Line ‌a‌ corresponds to the posterior vertebral margin; Line ‌b‌ is drawn parallel to line ‌a‌, passing through the apex of the posterior edge of bone cement dispersion, serving as the warning boundary for posterior cement spread; Line ‌c‌ represents the anterior vertebral margin. The distances ‌ab‌ (between lines a and b) and ‌ac‌ (between lines a and c) are measured to calculate the ratio ‌ab/ac. In reconstructed axial CT images ( Fig 1 ): Line ‌d‌ connects the bilateral cortical apexes of the posterior vertebral margin; Line ‌e‌ is drawn parallel to line ‌d‌ through the apex of the posterior vertebral concavity; Line ‌f‌ parallels line ‌d‌ and aligns with the anterior vertebral margin. The distances ‌de‌ (between lines d and e) and ‌df‌ (between lines d and f) are measured to derive the ratio ‌de/df‌‌. Comparative analysis demonstrates a significant correlation between the ‌ab/ac‌ ratio from X-ray fluoroscopy and the ‌de/df‌ ratio from CT axial imaging, suggesting these parameters may serve as complementary metrics for evaluating posterior bone cement dispersion patterns‌. Statistical analysis Statistical analysis was performed via SPSS 19.0 software. The measurement data were first tested for normality. If the samples conformed to a normal distribution, an independent samples t test or analysis of variance (ANOVA) was used to compare the mean values across groups to determine if there were statistically significant differences. The significance level was set at α=0.05. Results Clinical Outcomes From February 2018 to September 2022, 88 eligible patients (19 males, 69 females) underwent unilateral PKP, involving 106 vertebral levels. No postoperative neurological complications were reported, and all patients completed preoperative and postoperative imaging evaluations. The cohort had a mean age of 73.58 ± 9.59 years (range: 52–89) and an average bone mineral density (BMD) T-score of -3.59 ± 0.86 (range: -2.5 to -5.7). Fracture distribution across vertebral levels included T5 (1 case), T6 (2), T7 (2), T9 (4), T10 (4), T11 (13), T12 (31), L1 (17), L2 (22), L3 (6), and L4 (4). Single-segment fractures accounted for 73 cases, while 15 cases involved two or multiple segments. Preoperative visual analog scale (VAS) scores significantly decreased from 5.69 ± 1.15 to 1.20 ± 0.79 postoperatively ( Table 1 ).‌ Table 1 Clinical data of all patients General Data Total number 88 Male 19 Female 69 Vertebra 106 Mean age 73.58±9.59 Mean BMD -3.59±0.86 Fracture segment T5 1 T6 2 T7 2 T9 4 T10 4 T11 13 T12 31 L1 13 L2 22 L3 6 L4 4 Single-segment fracture 73 Double or multiple segment fractures Preoperative VAS score Postoperative VAS score P (VAS) 15 5.69±1.15 1.20±0.79 0.00* Radiological results Postoperative 3D CT reconstruction identified 44 cases in Group A and 62 cases in Group B with posterior vertebral wall cement leakage, demonstrating an overall incidence rate of 58.5%. Comparative analysis showed no statistically significant intergroup differences in demographic characteristics (sex, age) or procedural parameters including bone density, balloon pressure, contrast agent volume, and bone cement injection volume (all P > 0.05) ( Table 2 ). ‌ Table 2 Comparison between Group A and Group B Age BMD Balloon pressure Contrast agent volume bone cement volume Group A 72.12±9.51 -3.76±0.79 189.03±48.33 2.85±0.62 3.68±1.14 Group B 74.18±9.61 -3.52±0.88 190.00±39.11 2.83±0.52 3.47±1.00 (F value, P ) (0.000, 0.317) Δ (0.105, 0.187) Δ (1.790, 0.914) Δ (0.840, 0.811) Δ (1.295, 0.331) Δ ΔThere was no statistically significant difference, with P >0.05. Based on postoperative 3D CT scans, the posterior vertebral wall was subdivided into three equal segments. A total of 106 vertebral bodies were categorized into three groups according to bone cement distribution patterns within the posterior vertebral wall: Group I (upper third, n=8), Group II (middle third, n=95), and Group III (lower third, n=3). Cement leakage occurred in 25% (2/8) of Group I cases, 61.1% (58/95) of Group II cases, and 66.7% (2/3) of Group III cases, demonstrating statistically significant intergroup differences in leakage rates ( P <0.05). However, no significant differences were observed among groups regarding demographic characteristics (sex, age), bone density, or procedural parameters (balloon pressure, contrast agent volume, cement injection volume) ( P >0.05) ( Table 3 ). Table 3 Comparisons among groups I, II and III Age BMD Balloon pressure Contrast agent volume bone cement volume Group I 76.00±8.90 -3.90±0.93 202.50±58.98 2.56±0.50 3.44±1.40 Group II 73.02±9.57 -3.57±0.86 188.00±40.41 2.85±0.55 3.52±1.02 Group III 85.00±2.65 -3.53±0.91 210.00±30.06 3.00±0.00 4.17±1.04 (F value, P ) (2.623, 0.077) Δ (0.562, 0.572) Δ (0.805, 0.450) Δ (1.185,0.310) Δ (0.590, 0.566) Δ ΔThere was no statistically significant difference, with P >0.05. Warning line in PKP surgery In Group A, comprising 44 vertebral bodies without intraoperative bone cement leakage, radiographic analysis demonstrated a mean ab/ac ratio of (6.8±2.17)% on intraoperative lateral X-ray imaging. Postoperative 3D CT reconstruction revealed a significantly higher de/df ratio of 11.19±3.47% in axial planes ( P <0.05)‌. This statistical discrepancy highlights the critical importance of differentiating intraoperative fluoroscopic measurements from postoperative cross-sectional imaging assessments in vertebral augmentation procedures‌. The study concludes that establishing a safety margin at approximately 6.8% of the vertebral body's sagittal diameter from its posterior wall proves effective for preventing cement extravasation during PKP‌. This spatial parameter, validated through comparative imaging modalities, corresponds to the optimal positioning of cement containment warning markers under real-time fluoroscopic guidance‌. A representative clinical case illustrating this spatial relationship and surgical application is presented in Fig 2 , demonstrating successful cement containment within the proposed safety boundaries‌ Discussion OVCFs are a common type of fragility fracture caused by decreased bone mass. Surgical treatment is a primary approach[ 2 , 3 ], aiming to quickly alleviate back pain, end prolonged bed rest, reduce the incidence of complications such as lower limb venous thrombosis, pneumonia, and pressure sores, and prevent muscle weakness or atrophy due to long-term bed rest, which can further exacerbate bone loss and osteoporosis. Among surgical treatments, PKP is widely applied for osteoporotic vertebral fractures[ 2 , 5 ]. Compared with traditional open surgery, PKP is advantageous because of its shorter duration, less trauma, minimal bleeding, and rapid symptom relief. Cement leakage remains the main complication of PKP, with an incidence rate of 25% reported in the literature[ 13 ]. Leakage into blood vessels or the spinal canal can lead to severe complications, including pulmonary embolism and spinal cord or nerve damage, significantly affecting surgical outcomes and reducing patients' quality of life[ 14 – 16 ]. Therefore, to increase surgical safety, many risk factors for cement leakage have been identified, such as low bone density, hypertension, degree of vertebral compression, presence of vertebral fissures, and cement viscosity[ 17 – 19 ]. However, there is limited research on the early detection and prevention of leakage during surgery. It is challenging to detect early leakage through intraoperative X-ray fluoroscopic lateral views[ 20 ]. Wang et al. [ 8 ] noted that the anatomical feature of the posterior vertebral wall appearing arch shaped and concave inwards on axial CT images makes it difficult to detect cement leakage in a timely and accurate manner through X-ray fluoroscopy during surgery unless CT scans are performed intraoperatively. Yeom et al. [ 20 ] reported that only 7% of intrathecal cement leakage could be detected via lateral views and suggested that cement injection be stopped immediately when it reaches one-fifth of the vertebral body via intraoperative fluoroscopy. However, this indicator is subjectively defined and not an objective measurement. In this study, cases where cement dispersion just reached the posterior edge without leakage were screened via axial postoperative spinal CT images. Measurements of CT axial images and intraoperative fluoroscopic lateral views revealed that the postoperative fluoroscopic measurement results were significantly smaller than the CT measurements were, indicating statistical significance. Zhang et al. [ 9 ] precisely measured the depth of the posterior vertebral concavity via CT. We believe that CT measurements cannot fully represent intraoperative fluoroscopic images because of differences in defining the posterior vertebral edge between the two imaging methods. Intraoperative X-ray fluoroscopic images are more intuitive and immediately useful for reference during surgery. Therefore, on the basis of our study results, we suggest that in intraoperative X-ray fluoroscopic lateral views, the warning line for cement dispersion is approximately 6.8% of the sagittal diameter from the posterior vertebral edge. In actual cases, further observation of postoperative CT and X-ray images revealed that when the posterior vertebral wall was divided into thirds, cement leakage occurred mainly in the middle and lower thirds, with the lowest incidence in the upper third. These findings suggest that the vertebral venous foramen is a high-risk area for posterior vertebral wall cement leakage. Li et al. [ 21 ] reported that the presence of the vertebral venous foramen and relatively sparse trabeculae make the middle region of the vertebral body mechanically weakest. During vertebral compression, the central trabeculae are most severely damaged, with the largest intertrabecular distance, thus resulting in the highest leakage rate [ 22 ]. In some cases, although the degree of cement dispersion exceeded the posterior vertebral edge, further observation of axial postoperative CT images revealed that the cement did not leak into the spinal canal but rather dispersed into the pedicle, possibly explaining the lower incidence of upper third leakage. Therefore, when cement dispersion exceeds the warning line in the middle and lower thirds of the vertebral body, there is a greater risk of posterior wall leakage. Conclusions PKP demonstrates a favorable safety profile in managing OVCFs, though posterior vertebral wall cement leakage remains a notable concern. This study revealed a 58.5% incidence of posterior wall leakage, with most occurrences localized to the middle and lower thirds of the vertebral posterior wall‌. Radiographic analysis established a critical safety boundary at 6.8% of the vertebral sagittal diameter from the posterior margin, serving as an intraoperative fluoroscopic guide for cement dispersion monitoring‌. Clinical observations indicate significantly reduced leakage rates when cement diffusion apex remains anterior to this threshold during PKP procedures. This safety boundary proves effective in mitigating cement extravasation risks and associated complications. Imaging analysis further highlights elevated leakage risks when cement extends beyond the warning line, particularly in the middle and lower vertebral thirds. These findings emphasize the importance of real-time radiographic monitoring and strict adherence to the 6.8% sagittal diameter guideline for optimizing surgical outcomes‌. Abbreviations OVCFs: Osteoporotic vertebral compression fractures; PKP: Percutaneous kyphoplasty; VAS: Visual analog scale; ANOVA: Analysis of variance. Declarations Ethics approval and consent to participate The study involving human participants was conducted in accordance with the ‌Declaration of Helsinki‌ and approved by the ‌ethics committee of Beijing Chaoyang Hospital Affiliated to Capital Medical University. All participants provided written informed consent, and procedures adhered to institutional ethical standards for human subject research‌. Consent for publication Not Applicable. Availability of data and materials All data used and analyzed during this study are available from the corresponding author upon reasonable request. Competing interests The authors declare that they have no competing interests. Funding None. Authors’ contributions Dongyue Li‌: Conceptualized the study design, authored the manuscript, and drafted of the paper‌. Luming Tao‌: Conducted data collection and performed statistical analysis‌. Xinuo Zhang‌: Collaborated in data interpretation and revised the manuscript‌. Qingjun Su‌: Contributed to the study’s methodological framework, oversaw project revisions, and provided supervisory oversight throughout the research process‌. Acknowledgements We would like to thank all the participants in the studies. References Gauthier A, Kanis JA, Jiang Y, et al. Epidemiological burden of postmenopausal osteoporosis in the UK from 2010 to 2021: estimations from a disease model[J]. Arch Osteoporos, 2011,6:179-188. doi:10.1007/s11657-011-0063-y Semaan H, Obri T, Bazerbashi M, et al. Clinical outcome and subsequent sequelae of cement extravasation after percutaneous kyphoplasty and vertebroplasty: a comparative review[J]. Acta Radiol,2018,59(7):861-868. doi:10.1177/0284185117732599 Huang SH, Zhu XW, Xiao D, et al. Therapeutic effect of percutaneous kyphoplasty combined with anti-osteoporosis drug on postmenopausal women with osteoporotic vertebral compression fracture and analysis of postoperative bone cement leakage risk factors: a retrospective cohort study[J]. J Orthop Surg Res, 2019,14(1):452. doi:10.1186/s13018-019-1499-9 LD Rose, G Bateman, A Ahmed. Clinical significance of cement leakage in kyphoplasty and vertebroplasty: a systematic review[J]. Eur Spine J, 2024,33(4):1484-1489. doi: 10.1007/s00586-023-08026-3. Fadili Hassani S, Cormier E, Shotar E, et al. Intracardiac cement embolism during percutaneous vertebroplasty: incidence, risk factors and clinical management[J]. Eur Radiol,2019,29(2):663-73. doi:10.1007/s00330-018-5647-0 Shridhar P, Chen Y, Khalil R, et al. A Review of PMMA Bone Cement and Intra-Cardiac Embolism[J]. Materials(Basel), 2016,9(10):821. doi:10.3390/ma9100821 Ren H, Feng T, Cao J, et al. A Retrospective Study to Evaluate the Effect of Dynamic Fracture Mobility on Cement Leakage in Percutaneous Vertebroplasty and Percutaneous Kyphoplasty in 286 Patients with Osteoporotic Vertebral Compression Fractures[J]. Med Sci Monit, 2022,28:e935080. doi:10.12659/MSM.935080 Wang C, Fan S, Liu J, et al. Basivertebral foramen could be connected with intravertebral cleft: a potential risk factor of cement leakage in percutaneous kyphoplasty[J]. Spine J, 2014,14(8):1551-1558. doi:10.1016/j.spinee.2013.09.025 Zhang S, Wang GJ, Wang Q, et al. A mysterious risk factor for bone cement leakage into the spinal canal through the Batson vein during percutaneous kyphoplasty: a case control study[J]. BMC Musculoskelet Disord, 2019,20(1):423. doi:10.1186/s12891-019-2807-6 Hsieh MK, Kao FC, Chiu PY, et al. Risk factors of neurological deficit and pulmonary cement embolism after percutaneous vertebroplasty[J]. J Orthop Surg Res, 2019, 14(1):406. doi:10.1186/s13018-019-1459-4 Tang C, Tang X, Zhang W, et al. Percutaneous mesh-container-plasty for osteoporotic thoracolumbar burst fractures: A prospective, nonrandomized comparative study[J]. Acta Orthop Traumatol Turc, 2021,55(1):22-27. doi:10.5152/j.aott.2021.20045 Yin P, Li Z, Zhu S, et al. The treatment of osteoporotic thoraco-lumbar burst fractures by unilateral percutaneous kyphoplasty: A prospective observation study[J]. Eur J Pain, 2020,24(3):659-664. doi:10.1002/ejp.1516 Phillips FM, Todd Wetzel F, Lieberman I, et al. An in vivo comparison of the potential for extravertebral cement leak after vertebroplasty and kyphoplasty[J]. Spine (Phila Pa 1976), 2002,27(19):2173-2178. doi:10.1097/00007632-200210010-00018 Harrington KD. Major neurological complications following percutaneous vertebroplasty with polymethylmethacrylate : a case report[J]. J Bone Joint Surg Am, 2001,83(7):1070-1073. doi:10.2106/00004623-200107000-00014 Yoo KY, Jeong SW, Yoon W, et al. Acute respiratory distress syndrome associated with pulmonary cement embolism following percutaneous vertebroplasty with polymethylmethacrylate[J]. Spine (Phila Pa 1976), 2004,29(14):E294-297. doi:10.1097/01.brs.0000131211.87594.b0 Lee ST, Chen JF. Closed reduction vertebroplasty for the treatment of osteoporotic vertebral compression fractures. Technical note[J]. J Neurosurg, 2004,100(4 Suppl Spine):392-396. doi:10.3171/spi.2004.100.4.0392 Rho YJ, Choe WJ, Chun YI. Risk factors predicting the new symptomatic vertebral compression fractures after percutaneous vertebroplasty or kyphoplasty[J]. Eur Spine J, 2012,21(5):905-911. doi:10.1007/s00586-011-2099-5 Li M, Zhang T, Zhang R, et al. Systematic Retrospective Analysis of Risk Factors and Preventive Measures of Bone Cement Leakage in Percutaneous Kyphoplasty[J]. World Neurosurg, 2023,171:e828-836. doi:10.1016/j.wneu.2022.12.117 Xu DL, Ruan CY, Wang Y, et al. Comparison of the clinical effect of unilateral transverse process extrapedicular and bilateral transpedicular percutaneous kyphoplasty for thoracolumbar osteoporotic vertebral compression fracture[J]. Front Surg, 2024,11: 1395289. doi: 10.3389/fsurg.2024.1395289. eCollection 2024 Yeom JS, Kim WJ, Choy WS, et al. Leakage of cement in percutaneous transpedicular vertebroplasty for painful osteoporotic compression fractures[J]. J Bone Joint Surg Br, 2003,85(1):83-89. doi:10.1302/0301-620x.85b1.13026 Li S, Wang C, Shan Z, et al. Trabecular Microstructure and Damage Affect Cement Leakage From the Basivertebral Foramen During Vertebral Augmentation[J]. Spine (Phila Pa 1976), 2017,42(16):E939-948. doi:10.1097/BRS.0000000000002073 Fang N, Wang TY, Wang AB, et al.A predictive nomogram for intradiscal cement leakage in percutaneous kyphoplasty for osteoporotic vertebral compression fractures combined with intravertebral cleft[J].Front Surg, 2022,9:1005220. doi:10.3389/fsurg.2022.1005220. eCollection 2022. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6157948","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":442056329,"identity":"00c8c71b-c4ad-4ac4-8670-c9daf6370c67","order_by":0,"name":"Dongyue Li","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Dongyue","middleName":"","lastName":"Li","suffix":""},{"id":442056330,"identity":"3ded526c-1e5f-4371-a0a4-42674ec5f008","order_by":1,"name":"Luming Tao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Luming","middleName":"","lastName":"Tao","suffix":""},{"id":442056331,"identity":"c3247e22-db4f-47a4-aad0-40e18c9d8ff0","order_by":2,"name":"Qingjun Su","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Qingjun","middleName":"","lastName":"Su","suffix":""},{"id":442056332,"identity":"089252aa-e2be-4eb4-9191-8f67b6fc5ff6","order_by":3,"name":"Xinuo Zhang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xinuo","middleName":"","lastName":"Zhang","suffix":""},{"id":442056333,"identity":"567057fb-d6a9-4e58-ba53-bcd5ba90bd61","order_by":4,"name":"Peng Yin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA30lEQVRIiWNgGAWjYDACZghlx8/MkPggocKGeC3Jku0Njw0enEkj3jLGDWcOPpN82HaIsFKD47zHHnzcUctscCM5rSKB7QADf3t3An4th/nSDWeeOc4neSMt7UYCzx0GiTNnNxDQwmMmzdt2jJnvRg5Qi8QzBgOJXCK0/G07xthwI/9bQYLBYSK1MLbVME44cyCNISGBCC2Sh3nMDXvbDoACOVki4UAaD0G/8J0/Y/bgZ1sdOCo//vxnI8ff3otfi8IBBjYgdRguwINXOQjIN4C11BFUOApGwSgYBSMYAAAuHVA4Gfw8oQAAAABJRU5ErkJggg==","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Peng","middleName":"","lastName":"Yin","suffix":""}],"badges":[],"createdAt":"2025-03-05 02:08:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6157948/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6157948/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":80806627,"identity":"4db17acb-bac1-4d0d-9c48-4c5a854a6eef","added_by":"auto","created_at":"2025-04-17 09:37:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":609762,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea.\u003c/strong\u003e In the intraoperative lateral X-ray fluoroscopic image, line a corresponds to the posterior vertebral margin. Line b is drawn parallel to line a through the apex of the posterior edge of the bone cement distribution. Line c delineates the anterior vertebral border‌. \u003cstrong\u003eb.\u003c/strong\u003e On reconstructed CT axial images, line d is formed by connecting the bilateral cortical apex points along the posterior vertebral margin. Two additional lines (e and f) are then constructed parallel to line d: line e traverses the apex of the posterior vertebral depression, while line f aligns with the anterior vertebral boundary‌.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6157948/v1/ca6a268592831922a7df33b6.png"},{"id":80806679,"identity":"9ef5083a-f18f-4d97-bcbc-04db604ef795","added_by":"auto","created_at":"2025-04-17 09:37:57","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":848321,"visible":true,"origin":"","legend":"\u003cp\u003eFemale patient, 54 years old, suffered from low back pain and limited spinal movement after the fall injury for 2 days. She underwent unilateral percutaneous kyphoplasty (PKP) at L2 and L3.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ea-b\u003c/strong\u003e: Preoperative lumbar CT demonstrated fracture lines in the L2 and L3 vertebral bodies, while lumbar MRI revealed corresponding high signal intensity at these levels, consistent with acute vertebral compression fractures; \u003cstrong\u003ec-d\u003c/strong\u003e: Intraoperative X-ray images (lateral view) showed that L2 bone cement distribution extended posteriorly to precisely reach the predefined warning line (marked by red line). However, the L3 bone cement exhibited posterior diffusion beyond this critical anatomical boundary‌; \u003cstrong\u003ee-f\u003c/strong\u003e: Postoperative lumbar CT reconstruction confirmed satisfactory cement containment within the L2 vertebral body, with cement reaching but not penetrating the posterior vertebral wall. In contrast, the L3 vertebral body displayed cement leakage into the spinal canal, indicating potential compromise of the epidural space.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6157948/v1/37c352107bb8c8b3252e054b.png"},{"id":102397309,"identity":"c2727cc7-cc9d-40c6-be53-022517631f38","added_by":"auto","created_at":"2026-02-11 10:15:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2477084,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6157948/v1/4bf7fc3d-e6b7-4040-86ec-6f393739b40b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Percutaneous Kyphoplasty Warning Line for Preventing Bone Cement Leakage","fulltext":[{"header":"Introduction","content":"\u003cp\u003eWith the escalating global aging population, osteoporotic fractures\u0026mdash;particularly osteoporotic vertebral compression fractures (OVCFs)\u0026mdash;have evolved into a critical public health challenge, severely compromising mobility and independence in older adults\u0026zwnj;. OVCFs account for over 40% of osteoporosis-related complications, with an annual incidence exceeding 1.4\u0026nbsp;million cases worldwide \u0026zwnj;[1]. Percutaneous kyphoplasty (PKP) has been established as a minimally invasive intervention for OVCFs, demonstrating superior outcomes in pain relief and vertebral height restoration compared to conservative treatments\u0026zwnj; [2,3]. However, bone cement leakage persists as the most prevalent complication, occurring in 28.9\u0026ndash;39.3% of PKP procedures\u0026zwnj; [4]. While often asymptomatic, cement leakage may precipitate catastrophic sequelae, including spinal cord compression from intravertebral canal extravasation or life-threatening pulmonary embolism secondary to intravascular migration [4\u0026ndash;6].\u003c/p\u003e \u003cp\u003eCurrent evidence identifies both vertebral and procedural factors influencing leakage risks[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Vertebral morphology (e.g., cortical defects, fracture patterns), cement viscosity, and injection volume collectively contribute to leakage susceptibility \u0026zwnj;[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Intraoperative fluoroscopic monitoring is critical for early detection, yet anatomical variations in posterior vertebral wall depressions complicate real-time assessments. Recent guidelines suggest limiting cement dispersion to the posterior one-sixth of the vertebral sagittal diameter on lateral fluoroscopy to mitigate leakage [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Paradoxically, achieving therapeutic cement distribution frequently necessitates exceeding this threshold, raising concerns about unquantified leakage risks. Notably, neurological complications from intravertebral canal leakage remain rare despite radiographic evidence of cement extravasation [\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study addresses two unresolved questions: First, the \u0026zwnj;actual incidence\u0026zwnj; of posterior vertebral wall cement leakage when intraoperative fluoroscopy shows cement dispersion approaching the posterior vertebral margin; Second, the \u0026zwnj;radiographic warning threshold\u0026zwnj; (quantified as a percentage of sagittal diameter) to guide safe cement injection without compromising therapeutic efficacy. By correlating intraoperative fluoroscopic measurements with postoperative CT findings, we aim to establish evidence-based parameters for optimizing PKP safety while maintaining clinical effectiveness.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003ePatient selection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study subjects were selected from patients with OVCFs who underwent PKP surgery at our research institute between February 2018 and September 2022. \u003cstrong\u003eThe inclusion criteria\u003c/strong\u003e for patients were as follows: (1) osteoporotic thoracic or lumbar vertebral compression fractures with a bone density T score \u0026le; -1.0; (2) no preoperative neurological symptoms; (3) disease duration \u0026le; 3 weeks; (4) clear history of low back pain with a visual analogue scale (VAS) score \u0026ge; 4; (5) surgery performed by the same surgeon via unilateral puncture PKP; and (6) intraoperative X-ray fluoroscopy lateral images showing bone cement dispersion reaching or approaching the posterior vertebral edge, as measured by two doctors. \u003cstrong\u003eThe exclusion criteria were as follows:\u003c/strong\u003e (1) surgically confirmed infectious or pathological fractures; (2) congenital vertebral anomalies (e.g., hemivertebrae or congenital fusion vertebrae); (3) presence of preoperative neurological symptoms; (4) nonosteoporotic vertebral fractures; (5) inability to clearly identify the posterior vertebral wall for any reason; and (6) previous vertebral fractures or fractures with a disease duration \u0026gt; 3 weeks. A total of 88 patients (106 vertebral bodies) meeting these criteria were included.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSurgical Procedure\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients were positioned prone, and local anaesthesia was administered at the puncture site. Under X-ray fluoroscopy, the puncture needle and cannula were carefully inserted into the vertebral body. The puncture process should avoid areas close to cortical defects, especially those in the posterior vertebral wall. Balloon expansion and high-viscosity cement injection were performed under X-ray fluoroscopy, starting approximately 1 minute and 30 seconds after mixing. The degree of cement dispersion was closely monitored, and the injection was stopped if the cement approached or exceeded the posterior vertebral edge. Finally, the cement delivery device and cannula were removed, and the incision was compressed for hemostasis and covered with a dressing. All procedures were performed by the same surgeon via a unilateral puncture technique. Intraoperative X-ray fluoroscopy was used to ensure symmetrical pedicles in the anteroposterior view and parallel endplates in both the anteroposterior and lateral views.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eClinical baseline data, including age, sex, bone density, surgical segment, balloon pressure, contrast dose, and bone cement volume, were recorded during the perioperative period. The visual analog scale (VAS) score before and after surgery and postoperative neurological complications were recorded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRadiological measurement and indicators\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll 88 patients received postoperative three-dimensional (3D) CT scans of the thoracic/lumbar spine following PKP. DICOM datasets were reconstructed using advanced volumetric rendering techniques on a dedicated imaging workstation\u0026zwnj;. Intraoperative imaging modalities, including real-time X-ray fluoroscopy and CT acquisitions, were systematically archived for multimodal analysis\u0026zwnj;. \u0026zwnj;Intraoperative X-ray fluoroscopy images were reviewed to identify cases where bone cement dispersion extended near the posterior vertebral margin\u0026zwnj;. \u0026zwnj;Postoperative 3D axial CT images were utilized to measure the spatial distribution and volumetric extent of posterior vertebral wall leakage, applying standardized segmentation protocols\u0026zwnj;. \u0026zwnj;Group Classification\u0026zwnj;: \u0026zwnj;Group A\u0026zwnj;: Absence of cement leakage at the apex of posterior edge dispersion; \u0026zwnj;Group B\u0026zwnj;: Confirmed posterior wall leakage, defined as cement extravasation exceeding of the vertebral body volume\u0026zwnj;.\u003c/p\u003e\n\u003cp\u003ePatients were stratified into three groups based on sagittal dispersion patterns of bone cement relative to the posterior vertebral wall in intraoperative lateral X-ray fluoroscopy images: \u0026zwnj;Group I\u0026zwnj;: Bone cement dispersion edge localized to the upper third of the posterior vertebral wall; \u0026zwnj;Group II\u0026zwnj;: Dispersion edge confined to the middle third; \u0026zwnj;Group III\u0026zwnj;: Dispersion edge extending to the lower third. A quantitative analysis of posterior vertebral wall leakage was performed using three-dimensional (3D) CT reconstruction to evaluate cement migration patterns\u0026zwnj;\u003c/p\u003e\n\u003cp\u003eIn intraoperative lateral X-ray fluoroscopy images (\u003cstrong\u003eFig 1\u003c/strong\u003e): Line \u0026zwnj;a\u0026zwnj; corresponds to the posterior vertebral margin; Line \u0026zwnj;b\u0026zwnj; is drawn parallel to line \u0026zwnj;a\u0026zwnj;, passing through the apex of the posterior edge of bone cement dispersion, serving as the warning boundary for posterior cement spread; Line \u0026zwnj;c\u0026zwnj; represents the anterior vertebral margin. The distances \u0026zwnj;ab\u0026zwnj; (between lines a and b) and \u0026zwnj;ac\u0026zwnj; (between lines a and c) are measured to calculate the ratio \u0026zwnj;ab/ac. In reconstructed axial CT images (\u003cstrong\u003eFig 1\u003c/strong\u003e): Line \u0026zwnj;d\u0026zwnj; connects the bilateral cortical apexes of the posterior vertebral margin; Line \u0026zwnj;e\u0026zwnj; is drawn parallel to line \u0026zwnj;d\u0026zwnj; through the apex of the posterior vertebral concavity; Line \u0026zwnj;f\u0026zwnj; parallels line \u0026zwnj;d\u0026zwnj; and aligns with the anterior vertebral margin. The distances \u0026zwnj;de\u0026zwnj; (between lines d and e) and \u0026zwnj;df\u0026zwnj; (between lines d and f) are measured to derive the ratio \u0026zwnj;de/df\u0026zwnj;\u0026zwnj;. Comparative analysis demonstrates a significant correlation between the \u0026zwnj;ab/ac\u0026zwnj; ratio from X-ray fluoroscopy and the \u0026zwnj;de/df\u0026zwnj; ratio from CT axial imaging, suggesting these parameters may serve as complementary metrics for evaluating posterior bone cement dispersion patterns\u0026zwnj;.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analysis was performed via SPSS 19.0 software. The measurement data were first tested for normality. If the samples conformed to a normal distribution, an independent samples t test or analysis of variance (ANOVA) was used to compare the mean values across groups to determine if there were statistically significant differences. The significance level was set at \u0026alpha;=0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eClinical Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFrom February 2018 to September 2022, 88 eligible patients (19 males, 69 females) underwent unilateral PKP, involving 106 vertebral levels. No postoperative neurological complications were reported, and all patients completed preoperative and postoperative imaging evaluations. The cohort had a mean age of 73.58 \u0026plusmn; 9.59 years (range: 52\u0026ndash;89) and an average bone mineral density (BMD) T-score of -3.59 \u0026plusmn; 0.86 (range: -2.5 to -5.7). Fracture distribution across vertebral levels included T5 (1 case), T6 (2), T7 (2), T9 (4), T10 (4), T11 (13), T12 (31), L1 (17), L2 (22), L3 (6), and L4 (4). Single-segment fractures accounted for 73 cases, while 15 cases involved two or multiple segments. Preoperative visual analog scale (VAS) scores significantly decreased from 5.69 \u0026plusmn; 1.15 to 1.20 \u0026plusmn; 0.79 postoperatively (\u003cstrong\u003eTable 1\u003c/strong\u003e).\u0026zwnj;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eClinical data of all patients\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"548\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 283px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003eGeneral Data\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eTotal number\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eVertebra\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e106\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eMean age\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e73.58\u0026plusmn;9.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eMean BMD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e-3.59\u0026plusmn;0.86\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eFracture segment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eT12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eL1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eL2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eL3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eL4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eSingle-segment fracture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 284px;\"\u003e\n \u003cp\u003eDouble or multiple segment fractures\u003c/p\u003e\n \u003cp\u003ePreoperative VAS score\u003c/p\u003e\n \u003cp\u003ePostoperative VAS score\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e(VAS)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 265px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003cp\u003e5.69\u0026plusmn;1.15\u003c/p\u003e\n \u003cp\u003e1.20\u0026plusmn;0.79\u003c/p\u003e\n \u003cp\u003e0.00*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eRadiological\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePostoperative 3D CT reconstruction identified 44 cases in Group A and 62 cases in Group B with posterior vertebral wall cement leakage, demonstrating an overall incidence rate of 58.5%. Comparative analysis showed no statistically significant intergroup differences in demographic characteristics (sex, age) or procedural parameters including bone density, balloon pressure, contrast agent volume, and bone cement injection volume (all \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026gt; 0.05) (\u003cstrong\u003eTable 2\u003c/strong\u003e). \u0026zwnj;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Comparison between Group A and Group B\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003eBMD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003eBalloon pressure\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003eContrast agent volume\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003ebone cement volume\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e72.12\u0026plusmn;9.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e-3.76\u0026plusmn;0.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e189.03\u0026plusmn;48.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e2.85\u0026plusmn;0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e3.68\u0026plusmn;1.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e74.18\u0026plusmn;9.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e-3.52\u0026plusmn;0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e190.00\u0026plusmn;39.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e2.83\u0026plusmn;0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e3.47\u0026plusmn;1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e(F value, \u003cem\u003eP\u003c/em\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e(0.000, 0.317)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e(0.105, 0.187)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e(1.790, 0.914)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e(0.840, 0.811)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e(1.295, 0.331)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026Delta;There was no statistically significant difference, with \u003cem\u003eP\u003c/em\u003e\u0026gt;0.05.\u003c/p\u003e\n\u003cp\u003eBased on postoperative 3D CT scans, the posterior vertebral wall was subdivided into three equal segments. A total of 106 vertebral bodies were categorized into three groups according to bone cement distribution patterns within the posterior vertebral wall: Group I (upper third, n=8), Group II (middle third, n=95), and Group III (lower third, n=3). Cement leakage occurred in 25% (2/8) of Group I cases, 61.1% (58/95) of Group II cases, and 66.7% (2/3) of Group III cases, demonstrating statistically significant intergroup differences in leakage rates (\u003cem\u003eP\u003c/em\u003e\u0026lt;0.05). However, no significant differences were observed among groups regarding demographic characteristics (sex, age), bone density, or procedural parameters (balloon pressure, contrast agent volume, cement injection volume) (\u003cem\u003eP\u003c/em\u003e\u0026gt;0.05) (\u003cstrong\u003eTable 3\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3\u003c/strong\u003e Comparisons among groups I, II and III\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eBMD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eBalloon pressure\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eContrast agent volume\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003ebone cement volume\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eGroup I\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e76.00\u0026plusmn;8.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e-3.90\u0026plusmn;0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e202.50\u0026plusmn;58.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e2.56\u0026plusmn;0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e3.44\u0026plusmn;1.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eGroup II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e73.02\u0026plusmn;9.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e-3.57\u0026plusmn;0.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e188.00\u0026plusmn;40.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e2.85\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e3.52\u0026plusmn;1.02\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003eGroup III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e85.00\u0026plusmn;2.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e-3.53\u0026plusmn;0.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e210.00\u0026plusmn;30.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e3.00\u0026plusmn;0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e4.17\u0026plusmn;1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(F value, \u003cem\u003eP\u003c/em\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(2.623, 0.077)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(0.562, 0.572)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(0.805, 0.450)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(1.185,0.310)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 92px;\"\u003e\n \u003cp\u003e(0.590, 0.566)\u003csup\u003e\u0026Delta;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026Delta;There was no statistically significant difference, with \u003cem\u003eP\u003c/em\u003e\u0026gt;0.05.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWarning line in PKP surgery\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn Group A, comprising 44 vertebral bodies without intraoperative bone cement leakage, radiographic analysis demonstrated a mean ab/ac ratio of (6.8\u0026plusmn;2.17)% on intraoperative lateral X-ray imaging. Postoperative 3D CT reconstruction revealed a significantly higher de/df ratio of 11.19\u0026plusmn;3.47% in axial planes (\u003cem\u003eP\u003c/em\u003e\u0026lt;0.05)\u0026zwnj;. This statistical discrepancy highlights the critical importance of differentiating intraoperative fluoroscopic measurements from postoperative cross-sectional imaging assessments in vertebral augmentation procedures\u0026zwnj;.\u003c/p\u003e\n\u003cp\u003eThe study concludes that establishing a safety margin at approximately 6.8% of the vertebral body\u0026apos;s sagittal diameter from its posterior wall proves effective for preventing cement extravasation during PKP\u0026zwnj;. This spatial parameter, validated through comparative imaging modalities, corresponds to the optimal positioning of cement containment warning markers under real-time fluoroscopic guidance\u0026zwnj;. A representative clinical case illustrating this spatial relationship and surgical application is presented in \u003cstrong\u003eFig 2\u003c/strong\u003e, demonstrating successful cement containment within the proposed safety boundaries\u0026zwnj;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOVCFs are a common type of fragility fracture caused by decreased bone mass. Surgical treatment is a primary approach[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], aiming to quickly alleviate back pain, end prolonged bed rest, reduce the incidence of complications such as lower limb venous thrombosis, pneumonia, and pressure sores, and prevent muscle weakness or atrophy due to long-term bed rest, which can further exacerbate bone loss and osteoporosis. Among surgical treatments, PKP is widely applied for osteoporotic vertebral fractures[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Compared with traditional open surgery, PKP is advantageous because of its shorter duration, less trauma, minimal bleeding, and rapid symptom relief.\u003c/p\u003e \u003cp\u003eCement leakage remains the main complication of PKP, with an incidence rate of 25% reported in the literature[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Leakage into blood vessels or the spinal canal can lead to severe complications, including pulmonary embolism and spinal cord or nerve damage, significantly affecting surgical outcomes and reducing patients' quality of life[\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Therefore, to increase surgical safety, many risk factors for cement leakage have been identified, such as low bone density, hypertension, degree of vertebral compression, presence of vertebral fissures, and cement viscosity[\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. However, there is limited research on the early detection and prevention of leakage during surgery. It is challenging to detect early leakage through intraoperative X-ray fluoroscopic lateral views[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Wang et al. [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] noted that the anatomical feature of the posterior vertebral wall appearing arch shaped and concave inwards on axial CT images makes it difficult to detect cement leakage in a timely and accurate manner through X-ray fluoroscopy during surgery unless CT scans are performed intraoperatively. Yeom et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] reported that only 7% of intrathecal cement leakage could be detected via lateral views and suggested that cement injection be stopped immediately when it reaches one-fifth of the vertebral body via intraoperative fluoroscopy. However, this indicator is subjectively defined and not an objective measurement.\u003c/p\u003e \u003cp\u003eIn this study, cases where cement dispersion just reached the posterior edge without leakage were screened via axial postoperative spinal CT images. Measurements of CT axial images and intraoperative fluoroscopic lateral views revealed that the postoperative fluoroscopic measurement results were significantly smaller than the CT measurements were, indicating statistical significance. Zhang et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] precisely measured the depth of the posterior vertebral concavity via CT. We believe that CT measurements cannot fully represent intraoperative fluoroscopic images because of differences in defining the posterior vertebral edge between the two imaging methods. Intraoperative X-ray fluoroscopic images are more intuitive and immediately useful for reference during surgery. Therefore, on the basis of our study results, we suggest that in intraoperative X-ray fluoroscopic lateral views, the warning line for cement dispersion is approximately 6.8% of the sagittal diameter from the posterior vertebral edge.\u003c/p\u003e \u003cp\u003eIn actual cases, further observation of postoperative CT and X-ray images revealed that when the posterior vertebral wall was divided into thirds, cement leakage occurred mainly in the middle and lower thirds, with the lowest incidence in the upper third. These findings suggest that the vertebral venous foramen is a high-risk area for posterior vertebral wall cement leakage. Li et al. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] reported that the presence of the vertebral venous foramen and relatively sparse trabeculae make the middle region of the vertebral body mechanically weakest. During vertebral compression, the central trabeculae are most severely damaged, with the largest intertrabecular distance, thus resulting in the highest leakage rate [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. In some cases, although the degree of cement dispersion exceeded the posterior vertebral edge, further observation of axial postoperative CT images revealed that the cement did not leak into the spinal canal but rather dispersed into the pedicle, possibly explaining the lower incidence of upper third leakage. Therefore, when cement dispersion exceeds the warning line in the middle and lower thirds of the vertebral body, there is a greater risk of posterior wall leakage.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003ePKP demonstrates a favorable safety profile in managing OVCFs, though posterior vertebral wall cement leakage remains a notable concern. This study revealed a 58.5% incidence of posterior wall leakage, with most occurrences localized to the middle and lower thirds of the vertebral posterior wall\u0026zwnj;. Radiographic analysis established a critical safety boundary at 6.8% of the vertebral sagittal diameter from the posterior margin, serving as an intraoperative fluoroscopic guide for cement dispersion monitoring\u0026zwnj;. Clinical observations indicate significantly reduced leakage rates when cement diffusion apex remains anterior to this threshold during PKP procedures. This safety boundary proves effective in mitigating cement extravasation risks and associated complications. Imaging analysis further highlights elevated leakage risks when cement extends beyond the warning line, particularly in the middle and lower vertebral thirds. These findings emphasize the importance of real-time radiographic monitoring and strict adherence to the 6.8% sagittal diameter guideline for optimizing surgical outcomes\u0026zwnj;.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eOVCFs: Osteoporotic vertebral compression fractures; PKP: Percutaneous kyphoplasty; VAS: Visual analog scale; ANOVA: Analysis of variance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study involving human participants was conducted in accordance with the \u0026zwnj;Declaration of Helsinki\u0026zwnj; and approved by the \u0026zwnj;ethics committee of Beijing Chaoyang Hospital Affiliated to Capital Medical University. All participants provided written informed consent, and procedures adhered to institutional ethical standards for human subject research\u0026zwnj;.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data used and analyzed during this study are available from the corresponding author upon reasonable request.\u0026nbsp;\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.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDongyue Li\u0026zwnj;: Conceptualized the study design, authored the manuscript, and drafted of the paper\u0026zwnj;. Luming Tao\u0026zwnj;: Conducted data collection and performed statistical analysis\u0026zwnj;. Xinuo Zhang\u0026zwnj;: Collaborated in data interpretation and revised the manuscript\u0026zwnj;. Qingjun Su\u0026zwnj;: Contributed to the study\u0026rsquo;s methodological framework, oversaw project revisions, and provided supervisory oversight throughout the research process\u0026zwnj;.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to thank all the participants in the studies.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eGauthier A, Kanis JA, Jiang Y, et al. Epidemiological burden of postmenopausal osteoporosis in the UK from 2010 to 2021: estimations from a disease model[J]. Arch Osteoporos, 2011,6:179-188. doi:10.1007/s11657-011-0063-y\u003c/li\u003e\n\u003cli\u003eSemaan H, Obri T, Bazerbashi M, et al. Clinical outcome and subsequent sequelae of cement extravasation after percutaneous kyphoplasty and vertebroplasty: a comparative review[J]. Acta Radiol,2018,59(7):861-868. doi:10.1177/0284185117732599\u003c/li\u003e\n\u003cli\u003eHuang SH, Zhu XW, Xiao D, et al. Therapeutic effect of percutaneous kyphoplasty combined with anti-osteoporosis drug on postmenopausal women with osteoporotic vertebral compression fracture and analysis of postoperative bone cement leakage risk factors: a retrospective cohort study[J]. J Orthop Surg Res, 2019,14(1):452. doi:10.1186/s13018-019-1499-9\u003c/li\u003e\n\u003cli\u003eLD Rose, G Bateman, A Ahmed. Clinical significance of cement leakage in kyphoplasty and vertebroplasty: a systematic review[J]. Eur Spine J, 2024,33(4):1484-1489. doi: 10.1007/s00586-023-08026-3.\u003c/li\u003e\n\u003cli\u003eFadili Hassani S, Cormier E, Shotar E, et al. Intracardiac cement embolism during percutaneous vertebroplasty: incidence, risk factors and clinical management[J]. Eur Radiol,2019,29(2):663-73. doi:10.1007/s00330-018-5647-0\u003c/li\u003e\n\u003cli\u003eShridhar P, Chen Y, Khalil R, et al. A Review of PMMA Bone Cement and Intra-Cardiac Embolism[J]. Materials(Basel), 2016,9(10):821. doi:10.3390/ma9100821\u003c/li\u003e\n\u003cli\u003eRen H, Feng T, Cao J, et al. A Retrospective Study to Evaluate the Effect of Dynamic Fracture Mobility on Cement Leakage in Percutaneous Vertebroplasty and Percutaneous Kyphoplasty in 286 Patients with Osteoporotic Vertebral Compression Fractures[J]. Med Sci Monit, 2022,28:e935080. doi:10.12659/MSM.935080 \u003c/li\u003e\n\u003cli\u003eWang C, Fan S, Liu J, et al. Basivertebral foramen could be connected with intravertebral cleft: a potential risk factor of cement leakage in percutaneous kyphoplasty[J]. Spine J, 2014,14(8):1551-1558. doi:10.1016/j.spinee.2013.09.025 \u003c/li\u003e\n\u003cli\u003eZhang S, Wang GJ, Wang Q, et al. A mysterious risk factor for bone cement leakage into the spinal canal through the Batson vein during percutaneous kyphoplasty: a case control study[J]. BMC Musculoskelet Disord, 2019,20(1):423. doi:10.1186/s12891-019-2807-6\u003c/li\u003e\n\u003cli\u003eHsieh MK, Kao FC, Chiu PY, et al. Risk factors of neurological deficit and pulmonary cement embolism after percutaneous vertebroplasty[J]. J Orthop Surg Res, 2019, 14(1):406. doi:10.1186/s13018-019-1459-4\u003c/li\u003e\n\u003cli\u003eTang C, Tang X, Zhang W, et al. Percutaneous mesh-container-plasty for osteoporotic thoracolumbar burst fractures: A prospective, nonrandomized comparative study[J]. Acta Orthop Traumatol Turc, 2021,55(1):22-27. doi:10.5152/j.aott.2021.20045\u003c/li\u003e\n\u003cli\u003eYin P, Li Z, Zhu S, et al. The treatment of osteoporotic thoraco-lumbar burst fractures by unilateral percutaneous kyphoplasty: A prospective observation study[J]. Eur J Pain, 2020,24(3):659-664. doi:10.1002/ejp.1516\u003c/li\u003e\n\u003cli\u003ePhillips FM, Todd Wetzel F, Lieberman I, et al. An in vivo comparison of the potential for extravertebral cement leak after vertebroplasty and kyphoplasty[J]. Spine (Phila Pa 1976), 2002,27(19):2173-2178. doi:10.1097/00007632-200210010-00018\u003c/li\u003e\n\u003cli\u003eHarrington KD. Major neurological complications following percutaneous vertebroplasty with polymethylmethacrylate : a case report[J]. J Bone Joint Surg Am, 2001,83(7):1070-1073. doi:10.2106/00004623-200107000-00014\u003c/li\u003e\n\u003cli\u003eYoo KY, Jeong SW, Yoon W, et al. Acute respiratory distress syndrome associated with pulmonary cement embolism following percutaneous vertebroplasty with polymethylmethacrylate[J]. Spine (Phila Pa 1976), 2004,29(14):E294-297. doi:10.1097/01.brs.0000131211.87594.b0\u003c/li\u003e\n\u003cli\u003eLee ST, Chen JF. Closed reduction vertebroplasty for the treatment of osteoporotic vertebral compression fractures. Technical note[J]. J Neurosurg, 2004,100(4 Suppl Spine):392-396. doi:10.3171/spi.2004.100.4.0392\u003c/li\u003e\n\u003cli\u003eRho YJ, Choe WJ, Chun YI. Risk factors predicting the new symptomatic vertebral compression fractures after percutaneous vertebroplasty or kyphoplasty[J]. Eur Spine J, 2012,21(5):905-911. doi:10.1007/s00586-011-2099-5\u003c/li\u003e\n\u003cli\u003eLi M, Zhang T, Zhang R, et al. Systematic Retrospective Analysis of Risk Factors and Preventive Measures of Bone Cement Leakage in Percutaneous Kyphoplasty[J]. World Neurosurg, 2023,171:e828-836. doi:10.1016/j.wneu.2022.12.117 \u003c/li\u003e\n\u003cli\u003eXu DL, Ruan CY, Wang Y, et al. Comparison of the clinical effect of unilateral transverse process extrapedicular and bilateral transpedicular percutaneous kyphoplasty for thoracolumbar osteoporotic vertebral compression fracture[J]. Front Surg, 2024,11: 1395289. doi: 10.3389/fsurg.2024.1395289. eCollection 2024\u003c/li\u003e\n\u003cli\u003eYeom JS, Kim WJ, Choy WS, et al. Leakage of cement in percutaneous transpedicular vertebroplasty for painful osteoporotic compression fractures[J]. J Bone Joint Surg Br, 2003,85(1):83-89. doi:10.1302/0301-620x.85b1.13026\u003c/li\u003e\n\u003cli\u003eLi S, Wang C, Shan Z, et al. Trabecular Microstructure and Damage Affect Cement Leakage From the Basivertebral Foramen During Vertebral Augmentation[J]. Spine (Phila Pa 1976), 2017,42(16):E939-948. doi:10.1097/BRS.0000000000002073\u003c/li\u003e\n\u003cli\u003eFang N, Wang TY, Wang AB, et al.A predictive nomogram for intradiscal cement leakage in percutaneous kyphoplasty for osteoporotic vertebral compression fractures combined with intravertebral cleft[J].Front Surg, 2022,9:1005220. doi:10.3389/fsurg.2022.1005220. eCollection 2022.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Percutaneous kyphoplasty (PKP), Osteoporotic vertebral compression fractures (OVCFs), Bone cement leakage, Radiographic warning line","lastPublishedDoi":"10.21203/rs.3.rs-6157948/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6157948/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e‌\u003cstrong\u003eBackground\u003c/strong\u003e‌ With the global aging population, osteoporotic fractures—particularly osteoporotic vertebral compression fractures (OVCFs)—have emerged as a critical health concern, severely impacting the quality of life in elderly individuals. Percutaneous kyphoplasty (PKP) has demonstrated significant clinical efficacy in treating OVCFs by stabilizing fractures and alleviating pain‌. However, bone cement leakage during PKP remains a major complication, posing risks of spinal cord compression. This study aimed to establish a radiographic \"warning line\" to predict and mitigate posterior vertebral wall cement leakage during PKP.\u003c/p\u003e\n\u003cp\u003e‌\u003cstrong\u003eMethods‌ \u003c/strong\u003eFrom February 2018 to September 2022, 88 patients (106 vertebral bodies) with OVCFs treated by unilateral PKP at a single center were retrospectively analyzed. Inclusion criteria required intraoperative X-ray confirmation of bone cement diffusion reaching the posterior vertebral margin. Postoperative three-dimensional CT scans classified vertebrae into Group A (no leakage, n=44) and Group B (leakage, n=62). Parameters including age, bone mineral density (T-score), balloon pressure, contrast volume, and cement volume were compared. The posterior vertebral wall was divided into upper, middle, and lower thirds to assess leakage distribution. Lateral X-ray measurements defined the warning line (line b) as the apex of cement diffusion parallel to the posterior vertebral margin (line a), with the ratio ab/ac calculated to quantify its position relative to the sagittal diameter.\u003c/p\u003e\n\u003cp\u003e‌\u003cstrong\u003eResults‌ \u003c/strong\u003eAll patients exhibited significant pain relief (preoperative VAS: 5.69±1.15 vs. postoperative: 1.20±0.79, \u003cem\u003eP\u003c/em\u003e\u0026lt;0.05) without neurological complications. Posterior vertebral wall leakage occurred in 58.5% (62/106) of cases, predominantly in the middle (61.1%) and lower thirds (66.7%) (P\u0026lt;0.05)‌. No significant differences existed between groups in age, bone density, or procedural parameters (\u003cem\u003eP\u003c/em\u003e\u0026gt;0.05). The warning line ratio (ab/ac) in Group A was 6.8±2.17%, indicating that maintaining cement diffusion anterior to this threshold correlated with reduced leakage risk.\u003c/p\u003e\n\u003cp\u003e‌\u003cstrong\u003eConclusions‌ \u003c/strong\u003ePKP is a safe and effective intervention for OVCFs, but posterior vertebral wall leakage remains prevalent. Cement dispersion exceeding 6.8% of the sagittal diameter from the posterior margin significantly increases leakage risk, particularly in the middle and lower thirds of the vertebral wall‌. The proposed warning line provides a practical intraoperative radiographic marker to enhance procedural safety and reduce complications.\u003c/p\u003e","manuscriptTitle":"Percutaneous Kyphoplasty Warning Line for Preventing Bone Cement Leakage","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-17 09:37:47","doi":"10.21203/rs.3.rs-6157948/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"874ad154-5cde-4ecf-8e60-cff3c724e378","owner":[],"postedDate":"April 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-10T12:25:21+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-17 09:37:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6157948","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6157948","identity":"rs-6157948","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}