Percutaneous vertebral augmentation in metastatic disease: state of the art

Container Plasty in Advanced Painful Osteolytic Vertebral Metastases With Posterior Wall Defect: A Retrospective Observational Study

STUDY DESIGN

Review of mesh-container plasty (MCP) in osteolytic vertebral metastases.

OBJECTIVE

This study aims to assess the efficacy and safety of MCP in treating advanced vertebral metastases with posterior wall defects.

BACKGROUND

Diagnosis of vertebral metastases typically relies on the patient's tumor history, bone scans, or vertebral MRI. Surgical intervention often involves sampling vertebral body tissue for pathologic diagnosis. The revised Tokuhashi score is commonly used to predict survival time in patients with bone metastases. Outcome evaluation frequently employs the visual analog scale (VAS) and the Oswestry disability index (ODI) in assessing spinal surgery outcomes.

METHODS

A retrospective analysis included 111 patients treated between January 2014 and January 2018 in our hospital. Patients were categorized into 2 groups: MCP group (n=51) and PVP group (n=60). Grades based on the percentage of posterior wall defect area were established: grade I (≤25%), grade II (26% to 50%), grade III (51% to 75%), and grade IV (76% to 100%). Efficacy was assessed using VAS and ODI.

RESULTS

Both MCP and PVP groups exhibited significant pain relief and improved motor function. No significant differences were observed in VAS and ODI scores at any follow-up point (P>0.05). In the MCP group, bone cement leakage occurred in 13 cases, with a leakage rate of 25.49%. However, none of the patients experienced clinical or neurological symptoms. In the PVP group, bone cement leakage occurred in 50% of patients, with 6 patients developing neurological symptoms. Significant differences between the groups were observed in major complications related to bone cement leakage (P=0.03).

CONCLUSION

MCP demonstrates efficacy in pain relief and safety in treating vertebral metastases with deficient posterior walls. It represents a promising option for spinal surgeons managing vertebral metastases with posterior wall deficiencies.

The role of percutaneous vertebral augmentation in patients with metastatic breast cancer: Literature review including report of two cases

Patients with metastatic breast cancer are at high risk for developing vertebral compression fractures due to underlying bone metastases and bone density loss. Vertebral augmentation techniques including percutaneous vertebroplasty and percutaneous balloon kyphoplasty are techniques used to stabilize compression fractures and improve pain. However, rare complications from these interventions have been observed, including spinal cord compression, nerve root compression, venous cement embolism, and pulmonary cement embolism. These complications pose unique potential challenges for patients with cancer who may already have decreased lung function and potential for venous thromboembolism. In this review, we first describe the role of percutaneous vertebral augmentations in patients with metastatic cancer, with a particular focus on patients with breast cancer. Then, we describe complications of vertebral augmentation in two patients with metastatic breast cancer including long-term symptomatic and radiographic follow-up.

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Balloon kyphoplasty and percutaneous vertebroplasty are used to stabilize compression fractures and improve pain.

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Leakage of bone cement can cause cement emboli which can depsit in locations such as the pulmonary and renal vasculature.

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Management of cement emboli depends on the amount of cement embolized and the severity of symptoms.

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Future studies are needed to better understand the long-term radiographic and clinical consequences of cement emboli.

Adult Cancer Pain, Version 3.2019, NCCN Clinical Practice Guidelines in Oncology

In recent years, the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Adult Cancer Pain have undergone substantial revisions focusing on the appropriate and safe prescription of opioid analgesics, optimization of nonopioid analgesics and adjuvant medications, and integration of nonpharmacologic methods of cancer pain management. This selection highlights some of these changes, covering topics on management of adult cancer pain including pharmacologic interventions, nonpharmacologic interventions, and treatment of specific cancer pain syndromes. The complete version of the NCCN Guidelines for Adult Cancer Pain addresses additional aspects of this topic, including pathophysiologic classification of cancer pain syndromes, comprehensive pain assessment, management of pain crisis, ongoing care for cancer pain, pain in cancer survivors, and specialty consultations.

Primary Ewing's sarcoma of the vertebral body: A case report

RATIONAL

The occurrence of Ewing's sarcoma in the vertebral body of elderly women is extremely rare, and the case of Ewing's sarcoma in the spine with secondary surgical repair after wrong diagnosis and treatment has not been reported. We report a case involving primary Ewing's sarcoma of the vertebral body in an elderly female. Owing to its rarity and controversial issues, we report a case report to discuss its clinical features, treatments, radiological, and histological characteristics.

PATIENT CONCERNS

The elderly female patient came to see us with the manifestation of total paralysis of both lower limbs. The patient with a vertebral compression fracture as the primary manifestation was misdiagnosed in another hospital. The patient underwent inappropriate surgical treatment and was transferred to our hospital for diagnosis and second-stage surgery.

DIAGNOSES

The postoperative pathological examination and immunohistochemical examination in our hospital confirmed: Ewing's sarcoma; Surgical history at other hospitals suggests: after Bone cement injection.

INTERVENTIONS

The patient underwent a T6 and T8 laminectomy and T5/6-T9 pedicle screw fixation.

OUTCOMES

Reexamination 1 month after the surgery showed that the tumor had been partially resected, the spinal cord compression was relieved, the tumor did not grow further, and the patient's lower limb physical ability, tactile sense, algesia and temperature sense recovered slightly.

LESSONS

For patients with ewing's tumor in the spinal canal with symptoms of spinal cord compression, even if the patients with poor results after a unadvisable operation, it is still necessary to be actively in spinal cord compression by surgery. The differential diagnosis of Ewing's sarcoma and compression fractures is very important. For patients with vertebral tumors, special attention should be taken during vertebroplasty for bone cement leakage caused by excessive bone cement injection and increased local pressure. And some experience with imaging and laboratory findings.

Use of Cement-Augmented Percutaneous Pedicular Screws in the Management of Multifocal Tumoral Spinal Fractures

STUDY DESIGN

Retrospective case series observational study.

PURPOSE

Cancer patients are often aged and are further weakened by their illness and treatments. Our goal was to evaluate the efficiency and safety of using minimally invasive techniques to operate on spinal fractures in these patients.

OVERVIEW OF LITERATURE

Vertebroplasty is now considered to be a safe technique that allows a significant reduction of the pain induced by a spinal tumoral fracture. However, few papers describe the kyphosis reduction that can be achieved by combining percutaneous fixation and anterior vertebral reconstruction.

METHODS

We studied 35 patients seen between December 2013 and October 2016 who had at least one pathological spinal fracture and multiple vertebral metastases. The population's mean age was 67 years, and no patients included had preoperative neurological deficits. The patients underwent a minimally invasive surgery consisting of a percutaneous pedicular fixation with cement-enhanced screws and anterior reconstruction comprising kyphoplasty when possible or corpectomy in cases of excessive damage to the vertebral body. Back pain, traumatic local and regional kyphosis, and Beck's Index were collected pre- and postoperatively, and at 3-, 6-, and 12-month follow-ups.

RESULTS

Mean follow-up time was 13.4 months. Significant reductions in back pain (p<0.001) and local (p<0.001) and regional kyphosis (p=0.006) were found at the 6-month follow-up (alpha risk level <0.05). Beck's Index was also significantly increased, indicating good restoration of the anterior vertebral height. By the final follow-up, no screws had fallen/pulled out. There were no infectious or neurological complications.

CONCLUSIONS

Percutaneous cement-enhanced fixation for pathological fractures has proven a safe and efficient technique in our experience, enabling weak patients to rapidly become ambulatory again without complications. Further follow-up of the patients is necessary to assess the long-term effects of this technique and the continued quality of life of our patients.

Percutaneous Vertebroplasty Relieves Pain in Cervical Spine Metastases

Percutaneous vertebroplasty (PVP) has been shown to release spinal pain and stabilize the vertebral body. PVP is suggested as an alternative treatment in spinal metastasis. Although cervical metastases is less prevalent than thoracic and lumbar spine, PVP procedure in cervical vertebrae remains technical challenging. We retrospectively analyzed the data from patients (n = 9) who underwent PVP using anterolateral approach to treat severe neck pain and restricted cervical mobility from metastatic disease. Patients were rated using modified Tokuhashi score and Tomita score before the procedure. Visual analog scale (VAS), neck disability index (NDI), analgesic use, and imaging (X-ray or CT) were evaluated before PVP and 3 days, 3 months, and 6 months after PVP. All patients were in late stage of cancer evaluated using modified Tokuhashi and Tomita score. The cement leakage rate was 63.6% (14 of the 22 vertebrae) with no severe complications. VAS, NDI, and analgesic use were significantly decreased 3 days after the procedure and remained at low level until 6 months of follow-up. Our result suggested PVP effectively released the pain from patients with cervical metastasis. The results warrant further clinical investigation.

Application of digital volume correlation to study the efficacy of prophylactic vertebral augmentation

BACKGROUND

Prophylactic augmentation is meant to reinforce the vertebral body, but in some cases it is suspected to actually weaken it. Past studies only investigated structural failure and the surface strain distribution. To elucidate the failure mechanism of the augmented vertebra, more information is needed about the internal strain distribution. This study aims to measure, for the first time, the full-field three-dimensional strain distribution inside augmented vertebrae in the elastic regime and to failure.

METHODS

Eight porcine vertebrae were prophylactically-augmented using two augmentation materials. They were scanned with a micro-computed tomography scanner (38.8μm voxel resolution) while undeformed, and loaded at 5%, 10%, and 15% compressions. Internal strains (axial, antero-posterior and lateral-lateral components) were computed using digital volume correlation.

FINDINGS

For both augmentation materials, the highest strains were measured in the regions adjacent to the injected cement mass, whereas the cement-interdigitated-bone was less strained. While this was already visible in the elastic regime (5%), it was a predictor of the localization of failure, which became visible at higher degrees of compression (10% and 15%), when failure propagated across the trabecular bone. Localization of high strains and failure was consistent between specimens, but different between the cement types.

INTERPRETATION

This study indicated the potential of digital volume correlation in measuring the internal strain (elastic regime) and failure in augmented vertebrae. While the cement-interdigitated region becomes stiffer (less strained), the adjacent non-augmented trabecular bone is affected by the stress concentration induced by the cement mass. This approach can help establish better criteria to improve vertebroplasty.

A PRELIMINARY IN VITRO BIOMECHANICAL EVALUATION OF PROPHYLACTIC CEMENT AUGMENTATION OF THE THORACOLUMBAR VERTEBRAE

In this paper, the biomechanical effectiveness of prophylactic augmentation in preventing fracture was investigated. In vitro biomechanical tests were performed to assess which factors make prophylactic augmentation effective/ineffective in reducing fracture risk. Nondestructive and destructive in vitro tests were performed on isolated osteoporotic vertebrae. Five sets of three-adjacent-vertebrae were tested. The central vertebra of each triplet was tested in the natural condition (control) non-destructively (axial-compression, torsion) and destructively (axial-compression). The two adjacent vertebrae were first tested nondestructively (axial-compression, torsion) pre-augmentation; prophylactic augmentation (uni- or bi-pedicular access) was then performed delivering 5.04[Formula: see text]mL to 8.44[Formula: see text]mL of acrylic cement by means of a customized device; quality of augmentation was CT-assessed; the augmented vertebrae were re-tested nondestructively (axial-compression, torsion), and eventually loaded to failure (axial-compression). Vertebral stiffness was correlated with the first-failure, but not with ultimate failure. The force and work to ultimate failure in prophylactic-augmented vertebrae was consistently larger than in the controls. However, in some cases the first-failure force and work in the augmented vertebrae were lower than for the controls. To investigate the reasons for such unpredictable results, the correlation with augmentation quality was analyzed. Some augmentation parameters seemed more correlated with mechanical outcome (statistically not-significant due to the limited sample size): uni-pedicular access resulted in a single cement mass, which tended to increase the force and work to first- and ultimate failure. The specimens with the highest strength and toughness also had: at least 25% cement filling, cement mass shifted anteriorly, and cement-endplate contact. These findings seem to confirm that prophylactic augmentation may aid reducing the risk of fracture. However, inadequate augmentation may have detrimental consequences. This study suggests that, to improve the strength of the augmented vertebrae, more attention should be dedicated to the quality of augmentation in terms of amount and position of the injected cement.

The era of stereotactic body radiotherapy for spinal metastases and the multidisciplinary management of complex cases

Spinal metastases are increasingly becoming a focus of attention with respect to treating with locally "ablative" intent, as opposed to locally "palliative" intent. This is due to increasing survival rates among patients with metastatic disease, early detection as a result of increasing availability of spinal MRI, the recognition of the oligometastatic state as a distinct sub-group of favorable metastatic patients and the advent of stereotactic body radiotherapy (SBRT). Although conventionally fractionated radiation therapy has been utilized for decades, the rates of complete pain relief and local control for complex tumors are sub-optimal. SBRT has the advantage of delivering high total doses in few fractions (typically, 24 Gy in 1 or 2 fractions to 30-45 Gy in 5 fractions) that can be considered "ablative". With mature clinical experience emerging among early adopters, we are realizing beyond efficacy the limitations of spine SBRT. In particular, toxicities such as vertebral compression fracture, and epidural disease progression as the most common pattern of local tumor progression. As a result, the multidisciplinary evaluation of cases prior to SBRT is emphasized with the intent to identify patients who could benefit from surgical stabilization or down-staging of epidural disease. The purpose of this review is to provide an overview of the current literature with respect to outcomes, technical details for safe delivery, patient selection criteria, common and uncommon side effects of therapy, and the increasing use of minimally invasive surgical techniques that can improve both safety and local control.

Spine metastases: are minimally invasive surgical techniques living up to the hype?

Surgery is still considered the mainstay treatment of spine metastases. However, conventional surgery is associated with a high complication rate that may delay the initiation of adjuvant therapies and make some patients not eligible. Minimally invasive surgical techniques have been developed to overcome these drawbacks while providing the same benefits than standard open surgery. In recent years, there has been a flourishing enthusiasm demonstrating the advantages of these various techniques. Although, it is clear that these techniques have greatly improved the treatment of spine metastases, each has its own limitations. In this report, we list the main minimally invasive surgical techniques emphasizing their advantages and drawbacks.

Vertebral augmentation for neoplastic lesions with posterior wall erosion and epidural mass

BACKGROUND AND PURPOSE

The presence of a cortical erosion of the posterior wall or an epidural mass is commonly considered a contraindication to performing a vertebral augmentation, considering the perceived increased risk of an epidural cement leak. Our aim was to assess technical and clinical complications of vertebral augmentation procedures performed for pain palliation and/or stabilization of neoplastic lytic vertebral body lesions, with cortical erosion of the posterior wall, often associated with a soft-tissue epidural mass.

MATERIALS AND METHODS

In 48 patients, we performed retrospective vertebral augmentation assessment on 70 consecutive levels with cortical erosion of the posterior wall, as demonstrated by preprocedural CT/MR imaging. An epidural mass was present in 31/70 (44.3%) levels. Cavity creation was performed with Coblation Wands before cement injection in 59/70 levels. Injection of high-viscosity polymethylmethacrylate was performed under real-time continuous fluoroscopic control. Postprocedural CT of the treated levels was performed in all cases. Clinical follow-up was performed at 1 and 4 weeks postprocedurally.

RESULTS

In 65/70 (92.8%) levels, the vertebral augmentation resulted in satisfactory polymethylmethacrylate filling of the lytic cavity and adjacent trabecular spaces in the anterior half of the vertebral body. An epidural leak of polymethylmethacrylate occurred in 10/70 (14.2%) levels, causing radicular pain in 3 patients, which spontaneously resolved within 1 week in 2 patients, while 1 patient with a T1-T2 foraminal leak developed severe weakness of the intrinsic hand muscles and a permanent motor deficit.

CONCLUSIONS

In our series of vertebral augmentation of neoplastic lytic vertebral lesions performed for palliation of pain and/or stabilization, we observed a polymethylmethacrylate epidural leak in only 14.2% of levels, despite the presence of cortical erosion of the posterior wall and an epidural mass, with an extremely low rate of clinical complications. Our data seem to justify use of vertebral augmentation in patients with intractable pain or those at risk for vertebral collapse.

EXPERIMENTAL METHODS FOR THE BIOMECHANICAL INVESTIGATION OF THE HUMAN SPINE: A REVIEW

In vitro mechanical testing of spinal specimens is extremely important to better understand the biomechanics of the healthy and diseased spine, fracture, and to test/optimize surgical treatment. While spinal testing has extensively been carried out in the past four decades, testing methods are quite diverse. This paper aims to provide a critical overview of the in vitro methods for mechanical testing the human spine at different scales. Specimens of different type are used, according to the aim of the study: spine segments (two or more adjacent vertebrae) are used both to investigate the spine kinematics, and the mechanical properties of the spine components (vertebrae, ligaments, discs); single vertebrae (whole vertebra, isolated vertebral body, or vertebral body without endplates) are used to investigate the structural properties of the vertebra itself; core specimens are extracted to test the mechanical properties of the trabecular bone at the tissue-level; mechanical properties of spine soft tissue (discs, ligaments, spinal cord) are measured on isolated elements, or on tissue specimens. Identification of consistent reference frames is still a debated issue. Testing conditions feature different pre-conditioning and loading rates, depending on the simulated action. Tissue specimen preservation is a very critical issue, affecting test results. Animal models are often used as a surrogate. However, because of different structure and anatomy, extreme caution is required when extrapolating to the human spine. In vitro loading conditions should be based on reliable in vivo data. Because of the high complexity of the spine, such information (either through instrumented implants or through numerical modeling) is currently unsatisfactory. Because of the increasing ability of computational models in predicting biomechanical properties of musculoskeletal structures, a synergy is possible (and desirable) between in vitro experiments and numerical modeling. Future perspectives in spine testing include integration of mechanical and structural properties at different dimensional scales (from the whole-body-level down to the tissue-level) so that organ-level models (which are used to predict the most relevant phenomena such as fracture) include information from all dimensional scales.

Strain distribution in the lumbar vertebrae under different loading configurations

BACKGROUND CONTEXT

The stress/strain distribution in the human vertebrae has seldom been measured, and only for a limited number of loading scenarios, at few locations on the bone surface.

PURPOSE

This in vitro study aimed at measuring how strain varies on the surface of the lumbar vertebral body and how such strain pattern depends on the loading conditions.

METHODS

Eight cadaveric specimens were instrumented with eight triaxial strain gauges each to measure the magnitude and direction of principal strains in the vertebral body. Each vertebra was tested in a three adjacent vertebrae segment fashion. The loading configurations included a compressive force aligned with the vertebral body but also tilted (15°) in each direction in the frontal and sagittal planes, a traction force, and torsion (both directions). Each loading configuration was tested six times on each specimen.

RESULTS

The strain magnitude varied significantly between strain measurement locations. The strain distribution varied significantly when different loading conditions were applied (compression vs. torsion vs. traction). The strain distribution when the compressive force was tilted by 15° was also significantly different from the axial compression. Strains were minimal when the compressive force was applied coaxial with the vertebral body, compared with all other loading configurations. Also, strain was significantly more uniform for the axial compression, compared with all other loading configurations. Principal strains were aligned within 19° to the axis of the vertebral body for axial-compression and axial-traction. Conversely, when the applied force was tilted by 15°, the direction of principal strain varied by a much larger angle (15° to 28°).

CONCLUSIONS

This is the first time, to our knowledge, that the strain distribution in the vertebral body is measured for such a variety of loading configurations and a large number of strain sensors. The present findings suggest that the structure of the vertebral body is optimized to sustain compressive forces, whereas even a small tilt angle makes the vertebral structure work under suboptimal conditions.

Painful boney metastases

Boney metastasis may lead to terrible suffering from debilitating pain. The most likely malignancies that spread to bone are prostate, breast, and lung. Painful osseous metastases are typically associated with multiple episodes of breakthrough pain which may occur with activities of daily living, weight bearing, lifting, coughing, and sneezing. Almost half of these breakthrough pain episodes are rapid in onset and short in duration and 44% of episodes are unpredictable. Treatment strategies include: analgesic approaches with "triple opioid therapy", bisphosphonates, chemotherapeutic agents, hormonal therapy, interventional and surgical approaches, steroids, radiation (external beam radiation, radiopharmaceuticals), ablative techniques (radiofrequency ablation, cryoablation), and intrathecal analgesics.

Interobserver agreement for the spine instability neoplastic score varies according to the experience of the evaluator

OBJECTIVES

To evaluate the interobserver agreement for the Neoplastic Spine Instability Score (SINS) among spine surgeons with or without experience in vertebral metastasis treatment and physicians in other specialties.

METHODS

Case descriptions were produced based on the medical records of 40 patients with vertebral metastases. The descriptions were then published online. Physicians were invited to evaluate the descriptions by answering questions according to the Neoplastic Spine Instability Score (SINS). The agreement among physicians was calculated using the kappa coefficient.

RESULTS

Seventeen physicians agreed to participate: three highly experienced spine surgeons, seven less-experienced spine surgeons, three surgeons of other specialties, and four general practitioners (n = 17). The agreement for the final SINS score among all participants was fair, and it varied according to the SINS component. The agreement was substantial for the spine location only. The agreement was higher among experienced surgeons. The agreement was nearly perfect for spinal location among the spine surgeons who were highly experienced in vertebral metastases.

CONCLUSIONS

This study demonstrates that the experience of the evaluator has an impact on SINS scale classification. The interobserver agreement was only fair among physicians who were not spine surgeons and among spine surgeons who were not experienced in the treatment of vertebral metastases, which may limit the use of the SINS scale for the screening of unstable lesions by less-experienced evaluators.

Overview of Diagnosis and Management of Metastatic Disease to Bone

Background

Bone metastases occur frequently in patients with advanced cancer and are a serious complication of cancer. The decision to treat is often individualized, based on each patient's clinical presentation, life expectancy, and quality of life.

Methods

We reviewed the current literature pertaining to management of metastatic disease to bone, and the medical, radiotherapeutic, and surgical treatment options for management of bone metastasis are discussed.

Results

Current management of skeletal metastasis includes analgesia, systemic therapy, radiation therapy, and surgery. We propose treatment algorithms for management of vertebral and nonvertebral bone metastases and suggest individualized interventions based on clinical presentation.

Conclusions

Management of bone metastases is complex and requires a multidisciplinary approach. The goal of treatment is often palliative, and intervention and treatment regimens should be individualized based on the specific clinical presentation of each patient.

Percutaneous vertebral augmentation for painful osteolytic vertebral metastasis: a case report

INTRODUCTION

Vertebral metastases are associated with significant pain, disability, and morbidity. Open surgery for fracture stabilization is often inappropriate in this population due to a poor risk-benefit profile, particularly if life expectancy is short. Percutaneous vertebroplasty and kyphoplasty are appealing adjunctive procedures in patients with malignancy for alleviation of intractable pain. However, these patients have higher risk of serious complications, notably cement extravasation. Described in this report is a case of a painful osteolytic vertebral metastasis that was successfully treated by a novel percutaneous vertebral augmentation system.

CASE PRESENTATION

A 42-year-old Caucasian female presented with a history of metastatic lung cancer unresponsive to radiation and chemotherapy with symptoms inadequately controlled by opiates over the previous 6 months. Magnetic resonance imaging and spiral computed tomography with two-dimensional reconstruction showed an osteolytic vertebral metastasis with complete involvement of the T10 vertebral body, extending to the cortical vertebral wall anteriorly and posteriorly. The patient was treated with percutaneous vertebral augmentation (Kiva® VCF Treatment System, Benvenue Medical, Inc, Santa Clara, CA) utilizing a novel coil-shaped polyetheretherketone implant designed to minimize the risk of cement extravasation. After the minimally invasive procedure, bone cement distribution within the vertebral body was ideal, with no observed cement extravasation. No complications were reported, pain completely resolved within 24 hours, and use of intravenous narcotics was progressively diminished within 1 week. Complete pain relief was maintained throughout 4 months of follow-up.

CONCLUSION

The Kiva System represents a novel and effective minimally invasive treatment option for patients suffering from severe pain due to osteolytic vertebral metastasis.

Palliative considerations in the surgical treatment of spinal metastases: evaluation of posterolateral decompression combined with posterior instrumentation

PURPOSE

To evaluate the outcome of patients with spinal metastases, treated under palliative considerations by spinal decompression and sole posterior instrumentation, in respect to survival, neurological symptomatology, pain, ECOG grade, and Tomita's prognostic score (TPS).

PATIENTS AND METHODS

Fifty-seven consecutive patients with metastatic vertebral tumors were treated using a posterolateral approach for decompression combined with posterior instrumentation. Mean age was 58.6 years. In average, 3.4 vertebral segments were involved in instrumentation.

RESULTS

Preoperative mean TPS was 5.9. The majority of the patients (70.2%) presented with an ECOG grade ≤2. The distribution of the metastatic lesions that needed surgical treatment was: 7.8% cervical, 60.9% thoracical, and 31.3% lumbar. In 52.6% the tumor led to pathological vertebral fractures. Mean pain VAS scores improved significantly in all but one patient from 6.6 preoperatively to 3.1 postoperatively. Post-surgical Frankel grades decreased. Mean postoperative survival was 11.4 months. Ten patients survived until now. Forty-seven patients have died with a mean survival of 9 months. Complication rate was only 5.3% with two superficial wound infections and one seroma. Not a single case of posterior spinal instrumentation fatigue failure was detected.

CONCLUSIONS

Palliative surgical treatment for metastatic spinal tumors using a decompressive posterolateral approach combined with sole posterior instrumentation achieved convincing clinical results. All patients with intractable pain showed significant improvement postoperatively, and neurological deterioration was avoided. Since patients with spinal metastases enter the terminal stage of their disease, it is generally agreed that they require only palliative surgical treatments. Accordingly, spinal decompression and stabilization may be performed to improve the quality of the remaining life of cancer patients.