Risk factors for predicting cement leakage following percutaneous vertebroplasty for osteoporotic vertebral compression fractures

A novel assessment system for osteoporotic vertebral compression fractures

The objective of this study was to introduce and validate a novel developed scoring system tailored specifically for osteoporotic vertebral compression fractures (OVCFs), aiming to provide guidance for treatment selection. A retrospective analysis spanning from March 2016 to March 2021 was conducted on 208 patients diagnosed with osteoporotic vertebral compression fractures (OVCFs) who received conservative treatment. Patients were categorized into low-score (47 cases), medium-score (98 cases), and high-score (63 cases) groups based on the Novel Assessment System for OVCFs (NASOVCF) scores. Comparative analyses of radiographic and clinical data were performed, and logistic regression analysis was used to determine the risk factors for bone non-union and progressive kyphosis. The high-score group exhibited significantly inferior outcomes, characterized by higher Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores (P < 0.05), increased vertebral height loss, and kyphosis angle differences compared to the low and medium-score groups (P < 0.05). Notably, a bone union rate of 38.1% (24/63) was observed in the high-score group, significantly lower than that of the low-score group (97.9%, 46/47). Furthermore, the progressive kyphosis rate was 47.6% (30/63) in the high-score group, significantly higher than the 17.3% (17/98) observed in the medium-score group and the 2.2% (1/46) observed in the low-score group. In multivariate analysis, higher NASOVCF score emerged as an independent risk factor for bone non-union (OR = 1.713, 95% CI 1.458-2.013, P < 0.001). Similarly, higher NASOVCF score (OR = 1.373, 95% CI 1.203-1.568, P < 0.001), along with female gender and higher pre-treatment ODI score, were identified as independent risk factors for progressive kyphosis. The area under the curve (AUC) for bone non-union and progressive kyphosis were 0.895 and 0.835, respectively, indicating robust discriminative performances. Higher NASOVCF score was identified as a significant risk factor for non-union and progressive kyphosis following conservative treatment in OVCFs. NASOVCF score emerged as a crucial predictor for adverse outcomes in patients at high risk who underwent conservative management. Surgical interventions such as vertebral augmentation may represent a potentially superior option for individuals with high NASOVCF scores.

Cement Leakage after Augmentation of Osteoporotic Vertebral Bodies

Der Zementaustritt ist die häufigste Komplikation bei der Zementaugmentation von Wirbelkörpern. In der vorliegenden Studie wurden die Zementaustrittsraten bei Zementaugmentationen an der Wirbelsäule untersucht und potenzielle Risikofaktoren für einen Zementaustritt identifiziert.Es wurden 140 Fälle von 131 Patienten und Patientinnen und 9 Verstorbenen ausgewertet. Insgesamt wurden 258 zementaugmentierte Wirbelkörper untersucht. Die Daten dafür stammen aus den Krankenhausdokumentationen von 131 Patienten und Patientinnen, die sich in 2 orthopädisch-unfallchirurgischen Kliniken in der BRD solchen Operationen unterzogen, sowie aus den Untersuchungen von 9 Sterbefällen im Institut für Rechtsmedizin der Universitätsklinikums Hamburg-Eppendorf.Zementaustritte wurden in 64 der 140 Fälle (45,7%) ermittelt. Lokale Zementaustritte waren mit 73,4% (n = 47) die häufigste Austrittsart. Venöse Austritte wurden in 15 Fällen (23,4%) und Lungenzementembolisationen in 2 Fällen (3,1%) evaluiert. Innerhalb des Kollektivs der retrospektiv untersuchten Fälle (n = 131) erlitt lediglich 1 Patient (0,8%) einen symptomatischen Zementaustritt. Als Risikofaktoren für Zementaustritte konnten Zementaugmentationen von Frakturen an Lendenwirbelkörpern sowie eine hohe applizierte Zementmenge identifiziert werden.Sowohl die Daten in der assoziierten Literatur als auch die Ergebnisse dieser Arbeit belegen eine hohe Inzidenz von Zementaustritten nach Wirbelkörperaugmentationen. Trotz des geringen prozentualen Anteils symptomatischer Fälle sollten bei der Planung und Durchführung von Zementaugmentationen an Wirbelkörpern die möglichen Einflussfaktoren für einen Zementaustritt berücksichtigt und in die OP-Planung einbezogen werden.

Interpretable Machine Learning Model to Predict Bone Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fracture Based on SHapley Additive exPlanations

STUDY DESIGN

Retrospective study.

OBJECTIVES

Our objective is to create comprehensible machine learning (ML) models that can forecast bone cement leakage in percutaneous vertebral augmentation (PVA) for individuals with osteoporotic vertebral compression fracture (OVCF) while also identifying the associated risk factors.

METHODS

We incorporated data from patients (n = 425) which underwent PVA. To predict cement leakage, we devised six models based on a variety of parameters. Evaluate and juxtapose the predictive performances relied on measures of discrimination, calibration, and clinical utility. SHapley Additive exPlanations (SHAP) methodology was used to interpret model and evaluate the risk factors associated with cement leakage.

RESULTS

The occurrence rate of cement leakage was established at 50.4%. A binary logistic regression analysis identified cortical disruption (OR 6.880, 95% CI 4.209-11.246), the basivertebral foramen sign (OR 2.142, 95% CI 1.303-3.521), the fracture type (OR 1.683, 95% CI 1.083-2.617), and the volume of bone cement (OR 1.198, 95% CI 1.070-1.341) as independent predictors of cement leakage. The XGBoost model outperformed all others in predicting cement leakage in the testing set, with AUC of .8819, accuracy of .8025, recall score of .7872, F1 score of .8315, and a precision score of .881. Several important factors related to cement leakage were drawn based on the analysis of SHAP values and their clinical significance.

CONCLUSION

The ML based predictive model demonstrated significant accuracy in forecasting bone cement leakage for patients with OVCF undergoing PVA. When combined with SHAP, ML facilitated a personalized prediction and offered a visual interpretation of feature importance.

Risk factors for cement leakage after percutaneous vertebral augmentation for osteoporotic vertebral compression fractures: a meta-analysis

BACKGROUND

Osteoporotic vertebral compression fractures (OVCF) may necessitate percutaneous vertebral augmentation (PVA), a procedure not without its risks. One notable complication is cement leakage (CL), which can cause significant distress in patients. Despite its clinical importance, there remains a paucity of meta-analyses investigating these complications and their management in the existing literature.

MATERIAL AND METHODS

The authors systematically reviewed PubMed, Cochrane Library, Embase, and Web of Science databases up to February 2024 to identify studies examining CL following PVA treatment in OVCF. The authors assessed the quality of eligible cohort studies using the Newcastle-Ottawa Scale (NOS), extracted data on incidence, identified risk factors for CL, and conducting meta-analysis with Revman 5.2 software. The authors calculated odd ratios (OR) and mean differences (MD) with 95% CI applying random-effects models.

RESULTS

The authors identified twelve cohort studies that matched our strict inclusion criteria. These studies included a total of 2388 patients and 3392 vertebrae. CL was identified in 1132 vertebrae. Notable risk factors for CL included compromised cortical bone integrity (OR 5.00, 95% CI 3.01-8.29, P <0.00001), presence of intravertebral vacuum clefts (OR 1.68, 95% CI 1.07-2.65, P =0.03), basivertebral foramen sign (OR 1.77, 95% CI 1.09-2.89, P =0.02), and volume of cement used (MD 0.75, 95% CI 0.41-1.10, P <0.0001).

CONCLUSION

The authors' findings underscore the significance of cortical bone integrity, intravertebral vacuum cleft, basivertebral foramen sign, and cement volume as principal determinants of CL risk in PVA for OVCF. These insights advocate for tailored surgical strategies to mitigate the risk of CL in this patient population.

Effect of Robot-Assisted Surgery on Clinical Outcomes in Patients with Osteoporotic Vertebral Compression Fractures after Percutaneous Vertebral Augmentation: a Meta-Analysis and a Validation Cohort

Background

The objective of this study was to investigate the impact of robot-assisted surgery (RA) on the risk of new vertebral compression fracture (NVCF) and bone cement leakage in patients with osteoporotic vertebral compression fractures (OVCF) after percutaneous vertebral augmentation (PVA), including percutaneous kyphoplasty (PKP) and percutaneous vertebroplasty (PVP).

Methods

A meta-analysis was performed to evaluate the clinical outcomes and adverse effects of RA-PVA versus fluoroscopy-assisted (FA)-PVA in patients with OVCF. A validation cohort of 385 patients who underwent PVP or PKP was retrospectively analyzed. In addition, we attempted to create well-calibrated nomograms to estimate the risk of NVCF and bone cement leakage.

Results

The meta-analysis revealed that the incidence of NVCF and bone cement leakage was significantly lower in RA-PVA than in FA-PVA. The validation cohort confirmed that RA-PVA provided better results than FA-PVA in terms of NVCF and bone cement leakage.

Conclusions

The meta-analysis and the validation cohort suggest that RA reduced the risk of NVCF and bone cement leakage in patients with OVCF after PVA. The nomograms are accurate and easy-to-implement methods for clinicians to estimate the risk of NVCF and bone cement leakage after PVA.

Development of patient-tailored preoperative assessment of percutaneous vertebroplasty

Percutaneous vertebroplasty (PVP), a minimally invasive surgery technique, has become the common treatment for osteoporotic vertebral compression fractures (OVCF). The complications of PVP will lead to severe damage to spinal neuro systems due to bone cement leakage. A patient tailored preoperative assessment approach was developed to reduce the risks of complications in this study. The porcine OVCF model was fabricated to mimic the patient vertebral fracture in vitro using decalcification process. The 3D reconstructed model based on the imagological examination data acquired from the porcine vertebral bone was implemented for finite element (FE) simulation. The vertebral body with bone cement injected was scanned using CT for comparison with the finite element simulation results. This study showed a practical method for predicting the flow of bone cement in OVCF, which enabled the surgeons to evaluate the bone cement flow during preoperative assessment to reduce the cement leakage risks.

Deep learning-based multimodal image analysis predicts bone cement leakage during percutaneous kyphoplasty: protocol for model development, and validation by prospective and external datasets

Background

Bone cement leakage (BCL) is one of the most prevalent complications of percutaneous kyphoplasty (PKP) for treating osteoporotic vertebral compression fracture (OVCF), which may result in severe secondary complications and poor outcomes. Previous studies employed several traditional machine learning (ML) models to predict BCL preoperatively, but effective and intelligent methods to bridge the distance between current models and real-life clinical applications remain lacking.

Methods

We will develop a deep learning (DL)-based prediction model that directly analyzes preoperative computed tomography (CT) and magnetic resonance imaging (MRI) of patients with OVCF to accurately predict BCL occurrence and classification during PKP. This retrospective study includes a retrospective internal dataset for DL model training and validation, a prospective internal dataset, and a cross-center external dataset for model testing. We will evaluate not only model's predictive performance, but also its reliability by calculating its consistency with reference standards and comparing it with that of clinician prediction.

Discussion

The model holds an imperative clinical significance. Clinicians can formulate more targeted treatment strategies to minimize the incidence of BCL, thereby improving clinical outcomes by preoperatively identifying patients at high risk for each BCL subtype. In particular, the model holds great potential to be extended and applied in remote areas where medical resources are relatively scarce so that more patients can benefit from quality perioperative evaluation and management strategies. Moreover, the model will efficiently promote information sharing and decision-making between clinicians and patients, thereby increasing the overall quality of healthcare services.

Efficacy and Safety of High-Viscosity Bone Cement in Percutaneous Vertebroplasty for Kummell's Disease

Background

To analyze and evaluate the clinical outcomes of using high-viscosity bone cement compared to low-viscosity bone cement in percutaneous vertebroplasty (PVP) for treatment of Kummell's disease.

Methods

From July 2017 to July 2019, 68 Kummell's disease patients who underwent PVP were chosen and separated into 2 groups: H group (n = 34), were treated with high-viscosity bone cement and L group (n = 34), treated with low-viscosity bone cement during treatment. The operation time, number of fluoroscopy tests done, and amount of bone cement perfusion were recorded for both groups. Clinical outcomes were compared, by measuring their Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Kyphosis Cobb's angle, vertebral height compression rate, and other complications.

Results

High-viscosity group showed less operation time and reduced number of fluoroscopy tests than the low-viscosity group (P < 0.05). When compared to preoperative period, both groups' VAS and ODI scores were significantly reduced at 1 day and 1 year postoperatively (P < 0.05). The vertebral height compression rate and Cobb's angle were significantly lower (P < 0.05) in both groups after surgery compared with those before surgery (P < 0.05). The cement leakage rate in group H was 26.5%, which was significantly lower than that in group L, which was 61.8% (P < 0.05).

Conclusions

High-viscosity and low-viscosity bone cement in PVP have similar clinical efficacy in reducing pain in patients during the treatment, but in contrast, high-viscosity bone cement shortens the operative time, reduces number of fluoroscopy views and vertebral cement leakage and improves surgical safety.

Incidence of Cement Leakage and Potential Risk Factors in Surgery for Spinal Metastasis: A Systematic Review and Meta-Analysis

OBJECTIVES

The current meta-analysis was performed to gather available evidence regarding the incidence and risk factors of cement leakage (CL) in patients undergoing surgical procedures for spinal metastasis.

METHODS

Two authors independently searched the PubMed, Embase, and CENTRAL databases. Clinical studies reporting the incidence or risk factors of CL were included for analysis. The primary outcome analyzed was the incidence of various types of CL. Random-effects or fixed-effects single-proportion meta-analyses were conducted to pool the available evidence, based on the heterogeneity test. Subgroup analyses were conducted based on surgical procedures (percutaneous vertebroplasty, percutaneous kyphoplasty, and others). Risk factors of CL were synthesized narratively to identify the most commonly accepted factors.

RESULTS

A total of 26 studies, involving 2551 patients, were included. The number of operated spine segments was reported in 23 studies, accounting for 4101 vertebrae. The pooled incidences of general, intradiscal, paravertebral, spinal canal, and intravascular CLs were 0.18 (95% confidence interval [CI], 0.11-0.28), 0.14 (95% CI, 0.08-0.21), 0.13 (95% CI, 0.06-0.21), 0.11 (95% CI, 0.05-0.19), and 0.12 (95% CI, 0.08-0.17), respectively. Subgroup analyses revealed significantly different incidences of general CL (0.37 vs. 0.06 vs. 0.09, P < 0.01), intradiscal CL (0.22 vs. 0.06 vs. 0.12, P < 0.01), paravertebral CL (0.25 vs. 0.03 vs. 0.06, P < 0.01), and vascular CL (0.14 vs. 0.03 vs. 0.15, P < 0.01) among the three groups. Posterior wall disruption, pathologic fracture, and the number of treated vertebral levels were the most commonly identified independent risk factors for general CL. Posterior wall disruption was determined as a common significant risk factor for spinal canal CL.

CONCLUSIONS

This review provides insights into the incidence and risk factors associated with CL in surgical procedures for spinal metastasis. Understanding these risk factors can contribute to the development of tailored strategies aimed at minimizing CL occurrence and optimizing surgical outcomes for patients undergoing spinal metastatic surgery.

Effects of Percutaneous Kyphoplasty for the Treatment of Thoracic Osteoporotic Vertebral Compression Fractures with or without Intravertebral Cleft in Elderly Patients

Background

Few studies have focused on percutaneous kyphoplasty (PKP) in the treatment of thoracic osteoporotic vertebral compression fractures (OVCFs) with intervertebral cleft (IVC). Hence, the objective of this retrospective study was to compare the clinical and radiographic outcomes of PKP in elderly patients with thoracic OVCFs, with or without IVC.

Methods

A total of 106 patients were enrolled in this study and divided into two groups: the IVC group and the NIVC group (without IVC). Radiographic measures included anterior vertebral height (AVH), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Clinical function measures included Oswestry disability index (ODI) and visual analog scale (VAS) scores.

Results

There were no significant differences in the preoperative basic data between the groups classified as IVC and NIVC. However, both groups showed significant improvements in AVH and TK throughout the follow-up periods compared to the preoperative measurements (P<0.05). The recovery of AVH in the IVC group was found to be inferior to that in the NIVC group at 3 years after operation (P<0.05). There were no significant differences in LL, PI, PT and SS in both groups compared with the preoperative results and no statistically significant differences between the two groups at the same follow-up time (P>0.05). The VAS and ODI scores during all follow-up periods were significantly lower than those before operation (P<0.05). At 3 years after operation, the VAS and ODI scores of the IVC group were higher than those of the NIVC group (P<0.05).

Conclusion

PKP is an adoptable measure to treat thoracic OVCFs with or without IVC. Our study revealed that the NIVC group was superior to the IVC group in terms of improved vertebral height and pain recovery at long-term follow-up (3 years).

Assessment of Cement Leakage in Decompressed Percutaneous Kyphoplasty

Symptomatic osteoporotic compression fractures are commonly addressed through vertebroplasty and kyphoplasty. However, cement leakage poses a significant risk of neurological damage. We introduced "aspiration percutaneous kyphoplasty", also known as "decompressed kyphoplasty", as a method to mitigate cement leakage and conducted a comparative analysis with high viscosity cement vertebroplasty. We conducted a retrospective study that included 136 patients with single-level osteoporotic compression fractures. Among them, 70 patients underwent high viscosity cement vertebroplasty, while 66 patients received decompressed percutaneous kyphoplasty with low-viscosity cement. Comparison parameters included cement leakage rates, kyphotic angle alterations, and the occurrence of adjacent segment fractures. The overall cement leakage rate favored the decompressed kyphoplasty group (9.1% vs. 18.6%), although statistical significance was not achieved (p = 0.111). Nonetheless, the risk of intradiscal leakage significantly reduced in the decompressed kyphoplasty cohort (p = 0.011), which was particularly evident in cases lacking the preoperative cleft sign on X-rays. Kyphotic angle changes and the risk of adjacent segment collapse exhibited similar outcomes (p = 0.739 and 0.522, respectively). We concluded that decompressed kyphoplasty demonstrates efficacy in reducing intradiscal cement leakage, particularly benefiting patients without the preoperative cleft sign on X-rays by preventing intradiscal leakage.

Evaluation of multidetector CT Hounsfield unit measurements as a predictor of efficacy and complications in percutaneous vertebroplasty for osteoporotic vertebral compression fractures

Introduction

More than 30 years after the initial experience of Galibert and Deramond with percutaneous vertebroplasty, the procedure has gone through countless refinements and clinical evaluations. Predictors for the success and failure of the procedure in the literature vary and are focused on the duration of complaints, type of fracture, presence of edema on MRI scans, etc. We propose using a quantitative method based on a standard CT examination of the thoracic or lumbar spine to assess the risks and potential success of performing vertebroplasty.

Materials and methods

This is a single-center prospective observational study on 139 patients treated with percutaneous vertebroplasty (pVPL) for a single symptomatic osteoporotic vertebral compression fracture (OVCF). We measured the levels of disability and pain preoperatively and again at the 3-, 6- and 12-month marks using the standardized VAS and ODI questionnaires. Every patient in the study was evaluated with postoperative multidetector CT (MDCT) to determine the presence, extent, and localization of vertebral cement leakage and to measure the adjacent vertebrae's minimal and mean density in Hounsfield units (HUmin and HUmean, respectively).

Results

We determined that a slight (r = -0.201) but statistically significant (p = 0.018) correlation existed between HU measurements taken from radiologically intact adjacent vertebrae and the procedure's effect concerning the pain levels at the 3-month follow-up. This correlation failed to reach statistical significance at 12 months (p = 0.072). We found no statistically significant relationship between low vertebral cancellous bone density and cement leakage on postoperative scans (p = 0.6 for HUmin and p = 0.74 for HUmean).

Conclusion

We have moderately strong data that show a negative correlation between the mean values of vertebral cancellous bone density in patients with OVCF and the effect of pVPL in reducing pain. Lower bone densities, measured this way, showed no increased risk of cement leakage.

Complication Pattern After Percutaneous Cement Discoplasty: Identification of Factors Influencing Reoperation and Length of Hospital Stay

OBJECTIVE

Percutaneous cement discoplasty (PCD) was introduced to treat symptomatic vertical instability of the lumbar spine in a minimally invasive way. The aim of the present study was to analyze the complication pattern after PCD and to identify factors that predict the chance of cement leakage, reoperation, and length of hospital stay (LOS).

METHODS

patients were treated with PCD within the study period. Clinical features and complications were analyzed by applying descriptive statistics, whereas perioperative factors predictive of cement leakage, reoperation, and LOS were identified by regression models.

RESULTS

Cement leakage rate was 30.4% in the total cohort; however, only fifth of them were symptomatic. Cement leakage itself did not have a significant influence on clinical outcome. Other complications and nonsurgical adverse events were registered only in 2.0% of cases. Age, subcutaneous fat tissue thickness, low viscosity cement, lower level of surgeon's experience and the number of operated levels were identified as risk factors of cement leakage (P < 0.01; c-index = 0.836). Type of procedure, Charlson comorbidity score, reoperation, and nonsurgical adverse events significantly increased the LOS (P < 0.01). Cement leakage, early surgical practice, and increased subcutaneous fat tissue thickness were risk factors for reoperation (P < 0.01; c-index = 0.72).

CONCLUSIONS

PCD is a relatively safe and effective procedure for treating spinal instability caused by advanced-stage disc degeneration characterized by vacuum phenomenon. Cement leakage is not uncommon but is only a radiologic complication without clinical consequences in most cases. On the other hand, it can increase the LOS and is a significant risk factor for reoperation.

Development of a nomogram model for prediction of new adjacent vertebral compression fractures after vertebroplasty

BACKGROUND

Vertebroplasty is the main minimally invasive operation for osteoporotic vertebral compression fracture (OVCF), which has the advantages of rapid pain relief and shorter recovery time. However, new adjacent vertebral compression fracture (AVCF) occurs frequently after vertebroplasty. The purpose of this study was to investigate the risk factors of AVCF and establish a clinical prediction model.

METHODS

We retrospectively collected the clinical data of patients who underwent vertebroplasty in our hospital from June 2018 to December 2019. The patients were divided into a non-refracture group (289 cases) and a refracture group (43 cases) according to the occurrence of AVCF. The independent predictive factors for postoperative new AVCF were determined by univariate analysis, least absolute shrinkage and selection operator (LASSO) logistic regression, and multivariable logistic regression analysis. A nomogram clinical prediction model was established based on relevant risk factors, and the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA) were used to evaluate the prediction effect and clinical value of the model. After internal validation, patients who underwent vertebroplasty in our hospital from January 2020 to December 2020, including a non-refracture group (156 cases) and a refracture group (21 cases), were included as the validation cohort to evaluate the prediction model again.

RESULTS

Three independent risk factors of low bone mass density (BMD), leakage of bone cement and "O" shaped distribution of bone cement were screened out by LASSO regression and logistic regression analysis. The area under the curve (AUC) of the model in the training cohort and the validation cohort was 0.848 (95%CI: 0.786-0.909) and 0.867 (95%CI: 0.796-0.939), respectively, showing good predictive ability. The calibration curves showed the correlation between prediction and actual status. The DCA showed that the prediction model was clinically useful within the whole threshold range.

CONCLUSION

Low BMD, leakage of bone cement and "O" shaped distribution of bone cement are independent risk factors for AVCF after vertebroplasty. The nomogram prediction model has good predictive ability and clinical benefit.

Systematic Retrospective Analysis of Risk Factors and Preventive Measures of Bone Cement Leakage in Percutaneous Kyphoplasty

OBJECTIVE

In this study, we aimed to analyze the risk factors of bone cement leakage in percutaneous kyphoplasty (PKP) treatment of osteoporotic vertebral compression fractures (OVCFs), and provide suggestions for reducing bone cement leakage.

METHODS

A retrospective study of 517 cases of OVCFs treated with PKP were divided into 2 groups according to whether they had bone cement leakage or not, leakage group (n = 72) and non-leakage group (n = 445). The risk factors of leakage were systematically analyzed using clinical baseline data, imaging observation data, and surgery-related factors. To select the statistically significant results (P < 0.05) among the risk factors mentioned above, we used the binary logistic regression method to identify the main risk factors.

RESULTS

The univariate analysis of clinical baseline data，imaging observation data, and surgery-related factors showed that bone mineral density (BMD) (P < 0.001), hypertension (P < 0.05), injury factors (P < 0.01), cortical defect (P < 0.001), grade of vertebral compression (P < 0.001), surgical approach (P < 0.05), stage of bone cement injection (P < 0.01), and balloon pressure (P < 0.05) were the risk factors for bone cement leakage. The recovery rate of vertebral height, and the Cobb angle correction rate were lower in the bone cement leakage group (P < 0.001). The correction effect of kyphosis after operation was limited. Binary logistic analysis results showed that BMD (odds ratio [OR] 5.605), cortical defect (OR 3.115), and stage of bone cement injection (OR 2.385) were bone cement leakage-independent risk factors.

CONCLUSIONS

Impairment of BMD value, defects of cortical bone, and inappropriate stage of bone cement injection will increase the risk of bone cement leakage in PKP treatment and limit PKP effects.

Incidence, Risk Factors, and Outcomes of Symptomatic Bone Cement Displacement following Percutaneous Kyphoplasty for Osteoporotic Vertebral Compression Fracture: A Single Center Study

STUDY DESIGN

Retrospective.

BACKGROUND

Symptomatic bone cement displacement (BCD) is a rare complication following percutaneous kyphoplasty (PKP) interventions for osteoporotic vertebral compression fracture (OVCF). This study aimed to investigate the incidence and the outcomes of symptomatic BCD comprehensively and identify its risk factors.

METHODS

The clinical data of patients treated with PKP for OVCF between January 2012 and December 2020 were extracted. Patients who developed BCD following PKP during follow-up were divided into the symptomatic and asymptomatic groups. Patients who did not develop BCD were assigned to the control group. Univariate and multiple logistic regression analyses were used to compare the three clinical groups' features to assess the independent risk factors for the symptomatic and asymptomatic groups.

RESULTS

A total of 896 patients were enrolled. Twenty-one patients (2.3%) were identified as having symptomatic BCD following PKP for OVCF, and 35 (3.9%) developed asymptomatic BCD. Compared with the control group, the symptomatic and asymptomatic groups had a higher incidence of anterior leakage, intravertebral vacuum cleft (IVC) signs, and a lower cement distribution score. The symptomatic group had a lower relative cross-sectional area (rCSA) of the paraspinal muscle (PSM), higher PSM fatty degeneration, and higher kyphotic angle (at the last follow-up) than the asymptomatic and control groups. For outcomes, the symptomatic group had a higher VAS/ODI score and a higher incidence of new vertebral fractures compared with the asymptomatic and control groups. Anterior leakage (OR: 1.737, 95% CI: 1.215-3.300), the IVC sign (OR: 3.361, 95% CI: 1.605-13.036), the cement distribution score (OR: 0.476, 95% CI: 0.225-0.904), PSM rCSA (OR: 0.953, 95% CI: 0.917-0.992), and PSM fatty degeneration (OR: 1.061, 95% CI: 1.005-1.119) were identified as independent risk factors for the symptomatic group. Anterior leakage (OR: 1.839, 95% CI: 1.206-2.803), the IVC sign (OR: 2.936, 95% CI: 1.174-9.018), and cement distribution score (OR: 0.632, 95% CI: 0.295-0.858) were independent risk factors for the asymptomatic group.

CONCLUSION

The incidence of symptomatic BCD is 2.3% in patients treated with PKP. Anterior leakage, the IVC sign, and the distribution score were independent risk factors for BCD, and paraspinal muscle degeneration was a specific risk factor for symptomatic BCD. Symptomatic BCD can lead to poor outcomes.

A predictive nomogram for intradiscal cement leakage in percutaneous kyphoplasty for osteoporotic vertebral compression fractures combined with intravertebral cleft

BACKGROUND

For patients with osteoporotic vertebral compression fractures (OVCFs) treated with percutaneous kyphoplasty (PKP), the occurrence and risk factors of intradiscal cement leakage should be characteristic of the presence of intravertebral cleft (IVC). This study aimed to identify risk factors for intradiscal leakage in individuals with OVCFs combined with IVC treated with PKP and build a powered and well-calibrated predictive nomogram.

METHODS

This study retrospectively reviewed consecutive patients who underwent PKP at our center between January 2016 and May 2021. Patients diagnosed with OVCFs combined with IVC were identified, and the incidence of different types of bone cement leakage was recorded. Risk factors for intradiscal leakage among the demographic, perioperative baseline, and radiologic data were identified, following which a nomogram was developed and verified.

RESULTS

A total of 109 eligible patients were included, and the intradiscal leakage rate was 32.1%. Compression rate (odds ratio [OR] 0.025; 95% confidence interval [CI] 0.002-0.264; P = 0.002) and cemented vertebral body fraction (OR 44.122; 95% CI 2.790-697.740; P = 0.007) were identified as independent risk factors. A predictive nomogram with good predictive power (C-statistic = 0.786) and fitness of data (Hosmer-Lemeshow goodness-of-fit test, P = 0.092) was established to build a quantitative relationship between the risk factors and intradiscal leakage.

CONCLUSION

The incidence rate of intradiscal leakage in PKP for OVCFs combined with IVC was 32.1%. Compression rate and cemented vertebral body fraction were identified as independent risk factors. A powered and well-calibrated nomogram was established to accurately predict the probability of intradiscal leakage. Further prospective and multicenter studies are required to verify and calibrate our findings.

Cement leakage in percutaneous vertebroplasty for spinal metastases: a retrospective study of risk factors and clinical outcomes

Objective

The objective of this research was to investigate the risk factors of cement leakage in patients with metastatic spine tumors following percutaneous vertebroplasty (PVP).

Methods

Sixty-four patients with 113 vertebrae were retrospectively reviewed. Various clinical indexes, including age, sex, body mass index (BMI), smoking history, drinking history, chemotherapy history, radiotherapy history, primary cancer, location, other metastases, collapse, posterior wall defects, the laterality of injection, and the injected cement volume were analyzed as potential risk factors. Multivariate analyses were conducted to identify the independent risk factors.

Results

The cement leakage was found 64 in 113 treated vertebrae (56.63%), in which the incidence of each type was shown as below: spinal canal leakage 18 (15.93%), intravascular leakage around the vertebrae 11 (9.73%), and intradiscal and paravertebral leakage 35 (30.97%). Tomita classification (P = 0.019) and posterior wall destruction (P = 0.001) were considered strong risk factors for predicting cement leakage in general. The multivariate logistic analysis showed that defects of the posterior wall (P = 0.001) and injected volume (P = 0.038) were independently related to the presence of spinal canal leakage. The postoperative visual analog scale (VAS) and activities of daily living (ADL) scores showed significant differences compared with the pre-operative parameters (P < 0.05). No significant differences were found in every follow-up time between the leakage group and the non-leakage group for pain management and improvement of activities in daily life.

Conclusion

In our study, Tomita classification and the destruction of the posterior wall were independent risk factors for leakage in general. The defects of the posterior wall and injected volume were independently related to the presence of spinal canal leakage. The PVP procedure can be an effective way to manage the pain.

Comparison of the Effect of Different Local Analgesia Administration Methods in Percutaneous Vertebroplasty: A Retrospective Cohort Study

Objective

Although various studies have described the methods of administering anesthesia during percutaneous vertebroplasty (PV) for treating osteoporotic vertebral compression fractures (OVCFs), there is still no consensus on the optimal treatment regimen. Therefore, this study aimed to investigate the effects of three application methods of local analgesia administration in PV for treating OVCFs.

Methods

A total of 96 patients with OVCFs were reviewed and divided into three groups (A: lidocaine, B: ropivacaine, C: lidocaine + ropivacaine). The visual analog scale (VAS), blood pressure (BP), heart rate (HR), blood oxygen saturation (BOS), and surgery time were recorded during the following different points: before puncture, during the puncture, cement injection, and 4-h after surgery.

Results

The mean age of the patients was 74.13 ± 7.02 years in group A, 70.47 ± 5.50 years in group B, and 73.07 ± 7.51 years in group C, without significant difference. No significant differences were found in sex, age, hospital stay, surgery time, blood loss, and cement volume of the patients. In the periods of before puncture and 4-h after surgery, the VAS in group C decreased significantly than that in the periods of the puncture, cement injection, and immediately after surgery. Overall, there were no significant differences in systolic BP, diastolic BP, HR, and BOS during the different periods among the groups except HR in the period of the puncture in group C, which was slower than that in other groups, and HR in the period of cement injection in group A, which was faster than the other two groups. A correlation was observed between the VAS and the periods of cement injection (r = 0.5358) and after surgery (r = 0.5775) in group C.

Conclusion

Compared with the other two methods, the use of lidocaine in combination with ropivacaine could effectively relieve intraoperative pain, making the patients feel more comfortable and experience better recovery.

Risk factors for predicting cement leakage in percutaneous vertebroplasty for spinal metastases

BACKGROUND

The study aimed to identify the risk factors of cement leakage following percutaneous vertebroplasty for spinal metastases.

METHODS

230 consecutive patients with 530 vertebrae were retrospectively reviewed. Characteristics including age, primary cancer, location, pathological fracture, the integrity of the posterior wall, and the volume of bone cement were considered as potential risk factors. Cement leakage was evaluated by postoperative imaging examination and classified into three subtypes with different potential sequelae: spinal canal leakage, intravascular leakage around vertebrae, intradiscal and paravertebral leakage. Univariate and multivariate analyses were used to assess the risk factors.

RESULTS

Leakage was detected in 185 vertebrae (34.9%), 18.3% for intradiscal and paravertebral, 13.2% for intravascular around vertebrae, and 7.0% for spinal canal. Multivariate analysis showed that incomplete posterior wall (P = 0.001) and breast cancer (P = 0.015) were strong predictive factors for spinal canal leakage, incomplete posterior wall (P = 0.024) was for intravascular leakage around vertebrae, thoracic (P = 0.010) and pathological fracture (P = 0.000) were for intradiscal and paravertebral leakage.

CONCLUSIONS

Our findings suggest that cement leakage is common following percutaneous vertebroplasty for spinal metastases. The incomplete posterior wall is an unfavourable factor for intravascular leakage around vertebrae. Vertebrae with incomplete posterior wall and breast cancer metastases are more likely to develop spinal canal leakage.

A Nomogram to Predict Intra-Spinal Canal Cement Leakage Among Elderly Patients with Spine Metastases: An Internal-Validated Model

Purpose

This study aimed to assess the risk variables for predicting intra-spinal canal cement leakage, especially among elderly patients with spine metastases after being treated with percutaneous vertebroplasty (PVP). Furthermore, we proposed and validated a nomogram to stratify risks of intra-spinal canal cement leakage.

Methods

We retrospectively analyzed 163 elderly patients (age ≧65 years) with spine metastases who underwent PVP. Patients were randomly divided into a training cohort (n=100) and a validation cohort (n=63). The multivariate logistic regression analysis was used to screen potential risk variables in the training cohort. Significant risk variables were included in the nomogram, and the nomogram was developed according to the estimates of the each included variable. The predictive effectiveness of the nomogram was validated using discrimination and calibration performance.

Results

The overall prevalence of intra-spinal canal cement leakage was 9.82% (16/163). In the training cohort, female patients (14.71%, 5/34) showed a higher rate of intra-spinal canal cement leakage as compared with male patients (4.55%, 3/66). The nomogram consisted of sex, cortical osteolytic destruction in posterior wall, and load-bearing lines of spine. The nomogram had acceptable discrimination, with the area under the receiver operating characteristic (AUROC) of 0.75 in the training cohort, 0.64 in the validation cohort, and 0.69 in the entire cohort, and also showed favorable calibration based on the goodness-of-fit test. According to the nomogram, three risk groups were developed: the low risk group had an actual probability of 7.03%, the medium risk group was 11.54%, and high risk group was 44.44%. The difference between the three groups was significant (P ˂ 0.01).

Conclusion

Intra-spinal canal cement leakage after PVP is not scarce among elderly patients. We proposed and internally validated a nomogram that is capable of calculating the risk of intra-spinal canal cement leakage among elderly patients with spine metastases. Careful surgical plan should be conducted among patients with a high risk of developing intra-spinal canal cement leakage.

The impact of intravertebral cleft on cement leakage in percutaneous vertebroplasty for osteoporotic vertebral compression fractures: a case-control study

Background

The impact of intravertebral cleft (IVC) on cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs) has been discussed. However, the results were conflicting, as the study population and cement leakage classification were heterogeneous. The aim of the study was to evaluate the impact of IVC on the incidence of leakage through vein, leakage through cortex as well as general leakage in PVP for OVCFs.

Methods

All patients with OVCFs who underwent PVP between January 2016 and June 2019 at our institution were retrospectively reviewed. Patients were eligible for this case-control study if they were diagnosed as single level fracture in spine. After inclusive and exclusive criteria were met, a total of 139 patients with IVC were enrolled as the study group. Non-IVC controls were matched in a 1:1 ratio in age (within 3 years), sex and fracture severity with patients in study group. Cement leakage were classified into four types [type B (through basivertebral vein), type S (through segmental vein), type-C (through a cortical defect), and type D (intradiscal leakage)], furtherly into two types [venous type (type-B or/and type S) and cortical type (type-C or/and type-D)]. A general leakage rate and a specific leakage rate per each type were compared between both groups.

Results

Each group included 139 patients. Groups were homogenous for age, sex, fracture severity, fracture location, fracture type, cement volume, puncture approach and property of cement. Compared with control group, IVC group had a significantly lower rate of type-B (20.9% vs. 31.7%, P = 0.041), type-S (24.5% vs. 52.5%, P = 0.000), and venous type leakage (37.4% vs. 67.6%, P = 0.000), a significantly higher rate of type-C (25.9% vs. 12.2%, P = 0.004), type-D (16.5% vs. 6.5%, P = 0.009), and cortical type leakage (40.3% vs. 16.5%, P = 0.000), no significant difference on the rate of general leakage (67.6% vs. 76.3%, P = 0.109).

Conclusion

IVC decreased the risk of cement leakage through vein and increased the risk of cement leakage through cortex. However, it had no significant effect on the occurrence of general leakage.

Comparison of Cement Leakage Rate and Severity After Percutaneous Vertebroplasty for Osteoporotic Vertebral Compression Fractures Using Front-Opening Versus Side-Opening Cannulas

The authors assessed the occurrence and severity of cement leakage (CL) following percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs) performed using front-opening cannulas (FOCs) vs side-opening cannulas (SOCs). This retrospective cohort study included 811 patients with single-level OVCFs who underwent PVP between March 2016 and September 2018. The 264 patients who met the inclusion criteria were divided into two groups according to whether the procedure was performed using a FOC (n=128) or a SOC (n=136). Visual analog scale score, Oswestry Disability Index, local kyphotic angle, vertebral height, amount of bone cement injected, and rate of CL were compared between the groups. Types of CL were classified according to postoperative computed tomography. The CL types were further classified according to severity (mild and severe). Visual analog scale score, Oswestry Disability Index, local kyphotic angle, and vertebral height were all significantly improved after surgery. The total incidence of CL was significantly higher for FOCs than for SOCs (P=.001). Similarly, the occurrence of the CL subtypes was significantly higher for FOCs than for SOCs (B type, P=.033; C type, P=.01; and S type, P=.015). Analysis of CL type severity revealed that the rates of severe D type (intradiskal leakage category of the C type) and severe S type were significantly lower for SOCs than for FOCs (P=.001), while the incidence of severe B type leaks was not significantly different between the groups (P=.443). Percutaneous vertebroplasty performed using SOCs decreases the incidence and severity of D type and S type CL compared with FOCs. Secondary classification of CL could help physicians better understand the severity of leakage and select a more appropriate surgical approach to reduce CL. [Orthopedics. 2021;44(3):134-140.].

An independent inter- and intra-observer agreement assessment of Yeom classification for bone cement leakage following vertebroplasty/kyphoplasty

STUDY DESIGN

An inter- and intra-observer agreement study.

BACKGROUND

In recent years, vertebroplasty and kyphoplasty have been widely used in treating osteoporotic vertebral compression fractures (OVCF) though the clinical efficacy of them is still controversial. However, there are also inevitable complications, first and foremost is bone cement leakage (BCL). Yeom classification is commonly used to evaluate BCL. The objective of this study is to assess its reliability and reproducibility, and to explore its clinical application value.

METHODS

All 58 patients with BCL following vertebroplasty/kyphoplasty were involved. Six spine surgeons were selected to be evaluators as they were unaware of the identity of the patients and the treatment they received. They classified BCL according to Yeom system, we used kappa (K) to assess the inter- and intra-observer agreement. After 12 weeks, we repeated the analysis.

RESULTS

The inter-observer reliability of Yeom classification was substantial with K value of 0.71 (1st assessment) and 0.73 (2nd assessment). The intra-observer reproducibility of Yeom classification was near perfect with K value of 0.88.

CONCLUSION

Yeom classification system has substantial inter-observer reliability and near perfect intra-observer reproducibility in BCL following vertebroplasty/kyphoplasty, which can be widely used in clinical care as an appropriate instrument for early observation, mechanism and severity cognition, and prognosis predicting of BCL. Besides, the adding of type M (the mixed type) may improve the classification.

Epidemiology and detection of cement leakage in patients with spine metastases treated with percutaneous vertebroplasty: A 10-year observational study

•

Cement leak is common for percutaneous vertebroplasty in metastatic spinal disease.

•

A proposed and validated algorithm can screen patients with high cement leak risk.

•

The algorithm included four significant characteristics.

•

The validation group AUROC was 0.69, and the goodness-of-fit test P-value was 0.50.

Objectives

To investigate the epidemiology of cement leaks and further develop an algorithm to detect the high risk of cement leaks among advanced cancer patients with metastatic spinal disease treated with percutaneous vertebroplasty.

Methods

This study retrospectively analyzed 309 patients with metastatic spinal disease treated with percutaneous vertebroplasty. Patients were randomly divided into a training group and a validation group. In the training group, 13 potential characteristics were analyzed for their abilities to predict cement leaks. Discal cement leakage and paravertebral cement leakage were excluded from the analysis. Those characteristics identified as having significant predictive value were used to develop a predictive algorithm. Internal validation of the algorithm was performed based on discrimination and calibration qualities.

Results

Overall, cement leaks occurred in 61.17% (189/309) patients. Among the 13 characteristics analyzed, younger age (P = 0.03), extravertebral bone metastases (P = 0.02), increased number of treated vertebrae levels (P < 0.01), and cortical osteolytic destruction in the posterior wall (P = 0.01) were included in the algorithm. This algorithm generates a score between 0 and 16 points, with higher scores indicating a higher risk of cement leakage. The area under the receiver operating characteristic curve (AUROC) value for the algorithm was 0.75 in the training group and 0.69 in the validation group. The mean correct classification rates for the training and validation groups were 73.5% and 64.9%, respectively, and the corresponding P-values of the goodness-of-fit test were 0.70 and 0.50.

Conclusions

Cement leaks are common in patients with metastatic spinal disease treated with percutaneous vertebroplasty. The present study proposed and internally validated an algorithm that can be used to screen patients at high risk of cement leakage.

Navigation-guided percutaneous pelvic cementoplasty for metastatic bone pain: A case report

RATIONALE

Percutaneous cementoplasty is a minimally invasive procedure that can provide immediate pain relief and improve range of motion in patients with metastatic bone pain. Conventionally, this procedure is guided by computed tomography (CT). However, to minimize exposure to radiation, we performed percutaneous cementoplasty under the guidance of a navigation system.

PATIENT CONCERNS

A 60-year-old man presented with left hip pain for several months due to bone metastasis in the left ilium.

DIAGNOSES

The patient was diagnosed with lung cancer and multiple bone metastases including ileum.

INTERVENTIONS

The puncture needle was placed under the guidance of a navigation system with pre-procedure CT images, and bone cement was injected into the osteolytic lesion in the left ilium.

OUTCOMES

Bone cement placement was confirmed by post-procedure radiography, and its distribution was satisfactory. The patient's Karnofsky Performance Scale and Brief Pain Inventory scores showed improvement in pain and mobility without complications.

LESSONS

Percutaneous cementoplasty guided by a navigation system is a safer and more effective method with less radiation compared with conventional CT-guided methods.

Selections of Bone Cement Viscosity and Volume in Percutaneous Vertebroplasty: A Retrospective Cohort Study

OBJECTIVE

We sought to evaluate the efficacy and complications of percutaneous vertebroplasty with different viscosities and volumes of bone cement in treating osteoporotic vertebral compression fractures (OVCFs).

METHOD

We conducted a retrospective cohort study of 307 patients treated for a single thoracolumbar level (T12-L2) OVCF in our hospital between January 2014 and December 2019. The patients were divided into 6 groups according to different viscosities (I: low-viscosity bone cement, II: high-viscosity bone cement) and injection volumes (A, 2-4 mL; B, 4-6 mL; C, 6-8 mL) of bone cement. Clinical and radiologic characteristics including visual analog scale, local kyphotic angle, anterior vertebral height ratio, cement leakage, and vertebral body recollapse rate were collected preoperatively, 2 days postoperation, and at the last follow-up to assess the efficacy and complications of each group.

RESULTS

Regarding efficacy, there was no significant difference between the 2 kinds of bone cement. Injecting >4 mL of cement can provide patients with good improvements of clinical indicators and a low vertebral body recollapse rate. Injecting 6-8 mL of bone cement slightly improved the radiologic indicators. However, the leakage rate of low-viscosity bone cement increased significantly when the volume exceeded 6 mL. The leakage rate of high-viscosity bone cement did not increase significantly at the volume of 6-8 mL.

CONCLUSIONS

In summary, when treating single thoracolumbar level OVCFs, the recommended volume of low-viscosity bone cement is 4-6 mL while the optimal volume of high-viscosity bone cement is 6-8 mL.

Risk factors of postoperative bone cement leakage on osteoporotic vertebral compression fracture: a retrospective study

Purpose

To investigate risk factors of bone cement leakage in percutaneous vertebroplasty(PVP)for osteoporotic vertebral compression fracture (OVCF).

Methods

A total of 236 patients (344 vertebrae) who underwent PVP between November 2016 and June 2020 were enrolled in the study. Clinical and radiological characteristics, including age, gender, course of disease, trauma, type of vertebral fracture, cortical continuity of vertebral body, intervertebral vacuum cleft (IVC), fracture severity, fracture level, basivertebral foramen, bone cement dispersion types, the cement injection volume, the type of cement leakage, puncture approach, and intrusion of the posterior wall, were considered as potential risk factors. Three types of leakage (type-B, type-C, and type-S) were defined and risk factors for each type were analyzed. Logistic analysis was used to study the relationship between each factor and the type of cement leakage.

Results

The incidences of the three types of leakage were 28.5%, 24.4%, and 34.3%. The multinomial logistic analysis revealed that the factors of type-B leakage were the shape of cement and basivertebral foramen. One significant factor related to type-C leakage was cortical disruption, and the factors of type-S leakage were bone cement dispersion types, basivertebral foramen, cleft, fracture severity, an intrusion of the posterior wall, and gender.

Conclusion

Different types of cement leakage have their own risk factors, and the analysis of risk factors of these might be helpful in reducing the rate of cement leakage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02337-1.

Basivertebral foramina of true vertebrae: morphometry, topography and clinical considerations

PURPOSE

Basivertebral foramina (BVF) are openings of the posterior wall of vertebral body (VB) that lead to basivertebral canals (BVC), where homonymous neurovascular bundle courses. BVF and BVC are implicated with spinal fractures, vertebral augmentation and basivertebral nerve radiofrequency ablation. Despite their essential clinical impact, knowledge of BVF precise anatomy is scarce. The current study describes in detail the BVF typical morphological and topographical anatomy, morphometry and variants.

METHODS

In total, 1561 dried true vertebrae of 70 Greek spines of known gender and age were examined. BVF number, location, shape and size (in foramina > 1 mm), BVF distance from VB rims and pedicles, as well as VB morphometry (diameters, heights and distance between pedicles) were studied. Ten spines were re-examined by computed tomography and BVC depth and shape were recorded. Correlations and differences were statistically analyzed.

RESULTS

C₁ lack BVF (3.4%). One BVF was found in 45.1%, two in 36.9%, three in 3.8% and four BVF in 0.6%. Multiple small (< 1 mm) foramina were observed in 10.1%. Asymmetry was detected in 12.3%. C₂ and T₁₀-L₁ presented typical pattern, whereas C₃ and T₂ had the greatest variability. BVF were significantly closer to the upper rim in C₂ and T₁₀-L₄ and to the lower rim in C₇-T₄, T₆-T₈ and L₅. The mean BVC depth was 12-21.8% of the VB anteroposterior diameter.

CONCLUSION

BVF number, shape, size and topography are described, in detail, per vertebral level. The provided morphological classification and the created cumulative BVF topographic graphs should assist in clinical practice and surgery.

Risk Factors for Cement Leakage in Percutaneous Vertebroplasty for Osteoporotic Vertebral Compression Fractures: An Analysis of 1456 Vertebrae Augmented by Low-Viscosity Bone Cement

STUDY DESIGN

Retrospective study.

OBJECTIVE

To identify risk factors for cement leakage in percutaneous vertebroplasty (PVP) using low-viscosity bone cement for osteoporotic vertebral compression fractures (OVCFs).

SUMMARY OF BACKGROUND DATA

Cement leakage is the most common complication for PVP and its risk factors have been discussed. However, data in previous series were heterogeneous. Additionally, relative smaller patient sample or more types of cement leakage classified in those studies made the results conflicting.

METHODS

A total of 1090 patients who underwent PVP with low-viscosity bone cement for OVCFs in 1456 levels between January 2016 and June 2019 were retrospectively reviewed. Parameters potentially affecting the occurrence of cement leakage were assessed using univariate and multivariate analyses. Cement leakage was assessed using postoperative computed tomography scanning, and classified into two types (cortical leakage and venous leakage) considering the mechanism.

RESULTS

The incidence of cortical and venous leakage were 20.3% (295/1456) and 56.2% (819/1456), respectively. Cortical disruption, basivertebral foramen were the strongest risk factors for cortical leakage (P = 0.000), venous leakage (P = 0.000), respectively. Greater cement volume is one risk factor for both cortical leakage and venous leakage. The intravertebral cleft, solid type of cement distribution were significant risk factors for cortical leakage, and they both were protective factors for venous leakage. For cortical leakage, older age and trauma were another two risk factors. For venous leakage, female was another one risk factor, and higher grade of fracture severity is the strongest protective factor.

CONCLUSION

Both cortical leakage and venous leakage are prevalent. Adequate known of risk factors could help balance the incidence of two type leakage in unique vertebra and reduce the incidence of leakage in general in PVP for OVCFs.Level of Evidence: 3.

Short-term Efficacy of the Percutaneous Vertebroplasty Using a Curved Versus Straight Vertebroplasty Needle in Osteoporotic Vertebral Compression Fractures

The purpose of this study was to compare the efficacy of the curved puncture approach with 2 conventional approaches in percutaneous vertebroplasty (PVP) for the treatment of single-level osteoporotic vertebral compression fractures. Ninety-six patients with a single-level thoracolumbar vertebral fracture were surgically treated in the authors' department from February 2016 to February 2018. Patients were randomly divided into 3 groups, including 25 patients who had PVP punctured with a curved vertebroplasty needle (group C), 40 patients with unipedicular PVP with a straight vertebroplasty needle (group U), and 31 patients with bipedicular PVP with a straight vertebroplasty needle (group B). The short-term efficacies of PVP using different vertebroplasty needles were compared. Significant differences were tested preoperatively and postoperatively in vertebral body height variation, visual analog scale score, and Oswestry Disability Index in each of the 3 groups (P<.05). There was no significant difference among the groups in terms of Cobb angle correction and bone cement leakage. Group C and group U were superior to group B in terms of operative time and injected cement volume (P<.05). Twenty-four (96.0%) patients in group C and 29 (93.5%) patients in group B had centered cement distribution without significant differences (P>.05), which was superior to group U (P<.05). Curved puncture PVP achieved a satisfactory clinical outcome for osteoporotic vertebral compression fractures, with the advantages of less operative time, less injected cement volume, and more reasonable cement distribution for stabilization of the affected vertebrae. [Orthopedics. 2021;44(1):e131-e138.].

Risk factors for cement leakage and nomogram for predicting the intradiscal cement leakage after the vertebra augmented surgery

Background

Vertebral augmentation is the first-line treatment for the osteoporosis vertebral compression fractures. Bone cement leakage is the most common complication of this surgery. This study aims to assess the risk factors for different types of cement leakage and provides a nomogram for predicting the cement intradiscal leakage.

Methods

We retrospectively reviewed 268 patients who underwent vertebral augmentation procedure between January 2015 and March 2019. The cement leakage risk factors were evaluated by univariate analysis. Different types of cement leakage risk factors were identified by the stepwise logistic analysis. We provided a nomogram for predicting the cement intradiscal leakage and used the concordance index to assess the prediction ability.

Results

A total of 295 levels of vertebrae were included, with a leakage rate of 32.5%. Univariate analysis showed delayed surgery and lower vertebral compression ratio were the independent risk factors of cement leakage. The stepwise logistic analysis revealed percutaneous vertebroplasty was a risk factor in vein cement leakage; delayed surgery, preoperative compression ratio, and upper endplate disruption were in intradiscal cement leakage; age, preoperative fracture severity, and intravertebral vacuum cleft were in perivertebral soft tissue cement leakage; no factor was in spinal canal cement leakage. The nomogram for intradiscal cement leakage had a precise prediction ability with an original concordance index of 0.75.

Conclusions

Delayed surgery and more vertebral compression increase the risk of cement leakage. Different types of cement leakage have different risk factors. We provided a nomogram for precise predicting the intradiscal cement leakage.

Transforaminal Interbody Impaction of Bone Graft to Treat Collapsed Nonhealed Vertebral Fractures with Endplate Destruction: A Report of Two Cases

Background

A collapsed nonhealed vertebral fracture with endplate destruction is a challenging injury to address, as there is no single definitive treatment. We present two cases using an innovative transforaminal grafting technique to treat these patients. Case Presentation. Case 1: a 72-year-old woman had nonunion of an L1 compression fracture with destruction of both endplates. T12/L1 and L1/L2 transforaminal debridement and impaction of bone graft were performed followed by posterior instrumentation. At three years follow-up, the fusion mass between T12/L1 and L1/L2 was solid and the patient had minimal pain. Case 2: a 62-year-old woman had nonunion of an L1 burst fracture with destruction of the lower endplate. Hemilaminectomy and transforaminal interbody impaction of bone graft was performed. At three years follow-up, the patient had no back pain and a solid fusion. In both cases, local kyphosis was corrected and fusion obtained.

Conclusions

Collapsed nonhealed vertebral body fractures combined with endplate destruction can be successfully treated with a one-step posterior surgery consisting of transforaminal debridement and impaction of bone graft in combination with posterior pedicle instrumentation.

[Effectiveness comparison of low-temperature bone cement perfusion before and after improvement in percutaneous vertebroplasty]

OBJECTIVE

To discuss the safety and effectiveness of the improved technique by comparing the effects of low temperature bone cement infusion before and after the improvement in the percutaneous vertebroplasty (PVP).

METHODS

The clinical data of 170 patients (184 vertebrae) with osteoporotic vertebral compression fracture who met the selection criteria between January 2016 and January 2018 were retrospectively analyzed. All patients were treated with PVP by low-temperature bone cement perfusion technology. According to the technical improvement or not, the patients were divided into two groups: the group before the technical improvement (group A, 95 cases) and the group after the technical improvement (group B, 75 cases). In group A, the patients were treated by keeping the temperature of bone cement at 0℃ and parallel puncture; in group B, the patients were treated by increasing the temperature of bone cement or reducing the time of bone cement in ice salt water and cross puncture. There was no significant difference in gender, age, disease duration, T value of bone mineral density, operative segment, and preoperative vertebral compression rate, visual analogue scale (VAS) score between the two groups ( P>0.05). CT examination was performed immediately after operation, and the leakage rate of bone cement was calculated. The amount of bone cement perfusion and the proportion of bone cement in contact with the upper and lower endplates at the same time were compared between the two groups. The vertebral compression rate was calculated and the VAS score was used to evaluate the pain before operation, at immediate after operation, and last follow-up.

RESULTS

There was no complication such as incision infection, spinal nerve injury, or pulmonary embolism in both groups. There was no significant difference in the amount of bone cement perfusion between groups A and B ( t=0.175, P=0.861). There were 38 vertebral bodies (36.89%) in group A and 49 vertebral bodies (60.49%) in group B exposed to bone cement contacting with the upper and lower endplates at the same time, showing significant difference ( χ 2=10.132, P=0.001). Bone cement leakage occurred in 19 vertebral bodies (18.45%) in group A and 6 vertebral bodies (7.41%) in group B, also showing significant difference ( χ 2=4.706, P=0.030). The patients in group A and group B were followed up (13.3±1.2) months and (11.5±1.1) months, respectively. The vertebral compression rates of the two groups at immediate after operation were significantly lower than those before operation ( P<0.05), but the vertebral compression rate of group A at last follow-up was significantly higher than that at immediate after operation ( P<0.05), and there was no significant difference in group B between at immediate after operation and at last follow-up ( P>0.05). The VAS scores of the two groups at immediate after operation were significantly lower than those before operation ( P<0.05); but the VAS scores of group A at last follow-up were significantly higher than those at immediate after operation ( P<0.05) and there was no siginificant difference in group B ( P>0.05). There was no significant difference in VAS scores between the two groups at immediate after operation ( t=0.380, P=0.705); but at last follow-up, VAS score in group B was significantly lower than that in group A ( t=3.627, P=0.000).

CONCLUSION

The improved advanced low-temperature bone cement perfusion technology during PVP by increasing the viscosity of bone cement combined with cross-puncture technology, can reduce bone cement leakage, improve the distribution of bone cement in the vertebral body, and reduce the risk of vertebral collapse, and achieve better effectiveness.

Cement leakage following percutaneous kyphoplasty in a patient after a posterior lumbar fusion: a case report

BACKGROUND

Percutaneous kyphoplasty (PKP) has become an important minimally invasive surgical technique for fracture stabilization and pain relief in patients with vertebral compression fractures. However, intraspinal cement leakage following PKP is a serious postoperative complication that can lead to morbidity and mortality.

CASE PRESENTATION

We describe an uncommon case of epidural leakage of bone cement in an 81-year-old woman who underwent posterior lumbar decompression and fusion from L3-5 4 years prior and had an unremarkable postoperative course. The patient was admitted to Peking Union Medical College Hospital with complaints of muscle weakness and severe low back pain radiating to the left thigh 1 week after PKP of L5 due to an acute osteoporotic compression fracture. Computed tomographic imaging revealed massive leakage of cement into the spinal canal at L5-S1, and therefore, surgical decompression and removal of epidural cement were performed carefully without causing a dural tear. She improved remarkably and no neurologic deterioration was observed in the postoperative period during the one-year follow-up.

CONCLUSIONS

We present the rare reported case, to our knowledge, of epidural cement leakage after PKP at the segment of internal fixation and discuss the most likely etiologies and preventive measures for this condition.

Vertebroplasty and vertebroplasty in combination with intermediate bilateral pedicle screw fixation for OF4 in osteoporotic vertebral compression fractures: a retrospective single-Centre cohort study

Background

Although various studies have described the outcomes and complications of each treatment for OF 4 in osteoporotic vertebral compression fractures (OVCFs), there is still no consensus on the optimal treatment regimen. This study aimed to investigate the clinical effect of OF 4 in patients with OVCFs treated with percutaneous vertebroplasty (PV) compared with PV in combination with intermediate bilateral pedicle screw fixation (IBPSF).

Methods

A total of 110 patients with OF 4 in OVCFs from January 2011 to December 2013 were reviewed retrospectively and divided into two groups (group A: PV, group B: PV + IBPSF). According to the guidelines of the German Society for Orthopaedics and Trauma (DGOU), OF 4 consists of 3 fracture types. The clinical and radiographic assessments were observed preoperatively, postoperatively, and during follow-up.

Results

The patients were followed for an average of 60.50 ± 15.20 months (group A) and 58.20 ± 17.60 months (group B) without significant differences. No significant differences were found in BMD, BMI and cement volume between the two groups, but differences were found for operation time, blood loss, and hospitalization time. The VAS and ODI scores improved better significantly at the final follow-up in group B but not in group A. Compared with the preoperative values, the postoperative kyphosis angle and loss of fractured segment height significantly improved, but the difference between the groups was significant after 3 months postoperatively. The loss of angular correction and fractured segment height in group A were greater than those in group B. A total of 15 cases of cement leakage were observed in group A and 8 cases in group B, and no complications or revision surgeries were observed in either group. Thirteen new fractures occurred (11 in group A and 2 in group B), which was significant.

Conclusion

PV with IBPSF could provide effective restoration and maintenance of fractured segment height and segment alignment as well as a lower rate of complications of OF 4 in OVCFs.

A mysterious risk factor for bone cement leakage into the spinal canal through the Batson vein during percutaneous kyphoplasty: a case control study

BACKGROUND

Percutaneous kyphoplasty (PKP) can effectively treat osteoporotic vertebral compression fractures (OVCFs). Although satisfactory clinical outcomes can be achieved, bone cement leakage remains a primary complication of PKP. Previous studies have found many high risk factors for bone cement leakage into the spinal canal; however, less attention to the posterior wall morphologies of different vertebral bodies may be one reason for the leakage. Here, we investigated the effect of posterior vertebral wall morphology in OVCF patients on bone cement leakage into the spinal canal during PKP.

METHODS

Ninety-eight OVCF patients with plain computed tomography (CT) scans and three-dimensional (3D) reconstruction images from T6 to L5 were enrolled. 3D-CT and multiplanar reconstructions (MPR) were used to measure the concave posterior vertebral wall depth (PVWCD) and the corresponding midsagittal diameter of the nonfractured vertebral body (VBSD), and the PVWCD/VBSD ratio was calculated. All subjects were divided into the thoracic or lumbar groups based on the location of the measured vertebrae to observe the value and differences in the PVWCD between both groups. The differences in PVWCD and PVWCD/VBSD between the thoracic and lumbar groups were compared. Three hundred fifty-seven patients (548 vertebrae) who underwent PKP within the same period were also divided into the thoracic and lumbar groups. The maximal sagittal diameter (BCSD), the area of the bone cement intrusion into the spinal canal (BCA), and the spinal canal encroachment rate (BCA/SCA × 100%) were measured to investigate the effect of the thoracic and lumbar posterior vertebral wall morphologies on bone cement leakage into the spinal canal through the Batson vein during PKP.

RESULTS

The PVWCDs gradually deepened from T6 to T12 (mean, 4.6 mm); however, the values gradually became shallower from L1 to L5 (mean, 0.6 mm). The PVWCD/VBSD ratio was approximately 16% from T6 to T12 and significantly less at 3% from L1 to L5 (P < 0.05). The rate of bone cement leakage into the spinal canal through the Batson vein was 10.1% in the thoracic group and 3.7% in the lumbar group during PKP. In the thoracic group, the BCSD was 3.1 ± 0.5 mm, the BCA was 30.2 ± 3.8 mm², and the BCA/SCA ratio was 17.2 ± 2.0%. In the lumbar group, the BCSD was 1.4 ± 0.3 mm, the BCA was 14.8 ± 2.2 mm², and the BCA/SCA ratio was 7.4 ± 1.0%. The BCSD, BCA and BCA/SCA ratio were significantly higher in the thoracic group than in the lumbar group (P < 0.05).

CONCLUSIONS

The PVWCD in the middle and lower thoracic vertebrae can help reduce bone cement leakage into the spinal canal by enabling avoiding bone cement distribution over the posterior 1/6 of the vertebral body during PKP. The effect of the difference between the thoracic and lumbar posterior vertebral wall morphology on bone cement leakage into the spinal canal through the Batson vein in OVCF patients during PKP is one reason that the rate of bone cement leakage into the thoracic spinal canal is significantly higher than that into the lumbar spinal canal.

The cement leakage in cement-augmented pedicle screw instrumentation in degenerative lumbosacral diseases: a retrospective analysis of 202 cases and 950 augmented pedicle screws

PURPOSE

To evaluate the incidence, type and risk factors of cement leakage (CL) with cement-augmented pedicle screw instrumentation (CAPSI) in degenerative lumbosacral disease.

METHODS

Two hundred and two patients using a total of 950 cement-augmented screws were enrolled. CL was classified into three types: type S: leakage via segmental veins; type B: leakage via basivertebral veins; and type I: leakage via pedicle screw instrumentation to paravertebral soft tissue. The age, gender, operation stage (primary or later stage), body mass index, bone mineral density, the number and type of augmented screw, the position of the tip of screw (lateral or internal part of vertebral body), the position of screw (left or right side), the volume of bone cement, location of the augmented vertebra (lumbar or sacrum), the type of CL and complications were recorded. Binary logistic regression correlation was used to analyze risk factors of veins leakage (type S and type B).

RESULTS

The CL was observed in 165 patients (81.68%) and 335 screws (35.26%), leakage types of S, B and I were seen in 255 (76.12%), 77 (22.99%), and 30 (8.96%) of screws, respectively. Besides, double or multiple routes of leakage were seen in 27 screws. Number of augmented screw was a risk factor for vein leakage (OR 0.58; 95% CI 0.44-0.77; P = 0.000). Furthermore, the doses of cement (OR 0.79; 95% CI 0.61-0.99; P = 0.038) and the position of screw (OR 0.39; 95% CI 0.29-0.53; P = 0.000) were identified as risk factors for type S, and the doses of bone cement (OR 0.37; 95% CI 0.25-0.54; P = 0.000) and the position of the tip of screw (OR 0.07; 95% CI 0.04-0.13; P = 0.000) were risk factors for type B.

CONCLUSIONS

CAPSI bears a high risk of asymptomatic CL, with a higher rate of leakage into segmental veins and basivertebral veins. As is known, more augmented screws and larger doses of cement are risk factors for veins leakage (type S and type B), while the tip of screw approaching to the midline of the vertebral body is another risk factor to type B. Thus, the CL could be reduced by the amelioration of operative techniques and procedures. These slides can be retrieved under Electronic Supplementary Material.

Mineralized Collagen Modified Polymethyl Methacrylate Bone Cement for Osteoporotic Compression Vertebral Fracture at 1-Year Follow-up

STUDY DESIGN

Retrospective comparative study.

OBJECTIVE

This study aimed to compare the clinical effects and imaging features of polymethyl methacrylate (PMMA) bone cement with and without mineralized collagen (MC) in percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs).

SUMMARY OF BACKGROUND DATA

PKP with PMMA is widely performed for OVCF. However, numerous complications have also been reported about the PMMA bone cement. Moreover, PMMA bone cement with and without MC have not been compared with respect to their postoperative efficacy and long-term follow-up.

METHODS

From July 2016 to July 2017, 105 OVCF patients were randomly divided into two groups based on their PKP treatment: MC-PMMA group and PMMA group. Clinical operation, cement leakage, Oswestry Disability Index, visual analog scale, height of the fractured vertebrae, Cobb angle, refracture of the adjacent vertebra, recompression, and computed tomography values of the injured vertebra were compared between the two groups postoperatively and after 1-year follow-up.

RESULTS

Clinical operation showed no differences between the two groups. Visual analog scale scores, Oswestry Disability Index scores, and Cobb angles showed statistically significant differences between the two groups after 1-year follow-up. The height of the vertebral body showed significant difference at 3 days postoperatively and preoperatively in each group and significant difference after 1 year between the two groups. The rate of refracture and leakage of the MC-PMMA group was lower than that of the PMMA group. The computed tomography value of the MC-PMMA group was obviously higher than that of the PMMA group after 1-year follow-up.

CONCLUSION

MC-modified PMMA did not change the beneficial properties of PMMA. This new bone cement has better biocompatibility, can form a stable structure in the vertebral body, and improve the prognosis of patients by reducing pain and reoperation.

LEVEL OF EVIDENCE

3.

Thoracic Radicular Pain Caused by Extravertebral Gas and Fluid Collections Associated with Osteoporotic Vertebral Fracture Containing a Vacuum Cleft

The present study documents a phenomenon, which has received little attention despite its potential clinical importance. An 87-year-old woman presented with barely reported extravertebral gas and fluid collections probably originating from the contents of the adjacent cleft within the T10 collapsed osteoporotic vertebra. Her chief complaint was intractable pain radiating over the left thorax suggestive of intercostal neuralgia. The pain intensified when sitting up from a lateral decubitus position, correlating with a posture-related radiologic change of the intravertebral cleft, which appeared with a decubitus position and disappeared with a sitting position. Because these extravertebral collections were located where the 10th thoracic nerve root just exits the intervertebral foramina, her chest pain of a posture-dependent nature most likely resulted from nerve root compression by extravertebral gas and fluid forced out of the vertebral cleft. Posterior spinal fusion with pedicle screw instrumentation resulted in a complete resolution of the chest pain with disappearance of the extravertebral gas and fluid accumulations. An awareness of the possibility that the intravertebral cleft could communicate with the extravertebral space close to the nerve root will help avoid neurologic complications caused by bone cement leakage during vertebroplasty.

The Optimal Volume Fraction in Percutaneous Vertebroplasty Evaluated by Pain Relief, Cement Dispersion, and Cement Leakage: A Prospective Cohort Study of 130 Patients with Painful Osteoporotic Vertebral Compression Fracture in the Thoracolumbar Vertebra

OBJECTIVE

To probe the relationship among cement volume/fraction, imaging features of cement distribution, and pain relief and then to evaluate the optimal volume during percutaneous vertebroplasty.

METHODS

From January 2014 to January 2017, a total of 130 patients eligible for inclusion criteria were enrolled in this prospective cohort study. According to the different degrees of pain relief, cement leakage, and cement distribution, all patients were allocated to 2 groups. Clinical and radiologic characteristics were assessed to identify independent factors influencing pain relief, cement leakage, and cement distribution, including age, sex, fracture age, bone mineral density, operation time, fracture level, fracture type, modified semiquantitative severity grade, intravertebral cleft, cortical disruption in the vertebral wall, endplate disruption, type of nutrient foramen, fractured vertebral body volume, intravertebral cement volume, and volume fraction. A receiver operating characteristic curve was used to analyze the diagnostic value of the cement volume/fraction and then to obtain the optional cut-off value.

RESULTS

The preoperative visual analog scale scores in the responders versus nonresponders patient groups were 7.37 ± 0.61 versus 7.87 ± 0.92 and the postoperative VAS scores in the responders versus nonresponders were 2.04 ± 0.61 versus 4.33 ± 0.49 at 1 week. There were no independent factors influencing pain relief. There were 95 (73.08%) patients who experienced cement leakage, and cortical disruption in the vertebral wall and cement fraction percentage were identified as independent risk factors by binary logistic regression analysis (adjusted odds ratio [OR] 2.935, 95% confidence interval [95% CI] 1.214-7.092, P = 0.017); (adjusted OR 1.134, 95% CI 1.026-1.254, P = 0.014). The area under the receiver-operating characteristic curve of volume fraction (VF%) was 0.658 (95% CI 0.549-0.768, P = 0.006 < 0.05). The cut-off value of VF% for cement leakage was 21.545%, with a sensitivity of 69.50% and a specificity of 60.00%. The incidence of favorable cement distribution was 74.62% (97/130), and VF% were identified as independent protective factors (adjusted OR 1.185, 95% CI 1.067-1.317, P = 0.002) The area under the receiver-operating characteristic curve of VF% was 0.686 (95% CI 0.571-0.802, P = 0.001 < 0.05). The cut-off value of VF% to reach a favorable cement distribution was 19.78%, with a sensitivity of 86.60% and a specificity of 51.50%.

CONCLUSIONS

In osteoporotic vertebral compression fracture with mild/moderate fracture severity at the single thoracolumbar level, the intravertebral cement volume of 4-6 mL could relieve pain rapidly. The optimal VF% was 19.78%, which could achieve satisfactory cement distribution. With the increase of VF%, the incidence of cement leakage would also increase.

Analysis of risk factors causing short-term cement leakages and long-term complications after percutaneous kyphoplasty for osteoporotic vertebral compression fractures

Background Percutaneous kyphoplasty (PKP) is a common treatment modality for painful osteoporotic vertebral compression fractures (OVCFs). Pre- and postoperative identification of risk factors for cement leakage and follow-up complications would therefore be helpful but has not been systematically investigated. Purpose To evaluate pre- and postoperative risk factors for the occurrence of short-term cement leakages and long-term complications after PKP for OVCFs. Material and Methods A total of 283 vertebrae with PKP in 239 patients were investigated. Possible risk factors causing cement leakage and complications during follow-up periods were retrospectively assessed using multivariate analysis. Cement leakage in general, three fundamental leakage types, and complications during follow-up period were directly identified through postoperative computed tomography (CT). Results Generally, the presence of cortical disruption ( P = 0.001), large volume of cement ( P = 0.012), and low bone mineral density (BMD) ( P = 0.002) were three strong predictors for cement leakage. While the presence of intravertebral cleft and Schmorl nodes ( P = 0.045 and 0.025, respectively) were respectively identified as additional risk factors for paravertebral and intradiscal subtype of cortical (C-type) leakages. In terms of follow-up complications, occurrence of cortical leakage was a strong risk factor both for new VCFs ( P = 0.043) and for recompression ( P = 0.004). Conclusion The presence of cortical disruption, large volume of cement, and low BMD of treated level are general but strong predictors for cement leakage. The presence of intravertebral cleft and Schmorl nodes are additional risk factors for cortical leakage. During follow-up, the occurrence of C-type leakage is a strong risk factor, for both new VCFs and recompression.

Cement leakage in osteoporotic vertebral compression fractures with cortical defect using high-viscosity bone cement during unilateral percutaneous kyphoplasty surgery

The purpose of this study was to investigate cement leakage (CL) in osteoporotic vertebral compression fractures (OVCFs) with cortical defect using high-viscosity bone cement during unilateral percutaneous kyphoplasty (PKP) surgery.This study included a series of 77 patients (23 males, 54 females) with single level osteoporotic vertebral body fracture (OVCF) who underwent unilateral PKP in our hospital. Preoperative x-ray, computed tomography (CT) scan, and 3-dimensional reconstructions were studied. During the PKP procedure, needle was carefully put to avoid too near to the cortical defect according to CT image. High-viscosity bone cement was used via unilateral PKP. Radiographic outcomes were evaluated by assessment of vertebral body wall breakage, fracture type, and vertebral body change. The exact rate of CL was analyzed.A total of 77 patients with single-level OVCF were included in this study. The mean age of the patients was 74.8 ± 8.0 years. Among these cases, 7 (9.1%) involved the thoracic spine (T3-T10), 60 (77.9%) involved the thoracolumbar spine (T10-L2), and 10 (13.0%) involved the lumbar spine (L3-L5). There were 27 vertebral bodies found posterior wall breakage, 51 vertebral bodies found endplate breakage, and 49 vertebral bodies found anterior-lateral wall breakage. CT scan was more efficient in detecting vertebral body wall breakage and CL than x-ray (P < .001). No neurological symptoms were found after surgery. Both cases with CL (CL group) and cases without cement leakage (NCL group) experienced vertebral height restoration (HR) with similar cement volume CV. There were no significant difference between the two groups about the parameter HR and CV. Severe vertebral body fracture and biconcave fracture had more CL than other groups. OVCF cases with cortical defect had more CL rate than those without cortical defect; however, no significant difference was found in the correlation between vertebral wall breakage and CL.Cortical defect remains a potential risk of CL during PKP surgery. Careful preoperative evaluation and using high-viscosity bone cement during the unilateral PKP procedure could prevent serious leakage and clinical symptoms.

Is There a Dose-Response Relationship of Cement Volume With Cement Leakage and Pain Relief After Vertebroplasty?

The aim of this study was to determine if there were dose–response relationships of cement volume with cement leakage and pain relief after percutaneous vertebroplasty (PVP) for osteoporosis vertebral compression fractures (OVCFs). We collected the patient and procedural characteristics on 108 patients with OVCFs in our hospital who received PVP. Univariate and multivariate analyses were performed to explore the relationships between these potential influential variables and cement leakage and pain relief at 1 month postoperatively. Multivariate linear and logistic regression analyses were conducted with the pain score reduction and the bone cement leakage as dependent variables and the potential risk factors as independent variables, respectively. The results showed that the independent risk factors for the pain relief were the cement volume injected and fracture age, and for bone cement leakage were the cement volume injected and low-viscosity cement. In conclusion, the present study indicated that there were positive dose–response correlation relationships of cement volume with the incidence of cement leakage and the degree of pain relief after PVP, respectively. Thus, the cement should be injected into the vertebrae as much as possible during the PVP procedure.