Vertebroplasty and kyphoplasty are associated with an increased risk of secondary vertebral compression fractures: a population-based cohort study

Risk of adjacent level fracture after percutaneous vertebroplasty and kyphoplasty vs natural history for the management of osteoporotic vertebral compression fractures: a network meta-analysis of randomized controlled trials

OBJECTIVES

Percutaneous vertebroplasty and kyphoplasty are common interventions for osteoporotic vertebral compression fractures. However, there is concern about an increased risk of adjacent-level fractures after treatment. This study aimed to compare the risk of adjacent-level fractures after vertebroplasty and kyphoplasty with the natural history after osteoporotic vertebral compression fractures.

MATERIALS AND METHODS

A network meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the risk of adjacent-level fractures after vertebroplasty and kyphoplasty compared to the natural history after osteoporotic vertebral compression fractures. Frequentist network meta-analysis was conducted using the "netmeta" package, and heterogeneity was assessed using Q statistics. The pooled risk ratio (RR) and 95% confidence intervals (CI) were calculated using random effects.

RESULTS

Twenty-three RCTs with a total of 2838 patients were included in the analysis. The network meta-analysis showed comparable risks of adjacent-level fractures between vertebroplasty, kyphoplasty, and natural history after osteoporotic vertebral compression fractures with a mean follow-up of 21.2 (range: 3-49.4 months). The pooled RR for adjacent-level fractures after kyphoplasty compared to natural history was 1.35 (95% CI, 0.78-2.34, p = 0.23) and for vertebroplasty compared to natural history was 1.16 (95% CI, 0.62-2.14) p = 0.51. The risk of bias assessment showed a low to moderate risk of bias among included RCTs.

CONCLUSION

There was no difference in the risk of adjacent-level fractures after vertebroplasty and kyphoplasty compared to natural history after osteoporotic vertebral compression fractures. The inclusion of a large patient number and network meta-analysis of RCTs serve evidence-based clinical practice.

CLINICAL RELEVANCE STATEMENT

The risk of adjacent-level fracture following percutaneous vertebroplasty or kyphoplasty is similar to that observed in the natural history after osteoporotic vertebral compression fractures.

KEY POINTS

RCTs have examined the risk of adjacent-level fracture after intervention for osteoporotic vertebral compression fractures. There was no difference between vertebroplasty and kyphoplasty patients compared to the natural disease history for adjacent compression fractures. This is strong evidence that interventional treatments for these fractures do not increase the risk of adjacent fractures.

Similarities and Differences in the Management of Patients with Osteoporotic Vertebral Fractures and Those with Rebound-Associated Vertebral Fractures Following Discontinuation of Denosumab

Rebound-associated vertebral fractures (RVFx) following denosumab discontinuation are typically multiple, are commonly associated with acute sharp pain, increase the risk of imminent fractures, and are pathogenetically different from common osteoporotic vertebral fractures (VFx). A clinically relevant question is whether patients with RVFx should be managed differently from patients with osteoporotic VFx. To address this question, we performed a systematic search of the PubMed database, and we reviewed current evidence on the optimal management of patients with RVFx. For pain relief of patients with RVFx, potent analgesics, often opioids, are essential. Information on the effectiveness of braces in these patients is scarce. Vertebroplasty and kyphoplasty are strongly contraindicated as they confer a substantial risk for new VFx. Exercise may be helpful, but again evidence is lacking. In contrast to patients with osteoporotic VFx, in whom initial treatment with bone-forming agents is recommended, patients with RVFx should initiate treatment with potent antiresorptives. To summarize, patients who have sustained RVFx following denosumab discontinuation are at a very high risk for new fractures, especially VFx. The management of such patients requires a multidisciplinary approach that should not be restricted to pain relief and administration of antiosteoporotic medication, but should also include back protection, early mobilization, and appropriate exercise.

Development and validation of a machine learning model to predict imminent new vertebral fractures after vertebral augmentation

BACKGROUND

Accurately predicting the occurrence of imminent new vertebral fractures (NVFs) in patients with osteoporotic vertebral compression fractures (OVCFs) undergoing vertebral augmentation (VA) is challenging with yet no effective approach. This study aim to examine a machine learning model based on radiomics signature and clinical factors in predicting imminent new vertebral fractures after vertebral augmentation.

METHODS

A total of 235 eligible patients with OVCFs who underwent VA procedures were recruited from two independent institutions and categorized into three groups, including training set (n = 138), internal validation set (n = 59), and external validation set (n = 38). In the training set, radiomics features were computationally retrieved from L1 or adjacent vertebral body (T12 or L2) on T1-w MRI images, and a radiomics signature was constructed using the least absolute shrinkage and selection operator algorithm (LASSO). Predictive radiomics signature and clinical factors were fitted into two final prediction models using the random survival forest (RSF) algorithm or COX proportional hazard (CPH) analysis. Independent internal and external validation sets were used to validate the prediction models.

RESULTS

The two prediction models were integrated with radiomics signature and intravertebral cleft (IVC). The RSF model with C-indices of 0.763, 0.773, and 0.731 and time-dependent AUC (2 years) of 0.855, 0.907, and 0.839 (p < 0.001 for all) was found to be better predictive than the CPH model in training, internal and external validation sets. The RSF model provided better calibration, larger net benefits (determined by decision curve analysis), and lower prediction error (time-dependent brier score of 0.156, 0.151, and 0.146, respectively) than the CPH model.

CONCLUSIONS

The integrated RSF model showed the potential to predict imminent NVFs following vertebral augmentation, which will aid in postoperative follow-up and treatment.

Vertebral refracture after percutaneous vertebroplasty for osteoporotic vertebral compression fractures with and without brace wearing: A retrospective study of 300 patients

Background

The aim of the study was to examine the clinical incidence rate of vertebral body fractures after percutaneous vertebroplasty (PVP) with and without brace wearing and provide a new guiding ideology for preventing vertebral fractures after clinical surgeries.

Methods

The retrospective analysis included 100 outpatients who underwent PVP between January 2017 and December 2018 without bracing after PVP surgeries (non-brace-wearing group). In total, 100 patients were paired into the rigid brace group and 100 patients were paired into the soft braces group according to propensity score matching. Seven independent variables were used in the soft and rigid brace group: age, sex, body mass index (BMI), visual analog scale (VAS), Oswestry Disability Index (ODI), and Cobb angle. The VAS, ODI, and Japanese Orthopaedic Association (JOA) scores were recorded preoperatively on the second day, after 1 month, after 3 months, and during the last follow-up postoperatively. We recorded the incidence of vertebral refracture in each of the three groups of patients and evaluated the effect of braces on postoperative fractures based on the ODI, VAS, and JOA scores.

Results

All patients were followed up for 8-24 months (mean 22.4 months). Compared with the preoperative values, the age, sex, BMI, bone density, ODI, VAS, and Cobb angle between refracture and non-refracture were not statistically significant. The VAS, ODI, and JOA scores significantly increased in the brace-wearing group compared with those of the non-brace-wearing group (p < 0.05). The incidence of vertebral refracture in the brace-wearing group was lower than that in the non-brace-wearing group, between which there was a significant difference (p < 0.05). Three months postoperatively, the JOA score of the soft brace group was significantly higher than that of the rigid brace group (p < 0.05). During the last follow-up, it was found that there was no difference in the VAS score, the incidence of refracture, or ODI between the soft brace group and the rigid brace group (p > 0.05). The improvement in the JOA score of the soft brace group was better than that of the rigid brace group, between which there was a significant difference (p < 0.05).

Conclusion

Braces can improve the prognosis of quality of life and postoperative subjective perception, whose presence can relieve postoperative residual pains. In contrast, patients can have a better medical experience wearing a soft brace.

Efficacy of Recombinant Human Parathyroid Hormone versus Vertebral Augmentation Procedure on Patients with Acute Osteoporotic Vertebral Compression Fracture

OBJECTIVE

Although widely used in clinical practice, vertebral augmentation procedure (VAP) for osteoporotic vertebral compression fracture (OVCF) is not supported. Recently, the effect of recombinant human parathyroid hormone (1-34) (rhPTH) has been paid great attention for its efficacy in anti-osteoporosis and bone union. This study aims to explore the outcome of rhPTH on acute OVCF and compare it with VAP to clarify its therapeutic advantages.

METHODS

The retrospective study comprised 71 acute OVCF patients from January 2015 to March 2020: 22 received rhPTH treatment (rhPTH group) and 49 underwent VAP (VAP group). The rhPTH group was 15 women and seven men with an average of 76.18 years, and the VAP group were 35 women and 14 men with an average of 73.63 years. The thoracic/lumbar vertebrae were 14/8 in the rhPTH group and 29/20 in the VAP group. The average follow-up period was 14.05 months in the rhPTH group and 13.82 months in the VAP group. The two groups were assessed regarding the visual analog score (VAS), Oswestry Disability Index (ODI), OVCF bone union, bone mineral density (BMD), kyphotic angle (KA), anterior and posterior border height (ABH and PBH, respectively), adverse events and the health-related quality of life assessed by short form-36 health survey scores (SF-36). Categorical variables were analyzed by chi-square test and continuous variables between groups were analyzed by independent samples t-test or Mann-Whitney U test according to the normality.

RESULTS

During the follow-up, the VAS was significantly lower in the rhPTH group than in the VAP group at month 3 (0.39 ± 0.6 vs 0.68 ± 0.651) (p = 0.047), month 6 (0.45 ± 0.60 vs 2.18 ± 1.22) (p < 0.001), and month 12 (0.45 ± 0.60 vs 2.43 ± 1.49) (p < 0.001). At month 12, the ODI was significantly lower in the rhPTH group (18.59 ± 3.33%) than in the VAP group (28.93 ± 16.71%) (p < 0.001). Bone bridge was detected on sagittal computed tomography images of all fractured vertebrae in the rhPTH group. The BMD was significantly higher in the rhPTH group (87.66 ± 5.91 Hounsfield units [HU]) than in the VAP group (68.15 ± 11.32HU) (p < 0.001). There were no significant differences in the changes in KA, ABH, and PBH between groups (all p > 0.05). The incidence of new OVCF was significantly lower in the rhPTH group than in the VAP group (p = 0.042). All scores of SF-36 were significantly higher in the rhPTH group than in the VAP group (all p < 0.05).

CONCLUSION

In acute OVCF patients, rhPTH was better than VAP in increasing spinal BMD to promote OVCF healing, reduce new OVCF, and improve back pain, physical ability, and health-related quality of life.

[Cement augmentation in spinal surgery]

Bone cement has been used in spinal surgery for as long as 50 years. In contemporary spinal surgery, cement augmentation of fractured osteoporotic vertebrae in the form of vertebroplasty/kyphoplasty as well as cement augmentation of pedicle screws in instrumented procedures of any etiology are established as standard procedures. Both procedures are very effective, although the benefits of vertebroplasty/kyphoplasty procedures have been controversially discussed in the past. Overall, complications rarely occur. The most relevant complication is cement leakage, which is asymptomatic in the majority of cases but in the worst case might lead to neurological deficits, embolic events and even circulatory collapse. Prevention of cement leakage is therefore crucial. Risk factors for cement leakage and preventive measures are presented in a comprehensive review based on the available literature.

Occurrence of adjacent segment fractures after surgical treatment of an osteoporotic vertebral fracture: a retrospective comparison between two different treatment methods

INTRODUCTION

Osteoporotic vertebral fractures are a major healthcare problem. Vertebral cement augmentation (VCA) is frequently used as a minimally invasive surgical approach to manage symptomatic fractures. However, there is a potential risk of adjacent segment fracture (ASF), which may require second surgery. The addition of transcutaneous screw-fixation with cement augmentation superior and inferior to the fracture [Hybrid transcutaneous screw fixation (HTSF)] might represent an alternative treatment option to reduce the incidence of ASF.

MATERIALS AND METHODS

We retrospectively compared surgery time, hospital stay, intraoperative complication rate and the occurrence of ASF with the need for a surgical treatment in a cohort of 165 consecutive patients receiving either VCA or HTSF in our academic neurosurgical department from 2012 to 2020. The median follow-up was 52.3 weeks in the VCA-group and 51.9 in the HTSF-group.

RESULTS

During the study period, 93 patients underwent VCA, and 72 had HTSF. Of all patients, 113 were females (64 VCA; 49 HTSF) and 52 were males (29 VCA; 23 HTSF). The median age was 77 years in both groups. Median surgery time was 32 min in the VCA-group and 81 min in the HTSF-group (p < 0.0001). No surgery-related complications occurred in the VCA-group with two in the HTSF-group (p = 0.19). ASF was significantly higher in the VCA-group compared to HTSF (24 [26%] vs. 8 [11%] patients; p < 0.02). The proportion of patients requiring additional surgery due to ASF was higher in the VCA-group (13 vs. 6%), but this difference was not statistically significant (p = 0.18). Median hospital stay was 9 days in the VCA-group and 11.5 days in the HTSF-group (p = 0.0001).

CONCLUSIONS

Based on this single-center cohort study, HTSF appears to be a safe and effective option for the treatment of osteoporotic vertebral compression fractures. Surgical time and duration of hospital stay were longer in the HTSF-group, but the rate of ASF was significantly reduced with this approach. Further studies are required to ascertain whether HTSF results in superior long-term outcomes or improved quality of life.

Efficacy and safety of percutaneous vertebroplasty for osteoporotic vertebral compression fractures

Background

Osteoporotic vertebral compression fractures constitute a major concern in elderly population who may not tolerate conservative treatment. Although percutaneous vertebroplasty is an alternative minimally invasive procedure that is commonly used nowadays, there is still debate about its efficacy. The study aim is to provide short term experience about efficacy of vertebroplasty for osteoporotic vertebral fractures.

Methods

Thirty five patients were treated by percutaneous vertebroplasty (the intervention group). The visual analog scale before the intervention (pre VAS), one week after the intervention (post VAS 1), at three months (post VAS 2) after the intervention were compared at each time point with the control group (35 patients). The oswestry disability index before (pre ODI) and three months after the procedure (post ODI) were assessed. The control group received the optimal medical treatment and a regular physiotherapy program for three months.

Results

Both conservative and vertebroplasty group showed significant improvement in the VAS/ODI with time. With vertebroplasty, the improvement is faster and statistically significant compared with conservative group. There were statistically significant differences between both groups concerning post VAS 1, post VAS 2 and post ODI as the P values were 0.00 in all relationships.

Conclusion

Patients with osteoporotic compression fractures who were treated with percutaneous vertebroplasty experienced considerable clinical improvement in comparison with those who received the conservative management.

Impact of Multifidus Muscle Atrophy on the Occurrence of Secondary Symptomatic Adjacent Osteoporotic Vertebral Compression Fractures

To assess the potential influence of multifidus atrophy and fatty degeneration on the incidence of adjacent vertebral compression fractures within one year after the index fracture. In a retrospective cohort study, patients who underwent surgery for an OVCF were identified and baseline characteristics, fracture patterns and the occurrence of secondary adjacent fractures within one year were obtained by chart review. Multifidus muscle atrophy and fatty degeneration were determined on preoperative MRI or CT scans. In this analysis of 191 patients (mean age 77 years, SD 8, 116 female), OF type 3 was the most common type of OVCF (49.2%). Symptomatic adjacent OVCFs within one year after index fracture were observed in 23/191 patients (12%) at mean 12, SD 12 weeks (range 1-42 weeks) postoperatively. The mean multifidus muscle area was 264, SD 53 mm² in patients with an adjacent vertebral fracture and 271, SD 92 mm² in patients without a secondary fracture (p = 0.755). Mean multifidus fatty infiltration was graded Goutallier 2.2, SD 0.6 in patients with an adjacent fracture and Goutallier 2.2, SD 0.7 in patients without an adjacent fracture (p = 0.694). Pre-existing medication with corticosteroids was associated with the occurrence of an adjacent fracture (p = 0.006). Multifidus area and multifidus fatty infiltration had no significant effect on the occurrence of adjacent vertebral fractures within one year after the index fracture. Patients with a pre-existing medication with corticosteroids were more likely to sustain an adjacent fracture.

Development and internal validation of a clinical prediction model for acute adjacent vertebral fracture after vertebral augmentation : the AVA score

AIMS

To develop and internally validate a preoperative clinical prediction model for acute adjacent vertebral fracture (AVF) after vertebral augmentation to support preoperative decision-making, named the after vertebral augmentation (AVA) score.

METHODS

In this prognostic study, a multicentre, retrospective single-level vertebral augmentation cohort of 377 patients from six Japanese hospitals was used to derive an AVF prediction model. Backward stepwise selection (p < 0.05) was used to select preoperative clinical and imaging predictors for acute AVF after vertebral augmentation for up to one month, from 14 predictors. We assigned a score to each selected variable based on the regression coefficient and developed the AVA scoring system. We evaluated sensitivity and specificity for each cut-off, area under the curve (AUC), and calibration as diagnostic performance. Internal validation was conducted using bootstrapping to correct the optimism.

RESULTS

Of the 377 patients used for model derivation, 58 (15%) had an acute AVF postoperatively. The following preoperative measures on multivariable analysis were summarized in the five-point AVA score: intravertebral instability (≥ 5 mm), focal kyphosis (≥ 10°), duration of symptoms (≥ 30 days), intravertebral cleft, and previous history of vertebral fracture. Internal validation showed a mean optimism of 0.019 with a corrected AUC of 0.77. A cut-off of ≤ one point was chosen to classify a low risk of AVF, for which only four of 137 patients (3%) had AVF with 92.5% sensitivity and 45.6% specificity. A cut-off of ≥ four points was chosen to classify a high risk of AVF, for which 22 of 38 (58%) had AVF with 41.5% sensitivity and 94.5% specificity.

CONCLUSION

In this study, the AVA score was found to be a simple preoperative method for the identification of patients at low and high risk of postoperative acute AVF. This model could be applied to individual patients and could aid in the decision-making before vertebral augmentation. Cite this article: Bone Joint J 2022;104-B(1):97-102.

Establishment and validation of a nomogram and web calculator for the risk of new vertebral compression fractures and cement leakage after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fractures

PURPOSE

The aim of this work was to investigate the risk factors for cement leakage and new-onset OVCF after Percutaneous vertebroplasty (PVP) and to develop and validate a clinical prediction model (Nomogram).

METHODS

Patients with Osteoporotic VCF (OVCF) treated with PVP at Liuzhou People's Hospital from June 2016 to June 2018 were reviewed and met the inclusion criteria. Relevant data affecting bone cement leakage and new onset of OVCF were collected. Predictors were screened using univariate and multi-factor logistic analysis to construct Nomogram and web calculators. The consistency of the prediction models was assessed using calibration plots, and their predictive power was assessed by tenfold cross-validation. Clinical value was assessed using Decision curve analysis (DCA) and clinical impact plots.

RESULTS

Higher BMI was associated with lower bone mineral density (BMD). Higher BMI, lower BMD, multiple vertebral fractures, no previous anti-osteoporosis treatment, and steroid use were independent risk factors for new vertebral fractures. Cement injection volume, time to surgery, and multiple vertebral fractures were risk factors for cement leakage after PVP. The development and validation of the Nomogram also demonstrated the predictive ability and clinical value of the model.

CONCLUSIONS

The established Nomogram and web calculator (https://dr-lee.shinyapps.io/RefractureApp/) (https://dr-lee.shinyapps.io/LeakageApp/) can effectively predict the occurrence of cement leakage and new OVCF after PVP.

Systematic Review and Meta-Analysis of 3 Treatment Arms for Vertebral Compression Fractures: A Comparison of Improvement in Pain, Adjacent-Level Fractures, and Quality of Life Between Vertebroplasty, Kyphoplasty, and Nonoperative Management

BACKGROUND

Osteoporotic vertebral fractures (OVFs) have become increasingly common, and previous nonrandomized and randomized controlled trials (RCTs) have compared the effects of cement augmentation versus nonoperative management on the clinical outcome. This meta-analysis focuses on RCTs and the calculated differences between cement augmentation techniques and nonsurgical management in outcome (e.g., pain reduction, adjacent-level fractures, and quality of life [QOL]).

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, and the following scientific search engines were used: MEDLINE, Embase, Cochrane, Web of Science, and Scopus. The inclusion criteria included RCTs that addressed different treatment strategies for OVF. The primary outcome was pain, which was determined by a visual analog scale (VAS) score; the secondary outcomes were the risk of adjacent-level fractures and QOL (as determined by the EuroQol-5 Dimension [EQ-5D] questionnaire, the Oswestry Disability Index [ODI], the Quality of Life Questionnaire of the European Foundation for Osteoporosis [QUALEFFO], and the Roland-Morris Disability Questionnaire [RDQ]). Patients were assigned to 3 groups according to their treatment: vertebroplasty (VP), kyphoplasty (KP), and nonoperative management (NOM). The short-term (weeks), midterm (months), and long-term (>1 year) effects were compared. A random effects model was used to summarize the treatment effect, including I2 for assessing heterogeneity and the revised Cochrane risk-of-bias 2 (RoB 2) tool for assessment of ROB. Funnel plots were used to assess risk of publication bias. The log of the odds ratio (OR) between treatments is reported.

RESULTS

After screening of 1,861 references, 53 underwent full-text analysis and 16 trials (30.2%) were included. Eleven trials (68.8%) compared VP and NOM, 1 (6.3%) compared KP and NOM, and 4 (25.0%) compared KP and VP. Improvement of pain was better by 1.31 points (95% confidence interval [CI], 0.41 to 2.21; p < 0.001) after VP when compared with NOM in short-term follow-up. Pain effects were similar after VP and KP (midterm difference of 0.0 points; 95% CI, -0.25 to 0.25). The risk of adjacent-level fractures was not increased after any treatment (log OR, -0.16; 95% CI, -0.83 to 0.5; NOM vs. VP or KP). QOL did not differ significantly between the VP or KP and NOM groups except in the short term when measured by the RDQ.

CONCLUSIONS

This meta-analysis provides evidence in favor of the surgical treatment of OVFs. Surgery was associated with greater improvement of pain and was unrelated to the development of adjacent-level fractures or QOL. Although improvements in sagittal balance after surgery were poorly documented, surgical treatment may be warranted if pain is a relevant problem.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Restoration of the intravertebral stability in Kümmell's disease following the treatment of severe postmenopausal osteoporosis by 1-34PTH-a retrospective study

Following the 1-34PTH application for conservative treatment of Kümmell's disease, the intravertebral cleft was filled or bridged by the osseous tissue; the radiological evidence of further collapsing was absent. Pain and the neurological disorder were relieved; bone turnover markers, BMD as well as the health-related quality of life were improved.

INTRODUCTION

Kümmell's disease (KD) patients with severe osteoporosis were applied by the 1-34PTH; the fracture union and the increased bone mineral density (BMD) following this treatment were retrospectively reviewed.

METHODS

Twenty-one postmenopausal osteoporosis (PMOP) patients with KD received at least 6 months of 1-34PTH treatment. The medical records, including clinical evaluation symptoms, radiological evaluation for bone union and the stability of intravertebral vacuum cleft (IVC), BMD, and laboratory examination for osteoporosis recovery and health-related quality of life (HRQOL), were reviewed.

RESULTS

From baseline to month 12, visual analog scale decreased from 8.24 ± 0.54 to 1.71 ± 0.56 (P < 0.001) and the modified Japanese Orthopedic Association scores increased from 6.86 ± 1.77 to 10.43 ± 1.29 (P < 0.001). Sagittal CT demonstrated that the IVC was filled or bridged by the osseous tissue in all patients. Within the vertebra, the IVC area (IVCA) decreased from 4.50 ± 2.50 to 0 mm² (P = 0.001) and the mineralized bone area (MBA) increased from 170.91 ± 102.23 to 259.56 ± 98.60 mm² (P < 0.001). The area ratio of IVC to vertebra decreased from 0.97 ± 0.46 to 0% (P < 0.001), and the area ratio of mineral bone to vertebra was increased from 32.85 ± 14.51 to 54.97 ± 14.01% (P < 0.001). The kyphosis angle increment was 3.43 ± 1.80°, and the loss rate of anterior border height was 11.14 ± 4.82%. No differences were found in posterior border height and spinal canal diameter. The PINP, β-CTx, BMD, and Short Form-36 Health Survey scores markedly increased.

CONCLUSIONS

In KD patients with severe PMOP, 1-34PTH treatment could alleviate the clinical evaluation symptoms, facilitate the recovery of the intravertebral stability, ameliorate the BMD, and improve the HRQoL.

Comparison of Percutaneous Kyphoplasty with or without Pedicle Screw Fixation in Osteoporotic Thoracolumbar Vertebral Fractures: A Retrospective Study

Background

Osteoporotic thoracolumbar compression fractures have become a great social burden due to the aging tendency of population. This study is aimed at comparing the clinical and radiological outcomes of percutaneous kyphoplasty with or without pedicle screw fixation in patients with osteoporotic thoracolumbar fractures. Hypothesis. There is a difference in clinical outcomes between percutaneous kyphoplasty with pedicle screw fixation and percutaneous kyphoplasty.

Methods

This retrospective study included 87 patients who received percutaneous kyphoplasty with or without pedicle screw fixation between October 2015 and October 2017 at Ningbo No.6 Hospital and were followed for 2 years. A total of 40 patients received percutaneous kyphoplasty with pedicle screw fixation (PKPF group), and the other 47 patients had percutaneous kyphoplasty only (PKP group). The outcomes were measured using the visual analogue scale (VAS), Oswestry Disability Index (ODI), Cobb angle (CA), and anterior vertebra height rate (AVHr), which were calculated at preoperative admission and each follow-up visit. Complications including postoperative back pain, refracture, and fixation failure were collected from medical records.

Results

There was no significant difference in baseline characteristics or preoperative data between the two groups (p < 0.05) but significantly better improvements in VAS, ODI, CA, and AVHr at 12- and 24-month follow-up visits in the PKPF group compared with those of the PKP group. 23 (48.9%) patients in the PKP group had complications, whereas only 5 (12.5%) patients in the PKPF group presented complications including 2 postoperative back pain and 1 fixation failure (p = 0.04).

Conclusions

PKPF obtained longer correction and better improvement in VAS, ODI, and CA in patients with osteoporotic thoracolumbar vertebral fractures than PKP.

Association Between Bone Cement Augmentation and New Vertebral Fractures in Patients with Osteoporotic Vertebral Compression Fractures: A Systematic Review and Meta-Analysis

PURPOSE

To investigate the association between bone cement augmentation and new vertebral fractures (VF) in patients with osteoporotic vertebral compression fractures (OVCFs).

METHODS

A literature search of PubMed, EMBASE, and the Cochrane Library was conducted from 1987 to December 31, 2020, to identify randomized controlled trials that compared bone cement augmentation with non-bone cement treatments in patients with OVCFs. The clinical incidence of new VF and the risk of new adjacent vertebral fractures (AVF) after treatment were calculated. The indexes of the risk ratio or odds ratio, and 95% confidence intervals were determined with RevMan 5.2 software.

RESULTS

A total of 13 randomized controlled trials involving 1949 participants were included in the final quantitative analysis. There was no significant association between bone cement augmentation and the clinical incidence of new VF during the 6-month and 12-month follow-ups or the whole follow-up period. However, there was a significantly lower clinical incidence of new VF in patients who received bone cement augmentation compared with non-bone cement treatments during 24 months or more of follow-up. Pooled data from the relevant trials demonstrated that the risk of new AVF in bone cement augmentation was significantly higher than that in non-bone cement treatments.

CONCLUSIONS

Although the use of bone cement augmentation in OVCFs significantly increased the risk of new AVF compared with non-bone cement treatments, it was not significantly associated with a higher clinical incidence of new VF.

A meta-analysis of the secondary fractures for osteoporotic vertebral compression fractures after percutaneous vertebroplasty

To identify the risk factors of the secondary fractures for osteoporotic vertebral compression fractures (OVCFs) after percutaneous vertebroplasty (PVP).We conducted a search of relevant articles using Cochrane Library, PubMed, Medline, Science Direct, Embase, the Web of Science and other databases. The time range we retrieved from establishment of the electronic database to November 2017. Gray studies were found in the references of included literature reports. STATA version 11.0 (Stata Corporation, College Station, Texas) was used to analyze the pooled data.Fourteen studies involving 1910 patients, 395 of whom had fracture secondary to the surgery were included in this meta-analysis. The result of meta-analyses showed the risk factors of the secondary fractures for OVCFs after PVP was related to bone mineral density (BMD) [95%CI (-0.650, -0.164), SMD=-0.407, P=.001], cement leakage ((RR=0.596, 95%CI (0.444,0.798), P = .001)), and kyphosis after primary operation ((SMD=0.741, 95%CI (0.449,1.032), P = .000)), but not to gender, age, body mass index, cement volume, thoracolumbar spine, and cement injection approaches.Bone mineral density, cement leakage, and kyphosis after primary operation are the risk factors closely correlative to the secondary fracture after PVP. There have not been enough evidences to support the association between the secondary fracture and gender, age, body mass index, cement volume, thoracolumbar spine, and cement injection approaches.

A Multiscale Finite Element Analysis of Balloon Kyphoplasty to Investigate the Risk of Bone-Cement Separation In Vivo

BACKGROUND

During the past decade there has been a significant increase in the number of vertebral fractures being treated with the balloon kyphoplasty procedure. Although previous investigations have found kyphoplasty to be an effective treatment for reducing patient pain and lowering cement-leakage risk, there have been reports of vertebral recollapse following the procedure. These reports have indicated evidence of in vivo bone-cement separation leading to collapse of the treated vertebra.

METHODS

The following study documents a multiscale analysis capable of evaluating the risk of bone-cement interface separation during lying, standing, and walking activities following balloon kyphoplasty.

RESULTS

Results from the analysis found that instances of reduced cement interlock could initiate both tensile and shear separation of the interface region at up to 7 times the failure threshold during walking or up to 1.9 times the threshold during some cases for standing. Lying prone offered the best protection from interface failure in all cases, with a minimum safety factor of 2.95.

CONCLUSIONS

The results of the multiscale analysis show it is essential for kyphoplasty simulations to take account of the micromechanical behavior of the bone-cement interface to be truly representative of the in vivo situation after the treatment. The results further illustrate the importance of ensuring adequate cement infiltration into the compacted bone periphery during kyphoplasty through a combination of new techniques, tools, and biomaterials in a multifaceted approach to solve this complex challenge.

Vertebral Collapse Prevented Following Teriparatide Treatment in Postmenopausal Kümmell's Disease Patients with Severe Osteoporosis

OBJECTIVE

To compare the preventive effects of teriparatide and alendronate on the progression of vertebral body collapse in postmenopausal single-level Kümmell's disease (KD).

METHODS

From March 2013 to December 2020, the medical records for 53 postmenopausal single-level KD patients who received conservative treatment with teriparatide (25 patients, teriparatide group) or alendronate (28 patients, alendronate group) were retrospectively reviewed. Midsagittal computed tomography (CT) images were analyzed by ImageJ to assess the intravertebral bone formation (mineralized bone) by calculating the ratio of area of intravertebral mineralized bone (AIMB) to the area of fractured vertebral body (AFVB). The changes in radiological parameters of the fractured vertebral body including kyphosis angle (KA), anterior and posterior border heights (ABH and PBH) and spinal canal diameter (SCD), bone turnover biomarkers (BTMs), and bone mineral density (BMD) were analyzed to evaluate the therapeutic effect.

RESULTS

At month 12, the ratio of AIMB to AFVB was significantly greater in teriparatide group (54.28% ± 15.30%) than in alendronate group (35.57% ± 17.61%) (P < 0.001). Sagittal CT substantiated the formation of bone bridge in 16 patients in teriparatide group. No bone bridge was detected in alendronate group. The KA was significantly smaller and the ABH, PBH, and SCD was greater in teriparatide group than in alendronate group (all P < 0.001). The KA increments were significantly smaller in teriparatide group (3.98° ± 1.30°) than in alendronate group (11.43° ± 3.73°) (P < 0.001). The ABH and PBH decrement were significantly lower in teriparatide group (11.96% ± 1.93% and 2.80% ± 2.52%) than in alendronate group (37.04% ± 8.00% and 19.50% ± 8.22%) (both P < 0.001). The BTMs and BMD were significantly greater in the teriparatide group than in the alendronate group. In teriparatide group, KA increment was negatively correlated with the change in PINP (r = -0.781, P < 0.001) and the ratio of AIMB to AFVB (r = -0.592, P = 0.002) from baseline to month 12. The ABH decrement was negatively correlated with the change in PINP (r = -0.612, P = 0.001) and the ratio of AIMB to AFVB (r = -0.806, P < 0.001) from baseline to month 12.

CONCLUSIONS

In postmenopausal single-level KD patients, conservative treatment with teriparatide was better than alendronate at preventing the progressive vertebral collapse.

Resomer C212© in vertebroplasty or kyphoplasty: A feasibility study on artificial bones with biomechanical and thermal evaluation

BACKGROUND

Vertebroplasty and kyphoplasty are now well-established methods for treating compression fractures of vertebral bodies (AO type A) as well as vertebral body metastases [1, 2, 3]. However, polymethylmethacrylate (PMMA) augmented vertebrae show fractures of subsequent vertebral bodies due to the increased stability of the augmented vertebral body [4]. Resorbable cements are currently only used experimentally. Many commercially available resorbable calcium phosphate cements do not exhibit sufficient biomechanical stability to treat vertebral body fractures [5]. Resomer C212© (Evonik Industries AG, Essen, Germany) is a slow resorbable poly-ε-caprolactone that has low melting temperatures and good biomechanical properties.

OBJECTIVE

This is a feasibility study on how the poly-ε-caprolactone Resomer C212© can be used for kypho- or vertebroplasty, what temperatures are used in the argumentation and how differences in load capacity are measurable compared to conventional PMMA cement.

METHODS

23 Sawbones© blocks (7.5 Open Cell Foam, SKU: 1522-09, laminated on both sides, 4 × 4 × 2.9 cm, Sawbones, Vashon Island, USA) were divided into three groups: 7 without augmentation, 8 augmented with PMMA cement Traumacem V+© (DePuy Synthes, West Chester, USA) and 8 augmented with Resomer C212©. Temperature measurements were made in a 37∘C water bath centrally in the block and on the top and bottom plates. This was followed by a maximum load of up to 2000 N using a universal testing machine (Instron E 10000, Instron Industrial Products, Grove City, USA).

RESULTS

In the Resomer C212© test group, the maximum average increase in temperature was 4.15 ± 4.72∘C central, 0.3 ± 0.31∘C at the top and 0.78 ± 1.27∘C at the base. In the cement test group, the average increase in temperature was 9.80 ± 10.65∘C centrally in the test block, 1.50 ± 0.73∘C at the top plate and 1.42 ± 0.66∘C and the base plate. In the axial compression test, the 7 non-kyphoplasted test blocks showed a first loading peak on average at 275.23 ± 80.98 N, a rigidity of 238.47 ± 71.01 N/mm2. In the Traumacem V+© group, the mean peak load was 313.72 ± 46.26 N and rigidity was 353.45 ± 77.23 N/mm2. The Resomer C212© group achieved a peak load of 311.74 ± 52.05 N and a stiffness of 311.30 ± 126.63 N/mm2. A compression to 50% could not be seen in any test block under the load of 2000 N. At 2000 N, Traumacem V+©'s average height reduction was 9.26 ± 2.16 mm and Resomer C212© was 10.93 ± 0.81 mm.

CONCLUSIONS

It has been shown that the application of Resomer C212© in kyphoplasty or vertebroplasty is well feasible. Thermal analysis showed significantly lower temperatures and shorter temperature application in the Resomer C212© group. In the biomechanical load up to 2000 N no significant differences could be observed between the individual groups.

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.

Prophylactic Percutaneous Kyphoplasty Treatment for Nonfractured Vertebral Bodies in Thoracolumbar for Osteoporotic Patients

Purpose

The occurrence of new vertebral compression fractures (VCFs) is a common complication after percutaneous kyphoplasty (PKP). Secondary VCFs after PKP occur predominantly in the thoracolumbar segment (T11 to L2). Prophylactic injections of cement into vertebral bodies in order to reduce new VCFs have rarely been reported. The main purpose of this study was to investigate whether prophylactically injecting cement into a nonfractured vertebral body at the thoracolumbar level (T11-L2) could reduce the occurrence of new VCFs.

Methods

From July 2011 to July 2018, PKP was performed in 86 consecutive patients with osteoporotic vertebral compression fractures (OVCFs) in the thoracolumbar region (T11-L2). All patients selected underwent PKP because of existing OVCFs (nonprophylactic group). Additionally, 78 consecutive patients with fractured vertebrae in the thoracolumbar region (T11-L2) with OVCFs underwent PKP and received prophylactic injections of cement into their nonfractured vertebrae in the thoracolumbar region (T11-L2) (prophylactic group). The visual analog scale (VAS) scores and incidence of new VCFs after PKP were compared between the two groups.

Results

The mean VAS scores improved from 8.00 ± 0.79 preoperatively to 1.62 ± 0.56 at the last follow-up in the nonprophylactic group and improved from 8.17 ± 0.84 to 1.76 ± 0.34 in the prophylactic group (P > 0.05). In the nonprophylactic group, 21 of 86 patients (24.4%) developed new VCFs within one year after PKP, of whom 15 patients (71.4%) developed VCFs within 3 months. In the prophylactic group, 8 of 78 patients (10.3%) developed new VCFs within one year, and 6 of these 8 patients (75%) developed new VCFs within 3 months. The incidence of new VCFs was significantly higher in the nonprophylactic group than that in the prophylactic group at one year (P = 0.018), but there were no statistically significant differences at three months (P = 0.847).

Conclusions

Prophylactic injections of cement into nonfractured (T11-L2) vertebral bodies reduced the incidence of secondary VCFs after PKP in patients with OVCFs, but there was no significant difference in local back pain (VAS) scores between the two groups.

PMMA-Fe3O4 for internal mechanical support and magnetic thermal ablation of bone tumors

Background: Minimally invasive modalities are of great interest in the field of treating bone tumors. However, providing reliable mechanical support and fast killing of tumor cells to achieve rapid recovery of physical function is still challenging in clinical works.

Methods: A material with two functions, mechanical support and magnetic thermal ablation, was developed from Fe₃O₄ nanoparticles (NPs) distributed in a polymethylmethacrylate (PMMA) bone cement. The mechanical properties and efficiency of magnetic field-induced thermal ablation were systematically and successfully evaluated in vitro and ex vivo. CT images and pathological examination were successfully applied to evaluate therapeutic efficacy with a rabbit bone tumor model. Biosafety evaluation was performed with a rabbit in vivo, and a cytotoxicity test was performed in vitro.

Results: An NP content of 6% Fe₃O₄ (PMMA-6% Fe₃O₄, m_Fe: 0.01 g) gave the most suitable performance for in vivo study. At the 56-day follow-up after treatment, bone tumors were ablated without obvious side effects. The pathological examination and new bone formation in CT images clearly illustrate that the bone tumors were completely eliminated. Correspondingly, after treatment, the tendency of bone tumors toward metastasis significantly decreased. Moreover, with well-designed mechanical properties, PMMA-6%Fe₃O₄ implantation endowed tumor-bearing rabbit legs with excellent bio-mimic bone structure and internal support. Biosafety evaluation did not induce an increase or decrease in the immune response, and major functional parameters were all at normal levels.

Conclusion: We have presented a novel, highly efficient and minimally invasive approach for complete bone tumor regression and bone defect repair by magnetic thermal ablation based on PMMA containing Fe₃O₄ NPs; this approach shows excellent heating ability for rabbit VX2 tibial plateau tumor ablation upon exposure to an alternating magnetic field (AMF) and provides mechanical support for bone repair. The new and powerful dual-function implant is a promising minimally invasive agent for the treatment of bone tumors and has good clinical translation potential.

Interventional Techniques to Management of Cancer-Related Pain: Clinical and Critical Aspects

Interventional techniques to manage cancer-related pain may be efficient treatment modalities in patients unresponsive or unable to tolerate systemic opioids. However, indication and selection of the right technique demand knowledge, which is still incipient among clinicians. The present article summarizes the current evidence regarding the five most essential groups of interventional techniques to treat cancer-related pain: Neuraxial analgesia, minimally invasive procedures for vertebral pain, sympathetic blocks for abdominal cancer pain, peripheral nerve blocks, and percutaneous cordotomy. Furthermore, indication, mechanism, drug agents, contraindications, and complications of the main techniques of each group are discussed.

Percutaneous Vertebroplasty Does Not Increase the Incidence of New Fractures in Adjacent and Nonadjacent Vertebral Bodies

STUDY DESIGN

This was a clinical retrospective study.

OBJECTIVES

This retrospective study aimed to investigate the incidence of new vertebral compression fractures (NVCFs) and analyze the risk factors that influence the secondary fractures in adjacent and nonadjacent levels after percutaneous vertebroplasty (PVP) and conservative treatment (CT).

SUMMARY OF BACKGROUND DATA

PVP is an effective procedure to alleviate the pain caused by osteoporotic vertebral compression fractures. NVCFs have been noted as a potential late sequela of the procedure. However, it remains unclear whether NVCFs are due to this augmentation or simply are the result of the natural progression of osteoporosis.

METHODS

A total of 290 patients who had undergone PVP and 270 patients who had undergone CT during the last 4 years were examined. They were followed-up on a monthly basis by telephone for >2 years. They were divided into 2 groups: NVCFs and non-NVCFs. The groups were statistically compared in terms of age, sex, body mass index, initial fracture levels, bone mineral density (BMD) score of the spine, original fracture levels, and new fracture levels.

RESULTS

After a mean follow-up of at least 24 months (range, 24-78 mo), 42 NVCFs occurred in 37 of 290 patients after PVP and 33 NVCFs in 30 of 270 patients after CT. Only BMD was significantly different between the groups. Lower BMD was a significant predictive factor for NVCFs.

CONCLUSIONS

PVP did not increase the incidence of NVCFs, especially those adjacent to the treated vertebrae, following augmentation with PVP compared with CT. The most important risk factor for NVCFs was osteoporosis.

The Efficacy and Safety of Vertebral Augmentation: A Second ASBMR Task Force Report

Vertebral augmentation is among the current standards of care to reduce pain in patients with vertebral fractures (VF), yet a lack of consensus regarding efficacy and safety of percutaneous vertebroplasty and kyphoplasty raises questions on what basis clinicians should choose one therapy over another. Given the lack of consensus in the field, the American Society for Bone and Mineral Research (ASBMR) leadership charged this Task Force to address key questions on the efficacy and safety of vertebral augmentation and other nonpharmacological approaches for the treatment of pain after VF. This report details the findings and recommendations of this Task Force. For patients with acutely painful VF, percutaneous vertebroplasty provides no demonstrable clinically significant benefit over placebo. Results did not differ according to duration of pain. There is also insufficient evidence to support kyphoplasty over nonsurgical management, percutaneous vertebroplasty, vertebral body stenting, or KIVA®. There is limited evidence to determine the risk of incident VF or serious adverse effects (AE) related to either percutaneous vertebroplasty or kyphoplasty. No recommendation can be made about harms, but they cannot be excluded. For patients with painful VF, it is unclear whether spinal bracing improves physical function, disability, or quality of life. Exercise may improve mobility and may reduce pain and fear of falling but does not reduce falls or fractures in individuals with VF. General and intervention-specific research recommendations stress the need to reduce study bias and address methodological flaws in study design and data collection. This includes the need for larger sample sizes, inclusion of a placebo control, more data on serious AE, and more research on nonpharmacologic interventions. Routine use of vertebral augmentation is not supported by current evidence. When it is offered, patients should be fully informed about the evidence. Anti-osteoporotic medications reduce the risk of subsequent vertebral fractures by 40-70%. © 2018 American Society for Bone and Mineral Research.

Effect of Teriparatide on Subsequent Vertebral Fractures after Instrumented Fusion Surgery for Osteoporotic Vertebral Fractures with Neurological Deficits

STUDY DESIGN

Retrospective case review.

PURPOSE

To assess the incidence and effect of teriparatide (TP) on subsequent vertebral fractures following a long-instrumented fusion surgery for osteoporotic vertebral fractures (OVFs).

OVERVIEW OF LITERATURE

TP treatment may be a useful strategy for patients with OVFs treated with a long-instrumented surgery.

METHODS

Overall, 47 patients who underwent long-instrumented fusion surgery (≥3 levels) for OVFs with neurological deficits between 2010 and 2013 were enrolled. The mean age of the subjects was 76 years; the study population comprised 20 males and 27 females. The mean follow-up duration was 23 months. The average of fused vertebrae was 4.9. TP was used for 19 patients who comprised the TP group. The incidence of subsequent VFs was estimated with Kaplan-Meier analyses and compared between the TP and non-TP groups using the log-rank test. Risk factors were evaluated using a Cox proportional hazards model.

RESULTS

A total of 38% (18/47 cases) of the subjects were identified with subsequent VFs. There were no significant differences in the age, sex, fused levels, presence of prevalent fractures, and correction loss of the two groups. The occurrence of subsequent VFs was lower in the TP group than in the non-TP group (16% vs. 54%, p=0.014). The log-rank test revealed that the TP treatment significantly reduced the risk of subsequent VFs (p=0.048). A Cox proportional hazards model revealed that preoperative TP treatment is only a protective factor of subsequent VFs after instrumented fusion surgery for OVFs (hazard ratio, 0.281; p=0.047).

CONCLUSIONS

In this retrospective study, pre- and postoperative TP treatment significantly reduced the incidence of subsequent VFs after instrumented fusion surgery for OVFs. A prospective randomized study is warranted to determine the efficacy of TP treatments.

Percutaneous vertebroplasty for osteoporotic vertebral compression fracture

BACKGROUND

Percutaneous vertebroplasty remains widely used to treat osteoporotic vertebral fractures although our 2015 Cochrane review did not support its role in routine practice.

OBJECTIVES

To update the available evidence of the benefits and harms of vertebroplasty for treatment of osteoporotic vertebral fractures.

SEARCH METHODS

We updated the search of CENTRAL, MEDLINE and Embase and trial registries to 15 November 2017.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) of adults with painful osteoporotic vertebral fractures, comparing vertebroplasty with placebo (sham), usual care, or another intervention. As it is least prone to bias, vertebroplasty compared with placebo was the primary comparison. Major outcomes were mean overall pain, disability, disease-specific and overall health-related quality of life, patient-reported treatment success, new symptomatic vertebral fractures and number of other serious adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodologic procedures expected by Cochrane.

MAIN RESULTS

Twenty-one trials were included: five compared vertebroplasty with placebo (541 randomised participants), eight with usual care (1136 randomised participants), seven with kyphoplasty (968 randomised participants) and one compared vertebroplasty with facet joint glucocorticoid injection (217 randomised participants). Trial size varied from 46 to 404 participants, most participants were female, mean age ranged between 62.6 and 81 years, and mean symptom duration varied from a week to more than six months.Four placebo-controlled trials were at low risk of bias and one was possibly susceptible to performance and detection bias. Other trials were at risk of bias for several criteria, most notably due to lack of participant and personnel blinding.Compared with placebo, high- to moderate-quality evidence from five trials indicates that vertebroplasty provides no clinically important benefits with respect to pain, disability, disease-specific or overall quality of life or treatment success at one month. Evidence for quality of life and treatment success was downgraded due to possible imprecision. Evidence was not downgraded for potential publication bias as only one placebo-controlled trial remains unreported. Mean pain (on a scale zero to 10, higher scores indicate more pain) was five points with placebo and 0.7 points better (0.3 better to 1.2 better) with vertebroplasty, an absolute pain reduction of 7% (3% better to 12% better, minimal clinical important difference is 15%) and relative reduction of 10% (4% better to 17% better) (five trials, 535 participants). Mean disability measured by the Roland-Morris Disability Questionnaire (scale range zero to 23, higher scores indicate worse disability) was 14.2 points in the placebo group and 1.5 points better (0.4 better to 2.6 better) in the vertebroplasty group, absolute improvement 7% (2% to 11% better), relative improvement 9% better (2% to 15% better) (four trials, 472 participants).Disease-specific quality of life measured by the Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO) (scale zero to 100, higher scores indicating worse quality of life) was 62 points in the placebo group and 2.3 points better (1.4 points worse to 6.7 points better), an absolute imrovement of 2% (1% worse to 6% better); relative improvement 4% better (2% worse to 10% better) (three trials, 351 participants). Overall quality of life (European Quality of Life (EQ5D), zero = death to 1 = perfect health, higher scores indicate greater quality of life) was 0.38 points in the placebo group and 0.05 points better (0.01 better to 0.09 better) in the vertebroplasty group, absolute improvement: 5% (1% to 9% better), relative improvement: 18% (4% to 32% better) (three trials, 285 participants). In one trial (78 participants), 9/40 (or 225 per 1000) people perceived that treatment was successful in the placebo group compared with 12/38 (or 315 per 1000; 95% CI 150 to 664) in the vertebroplasty group, RR 1.40 (95% CI 0.67 to 2.95), absolute difference: 9% more reported success (11% fewer to 29% more); relative change: 40% more reported success (33% fewer to 195% more).Low-quality evidence (downgraded due to imprecision and potential for bias from the usual-care controlled trials) indicates uncertainty around the risk estimates of harms with vertebroplasty. The incidence of new symptomatic vertebral fractures (from six trials) was 48/418 (95 per 1000; range 34 to 264)) in the vertebroplasty group compared with 31/422 (73 per 1000) in the control group; RR 1.29 (95% CI 0.46 to 3.62)). The incidence of other serious adverse events (five trials) was 16/408 (34 per 1000, range 18 to 62) in the vertebroplasty group compared with 23/413 (56 per 1000) in the control group; RR 0.61 (95% CI 0.33 to 1.10). Notably, serious adverse events reported with vertebroplasty included osteomyelitis, cord compression, thecal sac injury and respiratory failure.Our subgroup analyses indicate that the effects did not differ according to duration of pain (acute versus subacute). Including data from the eight trials that compared vertebroplasty with usual care in a sensitivity analyses altered the primary results, with all combined analyses displaying considerable heterogeneity.

AUTHORS' CONCLUSIONS

We found high- to moderate-quality evidence that vertebroplasty has no important benefit in terms of pain, disability, quality of life or treatment success in the treatment of acute or subacute osteoporotic vertebral fractures in routine practice when compared with a sham procedure. Results were consistent across the studies irrespective of the average duration of pain.Sensitivity analyses confirmed that open trials comparing vertebroplasty with usual care are likely to have overestimated any benefit of vertebroplasty. Correcting for these biases would likely drive any benefits observed with vertebroplasty towards the null, in keeping with findings from the placebo-controlled trials.Numerous serious adverse events have been observed following vertebroplasty. However due to the small number of events, we cannot be certain about whether or not vertebroplasty results in a clinically important increased risk of new symptomatic vertebral fractures and/or other serious adverse events. Patients should be informed about both the high- to moderate-quality evidence that shows no important benefit of vertebroplasty and its potential for harm.

Percutaneous Vertebral Augmentation Techniques in Osteoporotic and Traumatic Fractures

Percutaneous vertebral augmentation/consolidation techniques are varied. These are vertebroplasty, kyphoplasty, and several methods with percutaneous introduction of an implant (associated or not with cement injection). They are proposed in painful osteoporotic vertebral fractures and traumatic fractures. The objectives are to consolidate the fracture and, if possible, to restore the height of the vertebral body to reduce vertebral and regional kyphosis. Stabilization of the fracture leads to a reduction in pain and thus restores the spinal support function as quickly as possible, which is particularly important in the elderly. The effectiveness of these interventions on fracture pain was challenged once by two randomized trials comparing vertebroplasty to a sham intervention. Since then, many other randomized studies in support of vertebroplasty efficacy have been published. International recommendations reserve vertebroplasty for medical treatment failures on pain, but earlier positioning may be debatable if the objective is to limit kyphotic deformity or even reexpand the vertebral body. Recent data suggest that in osteoporotic fracture, the degree of kyphosis reduction achieved by kyphoplasty and percutaneous implant techniques, compared with vertebroplasty, is not sufficient to justify the additional cost and the use of a somewhat longer and traumatic procedure. In young patients with acute traumatic fractures and a significant kyphotic angle, kyphoplasty and percutaneous implant techniques are preferred to vertebroplasty, as in these cases a deformity reduction has a significant positive impact on the clinical outcome.

Vertebral Augmentation can Induce Early Signs of Degeneration in the Adjacent Intervertebral Disc: Evidence from a Rabbit Model

STUDY DESIGN

An experimental study.

OBJECTIVE

The aim of this study was to determine the effect of polymethylmethacrylate (PMMA) augmentation on the adjacent disc.

SUMMARY OF BACKGROUND DATA

Vertebral augmentation with PMMA reportedly may predispose the adjacent vertebra to fracture. The influence of PMMA augmentation on the adjacent disc, however, remains unclear.

METHODS

Using a retroperitoneal approach, PMMA augmentation was performed for 23 rabbits. For each animal, at least one vertebra was augmented with 0.2 to 0.3 mL PMMA. The disc adjacent to the augmented vertebra and a proximal control disc were studied using magnetic resonance (MR) imaging, histological and molecular level evaluation at 1, 3, and 6 months postoperatively. Marrow contact channels in the endplate were quantified in histological slices and number of invalid channels (those without erythrocytes inside) was rated. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) was performed to determine disc cell apoptosis.

RESULTS

On MR images, the signal and height of the adjacent disc did not change 6 months after vertebral augmentation. Histological scores of the adjacent disc increased over time, particularly for the nucleus pulposus. The adjacent disc had greater nucleus degeneration score than the control disc at 3 months (5.7 vs. 4.5, P < 0.01) and 6 months (6.9 vs. 4.4, P < 0.001). There were more invalid marrow contact channels in the endplate of augmented vertebra than the control (43.3% vs. 11.1%, P < 0.01). mRNA of ADAMTS-5, MMP-13, HIF-1α, and caspase-3 were significantly upregulated in the adjacent disc at 3 and 6 months (P < 0.05 for all). In addition, there were more TUNEL-positive cells in the adjacent disc than in the control disc (43.4% vs. 24.0%, P < 0.05) at 6 months postoperatively.

CONCLUSION

Vertebral augmentation can induce early degenerative signs in the adjacent disc, which may be due to impaired nutrient supply to the disc.

LEVEL OF EVIDENCE

N/A.

Single-level vertebral kyphoplasty is not associated with an increased risk of symptomatic secondary adjacent osteoporotic vertebral compression fractures: a matched case-control analysis

This matched case-control study compared the rate of symptomatic adjacent-level vertebral compression fractures (VCF) within 1 year in patients operatively treated with kyphoplasty to a control group of non-operatively treated VCFs. The adjacent-level fracture rate did not show a significant difference between groups.

PURPOSE

To compare the rate of new symptomatic adjacent-level fractures within 1 year after an isolated osteoporotic vertebral compression fracture (VCF) treated by either kyphoplasty or non-operative treatment.

METHODS

Patients aged ≥ 50 years with an isolated, fresh, and symptomatic osteoporotic VCF who were treated by kyphoplasty were compared to patients of similar age, gender, vertebral segment, and bone mineral density who were treated non-operatively (n = 98). A matched case-control analysis was conducted by retrospective chart review, and the rate of new adjacent-level symptomatic vertebral fractures, defined as occurring within two segments of the index fracture, within the first year was determined.

RESULTS

Ninety-eight patients (66 female, aged 73.5, SD 9.7 years) were analyzed in this matched case-control study. The adjacent fracture rate within 1 year was not different between the kyphoplasty group and the non-operative group (20.4 vs 18.4%; McNemar, p = 1.0). The time to a new adjacent fracture after the index fracture was significantly shorter in the kyphoplasty (7, SD 8 weeks) versus non-operative group (22, SD 13 weeks).

CONCLUSIONS

Patients with osteoporotic VCFs treated with kyphoplasty did not show an increased rate of additional symptomatic adjacent-level VCFs when compared to a non-operative control group matched for age, gender, fracture level, and bone mineral density.

LEVEL OF EVIDENCE

Level III.

Vertebral Fractures Following Denosumab Discontinuation in Patients with Prolonged Exposure to Bisphosphonates

Denosumab (DMAB) efficacy for treatment of osteoporosis was demonstrated in a pivotal trial with a reduction in vertebral and hip fractures during 3 years, and fracture risk reduction was sustained up to 10 years in an extension study. DMAB causes potent yet reversible inhibition of bone resorption. Bone density declines rapidly upon discontinuation and bone turnover markers increase above baseline in a rebound fashion. Spontaneous multiple vertebral fractures after DMAB discontinuation were recently reported. Prior treatment with bisphosphonates (BP) was postulated to decrease the risk for this alarming phenomenon. We aimed to describe our experience of fractures following DMAB withdrawal with special attention to past history of osteoporosis treatment. A phone survey of physicians engaged in bone metabolism from nine hospitals in Israel was performed. Clinical data of the patients presenting with vertebral fractures upon DMAB discontinuation were summarized and compared to the previously published cases. Nine elderly (74.2 ± 5.3 years) female patients were identified. Most patients had a prolonged prior exposure to BP (7.4 ± 3.2 years). All but one sustained osteoporotic fractures prior to DMAB initiation and their FRAX scores were high. Thirty-six vertebral fractures were identified in nine patients. Eight patients presented with multiple fractures, and most fractures were spontaneous. In line with the previous reports, the timing and severity of the fractures raise concern of DMAB discontinuation effect. Prolonged BP exposure in most of our patients challenges the protective effect hypothesis. Care providers, patients, and regulatory authorities should be aware of the possible risk of DMAB treatment interruption.

Cement Distribution Patterns Are Associated with Recompression in Cemented Vertebrae After Percutaneous Vertebroplasty: A Retrospective Study

OBJECTIVE

To reevaluate the cement distribution patterns and further investigate associations between cement distribution patterns and the occurrence rates of recompression in cemented vertebrae after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures.

METHODS

Two hundred twenty-four patients with a mean age of 71.9 years were enrolled and treated with single-level PVP between June 2012 and July 2015. The mean follow-up time was 16.5 months. Data from medical records and radiographs were collected and analyzed. Cement distribution patterns were divided into 4 cement distribution patterns extending from the traditional 2 patterns: interlocked solid pattern (LS) and uninterlocked solid pattern (ULS); contiguous trabecular pattern (CT) and discontiguous trabecular pattern (DCT). Differences in treatment efficacy and the occurrence rates of recompression in cemented vertebrae were compared for both groups using the Wilcoxon rank sum test and chi-squared test.

RESULTS

Thirty-seven patients who underwent PVP developed recompression in cemented vertebrae. Recompression in cemented vertebrae was significantly more frequent in the ULS and DCT groups than in the LS and CT groups (P < 0.05 or 0.001), with the Visual Analogue Scale score at the time of final follow-up was also significantly higher in the ULS and DCT groups (P < 0.001).

CONCLUSIONS

Significant associations were found between cement distribution patterns and recompression in cemented vertebrae, which affected the clinical outcome in patients after PVP. A higher incidence of recompression in cemented vertebrae was seen in patients with treated vertebrae exhibiting ULS pattern or DCT pattern.

Glass -polyalkenoate cement: An alternative material for kyphoplasty in osteoporotic vertebral compression fractures - An ex vivo study

Adjacent vertebral body fracture is described as a risk after vertebroplasty and kyphoplasty. It may be true that this phenomenon is caused precisely because of the frequently used polymethylmethacrylate cement (PMMA), which shows a higher level of stiffness than bone material and may ultimately lead to shifting stress levels within the entire spine. The goal of the present study was to evaluate and compare the pressure distribution in the endplate of human vertebrae after kyphoplasty with PMMA and aluminum-free glass-polyalkenoate cement (gpc). For the present study, 8 fresh frozen human cadaveric vertebral bodies from the thoracolumbar junction were used. All vertebrae were augmented transpedicularly on one side with gpc and on the other side with PMMA. A loading of 600 N, 800 N and 1000 N was applied. In the data processing an individual region of interest (roi) was generated for each vertebra. The following parameters were determined for each roi: maximum force [N], maximum pressure [kPa], mean pressure [kPa], roi area [cm²]. We found significantly higher mean pressure values in the areas of the vertebrae augmented with PMMA, compared to the ones after augmentation with gpc (p = 0.012) when applying 1000 N. In the groups with lower forces there were no statistical relevant differences. The pressure distribution shows an advantage for gpc. A material, which does not create load concentration onto the cranial and caudal vertebral surface, could have major advantages concerning the risk of adjacent vertebral fractures. Thus the results of the 1000 N loading protocol suggest gpc being a possible alternative to ordinary PMMA cement, regarding its influence on stiffness in kyphoplasty. These and other general aspects like incorporation should be addressed and elaborated more detailed in further studies.

Percutaneous vertebroplasty for osteoporotic vertebral compression fracture

BACKGROUND

Percutaneous vertebroplasty remains widely used to treat osteoporotic vertebral fractures although our 2015 Cochrane review did not support its role in routine practice.

OBJECTIVES

To update the available evidence of the benefits and harms of vertebroplasty for treatment of osteoporotic vertebral fractures.

SEARCH METHODS

We updated the search of CENTRAL, MEDLINE and Embase and trial registries to 15 November 2017.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) of adults with painful osteoporotic vertebral fractures, comparing vertebroplasty with placebo (sham), usual care, or another intervention. As it is least prone to bias, vertebroplasty compared with placebo was the primary comparison. Major outcomes were mean overall pain, disability, disease-specific and overall health-related quality of life, patient-reported treatment success, new symptomatic vertebral fractures and number of other serious adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodologic procedures expected by Cochrane.

MAIN RESULTS

Twenty-one trials were included: five compared vertebroplasty with placebo (541 randomised participants), eight with usual care (1136 randomised participants), seven with kyphoplasty (968 randomised participants) and one compared vertebroplasty with facet joint glucocorticoid injection (217 randomised participants). Trial size varied from 46 to 404 participants, most participants were female, mean age ranged between 62.6 and 81 years, and mean symptom duration varied from a week to more than six months.Three placebo-controlled trials were at low risk of bias and two were possibly susceptible to performance and detection bias. Other trials were at risk of bias for several criteria, most notably due to lack of participant and personnel blinding.Compared with placebo, high- to moderate-quality evidence from five trials (one with incomplete data reported) indicates that vertebroplasty provides no clinically important benefits with respect to pain, disability, disease-specific or overall quality of life or treatment success at one month. Evidence for quality of life and treatment success was downgraded due to possible imprecision. Evidence was not downgraded for potential publication bias as only one placebo-controlled trial remains unreported. Mean pain (on a scale zero to 10, higher scores indicate more pain) was five points with placebo and 0.6 points better (0.2 better to 1 better) with vertebroplasty, an absolute pain reduction of 6% (2% better to 10% better, minimal clinical important difference is 15%) and relative reduction of 9% (3% better to14% better) (five trials, 535 participants). Mean disability measured by the Roland-Morris Disability Questionnaire (scale range zero to 23, higher scores indicate worse disability) was 14.2 points in the placebo group and 1.7 points better (0.3 better to 3.1 better) in the vertebroplasty group, absolute improvement 7% (1% to 14% better), relative improvement 10% better (3% to 18% better) (three trials, 296 participants).Disease-specific quality of life measured by the Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO) (scale zero to 100, higher scores indicating worse quality of life) was 62 points in the placebo group and 2.75 points (3.53 worse to 9.02 better) in the vertebroplasty group, absolute change: 3% better (4% worse to 9% better), relative change: 5% better (6% worse to 15% better (two trials, 175 participants). Overall quality of life (European Quality of Life (EQ5D), zero = death to 1 = perfect health, higher scores indicate greater quality of life) was 0.38 points in the placebo group and 0.05 points better (0.01 better to 0.09 better) in the vertebroplasty group, absolute improvement: 5% (1% to 9% better), relative improvement: 18% (4% to 32% better) (three trials, 285 participants). In one trial (78 participants), 9/40 (or 225 per 1000) people perceived that treatment was successful in the placebo group compared with 12/38 (or 315 per 1000; 95% CI 150 to 664) in the vertebroplasty group, RR 1.40 (95% CI 0.67 to 2.95), absolute difference: 9% more reported success (11% fewer to 29% more); relative change: 40% more reported success (33% fewer to 195% more).Moderate-quality evidence (low number of events) from seven trials (four placebo, three usual care, 1020 participants), up to 24 months follow-up, indicates we are uncertain whether vertebroplasty increases the risk of new symptomatic vertebral fractures (70/509 (or 130 per 1000; range 60 to 247) observed in the vertebroplasty group compared with 59/511 (120 per 1000) in the control group; RR 1.08 (95% CI 0.62 to 1.87)).Similarly, moderate-quality evidence (low number of events) from five trials (three placebo, two usual care, 821 participants), indicates uncertainty around the risk of other serious adverse events (18/408 or 76 per 1000, range 6 to 156) in the vertebroplasty group compared with 26/413 (or 106 per 1000) in the control group; RR 0.64 (95% CI 0.36 to 1.12). Notably, serious adverse events reported with vertebroplasty included osteomyelitis, cord compression, thecal sac injury and respiratory failure.Our subgroup analyses indicate that the effects did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks. Including data from the eight trials that compared vertebroplasty with usual care in a sensitivity analyses altered the primary results, with all combined analyses displaying considerable heterogeneity.

AUTHORS' CONCLUSIONS

Based upon high- to moderate-quality evidence, our updated review does not support a role for vertebroplasty for treating acute or subacute osteoporotic vertebral fractures in routine practice. We found no demonstrable clinically important benefits compared with placebo (sham procedure) and subgroup analyses indicated that the results did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks.Sensitivity analyses confirmed that open trials comparing vertebroplasty with usual care are likely to have overestimated any benefit of vertebroplasty. Correcting for these biases would likely drive any benefits observed with vertebroplasty towards the null, in keeping with findings from the placebo-controlled trials.Numerous serious adverse events have been observed following vertebroplasty. However due to the small number of events, we cannot be certain about whether or not vertebroplasty results in a clinically important increased risk of new symptomatic vertebral fractures and/or other serious adverse events. Patients should be informed about both the high- to moderate-quality evidence that shows no important benefit of vertebroplasty and its potential for harm.

Risk factor analysis for re-collapse of cemented vertebrae after percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP)

PURPOSE

Re-collapse of cemented vertebrae occasionally occurs after percutaneous augmentation. However, the potential risks still remain unclear. Several articles have reported some possible risk factors which were not consistent or comprehensive. This study aimed to make a retrospective review on patients with osteoporotic vertebral compression fracture (OVCF) after percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) and to further analyse the risk factors for treated vertebral refracture.

METHODS

All patients receiving the PKP/PVP with bilateral approach were retrospectively reviewed from January 2014 to January 2016, among whom 230 patients with single level augmentation (30 in refracture group and 200 in the non-refracture group) were enrolled according to inclusion criteria. The following covariates were reviewed: gender, age, height, weight, body mass index (BMI), bone mineral density (BMD), serum bone turnover markers, surgical parameters including approach, cement volume, anterior height, and Cobb angle restoration. Binary logistic regression analysis was used to determine the relative risk of re-collapse of cemented vertebrae.

RESULTS

Regarding the patient data, weight, BMI, and BMD were of statistical significance in refracture group (P < 0.01), among which only low BMD was a risk factor to cemented vertebral re-collapse (P = 0.022, OR = 4.197). In respect of surgical variables, the better restoration of anterior height and Cobb angle was found in refracture group (P < 0.05), both of which might increase the refracture risk but not be risk factors (P = 0.065, OR = 0.891, and P = 0.937, OR = 0.996, respectively). Besides, less injected cement (3.30 ± 0.84 ml vs 4.46 ± 1.10 ml, P = 0.000, OR = 19.433) and PKP (P = 0.007, OR = 13.332) significantly boosted the potential risk of refracture (P < 0.001).

CONCLUSION

Patients with low BMD, or undergoing PKP, or receiving a low volume of injected cement might have a high risk of re-collapse in surgical vertebrae.

An injectable, biodegradable calcium phosphate cement containing poly lactic-co-glycolic acid as a bone substitute in ex vivo human vertebral compression fracture and rabbit bone defect models

Purpose/Aim of the study: To evaluate the biomechanical characteristics and biocompatibility of an injectable, biodegradable calcium phosphate cement (CPC) containing poly lactic-co-glycolic acid (PLGA).

MATERIALS AND METHODS

A vertebral compression fracture model was established using 20 human cadaveric vertebrae (T11-L3) divided into CPC/PLGA composite versus PMMA groups for biomechanical testing. In addition, 35 New Zealand rabbits were used to evaluate biodegradability and osteoconductive properties of CPC/PLGA using a bone defect model. In vitro cytotoxicity was evaluated by culturing with L929 cells.

RESULTS

The CPC/PLGA composite effectively restored vertebral biomechanical properties. Compared with controls, the maximum load and compression strength of the CPC/PLGA group were lower, and stiffness was lower after kyphoplasty (all p <.05). Degradation was much slower in the control CPC compared with CPC/PLGA group. The bone tissue percentage in the CPC/PLGA group (44.9 ± 23.7%) was significantly higher compared with control CPC group (25.7 ± 10.9%) (p <.05). The viability of cells cultured on CPC/PLGA was greater than 70% compared with the blanks.

CONCLUSIONS

Our biodegradable CPC/PLGA composite showed good biomechanical properties, cytocompatibility, and osteoconductivity and may represent an ideal bone substitute for future applications.

Use of corticosteroids is not associated with repeated vertebroplasty or kyphoplasty within one year after the surgery in patient older than 50 years

OBJECTIVE

The aim of this study was to investigate whether corticosteroid use increases the incidence of repeated PVP or kyphoplasty patients older than 50 years.

METHODS

This study enrolled the data of 2,753 eligible patients from the Taiwan National Health Insurance Research Database who were exposed to systemic corticosteroids for at least 3 months during the first year preceding the first PVP or kyphoplasty. These steroid users were matched 1:1 in age, sex, and the index date of surgery with non-user controls during the enrollment period. All patients were followed for 1 year after the first PVP or kyphoplasty. The incidence of repeated PVP or kyphoplasty was compared between the steroid users and controls. A Cox proportional hazards model was developed to account for multiple confounding factors.

RESULTS

The number of patients receiving repeated PVP or kyphoplasty was 233 (8.46%) and 205 (7.45%) in the corticosteroid and control groups, respectively. The Cox proportional hazards model revealed no association between corticosteroid use and repeated PVP or kyphoplasty.

CONCLUSIONS

Systemic corticosteroid use for longer than 3 months is not associated with repeated PVP or kyphoplasty within one year of surgery in patient older than 50 years old.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Modification of PMMA vertebroplasty cement for reduced stiffness by addition of normal saline: a material properties evaluation

PURPOSE

Vertebral augmentation is an established treatment for patients with pathological vertebral compression fractures. These procedures typically employ a PMMA-based bone cement, which possesses a high compressive stiffness. Because of the increased risk of subsequent fractures after vertebral augmentations, there is a desire for reducing this stiffness. The goal of our study was to examine the influence of adding isotonic saline on the biomechanical properties of PMMA vertebroplasty cement.

METHODS

A PMMA-based vertebroplasty cement was prepared according to the manufacturer's recommendations after which isotonic saline was mixed into the cement at 10, 20, and 30% (volume:volume). Testing bodies were cast, and compression and bending tests were performed. Fracture surfaces were studied using SEM. Measurements of injectability, setting temperature, and radioopacity were also performed.

RESULTS

The addition of saline solution (of up to vol-30%) led to a pronounced reduction in the compression modulus of the cement from 3409 ± 312 to 1131 ± 127 MPa. In parallel, maximal compression strength was reduced from 86 ± 4 to 33 ± 3 MPa and bending strength from 40 ± 4 to 24 ± 3 MPa. The differences regarding injectability, setting temperature, and radioopacity were small and probably of no clinical relevance.

CONCLUSIONS

The compressive stiffness of PMMA-based vertebroplasty cement can be reduced to almost a third by the addition of saline. The probable explanation is an increase in microporosity. Future simulator experiments will show whether the achieved reduction in stiffness is large enough to reduce the rate of subsequent vertebral fractures.

Does vertebral augmentation lead to an increasing incidence of adjacent vertebral failure? A systematic review and meta-analysis

BACKGROUND

The aim of the present study was to evaluate whether vertebral augmentation technology increases the occurrence of adjacent vertebral fractures in patients with osteoporotic vertebral compression fractures (OVCFs).

MATERIALS AND METHODS

Databases, including MEDLINE, EMBASE and Cochrane library, were retrieved via PRISMA covering 1987 to 2015. The number of patients who suffered from adjacent secondary vertebral fractures was calculated. A meta-analysis, using indexes of odds ratios (OR) and 95% confidence intervals (95% CI), was conducted with STATA software. Subgroup investigations were conducted according to the operation methods and the duration of observation. Sensitivity analysis and publication bias were also evaluated.

RESULTS

Ten randomized controlled trials (RCTs) met our inclusion criteria. Our results indicated there was no statistically significant difference in the occurrence rate of adjacent vertebral fractures between manipulation of vertebral augmentation and non-surgical treatment (OR = 0.89, 95% CI = 0.58-1.37). Neither subgroup investigations based on selection of operation nor duration of follow-up time showed marked differences. A sensitivity analysis did not identify specific trails seriously deflected. No obvious publication bias was identified.

CONCLUSION

Despite various limitations in the present study, our data demonstrated that using vertebral augmentation was not related to increasing incidence of subsequent adjacent vertebral fractures.

Vertebral Fractures: Clinical Importance and Management

Vertebral fractures are common and can result in acute and chronic pain, decreases in quality of life, and diminished lifespan. The identification of vertebral fractures is important because they are robust predictors of future fractures. The majority of vertebral fractures do not come to clinical attention. Numerous modalities exist for visualizing suspected vertebral fracture. Although differing definitions of vertebral fracture may present challenges in comparing data between different investigations, at least 1 in 5 men and women aged >50 years have one or more vertebral fractures. There is clinical guidance to target spine imaging to individuals with a high probability of vertebral fracture. Radiology reports of vertebral fracture need to clearly state that the patient has a "fracture," with further pertinent details such as the number, recency, and severity of vertebral fracture, each of which is associated with risk of future fractures. Patients with vertebral fracture should be considered for antifracture therapy. Physical and pharmacologic modalities of pain control and exercises or physiotherapy to maintain spinal movement and strength are important components in the care of vertebral fracture patients.

Clinical Management of Vertebral Compression Fractures

Vertebral compression fractures (VCF's) are the most common form of osteoporotic fractures. Whether symptomatic or asymptomatic, they both represent a high risk for not only vertebral but also nonvertebral fractures in untreated populations. This high risk of future fracture after a VCF is independent of the T-score because bone strength is a combination of bone mineral density and bone quality. VCFs are the single greatest risk for future fractures at all other skeletal sites in untreated populations, including hip fractures. They are often unrecognized despite their exceptionally high prevalence in all genders and most ethnic groups as age increases. This article highlights some of the key messages about VCF's, and how assessment for their presence and then management will reduce the risk of all osteoporotic fractures.

Epidemiology of Vertebral Fractures

Vertebral fractures are one of the most common fractures associated with skeletal fragility and can cause as much morbidity as hip fractures. However, the epidemiology of vertebral fractures differs from that of osteoporotic fractures at other skeletal sites in important ways, largely because only one quarter to one-third of vertebral fractures are recognized clinically at the time of their occurrence and otherwise require lateral spine imaging to be recognized. This article first reviews the prevalence and incidence of clinical and radiographic vertebral fractures in populations across the globe and secular trends in the incidence of vertebral fracture over time. Next, associations of vertebral fractures with measures of bone mineral density and bone microarchitecture are reviewed followed by associations of vertebral fracture with various textural measures of trabecular bone, including trabecular bone score. Finally, the article reviews clinical risk factors for vertebral fracture and the association of vertebral fractures with morbidity, mortality, and other subsequent adverse health outcomes.

Subsequent Vertebral Fractures Post Cement Augmentation of the Thoracolumbar Spine: Does it Correlate With Level-specific Bone Mineral Density Scores?

STUDY DESIGN

A case-control study.

OBJECTIVE

In this study, we investigated the correlation between level-specific preoperative bone mineral density and subsequent vertebral fractures. We also identified factors associated with subsequent vertebral fractures.

SUMMARY OF BACKGROUND DATA

Complications of cement augmentation of the spine include subsequent vertebral fractures, leading to unnecessary morbidity and more treatment. Ability to predict at-risk vertebra will help guide management.

METHODS

We studied all patients with osteoporotic compression fractures who underwent cement augmentation in a single institution from November 2001 to December 2010 by a single surgeon. Association between level-specific bone mineral density T-scores and subsequent fractures was assessed. Multivariable analysis was performed to identify significant factors associated with subsequent vertebral fractures.

RESULTS

93 patients followed up for a mean duration of 25.1 months (12-96) had a mean age of 76.8 years (47-99). Vertebroplasty was performed in 58 patients (62.4%) on 68 levels and kyphoplasty in 35 patients (37.6%) on 44 levels. Refracture was seen in 16 patients (17.2%). The time to subsequent fracture post cement augmentation was 20.5 months (2-90). For refracture cases, 43.8% (7/16) fractured in the adjacent vertebrae. Subsequently fractured vertebra had a mean T-score of -2.860 (95% confidence interval -3.268 to -2.452) and nonfractured vertebra had a mean T-score of -2.180 (95% confidence interval -2.373 to -1.986). A T-score of -2.2 or lower is predictive of refracture at that vertebra (P = 0.047). Odds ratio increases with decreasing T-scores from -2.2 or lower to -2.6 or lower. A T-score of -2.6 or lower gives no additional predictive advantage. After multivariable analysis, age (P = 0.049) and loss of preoperative anterior vertebral height (P = 0.017) are associated with refracture.

CONCLUSION

Level-specific T-scores are predictive of subsequent fractures and the odds ratio increases with lower T-scores from -2.2 or less to -2.6 or less. They have a low positive predictive value, but a high negative predictive value for subsequent fractures. Other significant associations with subsequent refractures include age and anterior vertebral height.

LEVEL OF EVIDENCE

4.

Minimally invasive procedures for the management of vertebral bone pain due to cancer: The EAPC recommendations

BACKGROUND

Image-guided percutaneous ablation methods have proved effective for treatment of benign bone tumors and for palliation of metastases involving the bone. However, the role of these techniques is controversial and has to be better defined in the setting of palliative care.

METHODS

A systematic review of the existing data regarding minimally invasive techniques for the pain management of vertebral bone metastases was performed by experts of the European Palliative Care Research Network.

RESULTS

Only five papers were taken into consideration after performing rigorous screening according to inclusion and exclusion criteria (low number of patients, retrospective series, proceedings).

DISCUSSION

According to the present data a recommendation should be made to perform kiphoplasty in patients with vertebral tumors or metastases. However, the strength of this recommendation was based on one randomized controlled study. Several weaknesses and low quality of study design were observed with other techniques.

CONCLUSION

Further randomized controlled trials are required to improve the strength of evidence available to suggest these procedures on large scale. Until then, the balance of evidence favors the use of these procedures in a small select cohort of patients with severe and disabling back pain refractory to medical therapy.

Bone Cement Dislodgement: One of Complications Following Bone Cement Augmentation Procedures for Osteoporotic Spinal Fracture

Bone cement augmentation procedures have been getting more position as a minimally invasive surgical option for osteoporotic spinal fractures. However, complications related to these procedures have been increasingly reported. We describe a case of bone cement dislodgement following cement augmentation procedure for osteoporotic spinal fracture by reviewing the patient's medical records, imaging results and related literatures. A 73-year-old woman suffering back and buttock pain following a fall from level ground was diagnosed as an osteoporotic fracture of the 11th thoracic spine. Percutaneous kyphoplasty was performed for this lesion. Six weeks later, the patient complained of a recurrence of back and buttock pain. Radiologic images revealed superior dislodgement of bone cement through the 11th thoracic superior endplate with destruction of the lower part of the 10th thoracic spine. Staged anterior and posterior fusion was performed. Two years postoperatively, the patient carries on with her daily living without any significant disability. Delayed bone cement dislodgement can occur as one of complications following bone cement augmentation procedure for osteoporotic spinal fracture. It might be related to the presence of intravertebral cleft, lack of interdigitation of bone cement with the surrounding trabeculae, and possible damage of endplate during ballooning procedure.

Percutaneous vertebroplasty for osteoporotic vertebral compression fracture

BACKGROUND

Percutaneous vertebroplasty is widely used to treat acute and subacute painful osteoporotic vertebral fractures although recent placebo-controlled trials have questioned its value.

OBJECTIVES

To synthesise the available evidence regarding the benefits and harms of vertebroplasty for treatment of osteoporotic vertebral fractures.

SEARCH METHODS

We searched CENTRAL, MEDLINE and EMBASE up to November 2014. We also reviewed reference lists of review articles, trials and trial registries to identify any other potentially relevant trials.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) including adults with painful osteoporotic vertebral fractures of any duration and comparing vertebroplasty with placebo (sham), usual care, or any other intervention. As it is least prone to bias, vertebroplasty compared with placebo was the primary comparison. Major outcomes were mean overall pain, disability, disease-specific and overall health-related quality of life, patient-reported treatment success, new symptomatic vertebral fractures and number of other serious adverse events.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected trials for inclusion, extracted data, performed 'Risk of bias' assessment and assessed the quality of the body of evidence for the main outcomes using GRADE.

MAIN RESULTS

Eleven RCTs and one quasi-RCT conducted in various countries were included. Two trials compared vertebroplasty with placebo (209 randomised participants), six compared vertebroplasty with usual care (566 randomised participants) and four compared vertebroplasty with kyphoplasty (545 randomised participants). Trial size varied from 34 to 404 participants, most participants were female, mean age ranged between 63.3 and 80 years, and mean symptom duration varied from a week to more than six months.Both placebo-controlled trials were judged to be at low overall risk of bias while other included trials were generally considered to be at high risk of bias across a range of criteria, most seriously due to lack of participant and study personnel blinding.Compared with placebo, there was moderate quality evidence based upon two trials that vertebroplasty provides no demonstrable benefits with respect to pain, disability, disease-specific or overall quality of life or treatment success. At one month, mean pain (on a scale 0 to 10, higher scores indicate more pain) was 5 points with placebo and 0.7 points better (1.5 better to 0.15 worse) with vertebroplasty, an absolute pain reduction of 7% (15% better to 1.5% worse) and relative reduction of 10% (21% better to 2% worse) (two trials, 201 participants). At one month, mean disability measured by the Roland Morris Disability Questionnaire (scale range 0 to 23, higher scores indicate worse disability) was 13.6 points in the placebo group and 1.1 points better (2.9 better to 0.8 worse) in the vertebroplasty group, absolute improvement in disability 4.8% (12.8% better to 3.3% worse), relative change 6.3% better (17.0% better to 4.4% worse) (two trials, 201 participants).At one month, disease-specific quality of life measured by the QUALEFFO (scale 0 to 100, higher scores indicating worse quality of life) was 2.4 points in the placebo group and 0.40 points worse (4.58 better to 5.38 worse) in the vertebroplasty group, absolute change: 0.4% worse (5% worse to 5% better), relative change 0.7% worse (9% worse to 8% better (based upon one trial, 73 participants). At one month overall quality of life measured by the EQ5D (0 = death to 1 = perfect health, higher scores indicate greater quality of life at one month was 0.27 points in the placebo group and 0.05 points better (0.01 worse to 0.11 better) in the vertebroplasty group, absolute improvement in quality of life 5% (1% worse to 11% better), relative change 18% better (4% worse to 39% better) (two trials, 201 participants). Based upon one trial (78 participants) at one month, 9/40 (or 225 per 1000) people perceived that treatment was successful in the placebo group compared with 12/38 (or 315 per 1000; range 150 to 664) in the vertebroplasty group, RR 1.40 (95% CI 0.67 to 2.95), absolute risk difference 9% more reported success (11% fewer to 29% more); relative change 40% more reported success (33% fewer to 195% more).Based upon moderate quality evidence from three trials (one placebo, two usual care, 281 participants) with up to 12 months follow-up, we are uncertain whether or not vertebroplasty increases the risk of new symptomatic vertebral fractures (28/143 observed in the vertebroplasty group compared with 19/138 in the control group; RR 1.47 (95% CI 0.39 to 5.50).Similary, based upon moderate quality evidence from two placebo-controlled trials (209 participants), we are uncertain about the exact risk of other adverse events (3/106 were observed in the vertebroplasty group compared with 3/103 in the placebo group; RR 1.01 (95% CI 0.21 to 4.85)). Notably, serious adverse events reported with vertebroplasty included osteomyelitis, cord compression, thecal sac injury and respiratory failure.Our subgroup analyses provided limited evidence that the effects did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks. Including data from the six trials that compared vertebroplasty with usual care in a sensitivity analyses inconsistently altered the primary results, with all combined analyses displaying substantial to considerable heterogeneity.

AUTHORS' CONCLUSIONS

Based upon moderate quality evidence, our review does not support a role for vertebroplasty for treating osteoporotic vertebral fractures in routine practice. We found no demonstrable clinically important benefits compared with a sham procedure and subgroup analyses indicated that results did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks. Sensitivity analyses confirmed that open trials comparing vertebroplasty with usual care are likely to have overestimated any benefit of vertebroplasty. Correcting for these biases would likely drive any benefits observed with vertebroplasty towards the null, in keeping with findings from the placebo-controlled trials.Numerous serious adverse events have been observed following vertebroplasty. However due to the small number of events, we cannot be certain about whether or not vertebroplasty results in a clinically important increased risk of new symptomatic vertebral fractures and/or other serious adverse events. Patients should be informed about both the lack of high quality evidence supporting benefit of vertebroplasty and its potential for harm.