Bone displacement and the role of longitudinal ligaments during balloon vertebroplasty in traumatic thoracolumbar fractures

Effectiveness of unilateral percutaneous vertebroplasty for acute traumatic non-osteoporotic compression vertebral fractures

Although vertebroplasty is a well-known treatment for osteoporotic and neoplastic compression fractures, there is limited evidence to support its use in traumatic compression fractures without osteoporotic degeneration. The purpose of this study was to evaluate the correlation of kyphosis and wedge angles with pain relief and functional outcome after percutaneous vertebroplasty. 38 patients who harbored acute traumatic non-osteoporotic compression vertebral fractures without neurological complications refractory to at least 5 days of conservative treatment were included in this study. Follow-up evaluations included pain (assessed with the visual analog scale) and medication use. Functional outcome was measured using Oswestry low back pain disability questionnaire. Cobb angles, Gardner angles and kyphotic angles were measured on the full-spine radiographs preoperatively and postoperatively. The axial pain visual analog scale score (8.05 ± 1.23 pre-op vs 1.18 ± 1.09 post-op, P < .05) and The Oswestry low back pain disability questionnaire score (33.45 ± 6.97 pre-op vs 4.47 ± 2.41 post-op, P < .05). The Cobb's angle (19.66° ± 8.68° pre-op vs 15.08° ± 7.51° post-op, P < .05), the Gardner's angle (17.72° ± 6.52° pre-op vs 14.13° ± 7.13° post-op, P < .05) and the kyphotic angle (17.51° ± 5.8° pre-op vs 8.81° ± 4.14°post-op, P < .05) were significantly reduced postoperatively therefore, local kyphosis was markedly restored after vertebroplasty. Our findings show that vertebroplasty for patients with traumatic spinal compression fractures reduces pain, improves mobility, reduces the need for painkillers, and significantly affects kyphotic angles.

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.

The mechanism of thoracolumbar burst fracture may be related to the basivertebral foramen

BACKGROUND CONTEXT

The basivertebral foramen (BF), located in the middle posterior wall of the vertebral body, may induce local weakness and contribute to the formation of a retropulsed bone fragment (RBF) in thoracolumbar burst fracture (TLBF). We hypothesize that the mechanism of TLBF is related to the BF.

PURPOSE

This study aimed to clarify the relationship between RBFs and the BF in TLBFs, and to explain the results using biomechanical experiments and micro-computed tomography (micro-CT).

STUDY DESIGN

A comprehensive research involving clinical radiology, micro-CT, and biomechanical experiments on cadaveric spines was carried out.

PATIENT SAMPLE

A total of 162 consecutive patients diagnosed with TLBF with RBFs, drawn from 256 patients who had reported accidents or injuries to their thoracolumbar spine, comprised the patient sample.

OUTCOME MEASURES

Dimensions and location of the RBFs in relation to the BF were the outcome measures.

MATERIALS AND METHODS

Computed tomography reconstruction imaging was used to measure the dimensions and location of RBFs in 162 patients (length, height, width of RBF and vertebral body). Furthermore, micro-CT scans were obtained of 10 cadaveric spines. Each vertebral body was divided into three layers (superior, middle, and inferior), and each layer was divided further into nine regions (R1-R9). Microarchitecture parameters were calculated from micro-CT scans, including bone volume fraction (BV/TV), connectivity (Conn.D), trabecular number (Tb.N), trabecular thickness (Tb.Th), and bone mineral density (BMD). Differences were analyzed between regions and layers. Burst fractures were simulated on cadaveric spines to explore the fracture line location and test the relationship between RBFs and BF.

RESULTS

Retropulsed bone fragment width was usually one-third of the width of the vertebral body, whereas RBF length and height were approximately half of the corresponding vertebral body dimensions. Measures of trabecular bone quality were generally lowest in those central and superior regions of the vertebral body which are adjacent to the BF and which are most affected by burst fracture. In simulated TLBFs, the fracture line went across the vertex or upper surface of the BF.

CONCLUSIONS

The most vulnerable regions in the vertebral body lie within or just superior to the BF. The central MR2 region in particular is at risk of fracture and RBF formation.

Percutaneous stabilization of lumbar spine: a literature review and new options in treating spine pain

Vertebral fracture (VF) is a common condition with >160,000 patients affected every year in North America and most of them with affected lumbar vertebrae. The management of VF is well known and defined by many protocols related to associated clinical neurological symptoms, especially in case of the presence or absence of myelopathy or radicular deficit. In this article, we will explore the percutaneous stabilization of the lumbar spine by showing the newest approaches for this condition.

Percutaneous vertebroplasty: a first line treatment in traumatic non-osteoporotic vertebral compression fractures

STUDY DESIGN

This was a prospective cohort study.

PURPOSE

The purpose of this study was to document and evaluate the clinical and radiological results of percutaneous vertebroplasty (PV) as a first line treatment in traumatic non-osteoporotic vertebral compression fractures (TNVCFs).

OVERVIEW OF LITERATURE

PV is commonly used for osteoporotic and neoplastic compression fractures, however its use in traumatic non-osteoporotic compression fractures is uncertain.

METHODS

We included 23 patients with traumatic non-osteoporotic TNVCFs and normal bone mineral densitometry scores who were treated with PV. Pain was evaluated at 2 hours, 1 week, 1 month, 6 months, 1 year, and 2 years post procedure using the 10-point visual analogue scale (VAS). Ronald-Morris disability Questionnaire (RDQ) scores were also collected. Statistical analysis included a 2-tailed t test comparing postoperative data with preoperative values. Range of mobility was also evaluated.

RESULTS

The 23 patients had an average age of 36 years, and 69.5% were female. There was a significant improvement in VAS scores of pain at rest and in motionand in RDQ scores (p<0.05).

CONCLUSIONS

The results of this study proved that PV can be used successfully as a first line treatment in patients with non-osteoporotic compression fractures. It is also, an effective method to decrease pain, increase mobility, and decrease narcotic administration.

Demineralization after balloon kyphoplasty with calcium phosphate cement: a histological evaluation in ten patients

PURPOSE

Balloon kyphoplasty (BKP) with calcium phosphate cement (CPC) is increasingly being used for spinal surgery in younger patients. In routinely performed follow-up CT scans we observed considerable areas of demineralization in CPC processed vertebrae in several patients. To rule out infections or inflammations histological examinations were planned for these patients.

METHODS

Ten patients (23-54 years; six men) with significant demineralization areas in CT scans after CPC balloon kyphoplasty were selected. Punch biopsies from these areas were taken in local anesthesia using a biopsy needle. One half of the specimen was decalcified and embedded in paraffin, and sections were examined histologically using hematoxylin and eosin, Van Gieson, and trichrome staining. The second half of the specimen was cast directly in methyl methacrylate and sections were examined by Paragon and von Kossa/Safranin staining. Stained slides were viewed under light microscopy.

RESULTS

Bone-punch specimens were taken at 17.5 months (mean) after BKP with CPC. In most cases, the cement was well surrounded by newly formed lamellar bone with very tight connections between the cement and new bone. Unmineralized areas were observed sporadically at the cement surface and adjacent to the implant. There were no pronounced signs of inflammation or osteolysis of adjacent bone. No complications were observed during or following patients' biopsy procedures.

CONCLUSIONS

CPC demonstrated good biocompatibility and osseointegration in clinical use, with no evidence of inflammation or osteonecrosis. Demineralized areas in CT scans could be a result of remodeling of the cancellous bone in vertebral bodies.

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.

Transpedicular vertebral body augmentation reinforced with pedicle screw fixation in fresh traumatic A2 and A3 lumbar fractures: comparison between two devices and two bone cements

This retrospective study compares efficacy and safety of balloon kyphoplasty (BK) with calcium phosphate (Group A) versus KIVA implant with PMMA (Group B) reinforced with three vertebrae pedicle screw constructs for A2 and A3 single fresh non-osteoporotic lumbar (L1-L4) fractures in 38 consecutive age- and diagnosis-matched patient populations. Extracanal leakage of both low-viscosity PMMA and calcium phosphate (CP) as well as the following roentgenographic parameters: segmental kyphosis (SKA), anterior (AVBHr) and posterior (PVBHr) vertebral body height ratio, spinal canal encroachment (SCE) clearance, and functional outcome measures: VAS and SF-36, were recorded and compared between the two groups. All patients in both groups were followed for a minimum 26 (Group A) and 25 (Group B) months. Extracanal CP and PMMA leakage was observed in four (18 %) and three (15 %) vertebrae/patients of group A and B, respectively. Hybrid fixation improved AVBHr, SKA, SCE, but PVBHr only in group B. VAS and SF-36 improved postoperatively in the patients of both groups. Short-segment construct with the novel KIVA implant restored better than BK-fractured lumbar vertebral body, but this had no impact in functional outcome. Since there was no leakage difference between PMMA and calcium phosphate and no short-term adverse related to PMMA use were observed, we advice the use of PMMA in fresh traumatic lumbar fractures.

Safe surgical technique: cement-augmented pedicle screw instrumentation and balloon-guided kyphoplasty for a lumbar burst fracture in a 97-year-old patient

Background

During the last few years, an increasing number of unstable thoracolumbar fractures, especially in elderly patients, has been treated by dorsal instrumentation combined with a balloon kyphoplasty. This combination provides additional stabilization to the anterior spinal column without any need for a second ventral approach.

Case presentation

We report the case of a 97-year-old male patient with a lumbar burst fracture (type A3-1.1 according to the AO Classification) who presented prolonged neurological deficits of the lower limbs - grade C according to the modified Frankel/ASIA score. After a posterior realignment of the fractured vertebra with an internal screw fixation and after an augmentation with non-absorbable cement in combination with a balloon kyphoplasty, the patient regained his mobility without any neurological restrictions.

Conclusion

Especially in older patients, the presented technique of PMMA-augmented pedicle screw instrumentation combined with balloon-assisted kyphoplasty could be an option to address unstable vertebral fractures in “a minor-invasive way”. The standard procedure of a two-step dorsoventral approach could be reduced to a one-step procedure.

A novel method for the reproducible production of thoracolumbar burst fractures in human cadaveric specimens

BACKGROUND CONTEXT

Currently, there is no reproducible method that produces thoracolumbar burst fractures in human cadavers wherein the fracture configuration mirrors that seen naturally, and soft tissues are maintained.

PURPOSE

To describe a novel method of burst fracture production.

STUDY DESIGN

Biomechanical.

METHODS

Five cadaveric specimens were potted in polymethymethacrylate at T10 and L4; T10 to T12 and L2 to L4 were encased in a pourable rigid foam; flexion of 15° was created focused at L1; and a drop tower weight of 25 kg via "free fall" was used. On load delivery, the spine was allowed to flex without restriction (native bony and soft-tissue constraints). X-ray, computed tomography scan, and open dissection were used to confirm burst configuration.

RESULTS

All five specimens were found to have the "classic" burst configuration characterized by superior end plate comminution, depression of the anterior column, middle column burst with three to five fragments; the classic central fragment retropulsed into the canal, and the pedicular spread via basilar fracture.

CONCLUSION

This novel method affords true burst fracture reproduction without "prestressing" (notching, osteotomies, laminectomy, stripping) used in previous methods. This should allow greater accuracy for the translation of biomechanical testing to clinical applications.

Treatment of type-A3 amyelic thoracolumbar fractures (burst fractures) with kyphoplasty: initial experience

The authors propose a minimally invasive procedure for treating type-A3 amyelic thoracolumbar fractures according to Magerl classification (compression burst fractures). The procedure, percutaneous kyphoplasty, allows the fracture to be reduced and vertebral height to be restored by injecting bone cement into a cavity created in the vertebral body by an inflatable balloon introduced with the percutaneous approach. Four patients were successfully treated, with clinical and functional benefit in all cases. There were no complications.

Thoracolumbar burst fractures treated with posterior decompression and pedicle screw instrumentation supplemented with balloon-assisted vertebroplasty and calcium phosphate reconstruction

BACKGROUND

The treatment of unstable thoracolumbar burst fractures with short-segment posterior spinal instrumentation without anterior column reconstruction is associated with a high rate of screw breakage and progressive loss of reduction. The purpose of the present study was to evaluate the functional, neurologic, and radiographic results following transpedicular, balloon-assisted fracture reduction with anterior column reconstruction with use of calcium phosphate bone cement combined with short-segment posterior instrumentation and a laminectomy.

METHODS

A consecutive series of thirty-eight patients with an unstable thoracolumbar burst fracture with or without neurologic deficit were managed with transpedicular, balloon-assisted fracture reduction, calcium phosphate bone cement reconstruction, and short-segment spinal instrumentation from 2002 to 2005. Twenty-eight of the thirty-eight patients were followed for a minimum of two years. Demographic data, neurologic function, segmental kyphosis, the fracture severity score, canal compromise, the Short Form-36 score, the Oswestry Disability Index score, and treatment-related complications were evaluated prospectively.

RESULTS

All thirteen patients with incomplete neurologic deficits had improvement by at least one Frankel grade. The mean kyphotic angulation improved from 17 degrees preoperatively to 7 degrees at the time of the latest follow-up, and the loss of vertebral body height improved from a mean of 42% preoperatively to 14% at the time of the latest follow-up. Screw breakage occurred in two patients, and pseudarthrosis occurred in one patient.

CONCLUSIONS

The present study demonstrates that excellent reduction of unstable thoracolumbar burst fractures with and without associated neurologic deficits can be maintained with use of short-segment instrumentation and a transpedicular balloon-assisted reduction combined with anterior column reconstruction with calcium phosphate bone cement performed through a single posterior incision. The resultant circumferential stabilization combined with a decompressive laminectomy led to maintained or improved neurologic function in all patients with neurologic deficits, with a low rate of instrumentation failure and loss of correction.

Vertebroplasty for the treatment of traumatic nonosteoporotic compression fractures

BACKGROUND AND PURPOSE

Vertebroplasty is commonly used for osteoporotic and neoplastic compression fractures, yet little evidence exists for its use in traumatic nonosteoporotic compression fractures. The purpose of this study was to evaluate the safety and efficacy of percutaneous vertebroplasty for patients with traumatic nonosteoporotic compression fractures.

MATERIALS AND METHODS

We performed a retrospective review of 819 patients (982 procedures) who underwent percutaneous vertebroplasty, to identify patients who had normal bone mineral densitometry scores or had no previous diagnosis of osteoporosis, multiple myeloma, or history of long-term steroid use. Follow-up evaluations included pain at rest and with activity (assessed with the visual analog scale [VAS]), medication use, and mobility. Roland-Morris Disability Questionnaire (RDQ) scores were also collected. Statistical analysis included a 2-tailed t test comparing postprocedure outcomes with baseline values.

RESULTS

Fifteen patients (53% women) were included. Mean age and t-score were 60 years and -0.35, respectively. We found significant improvements in the VAS scores, both at rest and with activity, and in the RDQ scores, starting at the 2-hour follow-up. Additionally, we found marked decreases in medication use and improvements in mobility. The complication rate was low and characterized by asymptomatic extravasation of cement.

CONCLUSIONS

From our study, we have shown that vertebroplasty can be successfully and safely used in patients with traumatic nonosteoporotic compression fractures. Vertebroplasty in these patients should be used after failure of conservative treatments and may be used in place of more invasive spinal reconstruction techniques.

Minimal invasive short posterior instrumentation plus balloon kyphoplasty with calcium phosphate for burst and severe compression lumbar fractures

STUDY DESIGN

Prospective consecutive series.

OBJECTIVE

To evaluate the efficacy of minimal invasive surgery for acute lumbar fractures by means of balloon kyphoplasty with calcium phosphate plus segmental short posterior instrumented fusion.

SUMMARY OF BACKGROUND DATA

In the surgical treatment of lumbar fractures with short pedicle screw instrumentation, the failure to support the anterior spinal column often results in loss of correction. Transpedicular augmentation techniques with bone and bone substitutes have been attempted whereas kyphoplasty has been increasingly used to augment fractured vertebral body.

METHODS

Eighteen consecutive patients with an average age of 64 +/- 15 years, who sustained lumbar (L1-L4) burst and severe compression fracture were included in this prospective study. On admission, 2 (11%) of 18 patients had incomplete neurologic impairment. All patients underwent bilateral balloon kyphoplasty with calcium phosphate bone cement to reduce segmental kyphosis and restore vertebral body height and segmental pedicle screw instrumentation and fusion. Gardner kyphosis angle, anterior (AVBHr) and posterior vertebral body height ratio (PVBHr), and spinal canal encroachment (SCE) were calculated before to after surgery. VAS and SF-36 were used to evaluate functional outcome.

RESULTS

All patients were operated within 24 hours after admission and were followed for an average 22 months (17-28 months) after index surgery. Operating time and blood loss averaged 45 minutes and 70 mL, respectively. VAS and SF-36 (role physical and bodily pain domains) were significantly improved after surgery. Both patients with incomplete neurologic lesions recovered, whereas no neurologic deterioration was observed in any case. Segmental kyphosis improved from an average preoperative kyphosis of 16 to 2 degrees after surgery (P < 0.000). AVBHr improved from an average before surgery 0.57 to 0.87 (P < 0.000) after surgery, whereas PVBHr improved from 0.93 before surgery to 0.98 (P < 0.05) after surgery. SCE was reduced from an average 25% before surgery to 19% (P < 0.07) after surgery. Bone cement leakage was observed anteriorly to the fractured vertebral body or to the adjacent superior disc in 4 patients without clinical sequelae, whereas 3 pedicle screws were malpositioned medially to the pedicle in 3 patients without neurologic impairment or associated complaints. Posterolateral radiologic fusion was achieved within 6 to 8 months after index operation. There was no instrumentation failure or loss of sagittal curve and vertebral height correction.

CONCLUSION

Balloon kyphoplasty with calcium phosphate cement combined with posterior segmental short minimal invasive fixation for fresh burst and severe compression lumbar fractures provided excellent immediate reduction of post-traumatic segmental kyphosis with simultaneous reduction of spinal canal encroachment and restoration of vertebral body height in the fracture level.

Vertebroplasty and Kyphoplasty

Percutaneous vertebroplasty and kyphoplasty provide minimally invasive options for the management of osteoporotic and osteolytic vertebral compression fractures. These techniques provide substantial pain relief and support without requiring long periods of recumbency, and have an acceptable complication rate. Vertebral augmentation techniques such as vertebroplasty and kyphoplasty provide pain relief and improvement in quality of life in the highly selected patient. Complications can be avoided with careful surgical technique, and good outcomes can be achieved with proper patient selection.

The role of 3-D rotational x-ray imaging in spinal trauma

The most widely used imaging devices in trauma spine surgery are fluoroscopy and computed tomography. Both techniques have their specific pros and cons and expose both patient and operating staff to considerable radiation during image acquisition. Three-dimensional-rotational x-ray imaging (3-DRX) is a relatively new technique in which a C-arm is moved around the patient to allow for an "acquisition run" during which multiple fluoroscopy images are obtained. The images can subsequently be processed on a workstation into a 3-D volume, which can then be manipulated in a similar way to 3-D computed tomography data. The 3-DRX technique combines the advantages of both fluoroscopy and computed tomography: fast visual feedback and high resolution multiplanar reformatted images, respectively, and could be used in an intraoperative setting. In this paper some technical aspects of 3-DRX imaging and its potential role in spinal trauma treatment are presented.

Less invasive anterior column reconstruction in thoracolumbar fractures

Posterior short-segment pedicle screw constructs are commonly used for reduction and fixation of traumatic thoracolumbar spine fractures. Although this technique is usually simple and effective, complications such as loss of fixation or recurrence of deformity are common because of the insufficiency of the damaged anterior column. Anterior approaches to address this deficiency are associated with high morbidity and complications. We have developed a technique to reduce and support the fractured anterior column through a transpedicular approach. Balloon-assisted-endplate-reduction (BAER) followed by vertebroplasty (VTP) with calcium phosphate cement in combination with short segment pedicle screw construct seem to be a safe and effective technique to reconstruct the anterior column in a less invasive manner. In this article, the rationale behind this technique, experimental studies, and the first clinical results are discussed.