Harrington rod stabilization for pathological fractures of the spine

Kyphoplasty for patients with multiple myeloma is a safe surgical procedure: results from a large patient cohort

INTRODUCTION

Only in recent years has balloon kyphoplasty gained significance in the treatment of vertebral fractures as an adequate minimally invasive vertebral stabilization technique. Kyphoplasty has also increasingly been used to treat vertebral osteolyses caused by multiple myeloma (MM).

PATIENTS AND METHODS

In our cohort of 76 patients with MM with a total of 190 vertebral fractures treated with kyphoplasty, we performed a 30-day postoperative analysis of cement leakage, neurologic symptoms, pulmonary embolism, and infections.

RESULTS

Painful osteolytic or fractured vertebrae or even imminent vertebral instability caused by osteolyses were seen as indications for kyphoplasty. One case of pulmonary embolism was observed because of cement leakage as the only postoperative complication.

CONCLUSION

By careful interdisciplinary indication setting and a standardized treatment model, kyphoplasty presents a very safe and effective procedure for the treatment of vertebral osteolyses and fractures caused by MM.

Predictors of ambulatory function after decompressive surgery for metastatic epidural spinal cord compression

OBJECTIVE

Metastatic epidural spinal cord compression (MESCC) is a relatively common and debilitating complication of metastatic disease that often results in neurological deficits. This study was designed to explore associations with maintaining and regaining ambulatory function after decompressive surgery for MESCC.

METHODS

Seventy-eight patients undergoing decompressive surgery for MESCC at an academic tertiary care institution between 1995 and 2005 were retrospectively reviewed. Fisher's exact analysis was used to compare preoperative ambulatory and nonambulatory patients. Multivariate Cox proportional hazards regression was used to identify associations with either maintaining or regaining the ability to walk.

RESULTS

Patients were followed for 7.1 +/- 1.6 (mean +/- standard deviation) months after surgery. Preoperative nonambulatory patients required more extensive surgery (increased operative spinal levels and number of laminectomies) and had more surgical site complications (wound dehiscences and cerebrospinal fluid leaks) compared with preoperative ambulatory patients. From the multivariate analysis, preoperative ability to walk (relative risk [RR], 2.320; 95% confidence interval [CI], 1.301-4.416; P < 0.01) independently increased the likelihood of ambulation at the last follow-up evaluation 2.3-fold. Pathological vertebral compression fracture at presentation (RR, 0.471; 95% CI, 0.235-0.864; P = 0.01) independently decreased the likelihood of ambulation at the time of the last follow-up evaluation 2.1-fold. For patients unable to walk at the time of surgery, preoperative radiation therapy (RR, 0.406; 95% CI, 0.124-0.927; P = 0.03) decreased the likelihood of regaining the ability to walk 2.5-fold. Symptoms present for less than 48 hours (RR, 2.925; 95% CI, 1.133-2.925; P = 0.02) and postoperative radiotherapy (RR, 2.595; 95% CI, 1.039-8.796; P = 0.04) independently increased the likelihood of regaining ambulatory ability 2.9- and 2.6-fold, respectively, by the time of last follow-up evaluation.

CONCLUSION

The identification of these associations with neurological outcome may help guide in the preservation or return of ambulation after surgery for patients with MESCC.

Surgical management of spinal metastases: analysis of prognostic factors during a 10-year experience

OBJECT

Refinement of surgical techniques, especially anterior approaches, for the management of spinal metastases has improved patient outcomes, despite the fact that a complete analysis of the prognostic factors that would inform patient selection has not been undertaken. The authors sought to identify such prognostic factors for neurological outcome and life expectancy in patients with spinal metastases.

METHODS

The authors used Kaplan-Meier techniques, log-rank comparisons, and a multivariate model stratified by tumor type to identify prognostic factors for duration of ability to walk and survival in patients who underwent surgical treatment for spinal metastases during a decade when all current treatment options were available. Preoperatively, 53 (87%) of the 61 patients in the study population suffered neurological symptoms (for example, weakness) and 52 (85%) were ambulatory. Postoperatively, 59 (97%) were ambulatory. Most patients who survived 6 months (81%) remained ambulatory, as did 66% of those alive at 1.6 years. The median postoperative survival was 10 months. The risk factors for loss of ambulation were preoperative loss of ambulatory ability, recurrent or persistent disease after primary radiotherapy of the operative site, a procedure other than corpectomy, and tumor type other than breast cancer. Prognostic factors for reduced survival were surgical intervention extending over two or more spinal segments, recurrent or persistent disease after primary radiotherapy involving the operative site, diagnosis other than breast cancer, and a cervical spinal procedure.

CONCLUSIONS

The results of this analysis allowed the authors to create a simple prognostic factor scoring system that can be applied to individual patients. The positive experience derived from this study supports an expanded role for the surgical treatment of metastatic spinal disease.

Risk factors and probability of vertebral body collapse in metastases of the thoracic and lumbar spine

STUDY DESIGN

The associations between vertebral body collapse and the size or location of the metastatic lesions were analyzed statistically to estimate the critical point of collapse.

OBJECTIVES

To determine risk factors for collapse, to estimate the predicted probability of collapse under various states of metastatic vertebral involvement, and to establish the criteria of impending collapse.

SUMMARY OF BACKGROUND DATA

Pathologic vertebral collapse brings about severe pain and paralysis in patients with cancer. Prevention of collapse plays a significant role in maintaining or improving their quality of life. Because no previous study has clarified the critical point of vertebral collapse, however, the optimum timing for prophylactic treatment has been unclear.

METHODS

The size and location of metastatic tumor from Th1 to L5 were evaluated radiologically for 100 thoracic and lumbar vertebrae with osteolytic lesions. The correlations between collapse and the following risk factors (x1-x4) were determined by means of a multivariate logistic regression model: x1, tumor size (the percentage of tumor occupancy in the vertebral body [% TO]); x2, pedicle destruction, x3, posterior element destruction; and x4, costovertebral joint destruction.

RESULTS

Significant risk factors were costovertebral joint destruction (odds ratio, 10.17; P = 0.021) and tumor size (odds ratio of every 10% increment in %TO, 2.44; P = 0.032) in the thoracic region (Th1-Th10), whereas, tumor size (odds ratio of every 10% increment in %TO, 4.35; P = 0.002) and pedicle destruction (odds ratio, 297.08; P = 0.009) were main factors in the thoracolumbar and lumbar spine (Th10-L5). The criteria of impending collapse were: 50-60% involvement of the vertebral body with no destruction of other structures, or 25-30% involvement with costovertebral joint destruction in the thoracic spine; and 35-40% involvement of vertebral body, or 20-25% involvement with posterior elements destruction in thoracolumbar and lumbar spine.

CONCLUSIONS

With respect to the timing and occurrence of vertebral collapse, there is a distinct discrepancy between the thoracic and thoracolumbar or lumbar spine. When a prophylactic treatment is required, the optimum timing and method of treatment should be selected according to the level and extent of the metastatic vertebral involvement.

Single-stage posterior vertebrectomy and replacement combined with posterior instrumentation for spinal metastasis

The authors present a series of 25 patients who underwent single-stage complete spondylectomy, vertebral body reconstruction, and posterior segmental spinal stabilization for malignant metastatic disease involving multiple columns of the thoracolumbar spine. Patients were selected for this approach primarily because they were poor candidates for a transcavitary or lateral extracavitary approach or because the tumor involved both anterior and posterior columns of the spine. The operative approach used combines radical local resection of tumor via a bilateral transpedicular route, methylmethacrylate vertebral body reconstruction, and Luque rectangle stabilization in a single operation. Following surgery, the majority of patients experienced improvement in their neurological status, reduction in pain, or both. Most patients were functionally improved, or at least no worse, and spinal alignment was maintained in all. There was one local recurrence in a long-term survivor. Complications included cerebrospinal fluid fistulas, migrating graft material, and wound healing problems. The authors conclude that this surgical approach is safe and feasible for the radical resection of vertebral metastasis when combined with reconstruction and stabilization. This technique represents a useful alternative to other commonly used surgical approaches for the treatment of spinal metastases, and it should aid surgeons in selecting the optimum approach for individual patients.

Surgical treatment of extradural spinal cord compression due to metastatic tumours

The authors present a group of 23 patients with extradural spinal metastases who had undergone surgical treatment with different approaches, with reference to the anatomical site of the tumours. They report the results and discuss the criteria of the different surgical technical choices.

Anterior rib strut grafting for the treatment of malignant lesions in the thoracic spine

Anterior stabilization during thoracotomy, using the patient's own ribs, was carried out seven times in six subjects with malignant lesions of the thoracic vertebrae. The primary malignancy was lung carcinoma in four cases, thyroid carcinoma in one case, and alveolar soft tissue sarcoma in one. Resection of the lung tumor and spinal surgery were carried out simultaneously. Four of the six patients had complete paraplegia and two had partial paraplegia prior to the operation. After the decompression and anterior stabilization, three subjects responded well and three responded poorly because of respiratory insufficiency.

Stabilisation of the infected spine

A metal stabilising rod was inserted at the time of surgical drainage of the abscess in six patients with spinal instability secondary to vertebral osteomyelitis. The procedure enabled early postoperative mobilisation to be undertaken in five patients. All cases obtained immediate relief of pain. One case of delayed wound healing occurred but not late recurrent infections were encountered after discontinuing antibiotic therapy. The technique was employed in cases of pyogenic as well as tuberculous spinal osteomyelitis.

Treatment of metastatic disease of the spine with anterior resection and stabilization by means of a new cancellous metal construct. A preliminary report

Eleven patients with metastatic disease of the spine underwent anterior resection and stabilization with a new cancellous metal, keystone-shaped construct. Three are alive 1 year following surgery and seven at 6 months. One patient died postoperatively of pulmonary insufficiency. Ambulation was improved in all survivers. There was no dislocation of the construct.

Osteosarcoma

Osteosarcoma is the most common bone tumor of children and adolescents. The peak incidence of the disease is in the 15 to 19 year age group. The disease is more commonly seen in males than females. While several factors, including exposure to radiation, genetic disorders such as retinoblastoma, and high rate of bone growth, have been associated with osteosarcoma, in most cases no definite etiology can be established. Osteosarcoma usually originates in the metaphyseal region of long bones and extends through the cortex, causing varying degrees of bone destruction and expansion of periosteum. The radiographic appearance caused by this process is often referred to as "sun burst" sign. Positive diagnosis of osteosarcoma is made by histopathology. The histopathological classification of osteosarcoma can also predict the degree of aggressive behavior of this tumor and thus has prognostic significance. Surgery, including amputation or limb-salvage procedure, is the mainstay of treatment of osteosarcoma. It is now unequivocally established that adjuvant chemotherapy will prolong the survival of patients with this disease. Chemotherapy agents often used include platinum derivates, methotrexate, vincristine, cyclophosphamide, adriamycin, actinomycin D, bleomycin and DTIC. Depending on surgical decision, these agents can be used prior to or after the operation. Immediate fitting with prosthesis and provision of appropriate medical and psychological support in the care of these patients is essential.

Luque rod stabilization for metastatic disease of the spine

Instability of the spine caused by metastatic spread of primary tumors represents a serious risk for spinal cord or nerve root compression. In order to restore stability and relieve neural compression, a variety of surgical techniques originally used for reduction of nonpathologic spinal fractures have been applied to the problem of spinal metastases. Recently, we have utilized a technique developed primarily for correction of scoliosis to the treatment of metastatic spinal fractures. Six patients with spinal instability and neural compression secondary to metastatic tumors had segmental spinal stabilization with Luque rods, sublaminar wiring, and methyl methacrylate. Restoration of stability was successful in all cases with alleviation of preoperative pain and return to full activity. No evidence of instability occurred in this group of patients. As demonstrated by this experience and that of a few other small series, Luque rod stabilization provides a valuable addition to the techniques available for stabilization of metastatic fractures of the spine. Although the precise role of Luque rod segmental spinal stabilization in treatment of metastatic disease of the spine continues to be defined, thus far it has proved beneficial for cases of multiple vertebral body involvement or instability beyond one vertebral level.

Antitumor and antinociceptive approaches to control cancer pain

Patients with cancer pain often present with specific clinical syndromes that allow specific anti-tumor approaches. If these approaches are not feasible, neurosurgical procedures for pain relief should be considered. The major advantage of neurosurgical procedures is freedom from the excessive side effects of narcotic therapy. The most durable pain procedure is cordotomy, while intraspinal narcotics offer a rational treatment alternative in selected patients. Spinal and plexopathy syndromes that are amenable to more specific anti-tumor therapy should be looked for, since newer surgical approaches offer the prospect of both pain relief and tumor control.

The role of vertebral body collapse in the management of malignant spinal cord compression

The management of malignant spinal cord compression has been reviewed recently and attention drawn to the adverse effects of laminectomy. Data from that review suggested that the presence of vertebral body collapse could have an important negative effect on the outcome of laminectomy. However, there was only scant evidence available in the literature to support that conclusion. Eighty consecutive patients with thoracic spinal cord compression due to a single metastasis treated by laminectomy are reported here. It is seen that the presence of vertebral collapse signified: a much reduced chance of regaining the ability to walk; a much greater possibility of further neurological deterioration; and a major increase in the incidence of post-operative spinal instability. The role of laminectomy in the management of such patients needs to be further questioned and alternative therapeutic measures such as radiotherapy, posterior spinal instrumentation or anterior surgery should be strongly considered in the presence of vertebral body collapse.

Treatment of neoplastic epidural cord compression by vertebral body resection and stabilization

The results of treatment of neoplastic spinal cord compression by vertebral body resection and immediate stabilization in 101 consecutive patients over a 5-year period have been analyzed. Sites of primary cancer included the lung (25 patients), kidney (15 patients), breast (14 patients), connective tissue (12 patients), and a variety of others (35 patients). Of the 101 patients, 23 received surgery de novo; the remaining 78 patients had undergone previous therapy. Sites of involvement included the cervical region in 13 patients, the thoracic region in 68 patients, and the lumbar region in 20 patients. Prior to surgery, severe pain was noted in 90% of the patients, and 45% were non-ambulatory. Using an anterolateral surgical exposure, the vertebral body was resected along with all epidural tumor. Immediate stabilization was achieved with methyl methacrylate and Steinmann pins. Following surgery, the overall ambulation rate was 78%, and 85% of patients experienced pain relief. Of the 23 patients who had received no prior therapy, 90% continued to be ambulatory at their last follow-up examination or until death. The authors believe that surgery prior to irradiation is indicated in selected patients with neoplastic cord compression. In patients with solitary osseous metastasis to the spine, potentially curative resection can be undertaken if surgery is performed when the tumor is still confined to the vertebral body.