Vertebral body stenting versus kyphoplasty for the treatment of osteoporotic vertebral compression fractures: a randomized trial

A Toolbox of Bone Consolidation for the Interventional Radiologist

Bone consolidation is increasingly used in the treatment of both benign and malignant bone conditions. Percutaneous vertebroplasty, for example, has been shown to be useful in vertebral compression fractures in the VAPOUR trial which showed its superiority to placebo for pain reduction in the treatment of acute vertebral compressive fractures. Further tools have since been developed, such as kyphoplasty, spinal implants, and even developments in bone cements itself in attempt to improve outcome, such as chemotherapy-loaded cement or cement replacements such as radio-opaque silicon polymer. More importantly, bone fixation and its combination with cement have been increasingly performed to improve outcome. Interventional radiologists must first know the tools available, before they can best plan for their patients. This review article will focus on the tool box available for the modern interventional radiologist.

Innovative minimally invasive implants for osteoporosis vertebral compression fractures

With increasing population aging, osteoporosis vertebral compression fractures (OVCFs), resulting in severe back pain and functional impairment, have become progressively common. Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) as minimally invasive procedures have revolutionized OVCFs treatment. However, PVP- and PKP-related complications, such as symptomatic cement leakage and adjacent vertebral fractures, continue to plague physicians. Consequently, progressively more implants for OVCFs have been developed recently to overcome the shortcomings of traditional procedures. Therefore, we conducted a literature review on several new implants for OVCFs, including StaXx FX, Vertebral Body Stenting, Vesselplasty, Sky Bone Expander, Kiva, Spine Jack, Osseofix, Optimesh, Jack, and V-strut. Additionally, this review highlights the individualized applications of these implants for OVCFs. Nevertheless, current clinical studies on these innovative implants remain limited. Future prospective, randomized, and controlled studies are needed to elucidate the effectiveness and indications of these new implants for OVCFs.

Anterior thoracolumbar column reconstruction with the vertebral body stent-safety and efficacy

PURPOSE

The aim of this study was to assess safety and efficacy of vertebral body stenting (VBS) by analyzing (1) radiographic outcome, (2) clinical outcome, and (3) perioperative complications in patients with vertebral compression fractures treated with VBS at minimum 6-month follow-up.

METHODS

In this retrospective cohort study, 78 patients (61 ± 14 [21-90] years; 67% female) who have received a vertebral body stent due to a traumatic, osteoporotic or metastatic thoracolumbar compression fracture at our hospital between 2012 and 2020 were included. Median follow-up was 0.9 years with a minimum follow-up of 6 months. Radiographic and clinical outcome was analyzed directly, 6 weeks, 12 weeks, 6 months postoperatively, and at last follow-up.

RESULTS

Anterior vertebral body height of all patients improved significantly by mean 6.2 ± 4.8 mm directly postoperatively (p < 0.0001) and remained at 4.3 ± 5.1 mm at last follow-up compared to preoperatively (p < 0.0001). The fracture kyphosis angle of all patients improved significantly by mean 5.8 ± 6.9 degrees directly postoperatively (p < 0.0001) and remained at mean 4.9 ± 6.9 degrees at last follow-up compared to preoperatively (p < 0.0001). The segmental kyphosis angle of all patients improved significantly by mean 7.1 ± 7.6 degrees directly postoperatively (p < 0.0001) and remained at mean 2.8 ± 7.8 degrees at last follow-up compared to preoperatively (p = 0.03). Back pain was ameliorated from a preoperative median Numeric Rating Scale value of 6.5 to 3.0 directly postoperatively and further bettered to 1.0 six months postoperatively (p = 0.0001). Revision surgery was required in one patient after 0.4 years.

CONCLUSION

Vertebral body stenting is a safe and effective treatment option for osteoporotic, traumatic and metastatic compression fractures.

Treatment of A3.2 and A2 traumatic thoracolumbar spine compression fractures using vertebral body stenting: a 63-patient series

BACKGROUND

Percutaneous treatments for spinal injury are underused by neuroradiologists and spine surgeons, mainly owing to a lack of data on indications.

OBJECTIVE

To assess the safety and efficacy of vertebral body stenting (VBS) for post-traumatic A3.2 and A2 fractures (Magerl classification) and determine the factors that influence the improvements.

METHODS

We retrospectively reviewed patients who underwent VBS to treat a single traumatic thoracolumbar fracture from 2010 to 2019. Kyphosis, loss of vertebral body height (VBH), and clinical and functional outcomes (including the Visual Analog Scale pain score and Oswestry Disability Index) were assessed. We examined the overall effects of VBH in all patients by constructing a linear statistical model and evaluated whether the efficacy was dependent on the characteristics of the patients or fractures.

RESULTS

We included 63 patients comprising 44 A3.2 and 19 A2 fractures. No patient had worsening neurological symptoms or wound infection. The average rates of change were 67.1% (95% CI 59.1% to 75%) for kyphosis and 88.5% (95% CI 85.6% to 91.3%) for VBH (both p<0.0001). After 1 year, the VBS treatment was more effective for kyphosis in younger patients and at the L1 level, and for VBH in younger patients and cases of Magerl A3.2 fracture.

CONCLUSIONS

This large reported series on VBS validates this surgical treatment. All patients had improved kyphosis and restored VBH. We recommend using VBS rather than open surgery for A3.2 and A2 fractures at the thoracolumbar junction and in young patients.

Intraoperative complications of vertebral body stenting system

Background

Vertebral body stenting systems (VBSs) are superior to balloon kyphoplasty for performing vertebral augmentation and height restoration. However, VBS may likely result in more material-related complications that have been under-reported. Here, an 84-year-old female's vertebral stents "toppled over" before the filling cement was fully applied, thus necessitating an additional posterior fusion.

Case Description

An 84-year-old female presented with low back pain after a fall. Dynamic standing and decubitus X-rays revealed a vertebral compression fracture at T12 resulting in an intravertebral vacuum cleft (i.e., the lowermost level of diffuse idiopathic skeletal hyperostosis). When the VBS was performed, the stents "toppled over" just after removing the balloon catheters; we successfully restored with the cement volume in one stent but not the other, thus warranting an additional posterior fusion to maintain stability.

Conclusion

The proper injection of cement into a VBS requires dual correct stent positioning, and careful control of requisite stent expansion. In an 84-year-old female with a T12 vertebral body fracture and a remarkable vacuum cleft, the VBS procedure resulted in an inadvertent injection into one stent thus warranting a secondary posterior fusion.

The American Society of Pain and Neuroscience (ASPN) Evidence-Based Clinical Guideline of Interventional Treatments for Low Back Pain

Introduction

Painful lumbar spinal disorders represent a leading cause of disability in the US and worldwide. Interventional treatments for lumbar disorders are an effective treatment for the pain and disability from low back pain. Although many established and emerging interventional procedures are currently available, there exists a need for a defined guideline for their appropriateness, effectiveness, and safety.

Objective

The ASPN Back Guideline was developed to provide clinicians the most comprehensive review of interventional treatments for lower back disorders. Clinicians should utilize the ASPN Back Guideline to evaluate the quality of the literature, safety, and efficacy of interventional treatments for lower back disorders.

Methods

The American Society of Pain and Neuroscience (ASPN) identified an educational need for a comprehensive clinical guideline to provide evidence-based recommendations. Experts from the fields of Anesthesiology, Physiatry, Neurology, Neurosurgery, Radiology, and Pain Psychology developed the ASPN Back Guideline. The world literature in English was searched using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Scopus, and meeting abstracts to identify and compile the evidence (per section) for back-related pain. Search words were selected based upon the section represented. Identified peer-reviewed literature was critiqued using United States Preventive Services Task Force (USPSTF) criteria and consensus points are presented.

Results

After a comprehensive review and analysis of the available evidence, the ASPN Back Guideline group was able to rate the literature and provide therapy grades to each of the most commonly available interventional treatments for low back pain.

Conclusion

The ASPN Back Guideline represents the first comprehensive analysis and grading of the existing and emerging interventional treatments available for low back pain. This will be a living document which will be periodically updated to the current standard of care based on the available evidence within peer-reviewed literature.

Three generations of treatments for osteoporotic vertebral fractures: what is the evidence?

The management of vertebral compression fractures (VCFs) is based on conservative treatment and minimally invasive vertebral augmentation procedures. However, the role of vertebral augmentation is now being questioned by clinical trials and extensive studies. The aim of this review is to report the most relevant evidences on effectiveness, safety, and indications of the currently available vertebral augmentation techniques. Conservative treatment with bracing is effective in reducing acute but it has no effect on segmental kyphosis progression and pseudoarthrosis can occur. Percutaneous vertebroplasty (PV) was the first vertebral augmentation technique to be proposed for the treatment of VCFs. Two blinded and randomized clinical trials compared PV to a sham procedure and no significant differences in terms of efficacy were reported. More recent studies have suggested that PV can still benefit patients with acute VCFs and severe pain at onset. Balloon kyphoplasty (BK) was developed to improve the segmental alignment restoring the height of collapsed vertebrae. BK allows similar pain relief and disability improvement, as well as greater kyphosis correction compared to PV, moreover BKP seems to reduce cement leakage. Vertebral body stenting (VBS) and the KIVA system are third generation techniques of vertebral augmentation. VBS aims to increase the effectiveness in restoring the segmental alignment, while the KIVA system can prevent cement leakage. These techniques are effective and safe, even if their superiority to BK has yet to be proven by studies with a high level of evidence.

[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.

Therapeutic Efficacy of Third-Generation Percutaneous Vertebral Augmentation System (PVAS) in Osteoporotic Vertebral Compression Fractures (OVCFs): A Systematic Review and Meta-analysis

Purpose

This study aimed to assess whether the third-generation PVAS was superior to percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) in treating patients with OVCFs.

Methods

Databases, including Pubmed, Embase, and Cochrane library, were searched to identify relevant interventional and observational articles in vivo or in vitro comparing the third-generation PVAS to PVP/PKP in OVCFs patients. A meta-analysis was performed under the guidelines of the Cochrane Reviewer's Handbook.

Results

11 in vivo articles involving 1035 patients with 1320 segments of diseased vertebral bodies and 8 in vitro studies enrolling 40 specimens with 202 vertebral bodies were identified. The vivo studies indicated no significant differences were found in visual analog scale (VAS), Oswestry Disability Index (ODI), operation time, or injected cement volume (P > 0.05). The third-generation PVAS was associated with significant improvement in vertebral height and Cobb angle (P < 0.05) and also with a significantly lower risk of cement leakages and new fractures (P < 0.05). The vitro studies suggest that the third-generation PVAS was associated with better anterior vertebral height (AVH) and kyphotic angle (KA) after deflation and cement. No significant differences were found in stiffness or failure load after cement between the two groups (P > 0.05).

Conclusion

Based on current evidence, although providing similar improvement in VAS and ODI, the third-generation PVAS may be superior to PVP/PKP in local kyphosis correction, vertebral height maintenance, and adverse events reduction. Further high-quality randomized studies are required to confirm these results.

Influence of Industry in Hydrocephalus and Vertebral Augmentation Literature

OBJECTIVE

To investigate whether financial bias exists in hydrocephalus and vertebral augmentation literature.

METHODS

A systematic literature search was performed in PubMed of studies concerning vertebral augmentation and cerebrospinal fluid valves. The relationship between reported conflicts of interest and the nature of the conclusion (positive vs. neutral and negative) was analyzed.

RESULTS

Having a conflict of interest was significantly associated with reporting a positive conclusion in studies investigating valves for hydrocephalus (92.3% positive conclusion vs. 36.4%; P = 0.001), but not for cement augmentation studies (80.5% positive conclusion vs. 65.7%; P = 0.087). As studies concerning vertebral augmentation implants had only positive conclusions, no analysis could be performed.

CONCLUSIONS

Our findings suggest a positive relationship between reported conflict of interest and positive outcome in neurosurgical literature concerning cerebrospinal fluid valves.

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.

INTRAVERTEBRAL EXPANDABLE IMPLANTS IN THORACOLUMBAR VERTEBRAL COMPRESSION FRACTURES

Current scientific evidence enhances the importance of the anatomic restauration of vertebral bodies with compression fractures aiming, as with other human body joints, to obtain a biomechanic and functional spine as close as the one prior to the fracture as possible. We consider that anatomic reduction of these fractures is only completely possible using intravertebral expandable implants, restoring vertebral endplate morphology, and enabling a more adequate intervertebral disc healing. This enables avoiding disc and osteodegenerative changes to that vertebral segment and its adjacent levels, as well as the anterior overload of adjacent vertebral bodies in older adults - a consequence of post-traumatic vertebral flattening - thus minimizing the risk of adjacent vertebral fractures. The ability of vertebral body fracture reduction and height maintenance over time and its percutaneous transpedicular application make the intra-vertebral expandable implants a very attractive option for treating these fractures. The authors show the direct and indirect reduction concepts of vertebral fractures, review the biomechanics, characteristics and indications of intravertebral expandable implants and present a suggestion for updating the algorithm for the surgical treatment of vertebral compression fractures which includes the use of intravertebral expandable implants. Level of Evidence V, Expert Opinion.

Treating traumatic thoracolumbar spine fractures using minimally invasive percutaneous stabilization plus balloon kyphoplasty: a 102-patient series

BACKGROUND

There is no consensus on the treatment for spinal injuries resulting in thoracolumbar fractures without neurological impairment. Many trauma centers are opting for open surgery rather than a neurointerventional approach combining posterior percutaneous short fixation (PPSF) plus balloon kyphoplasty (BK).

OBJECTIVE

To assess the safety and efficacy of PPSF+BK and to estimate the expected improvement by clarifying the factors that influence improvement.

METHODS

We retrospectively reviewed patients who underwent PPSF+BK for the treatment of single traumatic thoracolumbar fractures from 2007 to 2019. Kyphosis, loss of vertebral body height (VBH), clinical and functional outcomes including visual analog scale and Oswestry disability index were assessed. We examined the overall effects in all patients by constructing a linear statistical model, and then examined whether efficacy was dependent on the characteristics of the patients or the fractures.

RESULTS

A total of 102 patients were included. No patient experienced neurological worsening or wound infections. The average rates of change were 74.4% (95% CI 72.6% to 76.1%) for kyphosis and 85.5% (95% CI 84.4% to 86.6%) for VBH (both p<0.0001). The kyphosis treatment was more effective on Magerl A3 and B2 fractures than on those classified as A2.3, as well as for fractures with slight posterior wall protrusion on the spinal canal. A higher postoperative visual analog scale score was predictive of poorer outcome at 1 year.

CONCLUSIONS

This is the largest series reported to date and confirms and validates this surgical treatment. All patients exhibited improved kyphosis and restoration of VBH. We advise opting for this technique rather than open surgery.

Vertebral balloon kyphoplasty versus vertebral body stenting in non-osteoporotic vertebral compression fractures at the thoracolumbar junction: a comparative radiological study and finite element analysis (BONEXP study)

OBJECTIVE

To compare radiologically balloon kyphoplasty (BKP) and vertebral compression fracture (VCF) expansion and corroborate with a finite element (FE) analysis. The principle of BKP is to stabilize VCF by restoring vertebral body anatomy using bone expansion and cement filling. More recently, vertebral body stenting (VBS) has been developed to reduce the loss of vertebral height observed after balloon deflation.

METHODS

A retrospective, monocentric and continuous study of 60 non-osteoporotic fractures of the thoracolumbar junction treated by vertebral bone expansion was carried out over three years. The main endpoint was radiological correction of vertebral kyphosis (VK) at 3 months. The other studied parameters were vertebral height, index of Farcy, index of Beck, cement leakages and their location. A FE model was developed to analyze effects linked to the stent during cement injection, specifically throughout the risk of cement leakage evaluation.

RESULTS

After three months, average reduction of VK was 4.73° ± 4.8° after BKP, and 4.63° ± 2.7° after VBS. There was no difference between the two techniques, but cement leakage was significantly greater with BKP (41.7%) than with VBS (4.2%). FE analysis showed substantial changes of the cement flow orientation in the presence of a stent.

CONCLUSION

BKP and VBS offer comparable expansion with no added value of VBS in non-osteoporotic VCF reduction. VBS technique appears to prevent cement leakage due to its mesh architecture hindering the leaking process. In counterpart, such balloon expansion is likely to require higher pressure to deploy the stent. This could be an important parameter to take into account in young patients with high bone density.

Efficacy of a Novel Vertebral Body Augmentation System in the Treatment of Patients with Symptomatic Vertebral Body Fractures

Purpose

To evaluate the safety and efficacy of a novel augmentation implant in the treatment of patients with symptomatic vertebral body fractures.

Materials and Methods

Thirty consecutive patients (seven males and 23 females), mean age of 70 years (range 56 to 89) with osteoporotic fractures and/or low-energy trauma fractures (osteoporosis confirmed by CT), were enrolled in an IRB-approved prospective study. The type of fracture was classified according to the Magerl classification. The patients were treated with the Tektona^® dedicated vertebral body augmentation system. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores were obtained after 1, 6 and 12 months. Quality of life was assessed with the SF36 score.

Results

A total of 37 vertebral bodies, mostly from T6 to L5, were treated in the 30 enrolled patients. In 67.6% of the cases (n = 25), lumbar fractures were treated. Most of the fractures (43%; n = 16) were A1.1 according to the Magerl classification. A significant pain reduction evaluated by VAS scores (p < 0.0001) was observed on average 7.6 (before the procedure) to 2.8 (immediately post-treatment), 2.1 and 2.7 (after 6 and 12 months later, respectively). The mean ODI score was 55.5% before treatment, and this was statistically significant reduced to 22.3% and 26.9%, respectively, at 6 and 12 months after treatment (p < 0.0001). The SF36 scores, both physical and mental components, showed statistically significant variations (p < 0.0001) whose direction was subpopulation dependent.

Conclusion

Patients with confirmed osteoporosis, suffering from symptomatic vertebral body fractures (osteoporotic and/or low-energy traumatic), were treated safely and effectively using this novel implant.

An Assessment of Randomized Controlled Trial Quality in The Journal of Bone & Joint Surgery: Update from 2001 to 2013

BACKGROUND

The quality of reporting of randomized controlled trials (RCTs) published in The Journal of Bone & Joint Surgery (JBJS) from 1988 to 2000 was previously analyzed. The purpose of this current study was to analyze the quality of reporting of RCTs published in JBJS from 2001 to 2013 to identify trends over time and potential areas of improvement for future clinical trials.

METHODS

A manual search of the JBJS database identified RCTs published between January 2001 and December 2013. Quality assessments, using the Detsky quality-of-reporting index (Detsky score), a modified Cochrane risk-of-bias tool, and abstraction of relevant data identifying predictors of quality, were conducted.

RESULTS

A total of 5,780 publications were identified in JBJS from 2001 to 2013, with 285 RCTs (4.9%), representing an increase from the prior 13-year period. The overall mean transformed Detsky score (and standard error) increased significantly (p < 0.001) from 68.1% ± 1.67% to 76.24% ± 0.72%. The percentage of multicenter RCTs decreased from 67% to 31%. The percentage of positive trials also decreased from 80% to 50.5%, as did the mean sample size (212 to 166). Regression analysis indicated that trials with an epidemiologist as the first author and nonsurgical trials were significantly associated (p = 0.001) with a higher overall trial quality score. The categories of the lowest mean methodology scores were randomization and concealment, eligibility criteria, and reasons for patient exclusion, as identified with the Detsky score, and patient and assessor blinding, as identified with the risk-of-bias assessment.

CONCLUSIONS

The quantity and quality of published RCTs in JBJS have increased in the 2001 to 2013 time period compared with the previous time period. Although these improvements are encouraging, trends to smaller, single-center trials were also observed. To efficiently determine the efficacy of orthopaedic treatments and limit bias, high-quality randomized trials of appropriate sample size and rigorous design are needed.

Vertebral augmentation with spinal implants: third-generation vertebroplasty

This article is to review the different types of vertebral augmentation implants recently becoming available for the treatment of benign and malignant spinal compression fractures. After a detailed description of the augmentation implants, we review the available clinical data. We will conclude with a summary of the advantages and disadvantages of vertebral implants and how they can affect the future treatment options of compression fractures.

Vertebral fragility fractures: clinical and radiological results of augmentation and fixation-a systematic review of randomized controlled clinical trials

AIM

To assess the outcome of augmentation techniques, i.e., percutaneous vertebroplasty (PVP), balloon kyphoplasty (BKP), vertebral body stenting (VBS) and fixation techniques in the management of vertebral fragility fractures (VFFs).

METHODS

OVID-MEDLINE^®, EMBASE, Cochrane Library, SCOPUS, Springer Link, Web of Science, Google Scholar and PubMed were searched from January 2009 to February 2019 to identify relevant studies. The methodological qualities of the studies were evaluated and relevant data were extracted.

RESULTS

Thirteen randomized controlled trials, recruiting 1963 patients, were included. PVP, compared with conservative management (CM), showed a greater pain relief and an improved vertebral body height (VBH) restoration. Moreover, PVP revealed superior to a sham procedure for pain relief in acute VFFs. BKP, compared with CM, rapidly reduces pain and improves quality of life without increasing the risk of additional VFFs. BKP, compared with PVP, has fewer cement leakage rates and is more effective in VBH restoration. BKP should also be preferred to VBS, since it is associated with less material-related complications. Pedicle screw fixation associated with PVP, compared with PVP alone, revealed effective in preventing secondary VFFs.

CONCLUSIONS

BKP showed better clinical and radiological outcomes compared with CM and PVP. BKP revealed as effective as VBS in VBH restoration with less material-related complications.

Stent screw-assisted internal fixation (SAIF): clinical report of a novel approach to stabilizing and internally fixating vertebrae destroyed by malignancy

OBJECTIVE

Severe lytic cancerous lesions of the spine are associated with significant morbidity and treatment challenges. Stabilization and restoration of the axial load capability of the vertebral body (VB) are important to prevent or arrest vertebral collapse. Percutaneous stent screw-assisted internal fixation (SAIF), which anchors a VB stent/cement complex with pedicular screws to the posterior vertebral elements, is a minimally invasive, image-guided, 360° internal fixation technique that can be utilized in this patient cohort. The purpose of this study was to assess the feasibility, safety, and stabilization efficacy of VB reconstruction via the SAIF technique in a cohort of patients with extensive lytic vertebral lesions, who were considered to have an unstable or potentially unstable spine according to the Spinal Instability Neoplastic Score (SINS).

METHODS

This study was a retrospective assessment of a prospectively maintained database of a consecutive series of patients with neoplastic extensive extracompartmental osteolysis (Tomita type 4-6) of the VB treated with the SAIF technique. VB reconstruction was assessed on postprocedure plain radiographs and CT by two independent raters. Technical and clinical complications were recorded. Clinical and imaging follow-ups were assessed.

RESULTS

Thirty-five patients with extensive osteolytic metastatic lesions of the VB underwent 36 SAIF procedures. SAIF was performed as a stand-alone procedure in 31/36 cases and was associated with posterior surgical fixation in 5/36 (4/5 with decompressive laminectomy). In 1 case an epidural cement leak required surgical decompression. VB reconstruction was categorized as satisfactory (excellent or good rating) by the two raters in 34/36 cases (94.5%) with an interrater reliability of 94.4% (Cohen's kappa of 0.8). Follow-up, ranging from 1 to 30 months, was available for 30/36 levels. Long-term follow-up (6-30 months, mean 11.5 months) was available for 16/36 levels. Stability during follow-up was noted in 29/30 cases.

CONCLUSIONS

SAIF provides 360° nonfusion internal fixation that stabilizes the VB in patients with extensive lytic lesions that would otherwise be challenging to treat.

Armed Kyphoplasty: An Indirect Central Canal Decompression Technique in Burst Fractures

BACKGROUND AND PURPOSE

Burst fractures are characterized by middle column disruption and may feature posterior wall retropulsion. Indications for treatment remain controversial. Recently introduced vertebral augmentation techniques using intravertebral distraction devices, such as vertebral body stents and SpineJack, could be effective in fracture reduction and fixation and might obtain central canal clearance through ligamentotaxis. This study assesses the results of armed kyphoplasty using vertebral body stents or SpineJack in traumatic, osteoporotic, and neoplastic burst fractures with respect to vertebral body height restoration and correction of posterior wall retropulsion.

MATERIALS AND METHODS

This was a retrospective assessment of 53 burst fractures with posterior wall retropulsion and no neurologic deficit in 51 consecutive patients treated with armed kyphoplasty. Posterior wall retropulsion and vertebral body height were measured on pre- and postprocedural CT. Clinical and radiologic follow-up charts were reviewed.

RESULTS

Armed kyphoplasty was performed as a stand-alone treatment in 43 patients, combined with posterior instrumentation in 8 and laminectomy in 4. Pre-armed kyphoplasty and post-armed kyphoplasty mean posterior wall retropulsion was 5.8 and 4.5 mm, respectively (P < .001), and mean vertebral body height was 10.8 and 16.7 mm, respectively (P < .001). No significant clinical complications occurred. Clinical and radiologic follow-up (1-36 months; mean, 8 months) was available in 39 patients. Three treated levels showed a new fracture during follow-up without neurologic deterioration, and no retreatment was deemed necessary.

CONCLUSIONS

In the treatment of burst fractures with posterior wall retropulsion and no neurologic deficit, armed kyphoplasty yields fracture reduction, internal fixation, and indirect central canal decompression. In selected cases, it might represent a suitable minimally invasive treatment option, stand-alone or in combination with posterior stabilization.

Radiological evaluation of kyphoplasty with an intravertebral expander after osteoporotic vertebral fracture

Spinal deformities due to osteoporotic vertebral compression fractures can be reduced by balloon kyphoplasty, but the correction may be partly lost when the balloon is deflated. The present study aimed to evaluate an intravertebral expander developed to reduce and maintain vertebral body height while cement is injected to correct spinal deformities due to osteoporotic vertebral fractures. The study included 31 osteoporotic vertebral body fractures in 31 patients, classified as A1 according to the AO classification, who underwent kyphoplasty using an intravertebral expander. The kyphosis angle was significantly corrected from 13.4 degrees prior to kyphoplasty to 10.8 degrees (p < 0.01) after surgery, but this correction was lost at 12 months (13.3 degrees). The correction of the kyphosis angle best correlated with the pre-operative mobility of the fracture (r = 0.59, p < 0.01), and the loss of the kyphosis improvement correlated with the amount of correction (r = 0.49, p = 0.01). All patients, except for six with adjacent vertebral fractures, experienced significant pain reduction (VAS 8.7 pre-operatively and 2.0 at 12 months; p < 0.01), and the pain was not affected by the correction of the spinal deformity or the loss of correction in the follow-up period. These results suggest that the mobility of the fracture mainly determines the extent of deformity correction rather the device used for reduction, and greater corrections are at increased risk for losing the improvement. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:457-465, 2019.

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.

Minimally invasive non-fusion vertebral body stabilization in severe benign and malignant fractures. Stent-screw Assisted Internal Fixation: the SAIF technique

This short review focuses on clinical and therapeutic issues posed by severe osteoporotic and neoplastic insufficiency vertebral fractures and on the potential use of a new technique to obtain minimally invasive vertebral body reconstruction, augmentation, and stabilization in such severe fractures, combining two preexisting procedures. The implant of vertebral body stents is followed by insertion of percutaneous, fenestrated, cement-augmented pedicular screws that act as anchors to the posterior elements for the cement–stent complex. This procedure results in a 360° nonfusion form of vertebral internal fixation that may empower vertebral augmentation and potentially avoid corpectomy in challenging osteoporotic and neoplastic fractures.

Stent-screw-assisted internal fixation: the SAIF technique to augment severe osteoporotic and neoplastic vertebral body fractures

Objectives

To describe a new technique to obtain minimally invasive but efficient vertebral body (VB) reconstruction, augmentation, and stabilization in severe osteoporotic and neoplastic fractures, combining two pre-existing procedures. The implant of vertebral body stents (VBS) is followed by insertion of percutaneous, fenestrated, cement-augmented pedicular screws that act as anchors to the posterior elements for the cement/stent complex. The screws reduce the risk of stent mobilization in a non-intact VB cortical shell and bridge middle column and pedicular fractures. This procedure results in a 360° non-fusion form of vertebral internal fixation that may empower vertebral augmentation and potentially avoid corpectomy in challenging fractures.

Procedure details

This report provides step-by-step procedural details, rationale, and proposed indications for this procedure. The procedure is entirely percutaneous under fluoroscopic guidance. Through transpedicular trocars the VBS are inserted, balloon-expanded and implanted in the VB. Over k-wire exchange the transpedicular screws are inserted inside the lumen of the stents and cement is injected through the screws to augment the stents and fuse the screws to the stents.

Applications

This technique may find appropriate applications for the most severe osteoporotic fractures with large clefts, high-degree fragmentation and collapse, middle column and pedicular involvement, and in extensive neoplastic lytic lesions.

Conclusions

Stent-Screw-Assisted Internal Fixation (SAIF) might represent a minimally invasive option to obtain VB reconstruction and restoration of axial load capability in severe osteoporotic and neoplastic fractures, potentially obviating the need for more invasive surgical interventions in situations that would pose significant challenges to standard vertebroplasty or balloon kyphoplasty.

Vertebral body stent augmentation to reconstruct the anterior column in neoplastic extreme osteolysis

BACKGROUND

Extensive lytic lesions of the vertebral body (VB) increase risk of fracture and instability and require stabilization of the anterior column. Vertebral augmentation is an accepted treatment option, but when osteolysis has extensively destroyed the VB cortical boundaries (a condition herein defined as 'extreme osteolysis'), the risk of cement leakage and/or insufficient filling is high. Vertebral body stents (VBSs) might allow partial restoration of VB height, cement containment, and reinforcement, but their use in extreme osteolysis has not been investigated.

OBJECTIVE

To assess retrospectively the feasibility and safety of VBS augmentation in patients with 'extreme osteolysis' of the VB.

METHODS

We retrospectively analyzed 41 treated vertebrae (from T1 to L5). VB reconstruction was assessed on postprocedure CT images and rated on a qualitative 4-point scale (poor-fair-good-excellent). Clinical and radiological follow-up was performed at 1 month and thereafter at intervals in accordance with oncological protocols.

RESULTS

VBS augmentation was performed at 12 lumbar and 29 thoracic levels, with bilateral VBS in 23/41. VB reconstruction was judged satisfactory (good or excellent) in 37/41 (90%) of levels. Bilateral VBS received higher scores than unilateral (p=0.057, Pearson's X²). We observed no periprocedural complications. Cement leaks (epidural or foraminal) occurred at 5/41 levels (12.2%) without clinical consequences. Follow-up data were available for 27/29 patients, extending beyond 6 months for 20 patients (7-28 months, mean 15.3 months). VBS implant stability was observed in 40/41 cases (97.5%).

CONCLUSIONS

Our results support the use of VBS as a minimally invasive, safe and effective option for reconstructing the anterior column in prominent VB osteolysis.

The Role of Minimally Invasive Vertebral Body Stent on Reduction of the Deflation Effect After Kyphoplasty: A Biomechanical Study

STUDY DESIGN

Biomechanical investigation using cadaver spines.

OBJECTIVE

The aim of the present study was to assess the magnitude of the deflation effect after balloon kyphoplasty (BKP) or use of minimally invasive vertebral body stent (MIVBS) in in vitro biomechanical condition.

SUMMARY OF BACKGROUND DATA

BKP is a well-established minimally invasive treatment option for osteoporotic vertebral compression fractures. However, this technique can lead to a secondary height loss-known as the "deflation effect"-causing intrasegmental kyphosis and an overall alignment failure.

METHODS

The study was conducted on 24 human cadaveric vertebral bodies (T12-L5). After creating a compression fracture model, the fractured vertebral bodies were reduced by BKP (n = 12) or by MIVBS (n = 12) and then augmented with polymethyl methacrylate bone cement. Each step of the procedure was performed under fluoroscopic guidance and the results were analyzed quantitatively. Finally, the strength and stiffness of augmented vertebral bodies were measured by biomechanical tests.

RESULTS

Complete initial reduction of the fractured vertebral body height was achieved by both systems. Secondary loss of reduction after balloon deflation was significantly greater in the BKP group (2.36 ± 0.63 mm vs. 0.34 ± 0.43 mm in the MIVBS group; P < 0.05). Height gain was significantly higher in the MIVBS group (77.68% ± 11.46% vs. 34.87% ± 13.16% in the BKP group; P < 0.05). Increase in the kyphotic angle gain (relative to the preoperative kyphotic angle) was significantly more in the MIVBS group (95.60% ± 6.12% vs. 77.0% ± 4.94% in the BKP group; P < 0.05). Failure load was significantly higher in the MIVBS group (189% ± 16% vs. 146% ± 14%; P < 0.05). However, stiffness was not significantly different between the two groups.

CONCLUSION

The deflation effect after BKP can be significantly decreased with the use of the MIVBS technique.

LEVEL OF EVIDENCE

N/A.

Review of Vertebral Augmentation: An Updated Meta-analysis of the Effectiveness

Background

To update vertebral augmentation literature by comparing outcomes between vertebroplasty (VP), balloon kyphoplasty (BKP), vertebral augmentation with implant (VAI), and nonsurgical management (NSM) for treating vertebral compression fractures (VCFs).

Methods

A PubMed literature search was conducted with keywords kyphoplasty, vertebroplasty, vertebral body stent, and vertebral augmentation AND implant for English-language articles from February 1, 2011, to November 22, 2016. Among the results, 25 met the inclusion criteria for the meta-analysis. Inclusion criteria were prospective comparative studies for mid-/lower-thoracic and lumbar VCFs enrolling at least 20 patients. Exclusion criteria included studies that were single arm, systematic reviews and meta-analyses, traumatic nonosteoporotic or cancer-related fractures, lack of clinical outcomes, or non-Level I and non-Level II studies. Standardized mean difference between baseline and end point for each outcome was calculated, and treatment groups were pooled using random effects meta-analysis.

Results

Visual analog scale pain reduction for BKP and VP was -4.05 and -3.88, respectively. VP was better than but not significantly different from NSM (-2.66), yet BKP showed significant improvement from both NSM and VAI (-2.77). The Oswestry Disability Index reduction for BKP showed a significant improvement over VAI (P < .001). There was no significant difference in changes between BKP and VP for anterior (P = .226) and posterior (P = .293) vertebral height restoration. There was no significant difference in subsequent fractures following BKP (32.7%; 95% confidence interval [CI]: 8.8%-56.6%) or VP (28.3%; 95% CI: 7.0%-49.7%) compared with NSM (15.9%; 95% CI: 5.2%-26.6%).

Conclusions/Level of Evidence

Based on Level I and II studies, BKP had significantly better and VP tended to have better pain reduction compared with NSM. BKP tended to have better height restoration than VP. Additionally, BKP had significant improvements in pain reduction and disability score as compared with VAI.

Clinical Relevance

This meta-analysis serves to further define and support the safety and efficacy of vertebral augmentation.

Is vertebral body stenting in combination with CaP cement superior to kyphoplasty?

PURPOSE

In the evolution of the minimally invasive treatment of vertebral compression fractures, vertebral body stenting (VBS) was developed to reduce intraoperative and secondary loss of vertebral height. Particularly in combination with the usage of biodegradable cement, the influence of VBS on the rate of intraoperative complications and long-term outcome is unclear. The purpose of this study was to investigate the differences between balloon kyphoplasty (BKP) and VBS regarding their long-term clinical and radiological outcome in combination with calcium phosphate (CaP) application instead of polymethyl methacrylate (PMMA).

METHODS

This retrospective study included 49 patients with fresh mono-segmental thoracolumbar fractures without neurological signs treated with VBS or BKP and CaP cement (Calcibone). The outcome was evaluated with the visual analogue pain scale (VAS), the Oswestry disability score (ODI), and radiologically assessed.

RESULTS

In the course of the radiological follow-up, the VBS group showed statistically significant less vertebral height loss than the BKP group. However, with respect to VAS and ODI scores there were no statistically significant differences between the VBS and BKP group in the clinical follow-up. The rate of cement leakage was comparable in both groups.

CONCLUSIONS

Both techniques facilitated good clinical results in combination with absorbable cement augmentation. In particular, the VBS enabled us to benefit from the advantages of the resorbable isothermic CaP cement with an improved radiological outcome in the long term compared to BKP. However, there was a mentionable loss of reduction in the follow-up in both groups compared to previously published data with PMMA cement. These slides can be retrieved under Electronic Supplementary Material.

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.

Combined anteroposterior fixation using a titanium cage versus solely posterior fixation for traumatic thoracolumbar fractures: A systematic review and meta-analysis

Study Design:

Systematic review with meta-analysis.

Objective:

Additional anterior stabilization might prevent posterior implant failure, but over time, the disadvantageous of bone grafts have become evident. The objective of this systematic review was to compare risks and advantages of additional anterior stabilization with a titanium cage to solely posterior fixation for traumatic thoracolumbar fractures.

Methods:

An electronic search was performed in the literature from 1980 to March 2016. Studies comparing only posterior with anteroposterior fixation by means of a titanium cage were included in this study. Data extraction and Cochrane risk of bias assessment were done by two independent authors. In addition, the PRISMA statement was followed, and the GRADE approach was used to present results.

Results:

Of the 1584 studies, two randomized controlled trials (RCTs) and one retrospective cohort study were included in the meta-analysis. The RCTs reported evidence of high quality that anteroposterior stabilization maintained better kyphosis correction than posterior stabilization alone. However, these results were neutralized in the meta-analysis by the cohort study. Implant failure was reported by one study, in the posterior group. No differences in follow-up visual analog scale scores, neurologic improvement, and complications were found. Operation time, blood loss, and hospital stay all increased in the anteroposterior group.

Conclusions:

Patients with a highly comminuted or unstable fracture could benefit from combined anteroposterior stabilization with a titanium cage, for some evidence suggests this prevents loss of correction. However, large randomized studies still lack. There is a risk of cage subsidence, and increased perioperative risks have to be considered when choosing the optimal treatment.

Pain, Quality of Life, and Safety Outcomes of Kyphoplasty for Vertebral Compression Fractures: Report of a Task Force of the American Society for Bone and Mineral Research

The relative efficacy and harms of balloon kyphoplasty (BK) for treating vertebral compression fractures (VCF) are uncertain. We searched multiple electronic databases to March 2016 for randomized and quasi-randomized controlled trials comparing BK with control treatment (nonsurgical management [NSM], percutaneous vertebroplasty [PV], KIVA VCF treatment system [Benvenue Medical, Inc., Santa Clara, CA, USA], vertebral body stenting, or other) in adults with VCF. Outcomes included back pain, back disability, quality of life, new VCF, and adverse events (AEs). One reviewer extracted data, a second checked accuracy, and two rated risk of bias (ROB). Mean differences and 95% confidence intervals (CIs) were calculated using inverse-variance models. Risk ratios of new VCF and AE were calculated using Mantel-Haenszel models. Ten unique trials enrolled 1837 participants (age range, 61 to 76 years; 74% female), all rated as having high or uncertain ROB. Versus NSM, BK was associated with greater reductions in pain, back-related disability, and better quality of life (k = 1 trial) that appeared to lessen over time, but were less than minimally clinically important differences. Risk of new VCF at 3 and 12 months was not significantly different (k = 2 trials). Risk of any AE was increased at 1 month (RR = 1.73; 95% CI, 1.36 to 2.21). There were no significant differences between BK and PV in back pain, back disability, quality of life, risk of new VCF, or any AE (k = 1 to 3 trials). Limitations included lack of a BK versus sham comparison, availability of only one RCT of BK versus NSM, and lack of study blinding. Individuals with painful VCF experienced symptomatic improvement compared with baseline with all interventions. The clinical importance of the greater improvements with BK versus NSM is unclear, may be due to placebo effect, and may not counterbalance short-term AE risks. Outcomes appeared similar between BK and other surgical interventions. Well-conducted randomized trials comparing BK with sham would help resolve remaining uncertainty about the relative benefits and harms of BK. © 2017 American Society for Bone and Mineral Research.

Third-generation percutaneous vertebral augmentation systems

Currently, there is no general consensus about the management of osteoporotic vertebral fractures (OVF). In the past, conservative treatment for at least one month was deemed appropriate for the majority of vertebral fractures. When pain persisted after conservative treatment, it was necessary to consider surgical interventions including: vertebroplasty for vertebral fractures with less than 30% loss of height of the affected vertebral body and kyphoplasty for vertebral fractures with greater than 30% loss of height. Currently, this type of treatment is not feasible. Herein we review the characteristics and methods of operation of three of the most common percutaneous vertebral augmentation systems (PVAS) for the treatment of OVF: Vertebral Body Stenting(®) (VBS), OsseoFix(®) and Spine Jack(®). VBS is a titanium device accompanied by a hydraulic (as opposed to mechanical) working system which allows a partial and not immediate possibility to control the opening of the device. On the other hand, OsseoFix(®) and Spine Jack(®) are accompanied by a mechanical working system which allows a progressive and controlled reduction of the vertebral fracture. Another important aspect to consider is the vertebral body height recovery. OsseoFix(®) has an indirect mechanism of action: the compaction of the trabecular bone causes an increase in the vertebral body height. Unlike the Vertebral Body Stenting(®) and Spine Jack(®), the OsseoFix(®) has no direct lift mechanism. Therefore, for these characteristics and for the force that this device is able to provide. In our opinion, Spine Jack(®) is the only device also suitable for the treatment OVF, traumatic fracture (recent, old or inveterate) and primary or secondary bone tumors.

Stentoplasty effectiveness and safety for the treatment of osteoporotic vertebral fractures: a systematic review

To assess the effectiveness and safety of stentoplasty in people with osteoporotic vertebral body fractures. A systematic search of databases including MEDLINE, EMBASE and Cochrane library, between others, was conducted to June 9, 2014. Clinical trials and observational studies that included alive adults with osteoporotic vertebral body fractures and the comparators were the intervention himself, vertebroplasty or balloon kyphoplasty were selected. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies, assessed risk of bias and extracted data. Forty-two citations were identified during the search. After removing duplicates, five studies were included: two clinical trials and three observational studies. Stentoplasty, showed higher rate of adverse events related to material (P=0.043) and cuff pressure (P=0.014) in comparison to kyphoplasty. There was no difference between two procedures in terms of reduction of kyphosis, time of exposure to radiation or postoperative loss of cement. Stentoplasty in comparison to vertebroplasty, showed an improvement of restoration of vertebral height (P=0.042), kyphosis correction and volume of bone cement. No differences were found between two procedures in terms of loss of vertebral body volume. Based on observational studies, stentoplasty improved vertebral height, pain and functional disability at 6 and 12months follow-up, and corrected the angle vertebral fractures in patients with osteoporotic vertebral body. Stentoplasty was presented as a safe procedure in short-medium term, with a low complication rate, a reduced loss of cement and new vertebral body fractures lower rates. Stentoplasty improves vertebral height, reduces the pain and functional disability and correct the vertebral angle in patients with osteoporotic vertebral body fracture with minimum adverse events. Stentoplasty is comparable to kyphoplasty in terms of correction of kyphosis, time of exposure to radiation and cement postoperative loss, and comparable to vertebroplasty in terms of restoration of vertebral height correction and bone cement volume.

LEVEL OF EVIDENCE

Level II systematic review.

Interventional therapies for chronic low back pain

OBJECTIVE

Low back pain (LBP) is a highly prevalent condition and one of the leading causes of lost productivity and health-care costs. The objective of this review is to discuss the role of interventional pain procedures and evidence of their effectiveness in treatment of chronic LBP.

METHODS

This is a narrative review examining published studies on interventional procedures for LBP. The rationales, indications, technique, evidence, and complications for the interventional procedures are discussed.

RESULTS

Interventional pain procedures are used extensively in diagnosis and treatment of chronic pain. LBP is multifactorial, and while significant progress has been made in understanding its pathophysiology, this has not resulted in a proportional improvement of functional outcomes. For certain procedures, such as spinal cord stimulation, medical branch blocks and radiofrequency ablations, and epidural steroid injections for radiculopathy, safety, efficacy, and cost-effectiveness in treating LBP have been well studied. For others, such as interventions for discogenic pain, treatment successes have been modest at best.

CONCLUSIONS

Implementation of interventional pain procedures in the treatment framework of LBP has resulted in improvement of pain intensity in at least the short and medium terms, but equivocal results have been observed in functional improvement.

Safety of balloon kyphoplasty in the treatment of osteoporotic vertebral compression fractures in Europe: a meta-analysis of randomized controlled trials

PURPOSE

The study aims to evaluate the safety of balloon kyphoplasty in the treatment of painful osteoporotic vertebral compression fractures in Europe.

METHODS

Systematic review of the literature, until September 2013, and meta-analysis of randomized controlled trials performed in Europe assessing the safety of balloon kyphoplasty in patients with symptomatic osteoporotic vertebral fractures. Outcomes sought include cement leaks, serious clinical complications and new vertebral fractures.

RESULTS

Six randomized controlled trials fulfilled the inclusion criteria. These studies included data on 525 treated levels in 424 patients. Cement leakages were detected in 18.3 % (95 % CI 11.6, 23.0) of fractures intervened. In about 0.5 % (95 % CI 0.1, 1.1) of fractures leakages proved to be symptomatic. Serious clinical complications were recorded in 11.5 % (95 % CI 1.1, 21.7) of patients treated with balloon kyphoplasty with several of these cases requiring intensive treatment or postoperative surgery. New vertebral fractures were detected in 20.7 % (95 % CI 0.4, 40.9) of patients treated but rates showed an upward pattern when the follow-up period increased. In 54 % of such cases, the fractures were located in regions adjacent to the treated level.

CONCLUSIONS

The safety profile and associated complications of balloon kyphoplasty shown in this analysis, based on the evidence provided by existing randomized controlled trials, can be of help to the practicing clinician who must contrast them with the potential benefits of the technique. These data represent an important step towards a balanced evaluation of the intervention though, a better reporting and more reliable data on long-term assessment of potential sequelae are needed.

Two-year results of vertebral body stenting for the treatment of traumatic incomplete burst fractures

PURPOSE

Vertebral body stenting (VBS) was developed to prevent loss of reduction after balloon deflation during kyphoplasty. The aim of this study is the radiological and clinical mid-term evaluation of traumatic incomplete burst fractures treated by vertebral body stenting.

MATERIAL AND METHODS

This retrospective study included patients with traumatic thoracolumbar incomplete burst fractures treated with VBS between 2009 and 2010. The outcome was evaluated with the visual analogue pain scale (VAS), the Oswestry Disability Score (ODI), the SF-36 Health Survey and radiologically assessed.

RESULTS

Eighteen patients with an average age of 74.8 years were treated with VBS. Twelve were female and six were male. Two years after the operation the ODI and SF-36 showed a moderate limitation of daily activities and quality of life without neurological deficits. VBS restored the vertebral kyphosis by 3.2° and segmental kyphosis by 5°. A minor sintering was observed at follow-up losing 0.8° vertebral kyphosis and 2.1° segmental kyphosis correction. Two asymptomatic cement leakages were detected.

CONCLUSION

VBS provides clinical outcomes comparable with BKP. The stent allows a reconstruction of the anterior column with reduced subsequent loss of correction.

Cement augmentation in a thoracolumbar fracture model: reduction and stability after balloon kyphoplasty versus vertebral body stenting

STUDY DESIGN

In vitro biomechanical investigation.

OBJECTIVE

To assess differences in kyphosis after balloon kyphoplasty (BKP) or vertebral body stenting (VBS).

SUMMARY OF BACKGROUND DATA

Cement augmentation techniques allow early mobilization in patients with osteoporotic thoracolumbar fractures. Biomechanically, the grade of reduction and preservation are as important as in nonosteoporotic fractures. With BKP, negative effects of balloon deflation on the reduction and whether specific combinations of materials may preserve the reduction are as yet unclear.

METHODS

Twelve bisegmental human thoracolumbar specimens (6×T12-L2, 6×L3-L5; age at death, 76.3 yr; range, 63-89 yr; female:male ratio, 3:3; bone mineral density, 68.1 g/cm; mean, 12.9 g/cm) were tested in a spine simulator with pure moments of 7.5 Nm to assess primary and secondary stability. After flexibility testing of the intact specimens, an eccentric compression force induced standardized fractures, which were reduced using either BKP or VBS against a flexional moment of 2.5 Nm. Primary and secondary stability were assessed using range of motion in a spine tester. The specimens were tested after each of 3 periods of cyclic flexion loading. The kyphotic angle of the index vertebra was measured radiographically.

RESULTS

The 2 techniques achieved comparable reduction against a relatively high bending moment in this model. Neither technique restored the stability of the intact state; with increasing loads, the range of motion continuously increased to the level of fractured specimen to the level of the fractured specimen. Although the deflation effect on the kyphotic angle was lower with VBS (P≤0.05), there were no significant differences between the techniques relative to angle restoration.

CONCLUSION

Both augmentation techniques are able to restore vertebral body height after thoracolumbar fractures. The deflation effect on the kyphotic angle was less with VBS than with BKP. High flexion moments during implantation limit the effectiveness of reduction using cement augmentation methods.

LEVEL OF EVIDENCE

N/A.

The past, present and future of minimally invasive spine surgery: a review and speculative outlook

In the last 25 years of spinal surgery, tremendous improvements have been made. The development of smart technologies with the overall aim of reducing surgical trauma has resulted in the concept of minimally invasive surgical techniques. Enhancements in microsurgery, endoscopy and various percutaneous techniques, as well as improvement of implant materials, have proven to be milestones. The advancement of training of spine surgeons and the integration of image guidance with precise intraoperative imaging, computer- and robot-assisted treatment modalities constitute the era of reducing treatment morbidity in spinal surgery. This progress has led to the present era of preserving spinal function. The promise of the continuing evolution of spinal surgery, the era of restoring spinal function, already appears on the horizon. The current state of minimally invasive spine surgery is the result of a long-lasting and consecutive development of smart technologies, along with stringent surgical training practices and the improvement of instruments and techniques. However, much effort in research and development is still mandatory to establish, maintain and evolve minimally invasive spine surgery. The education and training of the next generation of highly specialized spine surgeons is another key point. This paper will give an overview of surgical techniques and methods of the past 25 years, examine what is in place today, and suggest a projection for spine surgery in the coming 25 years by drawing a connection from the past to the future.

Risks and benefits of percutaneous vertebroplasty or kyphoplasty in the management of osteoporotic vertebral fractures

Vertebral fracture (VF) is the most common osteoporotic fracture and is associated with high morbidity and mortality. Conservative treatment combining antalgic agents and rest is usually recommended for symptomatic VFs. The aim of this paper is to review the randomized controlled trials comparing the efficacy and safety of percutaneous vertebroplasty (VP) and percutaneous balloon kyphoplasty (KP) versus conservative treatment. VP and KP procedures are associated with an acceptable general safety. Although the case series investigating VP/KP have all shown an outstanding analgesic benefit, randomized controlled studies are rare and have yielded contradictory results. In several of these studies, a short-term analgesic benefit was observed, except in the prospective randomized sham-controlled studies. A long-term analgesic and functional benefit has rarely been noted. Several recent studies have shown that both VP and KP are associated with an increased risk of new VFs. These fractures are mostly VFs adjacent to the procedure, and they occur within a shorter time period than VFs in other locations. The main risk factors include the number of preexisting VFs, the number of VPs/KPs performed, age, decreased bone mineral density, and intradiscal cement leakage. It is therefore important to involve the patients to whom VP/KP is being proposed in the decision-making process. It is also essential to rapidly initiate a specific osteoporosis therapy when a VF occurs (ideally a bone anabolic treatment) so as to reduce the risk of fracture. Randomized controlled studies are necessary in order to better define the profile of patients who likely benefit the most from VP/KP.

Less invasive reduction and fusion of fresh A2 and A 3 traumatic L 1-L 4 fractures with a novel vertebral body augmentation implant and short pedicle screw fixation and fusion

The aim of this clinical study was to report on the efficacy in reduction and safety in PMMA leakage of a novel vertebral augmentation technique with PEEK and PMMA, together with pedicle screws in the treatment of fresh vertebral fractures in young adults. Twenty consecutive young adults aged 45 ± 11 years with fresh burst A3/AO or severely compressed A2/AO fractures underwent via a less invasive posterior approach one-staged reduction with a novel augmentation implant and PMMA plus 3-vertebrae pedicle screw fixation and fusion. Radiologic parameters as segmental kyphosis (SKA), anterior (AVBHr) and posterior vertebral body height ratio (PVBHr), spinal canal encroachment (SCE), cement leakage and functional parameters as VAS, SF-36 were measured pre- and post-operatively. Hybrid construct restored AVBHr (P < 0.000), PVBHr (P = 0.02), SKA (P = 0.015), SCE (P = 0.002) without loss of correction at an average follow-up of 17 months. PMMA leakage occurred in 3 patients (3 vertebrae) either anteriorly to the fractured vertebral body or to the adjacent disc, but in no case to the spinal canal. Two pedicle screws were malpositioned (one medially, one laterally to the pedicle at the fracture level) without neurologic sequelae. Solid posterolateral spinal fusion occurred 8-10 months post-operatively. Pre-operative VAS and SF-36 scores improved post-operatively significantly. This study showed that this novel vertebral augmentation technique using PEEK implant and PMMA reduces and stabilizes via less invasive technique A2 and A3 vertebral fractures without loss of correction and leakage to the spinal canal.

SPECT/CT for imaging of the spine and pelvis in clinical routine: a physician's perspective of the adoption of SPECT/CT in a clinical setting with a focus on trauma surgery

Injuries of the axial skeleton are an important field of work within orthopaedic surgery and traumatology. Most lesions following trauma may be diagnosed by means of conventional plain radiography, computed tomography or magnetic resonance imaging. However, for some aspects SPECT/ CT can be helpful even in a trauma setting. In particular, the combination of highly sensitive but nonspecific scintigraphy with nonsensitive but highly specific computed tomography makes it particularly useful in anatomically complex regions such as the pelvis and spine. From a trauma surgeon's point of view, the four main indications for nuclear medicine imaging are the detection of (occult) fractures, and the imaging of inflammatory bone and joint diseases, chronic diseases and postoperative complications such as instability of instrumentation or implants. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical setting.

Radiographic and safety details of vertebral body stenting: results from a multicenter chart review

Background

Up to one third of BKP treated cases shows no appreciable height restoration due to loss of both restored height and kyphotic realignment after balloon deflation. This shortcoming has called for an improved method that maintains the height and realignment reached by the fully inflated balloon until stabilization of the vertebral body by PMMA-based cementation. Restoration of the physiological vertebral body height for pain relief and for preventing further fractures of adjacent and distant vertebral bodies must be the main aim for such a method. A new vertebral body stenting system (VBS) stabilizes the vertebral body after balloon deflation until cementation. The radiographic and safety results of the first 100 cases where VBS was applied are presented.

Methods

During the planning phase of an ongoing international multicenter RCT, radiographic, procedural and followup details were retrospectively transcribed from charts and xrays for developing and testing the case report forms. Radiographs were centrally assessed at the institution of the first/senior author.

Results

100 patients (62 with osteoporosis) with a total of 103 fractured vertebral bodies were treated with the VBS system. 49 were females with a mean age of 73.2 years; males were 66.7 years old. The mean preoperative anterior-middle-posterior heights were 20.3-17.6-28.0 mm, respectively. The mean local kyphotic angle was 13.1°. The mean preoperative Beck Index (anterior edge height/posterior edge height) was 0.73, the mean alternative Beck Index (middle height/posterior edge height) was 0.63. The mean postoperative heights were restored to 24.5-24.6-30.4 mm, respectively. The mean local kyphotic angle was reduced to 8.9°. The mean postoperative Beck Index was 0.81, the mean alternative one was 0.82. The overall extrusion rate was 29.1%, the symptomatic one was 1%. In the osteoporosis subgroup there were 23.8% extrusions. Within the three months followup interval there were 9% of adjacent and 4% of remote new fractures, all in the osteoporotic group.

Conclusions

VBS showed its strengths especially in realignment of crush and biconcave fractures. Given that fracture mobility is present, the realignment potential is sound and increases with the severity of preoperative vertebral body deformation.