Percutaneous Vertebroplasty in Osteoporotic Patients: An Institutional Experience of 1,634 Patients with Long-Term Follow-Up

Conservative Treatments in the Management of Acute Painful Vertebral Compression Fractures: A Systematic Review and Network Meta-Analysis

Importance

Osteoporotic vertebral compression fractures (VCFs) frequently cause substantial pain and reduced mobility, posing a major health problem. Despite the critical need for effective pain management to restore functionality and improve patient outcomes, the value of various conservative treatments for acute VCF has not been systematically investigated.

Objective

To assess and compare different conservative treatment options in managing acute pain related to VCF.

Data Sources

On May 16, 2023, 4 databases-PubMed, Embase, Scopus, and CINAHL-were searched. In addition, a gray literature search within Scopus and Embase was also conducted.

Study Selection

Included studies were prospective comparative and randomized clinical trials that assessed conservative treatments for acute VCF.

Data Extraction and Synthesis

Data extraction and synthesis were performed by 2 authors according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Network Meta-Analyses recommendations. A frequentist graph-theoretical model and a random-effects model were applied for the meta-analysis.

Main Outcomes and Measures

Primary outcomes were short-term (4 weeks) pain during activity and long-term (latest available follow-up) nonspecified pain in patients with acute VCF.

Results

The study included 20 trials, encompassing 2102 patients, and evaluated various interventions for managing VCF. Calcitonin (standardized mean difference [SMD], -4.86; 95% CI, -6.87 to -2.86) and nonsteroidal anti-inflammatory drugs (NSAIDs; SMD, -3.94; 95% CI, -7.30 to -0.58) were beneficial regarding short-term pain during activity compared with placebo. For long-term nonspecific pain management, bisphosphonates were associated with inferior pain outcomes compared with daily (SMD, 1.21; 95% CI, 0.11 to 2.31) or weekly (SMD, 1.13; 95% CI, 0.05 to 2.21) administration of teriparatide, with no treatment being superior to NSAIDs. The qualitative analysis of adverse events highlighted that typical adverse events associated with these medications were observed.

Conclusions and Relevance

NSAIDs and teriparatide may be the preferred treatment options for pain management in acute osteoporotic VCF. Although calcitonin also proved to be beneficial, its safety profile and potential adverse effects restrict its widespread application. The limited evidence on braces and analgesics underscores the urgent need for future research.

Vertebroplasty versus Active Control Intervention for Chronic Osteoporotic Vertebral Compression Fractures: The VERTOS V Randomized Controlled Trial

Background Evidence regarding percutaneous vertebroplasty (PV) for chronic painful osteoporotic vertebral compression fractures (OVCFs) remains limited. Purpose To compare pain relief, quality of life, and disability between PV and active control (anesthetic infiltration) interventions for chronic OVCF. Materials and Methods This prospective randomized clinical trial was conducted between May 2013 and June 2019 in participants with pain due to OVCF lasting longer than 3 months with bone marrow edema present at MRI. Study participants were randomly assigned to undergo PV (n = 40) or active control intervention (n = 40). The primary outcome was pain severity, assessed with the visual analog scale (VAS) (range, 0-10) during 12 months after treatment. Secondary outcomes included Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO) score (range, 0-100) and Roland Morris Disability Questionnaire (RMDQ) score (range, 0-100). Outcomes were analyzed according to a longitudinal multilevel model used to test the difference between groups in change from baseline across follow-up. Results The mean age of the 80 participants (54 women) was 69 years ± 10 (SD) in the PV group and 71 years ± 10 in the active control group. VAS score was 7.6 (95% CI: 7.0, 8.2) in the PV group and 7.3 (95% CI: 6.9, 7.8) in the active control group at baseline (P = .47) and 3.9 (95% CI: 3.1, 4.8) and 5.1 (95% CI: 4.3, 6.0), respectively, at month 12 (P = .045). At month 12, the group difference from baseline was 1.3 (95% CI: 0.1, 2.6; P = .02) for VAS, 5.2 (95% CI: 0.9, 9.4; P = .02) for QUALEFFO, and 7.1 (95% CI: -3.3, 17.5; P = .18) for RMDQ, favoring the PV group. Conclusion In the treatment of pain caused by chronic OVCFs, PV is more effective for pain relief and quality of life improvement than anesthetic injection alone, with similar improvement for disability between the groups. Clinical trial registration no. NCT01963039 © RSNA, 2023 See also the editorial by Beall and De Leacy in this issue.

Vertebral Augmentation: Is It Time to Get Past the Pain? A Consensus Statement from the Sardinia Spine and Stroke Congress

Vertebral augmentation has been used to treat painful vertebral compression fractures and metastatic lesions in millions of patients around the world. An international group of subject matter experts have considered the evidence, including but not limited to mortality. These considerations led them to ask whether it is appropriate to allow the subjective measure of pain to so dominate the clinical decision of whether to proceed with augmentation. The discussions that ensued are related below.

Predictive Factors for Sustained Pain after (sub)acute Osteoporotic Vertebral Fractures. Combined Results from the VERTOS II and VERTOS IV Trial

Purpose

Osteoporotic vertebral compression fractures are treated conservatively or in selected cases with percutaneous vertebroplasty (PV). The purpose of this retrospective analysis is to determine predictive factors for a high visual analogue scale (VAS) pain score after conservative, sham or PV and is based on previously published randomized trials.

Methods

The VERTOS II compared conservative versus PV, and VERTOS IV compared sham versus PV treatment. The conservative group received pain medication. The sham and PV group received subcutaneous lidocaine/bupivacaine. In addition, the PV group received cementation, which was simulated in the sham group. Nineteen different predictors of high (≥ 5) versus low (< 5) VAS pain score at 12 months were investigated.

Results

20.7% of patients in the PV group demonstrated a VAS ≥ 5 at the 12-month, compared to 40.1% in the conservative or sham group, with a significant difference (χ²(1) = 15.26, p < 0.0001, OR = 2.57, 95% CI = 1.59 to 4.15). In the subgroup analysis, we detected five predictors for the risk of high pain scores (VAS ≥ 5 after 12 months follow-up), namely: female, baseline VAS > 8, long-term baseline pain, mild/severe Genant and new fractures.

Conclusions

Statistically significant more patients had a high pain score at 12 months in the sham and conservative group when compared with the PV group. Five predictors were identified for sustained high local back pain, regardless of the received treatment. Patients with moderate fracture deformity were less likely to have high pain scores at 12 months if they received PV than if they had sham or conservative therapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00270-022-03170-7.

A novel "three-dimensional-printed individual guide template-assisted percutaneous vertebroplasty" for osteoporotic vertebral compression fracture: a prospective, controlled study

BACKGROUND

Conventional percutaneous vertebroplasty (PVP) are mainly guided by C-arm fluoroscopy, and it usually leads to excessive X-ray radiation exposure to patients, surgeons, and anesthetists. Moreover, multi-time fluoroscope may prolong the operation time. 3D-printed template could help minimize fluoroscopy shot times and fluoroscopy dosage during operation, and shorten operation time. We perform this study to compare the efficacy and accuracy of PVP assisted by "three-dimensional printed individual guide template" versus conventional PVP.

METHOD

Patients who suffered acute painful single segment osteoporotic vertebral compression fracture(OVCF) needed operative treatment were randomly assigned into three-dimensional printing individual guide template-assisted percutaneous vertebroplasty group (group A) or conventional PVP guided by C-arm fluoroscopy group (group B) at a 1:1 ratio. Fluoroscopy times for puncture points (FTPP), total radiation dosages (TRD), total fluoroscopy time (TFT), and total operation time (TOT) were recorded as the main evaluation factors to evaluate the two operation procedures.

RESULTS

A total of 36 acute painful single segment OVCF patients were successfully operated on, and each group has 18 patients. None of the patients presented symptomatic complications. The surgical success rate in group A was 94.4%(17/18), one patient in the group A was failed and then operated by conventional procedure. FTPP (1.8 ± 0.8 in group A vs 5.2 ± 1.9 in group B, P < 0.05), TRD (4.9 ± 0.9 mGy vs 7.9 ± 1.6 mGy, P < 0.05), TFT (16.7 ± 2.9 vs 26.6 ± 5.3, P < 0.05), and total operation time (19.4 ± 2.4 min vs 27.8 ± 4.0 min, P < 0.05) were presented statistically difference in the two groups. The incidence of cement leakage occurred in group A (3/18, 16.7%) was less than that occurred in group B (7/18, 38.9%) (P > 0.05).

CONCLUSIONS

Compared with the conventional PVP, "three-dimensional-printed individual guide template-assisted PVP" could minimize fluoroscopy shot times during operation and fluoroscopy dosage, shorten operation time, and is a more precise and feasible operation method.

TRIAL REGISTRATION

The present study was registered with the Chinese Clinical Trial Registry (ChiCTR) ( http://www.chictr.org.cn ), and its registration no. is ChiCTR1900024283.

Vertebroplasty versus sham procedure for painful acute osteoporotic vertebral compression fractures (VERTOS IV): randomised sham controlled clinical trial

OBJECTIVE

To assess whether percutaneous vertebroplasty results in more pain relief than a sham procedure in patients with acute osteoporotic compression fractures of the vertebral body.

DESIGN

Randomised, double blind, sham controlled clinical trial.

SETTING

Four community hospitals in the Netherlands, 2011-15.

PARTICIPANTS

180 participants requiring treatment for acute osteoporotic vertebral compression fractures were randomised to either vertebroplasty (n=91) or a sham procedure (n=89).

INTERVENTIONS

Participants received local subcutaneous lidocaine (lignocaine) and bupivacaine at each pedicle. The vertebroplasty group also received cementation, which was simulated in the sham procedure group.

MAIN OUTCOME MEASURES

Main outcome measure was mean reduction in visual analogue scale (VAS) scores at one day, one week, and one, three, six, and 12 months. Clinically significant pain relief was defined as a decrease of 1.5 points in VAS scores from baseline. Secondary outcome measures were the differences between groups for changes in the quality of life for osteoporosis and Roland-Morris disability questionnaire scores during 12 months' follow-up.

RESULTS

The mean reduction in VAS score was statistically significant in the vertebroplasty and sham procedure groups at all follow-up points after the procedure compared with baseline. The mean difference in VAS scores between groups was 0.20 (95% confidence interval -0.53 to 0.94) at baseline, -0.43 (-1.17 to 0.31) at one day, -0.11 (-0.85 to 0.63) at one week, 0.41 (-0.33 to 1.15) at one month, 0.21 (-0.54 to 0.96) at three months, 0.39 (-0.37 to 1.15) at six months, and 0.45 (-0.37 to 1.24) at 12 months. These changes in VAS scores did not, however, differ statistically significantly between the groups during 12 months' follow-up. The results for secondary outcomes were not statistically significant. Use of analgesics (non-opioids, weak opioids, strong opioids) decreased statistically significantly in both groups at all time points, with no statistically significant differences between groups. Two adverse events occurred in the vertebroplasty group: one respiratory insufficiency and one vasovagal reaction.

CONCLUSIONS

Percutaneous vertebroplasty did not result in statistically significantly greater pain relief than a sham procedure during 12 months' follow-up among patients with acute osteoporotic vertebral compression fractures.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01200277.

Analysis of vertebral augmentation practice patterns: a 2016 update

Objective

To evaluate procedure utilization patterns for vertebroplasty and kyphoplasty in the US Medicare population from 2004 to 2014.

Methods

The analysis was performed using the Centers for Medicare and Medicaid Services database of specialty utilization files for the fee for service (FFS) Medicare population.

Results

The FFS Medicare population increased by 28% with an annual increase of 2.5% from 2004 to 2014. Utilization of vertebroplasty procedures decreased by 63% with an average annual decrease of 9.5% from 2004 to 2014 per 100 000 FFS Medicare beneficiaries. During the same time period, kyphoplasty procedures decreased by a total of 10%, with an average annual decrease of 1.3%. For augmentation generally (combined vertebroplasty/kyphoplasty data) there was thus an overall decrease in the rate per 100 000 Medicare population of 32% from 2004 to 2014, with an average annual decrease of 4.8%. The majority of vertebroplasty procedures were performed by radiologists whereas the majority of kyphoplasties were performed by orthopedic surgeons and neurosurgeons.

Conclusions

There has been a significant decline in vertebroplasty and kyphoplasty procedures in the FFS Medicare population between 2004 and 2014.

Comparing Percutaneous Vertebroplasty and Conservative Therapy for Treating Osteoporotic Compression Fractures in the Thoracic and Lumbar Spine: A Systematic Review and Meta-Analysis

BACKGROUND

Vertebral compression fractures are a common complication of osteoporosis and are often treated by percutaneous vertebroplasty (PVP). The ability of this procedure to relieve pain better than conservative treatment is still debated. The purpose of this study was to compare the degree and duration of pain relief following PVP with that following conservative treatment for osteoporotic compression fractures by means of meta-analysis of randomized controlled trials.

METHODS

The CENTRAL (Cochrane Central Register of Controlled Trials), MEDLINE, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Web of Science databases were queried for randomized controlled trials comparing PVP with conservative treatment or placebo/sham. The methodological quality was assessed according to the Cochrane Collaboration's domain-based evaluation framework. Random-effects meta-analysis of the raw mean difference between groups in change in pain level was performed, with sensitivity analyses and the Egger test for potential publication bias.

RESULTS

Of 209 records found, 11 were considered relevant, involving 1,048 participants. The risk of bias was considered low in 10 studies and high in 1. The 531 patients treated with PVP had a significantly lower pain level compared with the control group at 1 to 2 weeks, 2 to 3 months, and 12 months. The 95% CI (confidence interval) of the pooled effect size at every time interval included the score of 1.5, considered to be the minimal clinically important difference. The largest pooled effect size of -1.4 (95% CI, -2.3 to -0.5) was found during the first 1 to 2 weeks. The heterogeneity was high at all 3 time points (I(2), 71% to 96%). No significant publication bias was detected.

CONCLUSIONS

Up to 1 year postoperatively, the effect of PVP exceeded the effect of conservative therapy with respect to pain relief in patients with osteoporotic compression fractures. The effect size was significant and close to the minimal clinically important difference.

An evaluation of the functional and radiological results of percutaneous vertebroplasty versus conservative treatment for acute symptomatic osteoporotic spinal fractures

PURPOSE

This study aimed to compare the results of the two different treatment regimens (percutaneous vertebroplasty (PV) and conservative treatment (CT)) regarding to efficacy, quality of life, functional and radiological results in patients with acute osteoporotic vertebral compression fractures (OVF).

METHODS

The study comprised 83 patients who presented with complaints of OVF associated with osteoporosis and were treated with CT (37) or PV (46). All patients were evaluated according to preoperative and postoperative visual analogue scale (VAS), Oswestry disability index (ODI) and plain radiographs.

RESULTS

All patients in VP group reported a significant decrease in pain at 1st day postoperative. While Pain relief and functional outcomes were significantly better in PV group than CT at 1st and 3rd months according to VAS and ODI scores, there were no statistically significant differences between the groups at 6th months follow-up. The mean preoperative local sagittal Cobb angle (LSCA) and the mean vertebra corpus mid-level height (MVCH) were 42.3° and 14.6 mm in the PV group, while they were measured as 39.8° and 15.7 mm in CT group, respectively. 15.6° decreasing the LSCA and 10.2 mm increasing MVCH were noted in the PV group at the 6th month follow-up. While LSCA increased 19.1° and MVCH decreased 7.6mm in CT group at same time period (p<0.001).

CONCLUSIONS

Compared to the CT group, PV provides a rapid decrease of pain and an early return to daily life activities. Although improvement was observed on the radiological findings following treatment in the PV group, PV may not enhance the quality of life in patients with acute OVF at 6th months follow up.

Safety and Clinical Effectiveness of Percutaneous Vertebroplasty in the Elderly (≥80 years)

PURPOSE

To evaluate the safety and clinical effectiveness of percutaneous vertebroplasty (PVP) in patients aged 80 and over.

METHODS

One hundred and seventy-three patients (127 women, 46 men; mean age = 84.2y) underwent 201 PVP procedures (391 vertebrae) in our institution from June 2008 to March 2012. One hundred and twenty-six patients (73 %) had osteoporotic vertebral compression fractures (VCF), 36 (20.5 %) were treated for tumour lesions, and the remaining 11 (6.5 %) for lesions from another cause. Comorbidities and American Society of Anesthesiologists (ASA) scores were assessed before treatment. Periprocedural and delayed complications were systematically recorded. A qualitative scale was used to evaluate pain relief at 1-month follow-up, ranging from significant pain worsening to marked improvement or disappearance. New fracture occurrence was assessed on follow-up imaging.

RESULTS

Forty-five percent of patients had pretreatment ASA class scores ≥3. No major complication occurred. Pain was unchanged in 16.9 % of cases, mildly improved in 31.5 %, and disappeared in 47.8 %. We identified 27 (11 %) symptomatic new VCFs in patients with osteoporosis on follow-up imaging. The mean delay in diagnosis of new fractures was 5 ± 8.7 months.

CONCLUSIONS

Even in the elderly, PVP remains a safe and effective technique for pain relief, independently of the underlying disease.

KEY POINTS

• Post-PVP pain improvement was observed in 79.3 % of elderly patients. • PVP remains a safe technique in elderly patients. • No decompensation of comorbidity was observed in our series.

Results of Vertebral Augmentation Treatment for Patients of Painful Osteoporotic Vertebral Compression Fractures: A Meta-Analysis of Eight Randomized Controlled Trials

Background

In 2009 two RCTs were publicated to question the efficacy of vertebroplasty comparing with sham treatment (ST) in the New England Journal of Medicine (NEJM), which provoked an academic debate on the efficacy of PVA. The purposes of our study were to compare clinical differences in pain relief, spinal functional outcomes, and overall quality of life between PVA and CT for painful osteoporotic VCFs.

Methods

We searched PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials and Web of Knowledge from January 1980 to June 2013 with Medical Subject Headings terms and keywords. Risk of bias in the included studies was assessed in accordance with the Cochrane risk of bias tool. In this Meta-analysis dichotomous and continuous variables were calculated using the risk ratio (RR) and standardized mean difference (SMD), respectively.

Results

Eight studies involving 987 patients met the criteria for inclusion. The VAS SMD was favoring the experimental group significantly (p < 0.001). Subgroup analysis suggested that the patients performed PVA with mean fracture age less than 3 months would got pain relief earlier and more durable than the control group (P <0.05). The SMD of spinal function assessed with RDQ and Oswestry LBP data was in favor of the experimental groups. QOL outcome improvement was demonstrated statistically significant at early, middle and late-term follow-up for PVA than the control group (P <0.05).

Conclusions

In conclusion, this meta-analysis, which evaluated PVA for osteoporotic VCFs, demonstrated significant improvement regarding VAS, spinal function and QOL outcomes. The optimal fracture age was less than 12 weeks.

Update of vertebral cementoplasty in porotic patients

Vertebroplasty (VP) is a percutaneous mini-invasive technique developed in the late 1980s as antalgic and stabilizing treatment in patients affected by symptomatic vertebral fracture due to porotic disease, traumatic injury and primary or secondary vertebral spine tumors. The technique consists of a simple metameric injection of an inert cement (poly-methyl-methacrylate, PMMA), through a needle by trans-peduncular, parapeduncular or trans-somatic approach obtaining a vertebral augmentation and stabilization effect associated with pain relief. The technique is simple and fast, and should be performed under fluoroscopy or CT guidance in order to obtain a good result with low complication rate. The aim of this paper is to illustrate the utility of VP, the indications-contraindications criteria, how to technically perform the technique using imaging guidance, and the results and complications of this treatment in patients affected by symptomatic vertebral compression fracture.

Effects of vertebroplasty on endplate subsidence in elderly female spines

OBJECT

The aim in this study was to quantify the effects of vertebroplasty on endplate subsidence in treated and adjacent vertebrae and their relationship to endplate thickness and underlying trabecular bone in elderly female spines.

METHODS

Vertebral compression fractures were created in female cadaveric (age range 51-88 years) thoracolumbar spine segments. Specimens were placed into either the control or vertebroplasty group (n = 9/group) such that bone mineral density, trabecular microarchitecture, and age were statistically similar between groups. For the vertebroplasty group, polymethylmethacrylate bone cement was injected into the fractured vertebral body under fluoroscopy. Cyclic compression (685-1370 N sinusoid) was performed on all spine segments for 115,000 cycles. Micro-CT scans were obtained before and after cyclic loading to quantify endplate subsidence. Maximum subsidence was compared between groups in the caudal endplate of the superior adjacent vertebra (SVcau); cranial (TVcra) and caudal (TVcau) endplates of the treated vertebra; and the cranial endplate of the inferior adjacent vertebra (IVcra). In addition, micro-CT images were used to quantify average endplate thickness and trabecular bone volume fraction. These parameters were then correlated with maximum endplate subsidence for each endplate.

RESULTS

The maximum subsidence in SVcau endplate for the vertebroplasty group (0.34 ± 0.58 mm) was significantly (p < 0.05) greater than for the control group (-0.13 ± 0.27 mm). Maximum subsidence in the TVcra, TVcau, and IVcra endplates were greater in the vertebroplasty group, but these differences were not significant (p > 0.16). Increased subsidence in the vertebroplasty group manifested locally in the anterior region of the SVcau endplate and in the posterior region of the TVcra and TVcau endplates (p < 0.10). Increased subsidence was observed in thinner endplates with lower trabecular bone volume fraction for both vertebroplasty and control groups (R(2) correlation up to 62%). In the SVcau endplate specifically, these 2 covariates aided in understanding subsidence differences between vertebroplasty and control groups.

CONCLUSIONS

Bone cement injected during vertebroplasty alters local biomechanics in elderly female spines, resulting in increased endplate disruption in treated and superior adjacent vertebrae. More specifically, bone cement increases subsidence in the posterior regions of the treated endplates and the anterior region of the superior caudal endplate. This increased subsidence may be the initial mechanism leading to subsequent compression fractures after vertebroplasty, particularly in vertebrae superior to the treated level.

Fracture prevention by prophylactic femoroplasty of the proximal femur--metallic compared with cemented augmentation

OBJECTIVES

To compare 2 different femoral neck augmentation techniques at improving the mechanical strength of the femoral neck.

METHODS

Twenty pairs of human cadaveric femora were randomly divided into 2 groups. In 1 group, the femora were augmented with a steel spiral; the other group with the cemented technique. The untreated contralateral side served as an intraindividual control. Fracture strength was evaluated using an established biomechanical testing scenario mimicking a fall on the greater trochanter (Hayes fall).

RESULTS

The peak load to failure was significantly higher in the steel spiral group (P = 0.0024) and in the cemented group (P = 0.001) compared with the intraindividual controls. The peak load to failure showed a median of 3167 N (1825-5230 N) in the spiral group and 2485 N (1066-4395 N) in the spiral control group. The peak load to failure in the cemented group was 3698 N (SD ± 1249 N) compared with 2763 N (SD ± 1335 N) in the cement control group. Furthermore, fracture displacement was clearly reduced in the steel spiral group.

CONCLUSIONS

Femoral augmentations using steel spirals or cement-based femoroplasty are technically feasible procedures. Our results demonstrate that a prophylactic reinforced proximal femur has higher strength when compared with the untreated contralateral limb. Prophylactic augmentation has potential to become an auxiliary treatment option to protect the osteoporotic proximal femur against fracture.

Vertebroplasty increases compression of adjacent IVDs and vertebrae in osteoporotic spines

BACKGROUND CONTEXT

Approximately 25% of vertebroplasty patients experience subsequent fractures within 1 year of treatment, and vertebrae adjacent to the cemented level are up to three times more likely to fracture than those further away. The increased risk of adjacent fractures postaugmentation raises concerns that treatment of osteoporotic compression fractures with vertebroplasty may negatively impact spine biomechanics.

PURPOSE

To quantify the biomechanical effects of vertebroplasty on adjacent intervertebral discs (IVDs) and vertebral bodies (VBs).

STUDY DESIGN

A biomechanics study was conducted using cadaveric thoracolumbar spinal columns from elderly women (age range, 51-98 years).

METHODS

Five level motion segments (T11-L3) were assigned to a vertebroplasty treated or untreated control group (n=10/group) such that bone mineral density (BMD), trabecular architecture, and age were similar between groups. Compression fractures were created in the L1 vertebra of all specimens, and polymethylmethacrylate bone cement was injected into the fractured vertebra of vertebroplasty specimens. All spine segments underwent cyclic axial compression for 115,000 cycles. Microcomputed tomography imaging was performed before and after cyclic loading to quantify compression in adjacent VBs and IVDs.

RESULTS

Cyclic loading increased strains 3% on average in the vertebroplasty group when compared with controls after 115,000 cycles. This global strain manifested locally as approximately fourfold more compression in the superior VB (T12) and two- to fourfold higher axial and circumferential deformations in the superior IVD (T12-L1) of vertebroplasty-treated specimens when compared with untreated controls. Low BMD and high cement fill were significant factors that explained the increased strain in the vertebroplasty-treated group.

CONCLUSIONS

These data indicate that vertebroplasty alters spine biomechanics resulting in increased compression of adjacent VB and IVD in severely osteoporotic women and may be the basis for clinical reports of adjacent fractures after vertebroplasty.

Effect of bone cement volume and stiffness on occurrences of adjacent vertebral fractures after vertebroplasty

Objective

The purpose of this study is to find the optimal stiffness and volume of bone cement and their biomechanical effects on the adjacent vertebrae to determine a better strategy for conducting vertebroplasty.

Methods

A three-dimensional finite-element model of a functional spinal unit was developed using computed tomography scans of a normal motion segment, comprising the T11, T12 and L1 vertebrae. Volumes of bone cement, with appropriate mechanical properties, were inserted into the trabecular core of the T12 vertebra. Parametric studies were done by varying the volume and stiffness of the bone cement.

Results

When the bone cement filling volume reached 30% of the volume of a vertebral body, the level of stiffness was restored to that of normal bone, and when higher bone cement exceeded 30% of the volume, the result was stiffness in excess of that of normal bone. When the bone cement volume was varied, local stress in the bony structures (cortical shell, trabecular bone and endplate) of each vertebra monotonically increased. Low-modulus bone cement has the effect of reducing strain in the augmented body, but only in cases of relatively high volumes of bone cement (>50%). Furthermore, varying the stiffness of bone cement has a negligible effect on the stress distribution of vertebral bodies.

Conclusion

The volume of cement was considered to be the most important determinant in endplate fracture. Changing the stiffness of bone cement has a negligible effect on the stress distribution of vertebral bodies.

Is there really no benefit of vertebroplasty for osteoporotic vertebral fractures? A meta-analysis

BACKGROUND

Osteoporotic vertebral compressed fractures (VCFs) are the most common osteoporotic fractures. Although percutaneous vertebroplasty (PVP) reportedly relieves pain and improves function, a recent pooled analysis from two multicenter randomized controlled trials concluded the improvement in pain and disability treated with PVP was similar to those with sham surgery.

QUESTIONS/PURPOSE

Using meta-analysis we therefore asked whether compared with either nonoperative therapy or a sham injection for patients with VCF, PVP would (1) better relieve pain, (2) provide greater improvement in pain-related disability, and (3) increase the recurrence of vertebral fractures.

METHODS

We searched PubMed, EMBASE, Medline, and the Cochrane library using the keywords "vertebroplasty AND osteoporosis OR fracture". We included nine of the 469 articles identified. Using a random effects model, we calculated the weighted mean differences to evaluate the pain reduction at different times as the primary outcome. Pain-related disability was assessed by a quality of life (QOL) measure. Improvement of QOL and recurrence of vertebral fractures were the secondary outcomes. We used subgroup analysis to reinvestigate pain relief and function improvement of PVP based on two different controls: nonoperative therapy and sham injection. The total number of patients was 886.

RESULTS

Pain scoring was similar between the PVP group and the sham injection group at 1 to 29 days and 90 days. However, compared with nonoperative therapy, PVP reduced pain at all times studied. QOL in the PVP group was improved or tended to be improved compared with QOL for both control groups. The risk of new fractures was similar between the PVP groups and both control groups.

CONCLUSIONS

Different control groups may have accounted for the different conclusions in the literature regarding the ability of PVP to relieve pain and restore function recovery. Compared with nonoperative treatment PVP relieved pain better and improved QOL. PVP did not increase the risk of new fractures.

LEVEL OF EVIDENCE

Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.