Appropriate Cement Volume in Vertebroplasty: A Multivariate Analysis with Short-Term Follow-Up

The significance of the best puncture side bone cement/vertebral volume ratio to prevent paravertebral vein leakage of bone cement during vertebroplasty: a retrospective study

OBJECTIVES

To verify the clinical significance of the best puncture-side bone cement/vertebral volume ratio (PSBCV/VV%) and bone cement leakage in paravertebral veins during vertebroplasty.

METHODS

This was a retrospective analysis of a total of 210 patients from September 2021 to December 2022, who were divided into an observation group (110 patients) and a control group (100 patients). In the observation group, patients' preoperative computed tomography (CT) data were imported into Mimics software, and the VV was calculated using the three-dimensional (3D) reconstruction function. Then, based on the best PSBCV/VV% of 13.68% determined in a previous study, the optimal PSBCV to be injected during vertebroplasty was calculated. In the control group, vertebroplasty was performed directly using the conventional method. The incidence of cement leakage into paravertebral veins was observed postoperatively in both groups.

RESULTS

There were no statistically significant differences (P > 0.05) in the evaluated indicators between the two groups pre- or postoperatively, including the anterior vertebral margin height, mid-vertebral height, injured vertebral Cobb angle, visual analogue scale (VAS) score, and Oswestry Disability Index (ODI). Intragroup comparisons showed improvements in the anterior vertebral height, mid-vertebral height, injured vertebral Cobb angle, VAS score, and ODI after surgery compared with before surgery (P < 0.05). In the observation group, there were 3 cases of cement leakage into the paravertebral veins, for a leakage rate of 2.7%. In the control group, there were 11 cases of cement leakage into the paravertebral veins, for a leakage rate of 11%. The difference in the leakage rate between the two groups was statistically significant (P = 0.016).

CONCLUSION

In vertebroplasty, preoperative VV calculations using Mimics software, combined with calculation of the PSBCV according to the best PSBCV/VV% (13.68%), can effectively prevent leakage of bone cement into paravertebral veins and further prevent serious life-threatening complications such as pulmonary embolism.

Computer-assisted simulated workplace-based assessment in surgery: application of the universal framework of intraoperative performance within a mixed-reality simulation

Objectives

Workplace-based assessment (WBA) is a key requirement of competency-based medical education in postgraduate surgical education. Although simulated workplace-based assessment (SWBA) has been proposed to complement WBA, it is insufficiently adopted in surgical education. In particular, approaches to criterion-referenced and automated assessment of intraoperative surgical competency in contextualized SWBA settings are missing.Main objectives were (1) application of the universal framework of intraoperative performance and exemplary adaptation to spine surgery (vertebroplasty); (2) development of computer-assisted assessment based on criterion-referenced metrics; and (3) implementation in contextualized, team-based operating room (OR) simulation, and evaluation of validity.

Design

Multistage development and assessment study: (1) expert-based definition of performance indicators based on framework's performance domains; (2) development of respective assessment metrics based on preoperative planning and intraoperative performance data; (3) implementation in mixed-reality OR simulation and assessment of surgeons operating in a confederate team. Statistical analyses included internal consistency and interdomain associations, correlations with experience, and technical and non-technical performances.

Setting

Surgical simulation center. Full surgical team set-up within mixed-reality OR simulation.

Participants

Eleven surgeons were recruited from two teaching hospitals. Eligibility criteria included surgical specialists in orthopedic, trauma, or neurosurgery with prior VP or kyphoplasty experience.

Main outcome measures

Computer-assisted assessment of surgeons' intraoperative performance.

Results

Performance scores were associated with surgeons' experience, observational assessment (Objective Structured Assessment of Technical Skill) scores and overall pass/fail ratings. Results provide strong evidence for validity of our computer-assisted SWBA approach. Diverse indicators of surgeons' technical and non-technical performances could be quantified and captured.

Conclusions

This study is the first to investigate computer-assisted assessment based on a competency framework in authentic, contextualized team-based OR simulation. Our approach discriminates surgical competency across the domains of intraoperative performance. It advances previous automated assessment based on the use of current surgical simulators in decontextualized settings. Our findings inform future use of computer-assisted multidomain competency assessments of surgeons using SWBA approaches.

Correlation Analysis between Residual Pain after Vertebral Augmentation and the Diffusion Distribution of Bone Cement: A Retrospective Cohort Study

Objective

To explore the influence and potential factors of the bone cement dispersion state on residual pain after vertebral augmentation.

Methods

The cases included in this retrospective cohort study were patients treated with vertebral augmentation (VA) for osteoporotic vertebral compression fractures (OVCFs) between July 2018 and June 2021. According to the type of cement diffusion distribution, the patients were divided into a sufficient diffusion group (Group A) and an insufficient diffusion group (Group B). The differences in the baseline data, visual analog scale (VAS), Oswestry disability index score (ODI), injured vertebral height (IVH), and local kyphosis angle (LKA) between the two groups were analyzed. Assessments were performed preoperatively on the 2nd day postoperation and at the last follow-up. The imaging data of injured vertebrae were accurately reconstructed by a GE AW4.7 workstation, and the differences in the vertebral body volume, bone cement volume, and bone cement volume ratio were compared between the groups.

Result

After screening, 36 patients were included. (1) The postoperative VAS and ODI scores of the two groups were significantly improved compared with the preoperative scores. (2) On the 2nd day postoperation and the last follow-up, the VAS and ODI scores of Group A were significantly different from those of Group B, and Group A outperformed Group B. (3) The IVH and LKA of the two groups were improved after the operation, and no significant difference was found between the groups. (4) Significant differences were found in the bone cement volume and bone cement volume ratio between the groups, and Group A was larger than Group B.

Conclusions

Sufficient bone cement diffusion can reduce residual pain after vertebral augmentation.

Biomechanics of the unilateral posterosuperior, unipedicular, and bipedicular approaches for treatment by percutaneous vertebroplasty: a comparative study

Percutaneous vertebroplasty (PVP) via the unilateral posterosuperior approach has achieved good clinical results for the treatment of osteoporotic vertebral compression fractures. This study compared the biomechanical performance of a single vertebral body after PVP by the unilateral posterosuperior, unipedicular, and bipedicular approaches. Twenty-one vertebral bodies from the osteoporotic spine segments (T11-L1) of seven older female cadavers were randomly assigned to the unipedicular (group A), bipedicular (group B), or unilateral posterosuperior approach group (group C). After constructing the fracture compression model, PVP was performed by the different approaches. CT scans showed symmetrical, evenly distributed bone cement in groups B and C and unilaterally distributed cement in group A. The recovery rates of the anterior vertebral body height in groups B and C were significantly higher than those in group A after PVP (P<0.05). The left curvature elastic moduli after PVP were significantly higher in group A than in groups B and C; however, the right curvature moduli in group A were lower than in the other groups (P<0.05). The flexion, extension, and vertical compression elastic moduli were lowest in group B (P<0.05). After PVP, failure strength and stiffness in groups B and C were comparable (P>0.05) and higher than those in group A (P<0.05). PVP through the unilateral posterosuperior approach was superior to the unipedicular approach and comparable to the bipedicular approach based on the biomechanical performance of a single vertebral body. Due to its safety, simplicity, and efficacy, the unilateral posterosuperior approach is recommended for clinical application.

Correlation analysis of the puncture-side bone cement/vertebral body volume ratio and bone cement leakage in the paravertebral vein in vertebroplasty

Objectives

To explore the influencing factors of bone cement leakage in the paravertebral vein after vertebroplasty for the treatment of osteoporotic vertebral compression fractures (OVCFs) and to determine the correlation between the puncture-side bone cement/vertebral body volume ratio and bone cement leakage in the paravertebral vein.

Methods

This was a retrospective analysis of 495 patients (585 vertebral bodies) with OVCFs treated from August 2018 to May 2021 in our hospital. The patients’ postoperative CT data were imported into Mimics software, and the three-dimensional(3D) reconstruction function was used to calculate the bone cement volume (BCV), puncture-side bone cement volume (PSBCV), and vertebral body volume (VBV); the bone cement/vertebral body volume ratio (BCV/VCV%) and puncture-side bone cement/vertebral body volume ratio (PSBCV/VCV%) were additionally calculated. Sex, Age, Body mass index(BMI), Bone density, BCV, PSBCV, VBV, BCV/VCV%, and PSBCV/VCV were compared between the leakage group and the non-leakage group. Logistic regression analysis was used to assess the correlations between the factors that statistically significantly differed between the two groups and the presence of leakage in the paravertebral veins. A receiver operating characteristic (ROC) curve was used to determine the diagnostic value of the PSBCV/VCV% and to obtain the optional cut-off value.

Results

A total of 102 males and 393 females with an average age of 72.89 (52 ~ 93) years were included in our study. There were 57 cases of cement leakage (59 vertebral bodies) in the paravertebral vein. There were 438 patients (526 vertebral bodies) without paravertebral cement leakage. Univariate analysis showed that the differences in sex, bone density, PSBCV, and PSBCV/VCV% between the two groups were statistically significant (P < 0.05). Logistic regression analysis showed that there were correlations between sex, bone density, and PSBCV/VCV% and the presence of paravertebral cement leakage (P < 0.05). The ROC curve showed that the area under the curve of the PSBCV/VCV% for the diagnosis of cement leakage in the paravertebral vein was greater than 0.65, and P < 0.05, indicating a diagnostic value. The best cut-off point for the diagnosis of paravertebral cement leakage with the PSBCV/VCV% was 13.68%, with a sensitivity of 84.7% and specificity of 37.8%.

Conclusion

Sex, bone density, and PSBCV/VCV% are risk factors for cement leakage in the paravertebral veins after vertebroplasty for the treatment of OVCFs; the PSBCV/VCV% is strongly associated with paravertebral venous leakage, and the optimal PSBCV/VCV% is 13.68%. When the PSBCV/VCV% exceeds the optimal value, the risk of cement leakage in the paravertebral vein becomes significantly increased.

Development and validation of a nomogram for predicting the probability of new vertebral compression fractures after vertebral augmentation of osteoporotic vertebral compression fractures

INTRODUCTION

New vertebral compression fractures (NVCFs) are adverse events after vertebral augmentation of osteoporotic vertebral compression fractures (OVCFs). Predicting the risk of vertebral compression fractures (VCFs) accurately after surgery is still a significant challenge for spinal surgeons. The aim of our study was to identify risk factors of NCVFs after vertebral augmentation of OVCFs and develop a nomogram.

METHODS

We retrospectively reviewed the medical records of patients with OVCFs who underwent percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). Patients were divided into the NVCFs group and control group, base on the patients with or without NVCFs within 2 years follow-up period after surgery. A training cohort of 403 patients diagnosed in our hospital from June 2014 to December 2016 was used for model development. The independent predictive factors of postoperative VCFs were determined by least absolute shrinkage and selection operator (LASSO) logistic regression, univariate analysis and multivariate logistic regression analysis. We provided a nomogram for predicting the risk of NVCFs based on independent predictive factors and used the receiver operating characteristic curve (ROC), calibration curve, and decision curve analyses (DCA) to evaluated the prognostic performance. After internal validation, the nomogram was further evaluated in a validation cohort of 159 patients included between January 2017 and June 2018.

RESULTS

Of the 403 patients in the training cohort, 49(12.16%) were NVCFs at an average of 16.7 (1 to 23) months within the 2 years follow-up period. Of the 159 patients in the validation cohort, 17(10.69%) were NVCFs at an average of 8.7 (1 to 15) months within the 2 years follow-up period. In the training cohort, the proportions of elderly patients older than 80 years were 32.65 and 13.56% in the NVCFs and control group, respectively (p = 0.003). The percentages of patients with previous fracture history were 26.53 and 12.71% in the NVCFs and control group, respectively (p = 0.010). The volume of bone cement were 4.43 ± 0.88 mL and 4.02 ± 1.13 mL in the NVCFs and Control group, respectively (p = 0.014). The differences have statistical significance in the bone cement leakage, bone cement dispersion, contact with endplate, anti-osteoporotic treatment, post-op Cobb angle and Cobb angle restoration characteristics between the two groups. The model was established by multivariate logistic regression analysis to obtain independent predictors. In the training and validation cohort, the AUC of the nomogram were 0.882 (95% confidence interval (CI), 0.824-0.940) and 0.869 (95% CI: 0.811-0.927), respectively. The C index of the nomogram was 0.886 in the training cohort and 0.893 in the validation cohort, demonstrating good discrimination. In the training and validation cohort, the optimal calibration curves demonstrated the coincidence between prediction and actual status, and the decision curve analysis demonstrated that the full model had the highest clinical net benefit across the entire range of threshold probabilities.

CONCLUSION

A nomogram for predicting NVCFs after vertebral augmentation was established and validated. For patients evaluated by this model with predictive high risk of developing postoperative VCFs, postoperative management strategies such as enhance osteoporosis-related health education and management should be considered.

The clinical efficacy and experience of bipedicular percutaneous vertebroplasty combined with postural reduction in the treatment of Kümmell's disease

Background

Kümmell’s disease is a special type of osteoporotic vertebral fracture that causes chronic low back pain and deformity, which seriously affects the living quality of patients. PVP is commonly used to treat osteoporotic vertebral fractures and can quickly relieve low back pain. So, the objective of this study was to analyze the clinical efficacy and experience of bipedicular percutaneous vertebroplasty combined with postural reduction for the treatment of Kümmell’s disease.

Methods

A retrospective analysis of patients with Kümmell’s disease who underwent bipedicular percutaneous vertebroplasty was conducted from February 2016 to May 2018. Operative time, VAS, bone cement injection volume, cement leakage rate, compression improvement of vertebral front edge and vertebral center, and correction degree of kyphosis were collected and analyzed meticulously.

Results

The operative time was 45.33 ± 7.64 min. The volume of bone cement injected was 5.38 ± 1.33 ml. The compression improvement of vertebral front edge was 7.31 ± 1.21%. The compression improvement of vertebral center was 10.34 ± 1.15% and the correction degree of kyphosis was − 2.73 ± 0.31゜. Bone cement leakage occurred in 6 of 39 patients (15.38%), but no clinical symptoms were observed. The VAS scores were significantly lower at 1 day after the surgery, 6 months and at the last follow-up than before the surgery (P = 0.000, respectively). The VAS score was lower at the last follow-up than at 1 day after the surgery (P = 0.001).

Conclusion

Bipedicular percutaneous vertebroplasty combined with postural reduction could achieve satisfactory analgesic effect in the treatment of Kümmell’s disease, and restore the height of the vertebral body and improve kyphosis to some extent.

Long Term Survival of Pathological Thoracolumbar Fractures Treated with Vertebroplasty: Analysis Using a Nationwide Insurance Claim Database

Background: There are still debates on the long-term outcome of treating pathological thoracolumbar fractures, including osteoporosis and oncologic problems, using vertebroplasty. Methods: We collected 8625 patients with pathological thoracolumbar fractures (ICD-9-CM codes 733.13 combined with 805.2 or 805.4) between the years of 2003 to 2013, from the two million random samples from the National Health Insurance Research Database in Taiwan. Survival analysis was conducted to estimate the mortality risks of different treatments, including vertebroplasty (n = 1389), conventional open surgery (n = 1219), or conservative treatment (n = 6017). A multivariable Cox proportional hazard model was constructed for adjustment of age, gender, comorbidities and complications. Results: Crude incidence rate of patients with pathological thoracolumbar fractures in Taiwan gradually increased year by year. Compared with conservative treatment, conventional open surgery and vertebroplasty seemed to improve long-term survival with adjusted hazard ratios (aHR) of 0.80 (95% confidence interval (CI) 0.70–0.93), and 0.87 (95% CI 0.77–0.99), respectively. The survival advantage of vertebroplasty appeared more evident for those aged over 75. However, we were unable to rule out confounding by indication. Conclusion: Although conventional open surgery would usually be the best choice for the treatment of patients with pathological thoracolumbar fractures, database information from current real-world practice appears to support vertebroplasty as a viable choice for elderly people over 75 years of age.

Cementoplasty of pelvic bone metastases: systematic assessment of lesion filling and other factors that could affect the clinical outcomes

OBJECTIVES

To evaluate lesion filling and other factors that could affect the clinical outcomes of cementoplasty for pelvic bone metastases.

METHODS

We retrospectively reviewed the files of 40 patients treated for 44 pelvic bone metastases, collected the parameters related to patients (pain relief evaluated on a visual analog scale, subsequent fractures, and need for surgery), lesions (size, cortical breach score, fracture, soft-tissue extension), and cementoplasty procedures (number of needles, volume of cement, percentage of lesion filling, cement leaks, residual acetabular roof defect), and performed a statistical analysis.

RESULTS

The lesions were on average 43.2 mm in diameter and the mean cortical breach score was 2.5 out of 6, with a pathological fracture in 14 lesions. The number of needles inserted was one in 32 out of 44, two in 10 out of 44, and three in 2 out of 44. On average, the volume of cement injected per lesion was 10.3 ml and the filling was 54.8%. Mild or moderate asymptomatic cement leakage occurred in 20 lesions (45.5%). The mean pain score was 84.2 mm before the procedure (with no correlation with lesion size, cortical breach score or fracture) and 45.6 mm at follow-up. The pain relief of 38.6 mm was statistically significant (p < 0.001) and did not correlate with the filling percentage. There were no fractures of the treated lesions at a mean follow-up of 355 days.

CONCLUSIONS

Cementoplasty of pelvic bone metastases appears effective for providing pain relief and may prevent subsequent fractures. We were unable to demonstrate a correlation between the lesion filling and the degree of pain relief.

Cement injection and postoperative vertebral fractures during vertebroplasty

Objective

Vertebroplasty is the most widely used method for treating osteoporotic vertebral compression fractures (OVCF). During this procedure, bone cement is injected into the vertebral body. Fracture and additional fractures can occur adjacent to the treatment site. Thus, we studied factors causing such vertebral fractures after vertebroplasty and calculated the appropriate amount of bone cement to inject.

Methods

From September 2012 to March 2016, 187 patients with OVCF undergoing vertebroplasty were selected, and 112 patients with complete follow-up information were selected. Of these, 28 had adjacent vertebral fractures (refracture group) during the follow-up period, and 84 patients had no adjacent vertebral fractures (control group). Then, sex, age, body weight, bone mineral density (BMD), and bone cement injection (bone cement injection volume and bone fracture vertebral volume percent) were compared.

Results

All patients had significant pain relief within 24 h (preoperative and postoperative [24 h later] VAS scores were 7.4 ± 0.8 and 2.3 ± 0.5, respectively). The age and weight were not statistically significantly different (P > 0.05). BMD values were statistically significantly different between groups as was sex (P < 0.05).

Conclusions

Bone cement injection volume, BMD values, and sex were statistically significantly related to adjacent vertebral fractures after vertebroplasty, and cement injection volumes exceeding 40.5% caused adjacent vertebral fractures.

Vertebroplasty for acute painful osteoporotic vertebral compression fractures: An update

Vertebral compression fractures (VCFs) are a common cause of back pain and disability and are usually osteoporotic in nature. Therapy aims to adequately control pain and allow early mobilisation and return of function while preventing additional fractures. A proportion of patients do not achieve adequate pain relief using conservative measures alone. Unwanted adverse effects from medications may also ensue. Vertebroplasty represents an alternative treatment option for VCFs. Patients with acute VCFs (≤6 weeks old) may gain the most benefit from vertebroplasty as healed fractures are not as amenable to cement injection. High-quality studies have reported conflicting results regarding the use of vertebroplasty in the treatment of acute VCFs. Despite high-quality evidence, varying study designs and heterogenous patient cohorts make interpretation of this data difficult. Only one sham-controlled randomised controlled trial (RCT) has evaluated vertebroplasty exclusively in patients with acute VCFs, reporting favourable results. Pooled data from RCTs also suggest vertebroplasty to be safe. This article provides a concise and critical review of the current literature regarding vertebroplasty for the treatment of acute VCFs.

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.