Percutaneous balloon kyphoplasty in the treatment of painful vertebral compression fractures: Effect on local kyphosis and one-year outcomes in pain and disability

Machine Learning Applications for the Prediction of Bone Cement Leakage in Percutaneous Vertebroplasty

Background: Bone cement leakage is a common complication of percutaneous vertebroplasty and it could be life-threatening to some extent. The aim of this study was to develop a machine learning model for predicting the risk of cement leakage in patients with osteoporotic vertebral compression fractures undergoing percutaneous vertebroplasty. Furthermore, we developed an online calculator for clinical application. Methods: This was a retrospective study including 385 patients, who had osteoporotic vertebral compression fracture disease and underwent surgery at the Department of Spine Surgery, Liuzhou People's Hospital from June 2016 to June 2018. Combing the patient's clinical characteristics variables, we applied six machine learning (ML) algorithms to develop the predictive models, including logistic regression (LR), Gradient boosting machine (GBM), Extreme gradient boosting (XGB), Random Forest (RF), Decision Tree (DT) and Multilayer perceptron (MLP), which could predict the risk of bone cement leakage. We tested the results with ten-fold cross-validation, which calculated the Area Under Curve (AUC) of the six models and selected the model with the highest AUC as the excellent performing model to build the web calculator. Results: The results showed that Injection volume of bone cement, Surgery time and Multiple vertebral fracture were all independent predictors of bone cement leakage by using multivariate logistic regression analysis in the 385 observation subjects. Furthermore, Heatmap revealed the relative proportions of the 15 clinical variables. In bone cement leakage prediction, the AUC of the six ML algorithms ranged from 0.633 to 0.898, while the RF model had an AUC of 0.898 and was used as the best performing ML Web calculator (https://share.streamlit.io/liuwencai0/pvp_leakage/main/pvp_leakage) was developed to estimate the risk of bone cement leakage that each patient undergoing vertebroplasty. Conclusion: It achieved a good prediction for the occurrence of bone cement leakage with our ML model. The Web calculator concluded based on RF model can help orthopedist to make more individual and rational clinical strategies.

Shape-memory balloon offering simultaneous thermo/chemotherapies to improve anti-osteosarcoma efficacy

This paper proposes a shape-memory balloon (SMB) to improve bone cement injection efficiency and postoperative thermo/chemotherapy for bone tumors. The SMB consists of biodegradable poly(ε-caprolactone) (PCL), an anticancer drug (doxorubicin, DOX), and heat-generating magnetic nanoparticles (MNPs). The balloon shape is fabricated in a mold by crosslinking PCL macromonomers with DOX and MNPs. The mechanical properties and shape-transition temperature (approximately 40 °C) of the SMB are modulated by adjusting the molecular weight of PCL and the crosslinking density. This allows safe inflation at the affected site with a 400% expansion rate by simple blow molding. The expanded shape is temporarily memorized at 37 °C, and the computed tomography image shows that the bone cement is successfully injected without extra pressure or leakage. The SMB releases DOX for over 4 weeks, allowing a prolonged effect at the local site. The local dosing is constant as the medication is continuously released, demonstrating an ON-OFF switchable heating/cooling response to alternating magnetic field irradiation. In vitro cytotoxic studies have demonstrated that heat generation/drug release and only drug release from the balloon kill approximately 99% and 60% of human osteosarcoma cells, respectively. The proposed SMB is promising in postoperative local thermo/chemotherapy for bone tumors.

[Effectiveness of synchronous unilateral percutaneous kyphoplasty in the treatment of double noncontiguous thoracolumbar osteoporotic vertebral compression fractures]

OBJECTIVE

To investigate the effectiveness of synchronous unilateral percutaneous kyphoplasty (PKP) in the treatment of double noncontiguous thoracolumbar osteoporotic vertebral compression fracture (OVCF).

METHODS

Between December 2018 and September 2020, 27 patients with double noncontiguous thoracolumbar OVCF were treated by synchronous unilateral PKP. There were 11 males and 16 females, with an average age of 75.4 years (range, 66-92 years). The fractures were caused by falls in 22 cases and sprains in 5 cases. The time from injury to hospital admission was 0.5-7.0 days, with an average of 2.1 days. The fractured vertebrae located at T 9 in 2 cases, T 10 in 3 cases, T 11 in 10 cases, T 12 in 15 cases, L 1 in 12 cases, L 2 in 6 cases, L 3 in 4 cases, and L 4 in 2 cases. The volume of bone cement injected into each vertebral body, operation time, and intraoperative fluoroscopy times were recorded. Anteroposterior and lateral X-ray films of thoracolumbar spine were taken to observe the anterior height of the injured vertebra, the Cobb angle of kyphosis, and the diffusion and good distribution rate of bone cement in the thoracolumbar spine. Visual analogue scale (VAS) score and Oswestry disability index (ODI) were used to evaluate the pain and functional improvement.

RESULTS

All operations completed successfully. The operation time was 34-70 minutes, with an average of 45.4 minutes. The intraoperative fluoroscopy was 21- 60 times, with an average of 38.6 times. The volume of bone cement injected into each vertebral body was 2-9 mL, with an average of 4.3 mL. All patients were followed up 6-21 months, with an average of 11.3 months. X-ray film reexamination showed that the anterior height of the injured vertebra and Cobb angle at each time point after operation were significantly improved than those before operation ( P<0.05), and there was no significant difference between different time points after operation ( P>0.05). The distribution of bone cement was excellent in 40 vertebral bodies, good in 13 vertebral bodies, and poor in 1 vertebral body, and the excellent and good rate was 98.1% (53/54). The pain of all patients significantly relieved or disappeared, and the function improved. The VAS score and ODI at each time point after operation were significantly lower than those before operation ( P<0.05), and there was no significant difference between different time points after operation ( P>0.05).

CONCLUSION

For the double noncontiguous thoracolumbar OVCF, the synchronous unilateral PKP has the advantages of simple puncture, less trauma, less intraoperative fluoroscopy, shorter operation time, satisfactory distribution of bone cement, etc. It can restore the height of the vertebral body, correct the kyphotic angle, significantly alleviate the pain, and improve the function.

High-viscosity bone cement for vertebral compression fractures: a prospective study on intravertebral diffusion and leakage of bone cement

Background

Bone cement leakage causes severe complication following percutaneous vertebroplasty. This study probed the diffusion and leakage status of bone cement injected within diverged time duration, so as to find the optimal injection time for bone cement.

Methods

A total of 70 patients with osteoporotic vertebral compression fractures with a symptom of low back pain, who underwent treatment at hospital were enrolled in this study. Patients were randomized into three groups: < 180 s, 180–300, and > 300 s of injection time duration from the beginning to the completion of the injection. The scenarios of vertebral bone cement leakage and diffusion were inspected using postoperative CT.

Results

The diffusion coefficient was higher in group A than in group B whereas it was higher in group B than in group C, but without statistical significance among the three groups. The leakage rate was without statistical significance among the three groups. The injection time of bone cement was negatively correlated with the diffusion coefficient, at the correlation coefficient of − 0.253.

Conclusions

The diffusion coefficient of high-viscosity bone cement is negatively correlated with the injection time, and the leakage rate of high-viscosity bone cement does not reduce with the prolongation of injection time.

Percutaneous balloon kyphoplasty in the treatment of vertebral compression fractures: a single-center analysis of pain and quality of life outcomes

BACKGROUND

Vertebral body compression fractures are one of the most common causes of disability and morbidity, especially among the elderly population. The present study was performed in order to evaluate the effect of percutaneous balloon kyphoplasty (BKP) on patients' pain and quality of life (QOL) in Iran.

METHODS

The study was conducted on a consecutive series of 54 patients with symptomatic vertebral compression fractures who failed conservative management between 2014 and 2017. A quasi-experimental design was employed in which the pain severity, quality of life, and kyphotic angle were measured before and 3 and 12 months after the PBK procedure. Pain and quality of life outcomes were determined using a Visual Analogue Scale (VAS) for Pain and the 12-Item Short Form Health Survey (SF-12) for QOL.

RESULTS

Excellent improvement in VAS was documented at 3 and 12 months after the BKP procedure (p = 0.001). Improvement at 3 months was maintained through the 12 months follow-up period. A statistically significant improvement in QOL was documented at 3 months after BKP that continued to improve through 12 months follow-up. The mean kyphotic angle before PBK was 19.4 ± 5.3 degrees which after 3 months improved to 12.8 ± 3.1 degrees; this reduction was significant (p < 0.001). No new fractures occurred during the follow-up period.

CONCLUSION

Balloon kyphoplasty was determined to be a safe and successful method for treating symptomatic vertebral compression fractures. It leads to significant pain relief, an improvement in self-reported QOL measures, and correction in kyphotic deformity.

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.

Predictors of favorable quality of life outcome following kyphoplasty and vertebroplasty

OBJECTIVE

In 2009, 2 randomized controlled trials demonstrated no improvement in pain following vertebral augmentation compared with sham surgery. However, a recent randomized trial demonstrated significant pain relief in patients following vertebroplasty compared to controls treated with conservative medical management. This study is a retrospective review of prospectively collected patient-reported quality of life (QOL) outcomes. The authors hypothesized that vertebral augmentation procedures offer a QOL benefit, but that this benefit would be diminished in patients with a history of depression and/or in patients undergoing vertebral augmentation at more than 1 level.

METHODS

Multivariable linear regression was used to identify predictors of postoperative pain assessed using the Pain Disability Questionnaire (PDQ), Patient Health Questionnaire 9 (PHQ-9), and EQ-5D scores. Eleven candidate predictors were selected a priori: age, sex, smoking history, coronary artery disease, depression, diabetes, procedure location (thoracic, lumbar), BMI, prior spine surgery, procedure indication (metastases, osteoporosis/osteopenia, other), and number of levels (1, 2, 3, or more).

RESULTS

A total of 143 patients were included in the study. For each 10-year increase in age, postoperative PDQ scores decreased (improved) by 9.7 points (p < 0.001). Patients with osteoporosis/osteopenia had significantly higher (worse) postoperative PDQ scores (+17.97, p = 0.028) than patients with metastatic lesions. Male sex was associated with higher (worse) postoperative PHQ-9 scores (+2.48, p = 0.010). Compared to single-level augmentation, operations at 2 levels were associated with significantly higher PHQ-9 scores (+2.58, p = 0.017). Current smokers had significantly lower PHQ-9 scores (-1.98, p = 0.023) than never smokers. No predictors were associated with significantly different EQ-5D score.

CONCLUSIONS

Variables associated with worse postoperative PDQ scores included younger age and osteoporosis/osteopenia. Variables associated with decreased (better) postoperative PHQ-9 scores included female sex, single operative vertebral level, and positive smoking status (i.e., current smoker). These clinically relevant predictors may permit identification of patients who may benefit from vertebral augmentation.

Is it necessary to approach the compressed vertebra bilaterally during the process of PKP?

OBJECTIVE

To assess the clinical and radiological outcomes following unilateral or bilateral approach in percutaneous kyphoplasty (PKP) for treatment of osteoporotic vertebral compression fractures (OVCF).

DESIGN

Prospective comparative study.

SETTING

University affiliated hospital.

PARICIPANTS

From 2012 through 2016, those MRI-diagnosed single-level lumbar OVCF patients.

INTERVENTIONS

They were randomly assigned for treatment with unilateral or bilateral PKP.

OUTCOME MEASURES

We assessed the patient' health status with the Oswestry Disability Index (ODI) questionnaire. Anteroposterior and lateral standing radiographs were obtained to measure the vertebral height and kyphotic angle of the vertebral body in all patients.

RESULTS

Eighty-five patients were finally enrolled in this investigation, including 42 in the unilateral and 43 in the bilateral group. The operation time, PMMA volume, radiation dose was 25.6 ± 4.2 minutes, 6.2 ± 3.5 ml and 0.88 ± 0.28 mSv in the unilateral group, while 36.6 ± 8.7 minutes, 8.5 ± 2.2 ml and 1.89 ± 1.05 mSv in the bilateral group, respectively (P < 0.05). The postoperative VAS and ODI were 2.7 ± 1.2 and 19.8 ± 6.4 compared to preoperative 8.7 ± 1.6 and 35.2 ± 4.3 in unilateral group, while 2.6 ± 1.3 and 19.7 ± 2.6 compared to preoperative 8.5 ± 1.3 and 36.7 ± 3.6 in bilateral group, respectively (P > 0.05).

CONCLUSION

Both bilateral and unilateral PKP are relatively safe and provide effective treatment for patients with painful OVCF. However, unilateral PKP need less radiation dose, operation time and PMMA volume.

Percutaneous Balloon Kyphoplasty Vertebral Augmentation for Compression Fracture Due to Vertebral Metastasis: A 12-Month Retrospective Clinical Study in 72 Patients

Background

Vertebral compression fracture is common in osteoporosis, but can also occur due to bone metastases, for which current treatment options are limited and include bone-strengthening with cement and supportive care. Kyphoplasty is a surgical method of bone augmentation that can reduce pain, stabilize vertebral bone, and restore some or all of the vertebral body height. The aim of this study was to investigate the clinical results of balloon kyphoplasty in the correction of vertebral deformity due to metastatic vertebral compression fracture.

Material/Methods

A retrospective clinical study included 72 patients (82 vertebral bodies) with metastases resulting in vertebral compression fracture, treated by percutaneous balloon kyphoplasty; 9 patients were found incidentally to have vertebral metastases. Bone mineral density (BMD) levels were measured. Patient responses from questionnaires, including the visual analog scale (VAS) for pain intensity, and the Oswestry Disability Index (ODI) for disability, were scored. The local kyphosis angle (KA) and the vertebral height ratio (VHR) were measured. All patients were followed up for 12 months. The initial postoperative and 12-month postoperative values, and the preoperative and postoperative values were compared.

Results

Following balloon kyphoplasty, the KA, VHR, VAS, and ODI scores significantly improved at the final 12-month follow-up compared with preoperative levels (p<0.05, and p<0.001). There was cement leakage in 6 procedures (8.3%) and adjacent segment fracture in 11 procedures (15.2%).

Conclusions

Balloon kyphoplasty was an effective method to reduce pain, reduce disability, and improve quality of life by eliminating kyphotic deformity in pathological vertebral compression fractures due to vertebral metastases.

Analysis of Pre- and Postoperative Pain Variation in Osteoporotic Vertebral Compression Fracture Patients Undergoing Kyphoplasty

Background

Balloon kyphoplasty (KP) has been widely applied in the treatment of elderly patients with osteoporosis vertebral compression fracture (OVCF), but there has been little research on the pain relief effect. Therefore, we performed this study of patients who received KP. The study included a set of fluoroscopy tests and follow-up evaluation, which aimed to verify the effectiveness of kyphoplasty in controlling back pain associated with OVCFs.

Material/Methods

Forty-three OVCF patients underwent kyphoplasty: 21 were allocated to an intervention group and 22 were allocated to a control group, and the 2 groups received treatment with different KP instruments. The variation of vertebral height was measured on X-ray and change of signal of MRI was recorded. The pain was assessed by VAS score and diagram, and physical function was evaluated by ODI. The complications after surgery were recorded and collated during 2 years of follow-up.

Results

The intervention group showed no significant difference on the VAS and ODI compared to the control group (p>0.05). There was no difference in the VAS with different degrees of radiological change (p>0.05). Signal change on MRI imaging was rare.

Conclusions

Kyphoplasty is a positive way to alleviate early-onset OVCF pain. The change of BME extent in the treated level is unrelated to the relief of back pain after KP.

Percutaneous Balloon Kyphoplasty in Treatment of Painful Osteoporotic Occult Vertebral Fracture: A Retrospective Study of 89 Cases

BACKGROUND The definition of a vertebral fracture is usually based on the presence of a deformation of the vertebral body and this can be misleading in the presence of a fracture without radiologic collapse with the definition of occult osteoporotic vertebral fractures (OOVFs). STIR sequence of MRI images showing hyperintensity signal was the most confirmative screening examination used to determine the presence of painful OOVFs. To date, clinical management of OOVFs has been rarely discussed. MATERIAL AND METHODS Between 2011 and 2013, 89 patients suffering from painful OOVFs underwent 142 percutaneous balloon kyphoplasty (PKP) procedures. Outcome data (mean variation of anterior and middle vertebral body height, visual analog scale [VAS] scores, Oswestry Disability Index [ODI] scores, and SF-36 scores) were recorded preoperatively, postoperatively, and at 1 month, 6 months, and 2 year after treatment, to evaluate the results. RESULTS We successfully treated 89 patients (142 vertebral bodies) with PKP. Cement leakages were observed in 12 (8.45%) treated vertebral bodies and there were 5 new adjacent vertebral fractures during the follow-up period. The mean variation of anterior and middle vertebral body height changed from 96.5±3.4% preoperatively to 97.2±2.5% postoperatively (p>0.05) and from 96.3±2.8% preoperatively to 97.9±3.1% postoperatively (p>0.05), respectively. The mean VAS scores were reduced significantly from pre-surgery to post-surgery (8.3±1.2 to 2.9±0.7; p<0.05), as was the ODI score (76.4±12.5 to 26.7±5.6; p<0.05). The SF-36 scores, including Bodily Pain (BF), Vitality (VT), Physical Function (PF), and Social Functioning (SF), all showed notable improvement (P<0.05). These variations were maintained during the 2-year follow-up period. CONCLUSIONS PKP is a safe and effective method in the treatment of painful OOVFs.