Kyphoplasty for vertebral compression fractures: 1-year clinical outcomes from a prospective study

Vertebral body collapse after spine stereotactic body radiation therapy: a single-center institutional experience

BACKGROUND

Spine stereotactic body radiation therapy (SBRT) for the treatment of metastatic disease is increasingly utilized owing to improved pain and local control over conventional regimens. Vertebral body collapse (VBC) is an important toxicity following spine SBRT. We investigated our institutional experience with spine SBRT as it relates to VBC and spinal instability neoplastic score (SINS).

PATIENTS AND METHODS

Records of 83 patients with 100 spinal lesions treated with SBRT between 2007 and 2022 were reviewed. Clinical information was abstracted from the medical record. The primary endpoint was post-treatment VBC. Logistic univariate analysis was performed to identify clinical factors associated with VBC.

RESULTS

Median dose and number of fractions used was 24 Gy and 3 fractions, respectively. There were 10 spine segments that developed VBC (10%) after spine SBRT. Median time to VBC was 2.4 months. Of the 11 spine segments that underwent kyphoplasty prior to SBRT, none developed subsequent VBC. No factors were associated with VBC on univariate analysis.

CONCLUSIONS

The rate of vertebral body collapse following spine SBRT is low. Prophylactic kyphoplasty may provide protection against VBC and should be considered for patients at high risk for fracture.

Double-Balloon Kyphoplasty Results in Better Radiographic Outcomes Than a Single-Balloon Kyphoplasty in Treating Osteo-Porotic Spinal Fractures

Background: Studies have found that unilateral and bilateral kyphoplasty have comparable clinical outcomes. Only a few studies have compared the radiographic results of using unilateral vs. simultaneous bilateral approaches. We aimed to examine and compare the radiographic results of unilateral (UKP) vs. bilateral simultaneous double-balloon kyphoplasty (DKP) for treating symptomatic vertebral compression fractures (VCF). Methods: A retrospective cohort of all patients treated for VCF by DKP and UKP over five years in a single medical center. From 2009 to 2012, we routinely performed UKP; from 2012, DKP was the routine due to potential benefits in vertebral realignment. We evaluated pre- and post-surgical fracture characteristics including vertebral height, sagittal and coronal Cobb angle, and fracture reduction. Statistical analysis included a t-test for independent variables and Pearson’s correlation. Results: The study cohort consisted of 81 patients (75.8 years ± 10.86) who underwent surgery, with a total of 119 vertebras. We performed 89 UKP on fractured vertebras and 30 DKP on 30 vertebrae. The UKP average fluoroscopy radiation exposure was 15.8 mGy (±11.5) per level compared to 11.2 mGy (±8.7) for DKP, p = 0.03. DKP showed significant fracture reduction, 2.8 degrees of Cobb angle, equaling the patient positioning effect on fracture reduction. Conclusion: DKP results in better fracture reduction than UKP, and equals the effect of patient positioning without increased radiation exposure or adverse events.

Percutaneous Kyphoplasty for Osteoporotic Vertebral Compression Fractures Associated with Spinal Canal Encroachment without Neurological Symptoms

Background

Percutaneous kyphoplasty (PKP) has been widely used for osteoporotic vertebral compression fractures (OVCFs). However, whether this approach is suitable for osteoporotic vertebral fractures with spinal canal encroachment remains controversial.

Material/Methods

Of 526 patients who underwent PKP at our hospital, 40 had conditions associated with spinal canal encroachment, and were enrolled in the study. Detailed physical, neurological, and radiological examinations were performed on each patient before and after surgery and at the followup. A visual analog scale (VAS) and the Oswestry Disability Index (ODI) were used for the clinical assessment. The vertebral body height, the local kyphosis, and the spinal canal width were used for the radiological evaluation.

Results

There were 11 male and 29 female patients, with a mean age of 71±8 years. The VAS score decreased from 6.4±0.7 preoperatively to 1.6±0.7 postoperatively and to 2.3±1.5 at the last followup visit. The ODI score was 78±9.5 before surgery, declined to 24±11.3 after surgery, and was 27.6±12.5 at the last followup visit. The vertebral body height increased from 11.7±4.3 mm to 14.6±4.4 mm. The local kyphosis decreased from 15.0±10.7 degrees preoperatively to 8.5±11.3 degrees postoperatively. The spinal canal width remained stable, at 8.5±2.0 mm before PKP and 8.7±1.9 after PKP.

Conclusions

PKP effectively relieved back pain in OVCF patients with spinal canal encroachment. Their social function improved as well.

Modeling of kyphoplasty cement for accurate dose calculations

We have determined the optimal method for modeling kyphoplasty cement to enable accurate dose calculations in the Eclipse treatment planning system (TPS). The cement studied (Medtronic Kyphon HV‐R®) consists of 30% Barium, 68% polymethylmethacrylate (PMMA), and 2% benzoyl peroxide, formulated to be radiopaque with kV imaging systems. Neither Barium nor PMMA have a high physical density, resulting in different interaction characteristics for megavoltage treatment beams compared to kV imaging systems. This can lead to significant calculation errors if density mapping is performed using a standard CT number to density curve. To properly characterize the cement for dose calculation, we 3D printed a hemi‐cylindrical container to fit adjacent to a micro‐chamber insert for an anthropomorphic phantom, and filled the container with Kyphon cement. We CT scanned the combination, modeled the cement with multiple material assignments in the TPS, designed plans with different field sizes and beam geometry for five photon modes, and measured the doses for all plans. All photon energies show significant error in calculated dose when the cement is modeled based on the CT number. Of the material assignments we evaluated, polytetrafluoroethylene (PTFE) showed the best overall agreement with measurement. Calculated and measured doses agree within 3.5% for a 340‐degree arc technique (which averages transmission and scatter effects) with the Acuros XB algorithm and PTFE as the assigned material. To confirm that PTFE is a reasonable substitute for kyphoplasty cement, we performed measurements in a slab phantom using rectangular inserts of cement and PTFE, showing average agreement of all photon modes within 2%. Based on these findings, we conclude that the PTFE material assignment provides acceptable dose calculation accuracy for the AAA and Acuros XB photon algorithms in the Eclipse TPS. We recommend that the cement be delineated as a structure and assigned the PTFE material for accurate dose calculation.

Distribution of Prevalent and Incident Vertebral Fractures and Their Association with Bone Mineral Density in Postmenopausal Women in the Teriparatide Versus Risedronate VERO Clinical Trial

Vertebral fractures (VFx) occur most frequently in the mid-thoracic and thoraco-lumbar regions, which experience the highest mechanical loading along the spine. The prevalence and incidence of VFx by their location and severity, and their relationship with bone mineral density (BMD), are seldom reported in randomized clinical trial cohorts. The VERO trial randomized 1360 postmenopausal women with at least two moderate or one severe VFx to receive either teriparatide or risedronate for up to 24 months. In this post hoc analysis, we describe the centrally read distribution and severity of prevalent and incident VFx, and the association of their location with the baseline BMD. At baseline, 21.4% of all evaluable vertebral bodies had a prevalent VFx; most commonly at L₁, T₁₂, L₂ and T₁₁ (38.5%, 37.4%, 25.3% and 23.5% of patients, respectively). Patients with prevalent VFx only at T₁₂/L₁ showed a higher baseline BMD compared to patients with VFx at other levels. At month 24, 100 patients had 126 incident VFx (teriparatide: 35; risedronate: 91). The most frequent incident VFx occurred at T₁₂ (n = 17, 1.6% of patients), followed by L₁ and T₁₁ (n = 14, 1.3% both). The frequency of incident VFx was lower at all vertebral levels in patients given teriparatide. These results confirm prior reports that VFx occurs more frequently at mid-thoracic and thoraco-lumbar regions of the spine. Patients with these VFx locations have higher BMD than those who fracture at other sites, suggesting a role for mechanical stress in the etiology of VFx. Teriparatide is superior to risedronate in the prevention of VFx at these common fracture locations.Trial registration ClinicalTrials.gov Identifier: NCT01709110.

Extrapendicular Approach of Unilateral Percutaneous Vesselplasty for the Treatment of Kummell Disease

Background

Our purpose was to evaluate the efficacy of the extrapendicular approach for unilateral percutaneous vesselplasty in dealing with Kummell disease patients.

Methods

Twenty-seven patients undergoing vesselplasty at our institution were enrolled in the study. Vesselplasty was performed using percutaneous extrapendicular technique. Pain, restoration of vertebral body height, and cement leakage were evaluated in the process.

Results

Substantial pain relief was attained in all the patients. The visual analogue scale improved significantly from pre- to postoperation (P < .05), and remained unchanged at every follow-up. The anterior vertebral body heights were significantly corrected after operation (P < .05). No cement leakage was found.

Conclusion

This new technique of vesselplasty offers statistically significant benefits in Kummell disease patients. It also makes vesselplasty feasible, safe, and effective.

Percutaneous Vertebral Augmentation Techniques in Osteoporotic and Traumatic Fractures

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

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.

Percutaneous Endoscopic Retrieval of Intraspinal Cement Leakage: Technical Note

OBJECTIVE

We sought to preliminarily explore the efficacy and safety of percutaneous endoscopic spinal surgery for epidural cement leakage. We report a case series of patients who underwent percutaneous retrieval of leaked epidural cement and achieved spinal decompression under endoscopy.

METHODS

Five patients with neurologic impairment due to epidural cement leakage after percutaneous vertebroplasty were treated with percutaneous endoscopic spinal decompression. Computed tomography reconstruction and 3-dimensional imaging were used to evaluate the extruded material. During follow-up at 3, 6, and 12 months postoperatively, all patients were advised to undergo plain radiograph and computed tomography examinations.

RESULTS

The leaked epidural cement was successfully removed in all patients under percutaneous endoscopy through a unilateral or bilateral approach. At the 12-month follow-up, the visual analog scale score of all patients improved. In addition, the neurologic function of each patient improved to at least 1 grade level, as evaluated using the American Spinal Injury Association. According to the modified MacNab criteria, 2 patients had excellent recovery, whereas the other 3 patients had good recovery.

CONCLUSIONS

We described a novel and minimally invasive procedure to ameliorate intractable epidural cement extrusion. As an alternative to conventional laminectomy, percutaneous endoscopic retrieval achieved the targeted decompression without damaging the posterior lamina. Moreover, the whole operation was performed under regional anesthesia accompanied with dexmedetomidine sedation, allowed real-time neural function evaluation, and had lower risks of anesthesia-related complications, compared with general anesthesia.

Is additional balloon Kyphoplasty safe and effective for acute thoracolumbar burst fracture?

BACKGROUND

Burst fracture is a common thoracolumbar injury that is treated using posterior pedicle instrumentation and fusion combined with transpedicular intracorporeal grafting after reduction. In this study, we compared the outcome of these two techniques by using radiologic imaging and functional outcome.

METHODS

Sixty-one patients with acute thoracolumbar burst fracture were operated with kyphoplasty (n = 31) or vertebroplasty (n = 30) and retrospectively reviewed in our institution between 2011 and 2014. All 61 patients underwent surgery within 5 days after admission to the hospital and then followed-up for 12 to 24 months after surgery.

RESULTS

Significant improvement was found in the anterior vertebral height (92 ± 8.9% in the kyphoplasty group, 85.6 ± 7.2% in the vertebroplasty group, p < 0.01) at 1 month post-operatively and (89 ± 7.9% in the kyphoplasty group, 78 ± 6.9% in the vertebroplasty group, p < 0.01) at the 24-month follow-up. Significant improvement was also observed in the kyphotic angle (1.2 ± 0.5° in the kyphoplasty group, 10.5 ± 1.2° in the vertebroplasty group, p < 0.01) at 1 month post-operatively and (5.4 ± 1.2° in the kyphoplasty group, 11.5 ± 8.5° in the vertebroplasty group, p < 0.01) at the 24-month follow-up. Both operations led to significant improvement of the patients' pain and the Oswestry disability index (p < 0.01). Cement leakage was noted in 29% of patients after kyphoplasty and 77% of patients after vertebroplasty (p < 0.01). Only one implant failure (3.3%), which required further surgical intervention, was reported in the vertebroplasty group.

CONCLUSIONS

Reduction with additional balloon at the fractured site is better than indirect reduction only by posterior instrumentation. The better reduction of kyphotic angle and the lower cement leakage rate in the kyphoplasty group indicate that additional balloon kyphoplasty is safe and effective for acute thoracolumbar burst fracture.

Outcome of balloon kyphoplasty for the treatment of osteoporotic vertebral compression fracture in patients with rheumatoid arthritis

BACKGROUND

Osteoporosis and osteoporotic fractures are widely known as complications of rheumatoid arthritis. Kyphoplasty (KP) is known as an effective treatment modality for reducing pain and correcting kyphotic deformity in osteoporotic vertebral compression fracture (OVCF). However, cutcomes of KP in rheumatoid patients are not well known. The purpose of the study was to investigate the clinical and radiological outcomes of balloon KP on OVCF in patients with rheumatoid arthritis.

METHODS

A total of 23 patients (31 vertebral bodies) with rheumatoid arthritis who received KP for OVCF and could be followed up for at least 1 year were examined. For clinical outcomes, visual analogue scale (VAS) and the Korean version of the Oswestry disability index (KODI) were evaluated. For radiological outcomes, changes in anterior vertebral height and local kyphotic angle were measured, alongside cement leakage, adjacent fracture, and the recollapse of cemented vertebra.

RESULTS

The anterior vertebral height was significantly restored after surgery compared with prior to surgery (p < 0.001). Cement leakage was found in 14 cases (45.1 %), and disc space leakage was prevalent (50 %), while vascular cement leakage was found in one case. Adjacent fracture was found in 3 patients (11.5 %). VAS for lumbago showed a significant decrease (p < 0.001) after surgery (VAS = 2.4) compared with that before (VAS = 8.1); it was somewhat increased after the 1-year follow-up (VAS = 2.8; p = 0.223). KODI also decreased (48.8 %) after surgery compared with before (84.6 %). However, it increased somewhat (49.9 %) after the 1-year follow-up.

CONCLUSION

KP on rheumatoid arthritis patients for OVCF was effective for reducing pain in the early stage and restoring vertebral body height. Recollapse of the treated vertebral body was found relatively frequently alongside the correction loss of local kyphotic angle.

Role of stereotactic body radiotherapy in spinal metastasis and subsequent fracture risk: identifying and treating the at-risk patient

The treatment of spinal metastasis has considerably improved with the advent of stereotactic body radiotherapy. Technological advances have enabled the precise delivery of high-dose radiation that may supplant surgery and standard fractionation postoperative radiation as a treatment for spinal metastasis without cord compression. Unfortunately, the higher biologically equivalent doses conferred by stereotactic body radiotherapy can also result in radiation toxicity, notably myelitis and vertebral body fracture. These are toxicities that the radiation oncologist must be able to anticipate, mitigate and manage. Although myelitis can be prevented largely by instituting dose constraints, it is less clear what the fracture risk of a structurally compromised vertebra is, and what should be done in terms of stabilization and dosimetry to mitigate this risk. This review answers these questions by defining the appropriate patient for stereotactic body radiotherapy, and what dose, fractionation and spinal stabilization should be used for potentially unstable spines.

Outcome of percutaneous balloon kyphoplasty in vertebral compression fractures

BACKGROUND

Incidence of vertebral compression fractures (VCFs) is increasing due to increase in human life expectancy and prevalence of osteoporosis. Vertebroplasty had been traditional treatment for pain, but it neither attempts to restore vertebral body height nor eliminates spinal deformity and is associated with a high rate of cement leakage. Balloon kyphoplasty involves introduction of inflatable balloon into the fractured body of vertebra for elevation of the end-plates prior to fixation of the fracture with bone cement. This study evaluates short term functional and radiological outcomes of balloon kyphoplasty. The secondary aim is to explore short-term complications of the procedure.

MATERIALS AND METHODS

A retrospective study of 199 kyphoplasty procedures in 135 patients from March 2009 to March 2012 were evaluated with short form-36 (SF-36) score, visual analogue scale (VAS), detailed neurological and radiological evaluations. The mean followup was 18 months (range 12-20 months). Statistical analysis including paired sample t-test was done with statistical package for social sciences.

RESULTS

Statistically significant improvements in SF-36 (from 34.29 to 48.53, an improvement of 14.24, standard deviation (SD) - 20.08 P < 0.0001), VAS (drop of 4.49, from 6.74 to 2.24, SD - 1.44, P < 0.0001), percentage restoration of lost vertebral height (from 30.62% to 16.19%, improvement of 14.43%, SD - 15.37, P < 0.0001) and kyphotic angle correction (from 17.41° to 10.59°, improvement of 6.82, SD - 7.26°, P < 0.0001) were noted postoperatively. Six patients had cement embolism, 65 had cement leak and three had adjacent level fracture which required repeat kyphoplasty later. One patient with history of ischemic heart disease had cardiac arrest during the procedure. No patients had neurological deterioration in the followup period.

CONCLUSIONS

Kyphoplasty is a safe and effective treatment for VCFs. It improves physical function, reduces pain and corrects kyphotic deformity.

Percutaneous cement augmentation techniques for osteoporotic spinal fractures

Minimally invasive vertebral augmentation-based techniques have been used for the treatment of spinal fractures (osteoporotic and malignant) for approximately 25 years. In this review, we try to give an overview of the current spectrum of percutaneous augmentation techniques, safety aspects and indications. Crucial factors for success are careful patient selection, proper technique and choice of the ideal cement augmentation option. Most compression fractures present a favourable natural course, with reduction of pain and regainment of mobility after a few days to several weeks, whereas other patients experience a progressive collapse and persisting pain. In this situation, percutaneous cement augmentation is an effective treatment option with regards to pain and disability reduction, improvement of quality of life and ambulatory and pulmonary function.

Percutaneous vertebroplasty for Langerhans cell histiocytosis of the lumbar spine in an adult: Case report and review of the literature

Langerhans cell histiocytosis (LCH) is extremely rare in the lumbar spine of adults. The radiological features typically manifest as vertebral tumors. The exact etiology of LCH remains unknown. Langerhans cells may cause local or systemic effects. The most frequent sites of these bony lesions are the skull, femur, mandible, pelvis and spine. To date, only 3 spinal LCH cases treated by percutaneous vertebroplasty (PVP) have been reported. The present study reports a case of LCH of the fourth lumbar vertebra (L4) in a 51-year-old male with a 10-day history of low back pain, limited waist motion and right lower limb numbness. The patient was treated using PVP. The use of PVP for treating LCH of the spine was successful. The present study provides an up-to-date literature overview of LCH.

Comparative clinical results of vertebroplasty using jamshidi® needle and bone void filler for acute vertebral compression fractures

OBJECTIVE

Percutaneous vertebroplasty (PVP) is an effective treatment modality for management of osteoporotic compression fracture. However physicians sometimes have problems of high pressure in cement delivery and cement leakage when using Jamshidi® needle (JN). Bone void filler (BVF) has larger lumen which may possibly diminish these problems. This study aims to compare the radiologic and clinical outcome of JN and BVF for PVP.

METHODS

One hundred twenty-eight patients were treated with PVP for osteoporotic vertebral compression fracture (VCF) where 46 patients underwent PVP with JN needle and 82 patients with BVF. Radiologic outcome such as kyphotic angle and vertebral body height (VBH) and clinical outcome such as visual analog scale (VAS) scores were measured after treatment in both groups.

RESULTS

In JN PVP group, mean of 3.26 cc of polymethylmethacrylate (PMMA) were injected and 4.07 cc in BVF PVP group (p<0.001). For radiologic outcome, no significant difference in kyphotic angle reduction was observed between two groups. Cement leakage developed in 6 patients using JN PVP group and 2 patients using BVF group (p=0.025). No significant difference in improvement of VAS score was observed between JN and BVF PVP groups (p=0.43).

CONCLUSION

For the treatment of osteoporotic VCF, usage of BVF for PVP may increase injected volume of cement, easily control the depth and direction of PMMA which may reduce cement leakage. However, improvement of VAS score did not show difference between two groups. Usage of BVF for PVP may be an alternative to JN PVP in selected cases.

Respiratory effects, hemodynamic changes and cement leakage during multilevel cement balloon kyphoplasty

PURPOSE

The purpose of this study is to evaluate the effects of multilevel balloon kyphoplasty (BK) on blood pressure, blood gases and cement leakage.

METHODS

This is a prospective study of 63 patients: 31 were treated for osteoporotic vertebral compressive fractures (OVCF) and 32 for osteolytic tumors (OT). Twenty-six patients were treated at 1 level, 15 at 2, 2 at 3, 6 at 4, 3 at 5, 4 at 6, 5 at 7 and 2 at 8. PPMA was used in 43 patients and calcium phosphate in 20. All patients were treated under general anesthesia with continuous invasive monitoring of hemodynamic changes, arterial blood gases and peripheral and regional cerebral oxygen saturation.

RESULTS

Two patients had a transient drop in blood pressure between 21 and 42 % during simultaneous inflation of all four balloons at two levels and three more patients during cement injection (two PMMA, one calcium phosphate). Five patients had a cement leak (7.9 %), which was unrelated to the cement type or number of levels. Blood pressure, end-tidal carbon dioxide partial pressure and arterial oxygen partial pressure decreased statistically, but without any clinical significance after cement insertion. Peripheral and regional cerebral oxygen saturation remained unchanged. One-way ANOVA revealed no difference between these changes when clustered by the groups single level, two levels and three or more levels.

CONCLUSION

BK performed under general anesthesia appears to be safe when applied in multiple levels in the same seating provided the balloons are inflated sequentially and not simultaneously and the cement is inserted slowly in a very doughy state. Close monitoring of cardiorespiratory factors is valuable. Its rare circulatory effects are unrelated to the number of levels or the cement type.

Filler Materials Used in Kyphoplasty and Vertebroplasty for Osteoporotic Vertebral Compression Fractures

Osteoporosis is the most common metabolic bone disease and the most common cause of fractures in older adults. Vertebral compression fracture (VCF) is the most common complication in patients with osteoporosis. At present, vertebroplasty (VP) and kyphoplasty (KP) are two minimally invasive techniques used to treat osteoporotic vertebral compression fractures. In clinical use, KP and VP have stable and reliable therapeutic effects. However, there are still some complications and issues surrounding KP and VP application, and for long-term clinical follow-up. Thus, it is important to continue to improve the technology of the filler materials used in KP and VP in order to evolve the biomechanical characteristics of the postoperative vertebra, and to reduce the incidence of complications. The filler materials used for both techniques require good biocompatibility, good biomechanical strength and stiffness, and good radiopacity for the fluoroscopy guided procedures. PMMA and new filler materials (calcium phosphate cement, calcium sulfate cement, composite materials) are now available for clinical use. In this review paper, we will focus on the issues and characteristics of these filler materials.

Vertebroplasty and kyphoplasty for the palliation of pain

Vertebroplasty and kyphoplasty are percutaneous techniques developed over the past 20 years to treat vertebral hemangiomas, osteoporotic compression fractures, and osteolytic tumors of the spine. In carefully selected patients, these procedures have led to the cessation or significant reduction in pain in 80 to 90% of patients. In this article, we review the indications and contraindications of these procedures, appropriate patient selection and evaluation, the technique, outcomes, and the potential complications of this form of therapy when performed for the alleviation of pain for osteolytic tumors of the spine.

Measuring spine fracture outcomes: common scales and checklists

INTRODUCTION

Although outcome instruments have been used extensively in spine surgical research, few studies at present specifically address their use in investigations regarding spine trauma. In this review we provide a summary of the outcome instruments used most frequently in spine trauma research, identify the unique challenges of studying outcomes of spine trauma patients, and propose an integrated approach that may be beneficial for future studies.

METHODS

We reviewed the use of outcome instruments applicable to spine trauma research, including generic health measures, inventories of back-specific function, pain scales, health related quality of life (HRQOL) instruments, and radiographic determinants of outcome.

RESULTS

Several inventories have been utilised to measure clinical outcomes following spinal trauma. Excluding measures of neurological function (e.g. ASIA motor score), none have been specifically validated for use with spine fractures. The SF-36, RMDQ, and ODI are amongst the most commonly used instruments. Importantly, the use of validated functional outcome measures in spine trauma research is hampered by the fact that the pre-morbid state of patients who sustain spine trauma may not be accurately represented by normative values established for the general population. The VAS is used most frequently to assess degree of neck and back pain. Most studies have relied on non-validated measures to determine radiographic results of treatment, although more elegant radiographic metrics exist.

CONCLUSIONS

Functional outcome measurement of traumatically injured spine patients is challenging because available generic and spine-specific instruments were not designed for or validated in this population. Furthermore, no single inventory is capable of capturing global data necessary to evaluate results following these injuries. Investigations seeking to quantify outcomes following spine trauma should consider the use of a combination of existing surveys in a complementary fashion that should include a generic health survey, a measure of back-specific function, and determinants of bodily pain and work-related disability.

Prediction of immediate and long-term benefit after kyphoplasty of painful osteoporotic vertebral fractures by preoperative MRI

BACKGROUND

It is unclear if an MR-detectable bone marrow edema is a prerequisite for pain reduction and morphological correction by kyphoplasty. This comparative trial evaluates clinical and radiomorphological outcomes after kyphoplasty of painful osteoporotic vertebral fractures with and without preoperative MR-detectable bone marrow edema for 1 year of follow-up.

METHODS

Preoperative MR-images of 45 patients who received kyphoplasty for treatment of painful osteoporotic vertebral fractures were evaluated with regard to presence (n = 27) or absence (n = 18) of vertebral bone marrow edema. Pain scores (VAS 0-100) and radiomorphological measures (midline vertebral height, kyphosis angle) were analysed at baseline, postoperatively and after 12 months.

RESULTS

In the "bone edema" group, pain scores improved from 72.7 to 46.8 (postoperative) and 48.0 (12 months, P < 0.001, both). In the group without preoperative bone edema, pain score improved from 70.7 to 60.3 (postoperative, P = 0.013) and to 50.1 (12 months, P = 0.001). Pain scores of both groups were significantly different directly postoperative (P = 0.026), but not after 12 months (P = 0.714). Vertebral height restoration was slightly greater in the "bone edema" group (10.2% vs. 7.8%, P = 0.289). Correction of the kyphosis angle was greater in the "bone edema" group (P = 0.014) compared to the "no bone edema" group (P = 0.838).

CONCLUSION

A preoperative MR-detectable vertebral bone marrow edema predicts a better short-term outcome after kyphoplasty, but is not a prerequisite for long-term pain reduction in patients with old, chronically painful osteoporotic vertebral fractures.

Epidural cement leakage through pedicle violation after balloon kyphoplasty causing paraparesis in osteoporotic vertebral compression fractures - a report of two cases

Kyphoplasty is advantageous over vertebroplasty in terms of better kyphosis correction and diminished risk of cement extravasations. Literature described cement leakage causing neurological injury mainly after vertebroplasty procedure; only a few case reports show cement leakage with kyphoplasty without neurological injury or proper cause of leakage. We present a report two cases of osteoporotic vertebral compression fracture treated with kyphoplasty and developed cement leakage causing significant neurological injury. In both cases CT scan was the diagnostic tool to identify cause of cement leakage. CT scan exhibited violation of medial pedicle wall causing cement leakage in the spinal canal. Both patients displayed clinical improvement after decompression surgery with or without instrumentation. Retrospectively looking at stored fluoroscopic images, we found that improper position of trocar in AP and lateral view simultaneously while taking entry caused pedicle wall violation. We suggest not to cross medial pedicle wall in AP image throughout the entire procedure and keeping the trocar in the center of pedicle in lateral image would be the most important precaution to prevent such complication. Our case reports adds the neurological complications with kyphoplasty procedure and suggested that along with other precautions described in the literature, entry with trocar along the entire procedure keeping the oval shape of pedicle in mind (under C-arm) will probably help to prevent such complications.

Efficacy of percutaneous vertebral augmentation and use of physical therapy intervention following vertebral compression fractures in older adults: a systematic review

PURPOSE

The purpose of this systematic literature review was to summarize information on the efficacy of percutaneous vertebral augmentation (PVA) and the incorporation of physical therapy intervention following PVA for vertebral compression fractures (VCF).

METHODS

Literature searches were completed using the Cochrane Library: Cochrane Database of Systematic Reviews (Cochrane Reviews); Agency for Healthcare Research and Quality (AHRQ): National Guideline Clearinghouse; Physiotherapy Evidence Database (PEDro); Medline; and Cumulative Index of Nursing and Allied Health Literature (CINAHL) through August 2005.

RESULTS

Seventeen relevant studies were identified. They reported favorable outcomes (eg, earlier mobility, decreased pain, and improved spinal posture) after PVA. No study addressed physical therapy intervention after PVA.

CONCLUSION

PVA appears to be an effective treatment option for individuals with VCF. However, research dealing with physical therapy after PVA is needed.

Balloon-related complications and technical failures in kyphoplasty for vertebral fractures

BACKGROUND AND PURPOSE

Our aim was to describe the immediate or early complications and technical failures occurring during balloon kyphoplasty (BKP) procedures and attributable to balloon inflation.

MATERIALS AND METHODS

We performed a retrospective review of all consecutive kyphoplasty procedures performed in our institution from May 2005 to October 2006. Fifty-one patients were treated by BKP at 75 spinal levels, and 137 vertebroplasties were performed as well.

RESULTS

Several recurrent complications or procedural failures were observed during BKP: cortical or endplate fracture by balloon expansion (4 vertebrae), partial vertebral re-collapse after deflation (4 vertebrae), balloon rupture during inflation (5 vertebrae), and transient hyperalgia after the procedure (11 patients, 27.5%).

CONCLUSIONS

Several symptomatic or asymptomatic complications and technical failures can occur during BKP. Some modifications of the usual kyphoplasty technique may decrease the frequency of these complications.

Vesselplasty: a new technical approach to treat symptomatic vertebral compression fractures

OBJECTIVE

The objective of our study was to evaluate the effectiveness and safety of vesselplasty to treat symptomatic vertebral compression fractures (VCFs).

SUBJECTS AND METHODS

Twenty-nine patients undergoing vesselplasty at our institution between April 2006 and February 2008 were enrolled in the study. All patients had been undergoing medical therapy for one or more painful VCFs. Pain, mobility, and analgesic use scores were obtained, and restoration of vertebral body height was evaluated. A two-tailed paired Student's t test was used to compare differences in the mean scores for levels of pain, mobility, and analgesic use before and after the procedure and to evaluate changes in vertebral body height. We analyzed the influence of the age of the fracture and its cause in the variations in the pain, mobility, and analgesic use scores.

RESULTS

Seven of the 29 patients had fractures in more than one level, for a total of 37 procedures. The cause of the vertebral collapse was osteoporosis in 27 (73%), high-impact trauma in five (13.5%), myeloma in three (8%), and metastatic fracture in two (5.4%). The average pain score before treatment was 8.72 +/- 1.25 (SD), whereas the average pain score after treatment was 3.38 +/- 2.35. The average mobility score before treatment was 2.31 +/- 1.94, whereas the average mobility score after treatment was 0.59 +/- 1.05 (p < 0.001). The average analgesic use score before treatment was 3.07 +/- 1.46, whereas it was 1.86 +/- 1.90 after treatment (p < 0.001). There was no evidence of clinical complications.

CONCLUSION

Vesselplasty offers statistically significant benefits in improvements of pain, mobility, and the need for analgesia in patients with symptomatic VCFs, thus providing a safe alternative in the treatment of these fractures.

Differences in endplate deformation of the adjacent and augmented vertebra following cement augmentation

Vertebral cement augmentation can restore the stiffness and strength of a fractured vertebra and relieve chronic pain. Previous finite element analysis, biomechanical tests and clinical studies have indirectly associated new adjacent vertebral fractures following augmentation to altered loading. The aim of this repeated measures in situ biomechanical study was to determine the changes in the adjacent and augmented endplate deformation following cement augmentation of human cadaveric functional spine units (FSU) using micro-computed tomography (micro-CT). The surrounding soft tissue and posterior elements of 22 cadaveric human FSU were removed. FSU were assigned to two groups, control (n = 8) (loaded on day 1 and day 2) and augmented (n = 14) (loaded on day 1, augmented 20% cement fill, and loaded on day 2). The augmented group was further subdivided into a prophylactic augmentation group (n = 9), and vertebrae which spontaneously fractured during loading on day 1 (n = 5). The FSU were axially loaded (200, 1,000, 1,500-2,000 N) within a custom made radiolucent, saline filled loading device. At each loading step, FSUs were scanned using the micro-CT. Endplate heights were determined using custom software. No significant increase in endplate deformation following cement augmentation was noted for the adjacent endplate (P > 0.05). The deformation of the augmented endplate was significantly reduced following cement augmentation for both the prophylactic and fracture group (P < 0.05, P < 0.01, respectively). Endplate deformation of the controls showed no statistically significant differences between loading on day 1 and day 2. A linear relationship was noted between the applied compressive load and endplate deflection (R (2) = 0.58). Evidence of significant endplate deformation differences between unaugmented and augmented FSU, while evident for the augmented endplate, was not present for the adjacent endplate. This non-invasive micro-CT method may also be useful to investigate endplate failure, and parameters that predict vertebral failure.

Cost-effectiveness of percutaneous vertebroplasty in osteoporotic vertebral fractures

A retrospective study was conducted in 179 consecutive patients (48 males, 131 females; mean age: 72.0 +/- 8.59 years; range: 51-93) with single symptomatic acute amyelic osteoporotic vertebral fracture presenting between September 2004 and September 2005 to the Santa Lucia Foundation in Rome, Italy. Vertebral fractures usually become manifest due to pain which can be debilitating. Treatment depends on the presence or absence of spinal cord involvement. In the first case, surgical stabilization is mandatory. In the second case, treatment may be performed either by conservative medical therapy (CMT) or percutaneous vertebroplasty (PVT). The aim of this study was to evaluate the effectiveness, costs and cost-effectiveness of percutaneous vertebroplasty. After 2 weeks of analgesic therapy, 153 patients presented refractory pain and were offered treatment by PVT. A total of 58 patients accepted and underwent PVT (PVT group), while 95 refused and underwent conservative medical therapy (CMT group). Follow-up was performed by specialist consults, spine radiography and MRI and a self-assessment questionnaire evaluating pain using a Visual Analogue Scale (VAS) and function using an ambulation and an Activities of Daily Living (ADL) scale. A 12-month follow-up was obtained in 86 of 95 (90.5%) CMT group patients and 54 of 58 (93.1%) PVT group patients. Significant reduction of VAS and improvement of ambulation and ADL was observed in both groups at 1 week and 3 and 12 months (P < 0.05; Wilcoxon signed rank test), however, these results were significantly superior in the PVT group at 1 week and 3 months (P < 0.05; Mann-Whitney U test). Average cost per patient at 1 week and 3 and 12 months were respectively 755.49 +/- 661.96, 3791.95 +/- 3341.97 and 4299.55 +/- 3211.53 euros (CMT group) and 3311.35 +/- 0.32, 3745.30 +/- 3.59 and 4101.05 +/- 755.41 euros (PVT group). PVT resulted significantly more cost-effective than CMT with regards to the three scales at 1 week (P < 0.05; Mann-Whitney U test). At 3 months PVT was more cost-effective than CMT with regards to the three scales, however, the difference was significant only with regards to ambulation. No significant differences in cost-effectiveness where found between the two groups at 12 months. PVT should be considered the treatment of first choice in symptomatic acute amyelic osteoporotic vertebral fractures with refractory pain after a short period of analgesic therapy.

Retrospective review of biopsy results following percutaneous fixation of vertebral compression fractures

BACKGROUND

Percutaneous vertebral body fixation has been found to provide pain relief and restoration of function for patients with compression fractures. Despite the prevalence of osteoporosis, there are a variety of aetiologies, such as lymphoma, myeloma or metastatic disease that may be responsible for the condition. In these instances, vertebral body biopsy can play an important role in determining fracture aetiology and assist in initiating concurrent medical treatment.

MATERIALS AND METHODS

Between 2002 and 2005, 80 vertebral body biopsies were performed in conjunction with percutaneous augmentation procedures on 50 patients at our teaching institution. Eleven biopsies were performed during vertebroplasty and 69 were performed during kyphoplasty. The mean age at the time of procedure was 75.7 years. Eight patients were male and 42 were female. A pathologist interpreted all biopsy samples and all charts were reviewed examining past history, diagnoses prior to compression fracture, biopsy results and post-op conditions that developed or were diagnosed after surgery.

RESULTS

All patients healed their compression fractures following surgery and no complications were experienced. Eleven patients had a diagnosis of osteoporosis prior to vertebral fracture, while 8 patients had a malignant condition initially suspected as being responsible for the compression fracture. Malignancy was identified in 4 patients, 3 of whom did not previously have such a diagnosis. In an additional 6 cases the suspected aetiology behind vertebral compression fracture was not confirmed by pathology.

DISCUSSION

This study found a 20% prevalence of malignancy in our population, which is higher than other reports in the literature. Eight percent of the patients in this study were ultimately found to have a malignant aetiology behind their compression fracture, while in 18% of the cases the presumed aetiology was not confirmed on pathological examination. Compression fractures can be one of the most common manifestations of osteoporosis, but a variety of other conditions, including neoplastic processes may also be responsible. As a result, we recommend obtaining a vertebral body biopsy prior to every vertebral augmentation procedure.

Comparative study of balloon kyphoplasty with unilateral versus bilateral approach in osteoporotic vertebral compression fractures

This study analyses the radiological and clinical results according to the two techniques of unilateral and bilateral balloon kyphoplasty in osteoporotic vertebral compression fractures. Fifty-two patients with osteoporotic vertebral compression fractures occurring at the thoracolumbar junction were enrolled in this study. All patients were classified into two groups; group I was treated with a unilateral approach and group II with a bilateral approach. The Cobb angle was measured each time to evaluate the kyphotic angle during the pre- and post-operative periods and at last follow-up, and a 10-point visual analog scale for pain was recorded at the same time. We found that the bilateral approach had a greater advantage in the reduction of kyphosis and the loss of reduction was less than the unilateral approach for the treatment of osteoporotic vertebral compression fractures.

Treatment of Painful Osteoporotic or Traumatic Vertebral Compression Fractures by Percutaneous Vertebral Augmentation Procedures

OBJECTIVE

Vertebroplasty (PV) and balloon kyphoplasty (KP) are minimally invasive vertebral augmentation procedures involving injection of polymethyl methacrylate cement under radiologic control into a fractured vertebral body. They strengthen the bone and improve the intense pain caused by fracture secondary to osteoporosis, metastasis, or trauma and refractory to conservative therapies such as analgesic use, bed rest, and bracing. Aim of the study is to investigate and compare safety and efficacy of KP and PV on pain and mobility in patients with vertebral fractures due to osteoporosis or trauma.

METHODS

Twenty-one patients have been enrolled in a prospective nonrandomized controlled study with painful vertebral compression fractures resistant to common therapies. Patients underwent KP or PV. A Visual Analog Scale has been used to measure pain status at different time up to 6 months; the Oswestry Disability Index (ODI) was chosen to evaluate functional activity before procedure and 6 months later.

RESULTS

Mean pain scores decreased significantly from pretreatment to posttreatment with KP and PV as did the ODI scores. No significant differences could be found between both groups for the mean VAS and ODI scores preprocedure and postprocedure. Cement extravasation occurred only during PV. No other adverse events correlated to both techniques have been reported.

DISCUSSION

Our results suggest that both PV and KP offer therapeutic benefit significantly reducing pain and improving mobility in patients with vertebral fracture without significant differences between groups in term of quality. The leakage of cement has been observed only during PV.

Transpedicle body augmenter in painful osteoporotic compression fractures

Osteoporotic compression fractures (VCFs) can result in progressive kyphosis and chronic pain. Polymethylmethacrylate has been used for augmentation of VCFs; however, there are cement complications, and long-term fracture healing is unknown. The transpedicle body augmenter (TpBA), a porous titanium spacer, has been reported as an internal support to reconstruct the vertebral body combining short segment fixation in burst fracture. We retrospectively reviewed radiographic and clinical results of TpBA vertebroplasty for single symptomatic VCF in 80 patients. Manual reduction and TpBA vertebroplasty via a paramedian incision with blunt dissection was done. Mean age was 72.3 years (range 51-87 years), and female-male ratio was 66:14. The mean symptom duration was 5 months, and follow-up 44 months. Peri-operative variables and radiographic and clinical results were evaluated. The average operation time was 26.1 min, blood loss 92 cc, and hospitalization 2.3 days. No patient had neurological deterioration. TpBA was found sinking into vertebral body initially, then locked by residual cortex, and finally stabilized within the vertebra. There was no dislodgement of TpBA in the final visit. Sixty-two patients (77.5%) could walk within 3-6 h after operation and the others within 24 h. The anterior vertebral restoration was 8.0 mm initially and 6.1 mm at final follow-up. Wedge angle correction was 11.5 degrees initially and 9.4 degrees at final follow-up. Pain, by the visual analog scale, was 8.6 pre-operatively, 2.5 at day 7 follow-up, and 2.9 at final follow-up. By the questionnaire, 72 of 76 respondents reported a decrease in discomfort after TpBA vertebroplasty, and 63 of 76 patients reported a return to normal activity after operation. The final satisfaction rate was 93.4%. TpBA vertebroplasty led to early and medium-term clinical improvement and anatomic restoration of painful VCFs.

Rapid and reliable biomechanical screening of injectable bone cements for autonomous augmentation of osteoporotic vertebral bodies: Appropriate values of elastic constants for finite element models

We performed finite element analysis studies on 3 three-dimensional representations of a single vertebral body: a regular cube, made of low-density polyurethane foam (foam cube analog); a regular cube considered composed of cancellous bone only (bone cube analog)); and the body of the L2 vertebra (full anatomical body model). Each finite element model was subjected to a compressive load of 2300 N, uniformly distributed over its superior surface. The cancellous and cortical bones were assigned anisotropic elastic properties, while the foam and the endplate material were considered to have isotropic properties. In each representation, the elastic properties of the material(s) were adjusted (from the initial values that were used) to give a stiffness of the representation that was equal to that of the mean result for fresh cadaveric osteoporotic single vertebral bodies, as obtained from ex vivo experimental studies reported in the literature (1226 +/- 996 N mm(-1)). Thus, any one of these representations, when used with the final adjusted value(s) of the elastic constants and modified to include a cylindrical hole filled with a specific volume of bolus of an injected bone cement, may be utilized in the rapid and reliable experimental ex vivo and/or numerical screening of these cements for use in autonomous vertebral body augmentation. This approach has many advantages over those that are currently being used, which are either characterization of the cement in isolation from the vertebral body or use of cadaveric vertebral bodies.

Efficacy and safety of balloon kyphoplasty in the treatment of vertebral compression fractures: a systematic review

The aim of this study is to evaluate the efficacy and safety of balloon kyphoplasty (BK) in the management of vertebral compression fractures (VCFs). This study is based on a systematic review of the literature (until October 2004) and meta-analysis of clinical studies assessing the efficacy and safety of BK in the treatment of VCFs. Estimates of effect were based on a random effects model. Meta-regression analyses were carried out where required. A total of 26 studies met the inclusion criteria. Although studies displayed considerable methodological limitations, the results of the clinical series indicate significant improvements in pain intensity, vertebral height, sagittal alignment, functional capacity, and quality of life. Compared with conventional medical management, BK afforded significant improvement in pain intensity and mobility. Likewise, a significant reduction was observed in vertebral collapse, kyphotic deformity, the development of new vertebral fractures, and hospital stay. Compared with vertebroplasty, the technique reduced the loss of height and the degree of kyphotic deformity, and afforded a significantly lower leakage rate-with no differences in relation to other variables. Regarding adverse effects, leakage affected 7% of all levels treated, while complications were recorded in 2% of the patients, and new vertebral fractures in 16%. The available evidence suggests that BK can be effective and safe in application to VCFs. However, existing studies evince substantial methodological limitations and relatively short follow-up periods. Better clinical research is required to determine the capacity of BK to avoid the functional and physiological sequelae of VCFs and to define the true role of the technique among the existing therapeutic options.

Sacral kyphoplasty for relieving pain caused by sacral hemangioma

STUDY DESIGN

Case report describing sacral kyphoplasty in a patient with sacral hemangioma; the first account of this procedure in a sacral hemangioma.

OBJECTIVES

To highlight the advantages of sacral kyphoplasty in the treatment of sacral tumors.

SETTING

This study is made in Baskent University in Turkey.

SUMMARY OF BACKGROUND DATA

Kyphoplasty and sacroplasty are new, minimally invasive techniques that are mostly used for treating osteoporotic vertebral body fractures. These techniques are very effective for achieving rapid pain relief and stabilizing the vertebra, and biopsy collection can be included in the procedure. The latter allows for informed treatment planning in patients with metastatic tumors.

METHOD

A 74-year-old woman with known metastatic renal cell carcinoma was investigated for pain in the left sacral region. A tumoral lesion was detected, and sacroplasty was performed at S1.

RESULTS

The sacral pain resolved completely after the procedure, and the patient was able to walk without assistance. The pathological diagnosis for the vertebral lesion was hemangioma.

CONCLUSIONS

Sacral kyphoplasty is a very effective, minimally invasive surgical procedure. Patients with debilitating diseases such as primary sacral tumors or metastases can be treated by this technique with no significant complications.

Arterial injury following percutaneous vertebral augmentation: a case report

STUDY DESIGN

Case report.

OBJECTIVE

To report a case of injury to a segmental branch of the L4 lumbar artery following kyphoplasty.

SUMMARY OF BACKGROUND DATA

To our knowledge, arterial injury following vertebral augmentation has not been described. The complications that have been reported rarely require additional intervention. The caliber of the fourth lumbar artery is such that injury to it, or to its more proximal branches, may cause significant morbidity.

METHODS

An 84-year-old female who presents 10 days after surgery from L5 kyphoplasty with pulsatile bleeding from the kyphoplasty site. An angiogram revealed an injury to a segmental branch of L4 lumbar artery.

RESULTS

A superselective angiogram was performed, followed by embolization of a branch of the L4 lumbar artery. This procedure successfully controlled the bleeding.

CONCLUSION

Surgeons performing percutaneous procedures for the augmentation of vertebral compression fractures are not able to visualize the arterial channels on the posterior aspect of the vertebral column. Although injury to these structures may be difficult to prevent, awareness of this complication will improve our response and decrease associated morbidity.

Anesthesia for Minimally Invasive Cranial and Spinal Surgery

The field of minimally invasive neurosurgery has evolved rapidly in its indications and applications over the last few years. New, less invasive techniques with low morbidity and virtually no mortality are replacing conventional neurosurgical procedures. Providing anesthesia for these procedures differs in many ways from conventional neurosurgical operations. Anesthesiologists are faced with the perioperative requirements and risks of newly developed procedures. This review calls attention to the anesthetic issues in various minimally invasive neurosurgical procedures for cranial and spinal indications. Among the procedures specifically discussed are endoscopic third ventriculostomy, endoscopic transsphenoidal hypophysectomy, endoscopic strip craniectomy, deep brain stimulation, video-assisted thorascopic surgery, vertebroplasty and kyphoplasty, cervical discectomy and foraminectomy, and laparoscopically assisted lumbar spine surgery.

Functional outcomes of kyphoplasty for the treatment of osteoporotic and osteolytic vertebral compression fractures

INTRODUCTION

Vertebral body compression fractures secondary to osteoporosis or malignant osteolysis are an increasingly common problem. The primary purpose of our study was to assess functional outcomes of kyphoplasty for the treatment of osteoporotic and osteolytic vertebral compression fractures. Our secondary purpose was to compare such functional outcomes in patients with osteoporosis versus multiple myeloma.

METHODS

The 314 consecutive patients prospectively included in our study had progressive and painful compression fractures as a result of osteoporosis or multiple myeloma that were refractory to nonoperative modalities. Of those 314 patients, the 211 (67.2%) patients (155 with osteoporosis and 56 with multiple myeloma) who had complete preoperative and postoperative data formed our final study group. All patients tolerated the kyphoplasty procedure well (that is, there were no adverse events in terms of perioperative patient condition). Follow-up ranged from 1 to 235 weeks (mean 55.0 weeks). Functional outcomes were assessed by the SF-36 and Oswestry Disability Index at baseline and at follow-up examinations. Data were analyzed by Student's t-test and the level of significance was set at P<or=0.05.

RESULTS

The average Owestry Disability Index score decreased by 12.6 points (P<0.001) in the overall group, by 11.8 points (P<0.001) at short-term follow-up, and by 8.6 points (P<0.001) at long-term follow-up. All SF-36 sub-scores except for general health and role-emotional showed statistically significant improvement from baseline values at the same time points. There was no statistically significant difference with regard to functional outcome in the osteoporosis and multiple myeloma sub-groups.

CONCLUSIONS

Kyphoplasty provided a safe and effective treatment for pain and disability in patients with verterbral compression fractures secondary to osteoporosis and multiple myeloma. In addition, we found no statistically significant difference with regard to functional outcome between patients with osteoporosis and multiple myeloma.

Kyphoplasty: 2 years of experience in a neurosurgery department

BACKGROUND

Kyphoplasty is a new technique to treat collapsed vertebral body (VB) fractures. The technique is very effective for achieving rapid pain relief, restoring bone height,and consequent vertebral realignment,and thus stabilization of the vertebra.

METHODS

We reviewed 57 patients with vertebral compression fractures. All patients were neurologically intact and presented with severe low back pain or localized pain over the thoracolumbar region. Indications for kyphoplasty were osteoporotic and traumatic compression fractures, osteolytic tumor metastases, and aggressive hemangiomas without spinal canal compression.

RESULTS

In 57 patients, 77 levels were treated. Follow-up was 6.5 months. Patients were evaluated with a visual analog scale (VAS) preoperatively and postoperatively. The mean preoperative VAS score was 91.08 for pain, whereas the mean postoperative VAS score was 11.22. Percentage of mean pain relief was 87.9% during the first 6 months of follow-up. We achieved a 43.6% improvement in the height of the compressed VB and 6.3 degrees of improvement in the kyphotic angle. No serious complications occurred. Mean hospital stay was 24 hours.

CONCLUSIONS

Kyphoplasty carries significantly less morbidity than vertebroplasty or open surgery. Risk for embolization is low. Normal kyphotic angle can be restored or improved by this technique. In the hands of experienced surgeons, kyphoplasty is a safe and a minimally invasive technique for patients with neoplastic, traumatic, or osteoporotic lesions of the vertebra or sacrum.

Combination kyphoplasty and spinal radiosurgery: a new treatment paradigm for pathological fractures

OBJECT

Patients with symptomatic pathological compression fractures require spinal stabilization surgery for mechanical back pain control and irradiation for the underlying malignant process. The authors evaluated a treatment paradigm of closed fracture reduction and fixation involving kyphoplasty and subsequent spinal radiosurgery.

METHODS

Twenty-six patients (six men and 20 women, mean age 72 years) with pathological compression fractures (16 thoracic and 10 lumbar) were prospectively evaluated. Histological diagnoses included 11 lung, nine breast, four renal, one cholangiocarcioma, and one ocular melanoma. Seven lesions had received prior external-beam radiation therapy. All patients underwent kyphoplasty that involved the percutaneous transpedicular technique. Fiducial markers allowing for image guidance during CyberKnife treatment were placed, at time of the kyphoplasty, in the pedicles at adjacent levels. Patients underwent single-fraction radiosurgery (mean time after kyphoplasty 12 days) in an outpatient setting. The tumor dose was maintained at 16 to 20 Gy (mean 18 Gy) to the 80% isodose line. The treated tumor volume ranged from 12.7 to 37.1 cm3. No acute radiation-induced toxicity or new neurological deficit occurred during the follow-up period (range 11-24 months, median 16 months). Axial pain improved in 24 (92%) of 26 patients.

CONCLUSIONS

The combined kyphoplasty and spinal radiosurgery treatment paradigm was found to be clinically effective in patients with pathological fractures; there was no significant spinal canal compromise. In this technique two minimally invasive surgical procedures are combined to avoid the morbidity associated with open surgery while providing both immediate fracture fixation and administering a single-fraction tumoricidal radiation dose.

Vertebroplasty and kyphoplasty: New treatment strategies for fractures in the osteoporotic spine

During the last decade, two new treatment modalities for osteoporotic vertebral fractures have gained more interest: percutaneous vertebroplasty and kyphoplasty. The techniques and the short-term clinical results and complications have been presented but there is no scientific evidence-based information regarding the efficacy of the procedures, such as randomized controlled trials (RCT). Instead, we have to rely on prospective and retrospective uncontrolled short-term observational studies and case-control studies. These studies have shown consistently that the short-term results after the procedures are favorable as regards both pain relief and functional status. It is currently unknown, however, whether a vertebroplasty or a kyphoplasty gives a better outcome than nonoperative treatment, and whether the long-term results are as favorable as the short-term results.

Treating Osteoporotic and Neoplastic Vertebral Compression Fractures with Vertebroplasty and Kyphoplasty

BACKGROUND

Compression fractures are common in patients with osteoporosis and cancer. In particular, vertebral compression fractures are crippling, and pose an additional risk of cord compression. Although a number of nonmedical options such as bracing and exercise programs may help these patients, the combination of constant, severe pain and spinal instability was until recently almost invariably synonymous with painful gradual deterioration and a poor quality of life. Vertebroplasty, and more recently kyphoplasty, are minimally invasive procedures that aim at limiting or reversing painful collapse of the vertebrae, while providing stability to the treated segment of the spine. As these new options are highly effective and involve minimal risk, it is important that physicians be familiar with them.

OBJECTIVE

This paper reviews the demographics of vertebral compression fractures, both osteoporotic and neoplastic, the technical aspects of vertebroplasty and kyphoplasty, and current results and outcomes.

RESULTS

Pain relief rates in excess of 90% have been reported with both vertebroplasty and kyphoplasty in patients with vertebral compression fractures. Procedural complication rates should be very low, in the 1%-2% range at most with proper technique.

CONCLUSIONS

Until the advent of vertebroplasty, almost no effective therapeutic option could be offered to patients suffering from neoplastic or osteoporotic vertebral compression fractures, which are relatively common and often crippling. The technical feasibility of these procedures is high, the risk low, and the effectiveness high. Therefore, it is important that physicians consider vertebroplasty and kyphoplasty as viable and strong options.

Vertebroplasty and Kyphoplasty for Treatment of Painful Osteoporotic Compression Fractures

PURPOSE

To review the pathophysiology of osteoporosis and describe vertebroplasty and kyphoplasty, which are minimally invasive procedures to treat the pain associated with vertebral compression fractures (VCFs).

DATA SOURCES

Extensive literature review of osteoporosis, vertebroplasty, and kyphoplasty supplemented by case study and clinical experience in the minimally invasive interventional neuroradiology interventions.

CONCLUSIONS

Osteoporosis is a progressive debilitating process that destroys the cancellous bone, weakening the overall integrity and stability of the bone. The loss of bone mass places the individual at increased risk for vertebral body, hip, and wrist fractures. In the past, there was no treatment option to repair vertebral body deformity or instability after osteoporotic VCFs. Management solely relied on the use of nonsteroidal anti-inflammatory drugs, narcotics, muscle relaxants, and/or orthotic bracing to provide pain relief. VCFs alter the stability of the vertebral body and column, and the lack of stabilization can lead to chronic pain syndrome, immobility, pulmonary compromise, progression of spinal deformity, increase in the risk for additional VCFs, and increase in the risk for comorbidities and mortality related to immobility.

IMPLICATIONS FOR PRACTICE

Vertebroplasty and kyphoplasty are minimally invasive procedures aimed at pain control, stabilization of the vertebral body, and with kyphoplasty, the ability to provide some correction of deformity with partial restoration of vertebral body height. Providing pain control and stabilization of the vertebral column improves mobility, thus decreasing the potential risks associated with immobility.

Immediate and early postoperative pain relief after kyphoplasty without significant restoration of vertebral body height in acute osteoporotic vertebral fractures

OBJECT

Painful osteoporotic vertebral compression fractures (VCFs) are a significant cause of disability in the elderly population. Kyphoplasty, a recently developed minimally invasive procedure, has been advocated for the successful management of these fractures in terms of immediate pain relief, and also for restoration of the premorbid level of daily activities. In this retrospective study the authors report on their experience with the early management of VCFs with kyphoplasty.

METHODS

A retrospective analysis was conducted in 13 patients (seven women and six men) whose ages ranged from 48 to 87 years (mean age 71.5 +/- 11 years [mean +/- standard deviation]). The interval between onset of symptoms and surgical intervention ranged from 4 to 9 weeks. Twenty levels (12 thoracic, eight lumbar) were treated in this cohort. Immediate and early postoperative (1-month follow-up visit) visual analog scale (VAS) pain scores, activity levels, and restoration of vertebral body (VB) height were assessed. The mean preoperative VAS score was 8 +/- 1, whereas the immediate and early postoperative scores were 1 +/- 1. These findings reflected a resolution of 90 to 100% of preoperative pain. All patients resumed routine activities within hours of the procedure, although improvement in VB height was not accomplished in this cohort. No major complications were encountered in this clinical series.

CONCLUSIONS

Kyphoplasty is a safe and effective method for the treatment of osteoporotic VCFs. Failure to restore VB height does not seem to interfere with the excellent pain management and good functional outcome provided by this procedure.