Surgical procedure and initial radiographic results of a new augmentation technique for vertebral compression fractures

The role of kyphoplasty and expandable intravertebral implants in the acute treatment of traumatic thoracolumbar vertebral compression fractures: a systematic review

Purpose

The aim of the study was to assess the role of kyphoplasty and expandable intravertebral implants in the treatment of traumatic vertebral compression fractures.

Design

This is a systematic review.

Methods

A bibliographic search was carried out in the PubMed/MEDLINE database according to PRISMA guidelines regarding kyphoplasty and expandable intravertebral implants in the treatment of traumatic thoracolumbar vertebral fractures.

Results

A total of 611 records were screened. In total, 51 studies were obtained referring to traumatic vertebral fractures treated with kyphoplasty; however, of these, only studies addressing traumatic burst fractures were selected, resulting in 12 studies: 10 about kyphoplasty and 2 regarding armed kyphoplasty. In all studies, there was a statistically significant improvement in clinical and functional parameters, restoration of vertebral height and decreasing of vertebral and segmental kyphosis. Overall, there was only a residual loss of height and a slight increase in kyphosis throughout the follow-up period, while complications consisted essentially of cement leakage, all with no clinical repercussions.

Conclusion

After the discussion, where we address the concepts of direct and indirect reduction, the association of kyphoplasty with pedicle fixation, the potential advantages of expandable intravertebral implants, as well as the vertebral body type of filling in kyphoplasty, it is concluded that kyphoplasty demonstrates favorable outcomes as a method of posterior percutaneous transpedicular access for reconstruction of the anterior column in burst fractures. It allows for the reconstruction of the vertebral body closer to its original anatomy, carried out in a minimally invasive and safe way, which provides a clinical-functional and imaging improvement maintained at the medium-long term.

The Effectiveness of Vertebral Height Restoration Based on the Vertebroplasty Procedure Used to Treat Osteoporotic Vertebral Fractures

OBJECTIVE

Whether the use of a balloon or stent in vertebroplasty for vertebral fractures, such as balloon kyphoplasty (BKP) or vertebral body stenting (VBS), actually contributes to the restoration of postoperative vertebral height is unclear. The aim of the current study was to compare the effectiveness of percutaneous vertebroplasty (PVP), BKP, and VBS in the correction of collapsed vertebrae in patients with painful vertebral fractures.

METHODS

The cases studied involved 34 vertebrae in 28 patients treated with PVP, 43 vertebrae in 38 patients treated with BKP, and 20 vertebrae in 20 patients treated with VBS at Izinkai Takeda General Hospital. Changes in the vertebral height and local kyphosis angle were measured based on standing lumbar radiographs before and after surgery and were compared among the treatment groups.

RESULTS

There were no differences in changes in the height of the anterior wall, middle body, or posterior wall of the treated vertebrae among the 3 treatment groups. The same was true for changes in the local kyphosis angle. The effectiveness of vertebral height restoration depended heavily upon preoperative vertebral instability in all the treatment groups. Correction loss due to balloon deflation effect or balloon sinking was noted with VBS or BKP.

CONCLUSION

BKP and VBS have the advantage of reducing the risk of extravertebral leakage of injected bone cement, but they have a disadvantage in that they are no more effective than PVP in restoring collapsed vertebrae despite the use of a balloon or metal stent.

Comparison of unipedicular and bipedicular kyphoplasty for treating acute osteoporotic vertebral compression fractures in the lower lumbar spine: a retrospective study

BACKGROUND

Unipedicular and bipedicular approaches for percutaneous kyphoplasty are reportedly both effective in treating osteoporotic vertebral compression fractures (OVCFs). However, most studies have reported thoracolumbar fractures, with few reports describing the treatment of the lower lumbar spine. Here, we compared the clinical and radiological results of unipedicular and bipedicular approaches for percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures.

METHODS

We retrospectively reviewed the records of 160 patients who underwent percutaneous kyphoplasty for lower lumbar (L3-L5) osteoporotic vertebral compression fractures between January 2016 and January 2020. Patient characteristics, surgical outcomes, operation time, blood loss, clinical and radiological features, and complications were compared between two groups. Cement leakage, height restoration, and cement distribution were calculated from the radiographs. Visual pain analog scale (VAS) and Oswestry Disability Index (ODI) were calculated before surgery, immediately post-surgery, and 2 years after surgery.

RESULTS

The mean age, sex, body mass index, injury time, segmental distribution, and morphological classification of fractures before surgery did not differ significantly between the groups. The results showed significant improvements in the VAS score, ODI score, and vertebral height restoration in each group (p < 0.05), with no significant differences between the two groups (p > 0.05). The mean operation time and extent of blood loss were lower in the unipedicular group than those in the bipedicular group (p < 0.05). Different types of bone cement leakage were observed in both groups. Leakage rate was higher in the bipedicular group than in the unipedicular group. Patients in the bipedicular group showed greater improvement in bone cement distribution than those in the unipedicular group (p < 0.05).

CONCLUSIONS

The clinical and radiological results of unipedicular percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures in the lower lumbar region were similar to those of bipedicular percutaneous kyphoplasty. However, the unipedicular approach resulted in shorter surgical time, less blood loss, and less bone cement leakage. Thus, the unipedicular approach may be preferable owing to its several advantages.

Percutaneous mesh-container-plasty versus percutaneous kyphoplasty for the treatment of Kümmell's disease: a retrospective cohort study

BACKGROUND

Both percutaneous kyphoplasty (PKP) and percutaneous mesh-container-plasty (PMCP) were important procedures for the treatment of Kümmell's disease. This study aimed to compare the clinical and radiological results of PKP and PMCP for the treatment of Kümmell's disease.

METHODS

This study included patients with Kümmell's disease treated at our center between January 2016 and December 2019. A total of 256 patients were divided into two groups according to the surgical treatment they received. Clinical, radiological, epidemiological, and surgical data were compared between the two groups. Cement leakage, height restoration, deformity correction, and distribution were evaluated. The visual analog scale (VAS), Oswestry Disability Index (ODI), and short-form 36 health survey domains "role-physical" (SF-36 rp) and "bodily pain" (SF-36 bp) were calculated preoperatively, immediately after surgery, and 1-year postoperatively.

RESULTS

The VAS and ODI scores improved in the PKP [preoperative: 6 (6-7), 68.75 ± 6.64; postoperative: 2 (2-3), 23.25 ± 3.50, respectively] (p < 0.05) and the PMCP [preoperative: 6 (5-7), 67.70 ± 6.50; postoperative: 2 (2-2), 22.24 ± 3.55, respectively] groups (p < 0.05). There were significant differences between the two groups. The mean cost in the PKP group was lower than that in the PMCP group (3697 ± 461 vs. 5255 ± 262 USD, p < 0.05). The cement distribution in the PMCP group was significantly higher than that in the PKP group (41.81 ± 8.82% vs. 33.65 ± 9.24%, p < 0.001). Cement leakage was lower in the PMCP group (23/134) than in the PKP group (35/122) (p < 0.05). The anterior vertebral body height ratio (AVBHr) and Cobb's angle improved in the PKP (preoperative: 70.85 ± 16.62% and 17.29 ± 9.78°; postoperative: 80.28 ± 13.02% and 13.05 ± 8.40°, respectively) and PMCP (preoperative: 70.96 ± 18.01% and 17.01 ± 10.53°; postoperative: 84.81 ± 12.96% and 10.76 ± 9.23°, respectively) groups (p < 0.05). There were significant differences in vertebral body height recovery and segmental kyphosis improvement between the two groups.

CONCLUSIONS

PMCP had advantages over PKP in terms of pain relief and functional recovery for the treatment of Kümmell's disease. Moreover, PMCP is more effective than PKP in preventing cement leakage, increasing cement distribution, and improving vertebral height and segmental kyphosis, despite its higher cost.

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.

Height restoration and sustainability using bilateral vertebral augmentation systems for vertebral compression fractures: a cadaveric study

BACKGROUND CONTEXT

The treatment of vertebral compression fractures using percutaneous augmentation is an effective method to reduce pain and decrease mortality rates. Surgical methods include vertebroplasty, kyphoplasty, and vertebral augmentation with implants. A previous study suggested that a titanium implantable vertebral augmentation device (TIVAD) produced superior height restoration compared to balloon kyphoplasty (BKP) but was based on a less clinically relevant biomechanical model. Moreover, the introduction of high pressure balloons and directional instruments may further aid in restoring height.

PURPOSE

The objective was to evaluate three procedures (BKP, BKP w/ Kyphon Assist (KA; directional instruments), and TIVAD) used for percutaneous augmentation of vertebral fractures with respect to height restoration and sustainability post-operatively.

STUDY DESIGN/SETTING

This is an in vitro cadaver study performed in a laboratory setting.

METHODS

Five osteoporotic female human cadaver thoracolumbar spines (age: 63-77 years, T-score: -2.5 to -3.5, levels: T7-S1) were scanned using computed tomography and dissected into 30 two-functional spine units (2FSUs). Vertebral wedge compression fractures were created by reducing the anterior height of the vertebrae by 25% and holding the maximum displacement for 15 minutes. Post-fracture, surgery was performed on each 2FSU with a constant 100 N load. Surgeries included BKP, BKP w/ KA, or TIVAD (n=10 per treatment group). Post-surgery, cyclic loading was performed on each 2FSU for 10,000 cycles at 600 N (walking), followed by 5,000 cycles at 850 N (standing up/sitting down), and 5,000 cycles at 1250 N (lifting a 5-10kg weight from the floor). Fluoroscopic images were taken and analyzed at the initial, post-fracture, post-surgery, and post-loading timepoints. Anterior, central, and posterior heights, Beck Index, and angle between endplates were assessed.

RESULTS

No difference in height restoration was observed among treatment groups (p=.72). Compared to the initial height, post-surgery anterior height was 96.3±8.7% for BKP, 94.0±10.0% for BKP w/ KA, and 95.3±5.8% for TIVAD. No difference in height sustainability in response to 600 N (p=.76) and 850 N (p=.20) load levels was observed among treatment groups. However, after 1250 N loading, anterior height decreased to 93.8±6.8% of the post-surgery height for BKP, 95.9±6.4% for BKP w/ KA, and 86.0±6.6% for TIVAD (p=.02). Specifically, the mean anterior height reduction between post-surgery and post-1250 N loading timepoints was lower for BKP w/ KA compared to TIVAD (p=.02), but not when comparing BKP to TIVAD (p=.07). No difference in Beck Index or angle between endplates was observed at any timepoint among the treatment groups.

CONCLUSIONS

The present study, utilizing a clinically relevant biomechanical model, demonstrated equivalent height restoration post-surgery and at relatively lower-level cyclic loading using BKP, BKP w/ KA, and TIVAD, contrary to results from a previous study. Less anterior height reduction in response to high-level cyclic loading was observed in the BKP w/ KA group compared to TIVAD.

CLINICAL SIGNIFICANCE

All three treatments can restore height similarly after a vertebral compression fracture, which may lead to pain reduction and decreased mortality. BKP w/ KA may exhibit less height loss in higher-demand patients who engage in physical activities that involve increased weight resistance.

Stent-armed kyphoplasty in osteoporotic thoracolumbar fractures-clinical and functional results and a center experience over 10 years

Background

The optimal treatment of osteoporotic vertebral fractures is still a controversial and under discussion topic. Armed kyphoplasty with expansive intravertebral implants is an emerging procedure, which, in theory, it not only makes it possible to achieve instant analgesia, and to get stabilization gains of benefits of kyphoplasty and vertebroplasty, but also, allows for a more effective maintenance of the restored vertebral height.

Methods

A retrospective observational study is presented, in which 30 patients participated, including a total of 33 osteoporotic thoracolumbar compression burst vertebral fractures with involvement of one or both vertebral platforms and of more than one fifth of the posterior wall. These individuals underwent armed kyphoplasty with VBS^® stents (or stentoplasty) filled with bone cement over 10 years (between 2012 and 2022) at the same center. Clinical (visual analogue scale, Oswestry Disability Index and Patient Global Impression of Change) and imaging results (restoration and maintenance of vertebral body heights) achieved were investigated. The mean follow-up time was 4.5 years (range, 1-10 years).

Results

There was a statistically significant improvement in all clinical and functional parameters evaluated, as well as a statistically significant difference in the various vertebral body heights between preoperative and end of follow-up time [increase of 10.7-15.2-5.0 mm (anterior-median-posterior) in the sagittal plane and 6.7-11.6-9.7 mm (right-median-left) in the coronal plane]. There was a statistically significant direct correlation between vertebral heights in the coronal plane, and between the Beck index assessed at the end of the follow-up period and the improvement in functional disability.

Conclusions

The percutaneous transpedicular posterior approach, the ability to anatomically restore the fractured vertebra and to maintain it in the medium-long term, as well as the reduced risk of adverse effects, make stent-armed kyphoplasty a very attractive treatment option for osteoporotic compressive thoracolumbar fractures. A clinical-morphological correlation was demonstrated regarding the surgical treatment of these fractures, it was found that a more effective morphological restoration of vertebral heights in both the sagittal and coronal planes is associated with superior satisfactory clinical functional parameters.

Percutaneous mesh-container-plasty versus percutaneous kyphoplasty in the treatment of malignant thoracolumbar compression fractures: a retrospective cohort study

OBJECTIVE

This study aimed to compare the clinical and radiological results of percutaneous mesh-container-plasty versus percutaneous kyphoplasty in the treatment of malignant thoracolumbar compression fractures.

METHODS

Patients with malignant thoracolumbar compression fractures treated in a single tertiary care center between January 2011 and December 2020 were retrospectively reviewed and included in the study. Ninety-four patients who were diagnosed by pathological biopsy were divided into 2 groups according to the type of surgical treatment: the percutaneous kyphoplasty group (50 patients: 24 male, 26 female; mean age=73.02 ± 7.79 years) and the percutaneous mesh-container-plasty group (44 patients: 21 male, 23 female; mean age=74.68 ± 7.88 years). The epidemiological data, surgical outcomes, and clinical and radiological features were compared between the 2 groups. Cement leakage, height restoration, deformity correction, and cement distribution were calculated from the radiographs. The visual analog scale, Oswestry disability index, Karnofsky performance scale scores, and short-form 36 health survey domains role physi cal and bodily pain were calculated preoperatively, immediately, and 1 year postoperatively.

RESULTS

The visual analog scale score improved from 5 (range=4-6) preoperatively to 2 (range=2-3) immediately postoperatively in the percutaneous kyphoplasty group and from 5 (range=4-6) preoperatively to 2 (range=2-2) immediately postoperatively in the percutane ous mesh-container-plasty group; there was a significant difference between the 2 groups (P=.018). Although Oswestry disability index, Karnofsky performance scale, short-form 36 health survey domains bodily pain and role physical significantly improved in both groups after surgery compared to the preoperative period, there was no significant difference between the 2 groups (P > .05). The mean cost in the percutaneous kyphoplasty group was lower than that in the percutaneous mesh-container-plasty group (5563 ± 439 vs. 6569 ± 344 thousand dollars, P < .05). There was no difference between the cement volume in the 2 groups, and cement distribution in the percutaneous mesh-container-plasty group was higher than that in the percutaneous kyphoplasty group (44.30% ± 10.25% vs. 32.54% ± 11.76%, P < .05). Cement leakage was found to be lesser in the percutaneous mesh-container-plasty group (7/44) than in the percutane ous kyphoplasty group (18/50, P < .05). There were no statistically significant differences in the recovery of vertebral body height and improvement of segmental kyphosis between the 2 groups (P > .05).

CONCLUSION

Percutaneous kyphoplasty and percutaneous mesh-container-plasty both have significant abilities in functional recovery, height restoration, and segment kyphosis improvement in treating malignant thoracolumbar compression fractures. Percutaneous mesh container-plasty may be better able to relieve pain, inhibit cement leakage, and improve cement distribution than percutaneous kypho plasty. However, percutaneous mesh-container-plasty requires a relatively longer procedure and is more expensive than percutaneous kyphoplasty.

LEVEL OF EVIDENCE

Level III, Therapeutic Study.

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.

Efficiency of a novel vertebral body augmentation system (Tektona™) in non-osteoporotic spinal fractures

BACKGROUND

The restauration of the local kyphosis is crucial to thoracolumbar fractures outcomes. Recently, the Tektona™ (Spine Art) system, constituted by a flexible lamella for corporeal reduction has emerged as a promising solution for osteoporotic fractures. However, no study has yet focused on its results on traumatic fractures.

METHODS

A retrospective longitudinal study on prospectively collected data was conducted on 53 patients that had a kyphoplasty by Tektona™, associated or not to percutaneous fixation. The data collected were clinical, surgical and scannographic (measurement of AVH, MVH and PVH (anterior/medium/posterior vertebral height), and RTA (regional traumatic angle) in°), preoperatively, post-operatively and at last follow-up.

RESULTS

Fractures were mainly located at the upper lumbar spine and were AOSpine A3 type for 74%. The mean RTA was 12° in pre-operative, 4° in post-operative (p = 2e- 9), and 8° at the last follow-up (p = 0,01). The mean correction of RTA for the fixation group was - 10 ± 6° versus - 7 ± 4° for the kyphobroplasty alone group (p = 0,006). The mean correction for fractures located at T10-T12 was - 9 ± 3°, - 9 ± 5° for L1, - 8 ± 3° for L2 and - 5 ± 3° for L3-L5 (p = 0,045).

CONCLUSIONS

The Tektona® system appears to be efficient for acute thoraco-lumbar fractures, comparable to other available systems, allowing a real intracorporeal reduction work. Its relevance, especially in the long term needs further investigation. The association of a percutaneous fixation allow to obtain a better correction of the RTA but did not seem to prevent the loss of correction at follow-up.

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.

Expandable Intravertebral Implants: A Narrative Review on the Concept, Biomechanics, and Outcomes in Traumatology

Expandable intravertebral implants are self-expanding devices applied percutaneously by the posterior transpedicular approach. These devices introduce the concept of anatomical restoration of vertebral body endplates and direct anatomical reduction performed from the interior of the vertebral body with a compression fracture. This paper aims to provide a narrative review on the concept, indications, biomechanical characteristics, as well as functional and radiographic outcomes of the main expandable intravertebral implants currently available, in terms of their application to thoracolumbar spine traumatology. To this end, we performed a search in July 2021 on the MEDLINE/PubMed platform with the words "expandable intravertebral implant", "armed kyphoplasty", "Vertebral Body Stenting" or "stentoplasty" and "SpineJack". The search yielded 144 papers, and of those, we included 15 in this review. We concluded that percutaneous transpedicular posterior access, the ability to reduce vertebral body fractures, particularly of the vertebral endplates and to maintain the vertebral body height, makes the application of expandable intravertebral implants an attractive option in the treatment of thoracolumbar vertebral compression fractures. However, more prospective, randomized, and large-scale blinded studies are still warranted, especially comparative studies between treatments and about the preferential use of an expansive implant over others, in order to gain definitive insights into the effectiveness and indications of each of these devices.

Percutaneous mesh-container-plasty for osteoporotic thoracolumbar burst fractures: A prospective, nonrandomized comparative study

OBJECTIVE

This study aimed to compare the clinical and radiological results of percutaneous mesh-container-plasty (PMCP) versus percutaneous kyphoplasty (PKP) in the treatment of osteoporotic thoracolumbar burst fractures.

METHODS

A prospective study of 122 patients with osteoporotic thoracolumbar burst fractures was conducted. The patients were nonrandomly assigned to receive PKP (62; 16 men, 46 women) and PMCP (60; 14 men, 46 women). The epidemiological data, surgical outcomes, and clinical and radiological features were compared between the 2 groups. Cement leakage, height restoration, deformity correction, canal compromise, and cement distribution were calculated from the radiographs. Visual pain analog scale (VAS), the Oswestry disability index (ODI), and short-form 36 health survey domains role physical (SF-36 rp) and bodily pain (SF-36 bp) were calculated before surgery and immediately and 2 years after surgery.

RESULTS

Although VAS, ODI, SF-36 bp, and SF-36 rp scores improved from 7 (6-9), 71.28±16.38, 22 (0-32), and 25 (0-50) preoperatively to 2 (1-3), 20.02±8.97, 84 (84-84), and 75 (75-100) immediately postoperatively in the PMCP group (p<0.05) and from 7 (6-8), 71.40±13.52, 22 (10.5-31.75), and 25 (0-50) preoperatively to 2 (1-3), 21.78±11.21, 84 (84-84), and 75 (75-100) immediately postoperatively in the PKP group (p<0.05), there was no difference between the 2 groups. The mean cost in the PKP group was less than that in the PMCP group ($5109±231 vs. $6699±201, p<0.05). Anterior, middle, and posterior vertebral body height ratios in the PMCP group were greater than those in the PKP group postoperatively (88.44%±3.76% vs. 81.10%±11.78%, 86.15%±3.50% vs. 82.30%±11.02%, and 93.91%±3.01% vs. 91.43%±6.71%, respectively, p<0.05). The Cobb angle in the PMCP group was lower than that in the PKP group postoperatively (6.67°±4.39° vs. 8.99°±4.06°, p<0.05). Cement distribution in the PMCP group was higher than that in the PKP group (30.48%±5.62% vs. 27.18%±4.87%, p<0.05). Cement leakage was observed to be lesser in the PMCP group (2/60) than in the PKP group (10 vs. 62, p<0.05).

CONCLUSION

Both PKP and PMCP treatments seem to have significant ability in pain relief and functional recovery. Despite its higher cost, PMCP treatment may have a better inhibition ability of cement leakage, cement distribution, height restoration, and improvement in segmental kyphosis than PKP treatment for osteoporotic thoracolumbar burst fractures.

LEVEL OF EVIDENCE

Level II, Therapeutic Study.

Vertebral body cemented stents combined with posterior stabilization in the surgical treatment of metastatic spinal cord compression of the thoracolumbar spine

Background

Extensile interventions to provide anterior spinal column support in metastatic spinal cord compression (MSCC) surgery incur added morbidity in this surgically frail group of patients. We present our preliminary results of posterior spinal decompression and stabilization coupled with vertebral body cemented stents for anterior column support in MSCC.

Methods

Fourteen patients underwent posterior spinal decompression and pedicle screw construct along with vertebral body stenting (VBS) technique for reconstruction and augmentation of the vertebral body. The primary in all except one was solid organ malignancy and 10 patients (71%) were treatment naïve. The mean revised Tokuhashi score was 10.7 ± 2.7 and the mean spinal instability neoplastic score was 9.6 ± 1.9. All vertebral body lesions were purely lytic and were associated with a cortical defect in the posterior wall.

Results

A mean 5.3 ± 2.7 ml low-viscosity polymethyl methacrylate bone cement was injected within the stent at each compression level. No cement extrusion posteriorly was noted in any case from intraoperative fluoroscopy or postoperative radiographs. Five patients died at a mean 6.8 months (range 1-15 months), while the remaining patients have a mean survival of 18 months. Neither further revision surgical intervention nor any neurological deterioration was noted in any patient, who all continued to be ambulatory. The mean postoperative Core Outcome Measures Index score for 11 patients was 4.03 (standard deviation 3.11, 95% confidence interval (1.93-6.12).

Conclusion

In lytic vertebral body lesions with posterior wall erosions, cemented VBS technique adds to the surgical armamentarium in MSCC surgery showing promising early results without added complications.

Cone-beam computed tomography guided unipedicular central stentoplasty of the thoracolumbar spine: Early technical experience and results

INTRODUCTION

An unipedicular vertebral body stenting technique, termed 'central stentoplasty', was developed at our institution. With this technique, a single vertebral body stent was deployed percutaneously in the midline of the vertebral body using cone-beam computed tomography (CBCT) guidance.

METHODS

From September 2013 to July 2015, forty-four patients with fifty-six vertebral bodies underwent central stentoplasty. All fractures were of osteoporotic, traumatic or malignant aetiology. Information on vertebral body deformity, pre- and post-procedure sagittal index (SI), wedge angle (WA) and anterior vertebral height ratio was analysed. Two patients had combined ablation and stentoplasty for painful spinal metastases.

RESULTS

There were 11 male and 33 female patients with mean age of 71.5 years (51-90 years). 19 fractured vertebral bodies had more than 30% loss of height. The mean pre-procedure SI was 0.82, and the mean post-procedure SI was 0.90. The pre-procedure WA was -5.56° compared with post-procedure mean WA of -3.47°. The mean pre-procedure segmental kyphosis was -4.58°, and the mean post-procedure segmental kyphosis was -1.46°. Six cases had minimal cement leak, and two cases had a haematoma at the puncture site. None of the patients underwent revision surgery, and postoperative neurological sequelae were not observed.

CONCLUSION

'Central stentoplasty' is a promising percutaneous vertebral fracture augmentation technique, which is shown to have low complication rates in the treatment of spinal compression fractures or metastases. However, long-term results need to be further evaluated.

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.

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.

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

STUDY DESIGN

A case-control study.

OBJECTIVE

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

SUMMARY OF BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSION

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

LEVEL OF EVIDENCE

4.

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.

Clinical outcome after the use of a new craniocaudal expandable implant for vertebral compression fracture treatment: one year results from a prospective multicentric study

The purpose of this prospective multicentric observational study was to confirm the safety and clinical performance of a craniocaudal expandable implant used in combination with high viscosity PMMA bone cement for the treatment of vertebral compression fractures. Thirty-nine VCFs in 32 patients were treated using the SpineJack minimally invasive surgery protocol. Outcome was determined by using the Visual Analogue Scale for measuring pain, the Oswestry Disability Index for scoring functional capacity, and the self-reporting European Quality of Life scores for the quality of life. Safety was evaluated by reporting all adverse events. The occurrence of cement leakages was assessed by either radiographs or CT scan or both. Statistically significant improvements were found regarding pain, function, and quality of life. The global pain score reduction at 1 year was 80.9% compared to the preoperative situation and the result of the Oswestry Disability Index showed a decrease from 65.0% at baseline to 10.5% at 12 months postoperatively. The cement leakage rate was 30.8%. No device- or surgery-related complications were found. This observational study demonstrates promising and persistent results consisting of immediate and sustained pain relief and durable clinical improvement after the procedure and throughout the 1-year follow-up period.

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.

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.