Faculty Bibliography

One hundred patients who underwent microlumbar diskectomy over 5 years were retrospectively reviewed. L4-5 and L5-S1 were compared to determine whether a patient's post-surgical outcome is related to the level where a herniation has occurred. Overall results included 70 excellent, 19 good, 2 fair, and 9 poor. Statistical analysis showed that neither the level involved, length of follow-up, nor degree of manual labor predicted outcome. Older patients and females tended to fare worse, but the trends were not significant. Three recurrent herniations occurred, 1 in the L4-L5 group and 2 in the L5-S1 group. No variable predicted recurrence

Open discectomy is the 'gold standard' for operative intervention in patients with herniated lumbar discs whose conservative treatment has failed. Over 60 years the indications for surgery and the expected success rates have been clearly elucidated. The specific patient selection and determination of surgical procedures continues to evolve. Recurrent herniations occur at a low rate, and serious complications are rare

The resurgence of pulmonary tuberculosis in the United States has been paralleled by a concomitant rise in tuberculosis of the spine (Pott's disease). The appearance of drug-resistant strains of tuberculosis, infection in large numbers of immunocompromised hosts, newer imaging modalities, and the development of more effective spinal reconstruction techniques have raised important issues regarding the management of Pott's disease. In spite of this, there has been little published recently on the modern management of Pott's disease in developed countries. We report our experience with the management of 20 patients with Pott's disease in the past 5 years, 16 of whom were admitted during the last 18 months of this retrospective study. The mean patient age was 49 years. Sixteen (80%) were men. Nineteen (95%) had a positive tuberculin skin test, and 13 (65%) had pulmonary tuberculosis. Symptoms consisted of spinal pain, weakness, sensory complaints, and flank mass in order of decreasing frequency. Ten patients were neurologically intact; the remainder had motor deficits of variable severity. The thoracic spine was involved in 13 patients, the lumbar spine was involved in 4, the cervical spine was involved in 2, and the thoracolumbar spine was involved in 1. Spinal deformity was present in 11 patients, spinal epidural compression was present in 13, and a paraspinal mass was present in 18. Operative indications included motor deficits, spinal deformity, nondiagnostic computer tomographic-guided needle biopsy, and noncompliance with, or lack of, response to medical therapy. Eleven patients underwent operations. Six patients had vertebrectomy and bone grafting with posterior instrumentation when indicated; three had laminectomy, debridement, and abscess drainage; one had laminectomy and posterior instrumentation; and one had paraspinal abscess drainage. Two patients have died; the remainder have been monitored for at least 1 year and are neurologically improved or normal without residual infection. The average angulation decreased from 31 to 24 degrees by the follow-up examination. In selected patients, early operative treatment with instrumentation, when indicated, minimizes neurological deterioration and spinal deformity, allows early ambulation, and results in excellent neurological outcome

Although posterior plates are increasingly used to manage cervical spinal instability, long-term follow-up evaluation of patients with a critical analysis of efficacy and complications has not been reported. The authors have retrospectively analyzed the outcome in 44 consecutive patients (37 males and seven females, age range 16 to 80 years) treated with posterior cervical plates. The indications for instrumentation were instability due to trauma in 42 cases, tumor in one, and infection in one. In four patients the follow-up period was limited to 3, 5, 11, and 16 months. Two patients died of chronic medical problems 4 and 9 months after treatment. The remaining 38 patients were followed from 2 to 6 years (mean 46 months). One motion segment was stabilized in 23 patients using two-hole plates; two motion segments were stabilized in the other 21 patients using three-hole plates. In the majority of patients (37 cases), supplemental bone grafting was not used. Patients were immobilized postoperatively in a Philadelphia collar. Solid arthrodesis was achieved in 39 (93%) of 42 patients. Three patients required revision of the cervical plating: in one patient with a C-5 burst fracture, two-hole plates were applied at C5-6 and progressive kyphosis mandated anterior fusion; the second patient required posterior wiring due to screw pull-out resulting from a technical error in screw insertion; the third patient, who refused to wear an orthosis postoperatively, also developed screw pull-out. In two patients who went on to spinal fusion, there was an increase in sagittal kyphosis (6 degrees and 8 degrees) without clinical sequelae. Screw loosening was noted in five patients, involving eight (3.8%) of the 210 lateral mass screws; this complication resulted in instrumentation failure or increased kyphosis in three cases. There were two superficial infections. This analysis indicates that posterior cervical plating is highly effective; at long-term follow-up review the cervical spine was successfully stabilized in 93% of cases. Plate failure was related to faulty screw placement, failure to include sufficient motion segments, and noncompliance with postoperative orthoses. Halo vest immobilization was unnecessary and supplemental bone grafting was generally not required for recent trauma

Anterior decompressive procedures have gained more widespread usage in the treatment of anterior compressive lesions of the spinal cord due to neoplasms. Alternative methods of vertebral body replacement that use a modified silastic tube placed into adjacent vertebral segments and filled with methyl methacrylate cement are described. The technique is reserved for patients with limited longevity as the result of the malignant nature of their disease process

Although occipitocervical fusion is frequently used for instability of the upper cervical spine and the occipitocervical articulation, most currently used techniques have one or more of the following disadvantages: the necessity for sublaminar wires, the use of occipital screws, a fixed angle of instrumentation, or the necessity for routine postoperative halo immobilization. Moreover, many reported techniques are associated with a high rate of nonunion or instrumentation failure. We present our experience with a technically simple method of obtaining rigid occipitocervical arthrodesis using a 5-mm malleable rod that is fixed to the skull by a pair of wires passed through four suboccipital burr holes. Segmental spinal fixation is achieved with Wisconsin interspinous wires and is occasionally supplemented with sublaminar wires. Supplemental autogenous bone graft is used in all cases. A cervical collar is routinely used for postoperative immobilization. The results of treatment were retrospectively reviewed in 16 patients with an average age of 49.4 years (range, 9-69). Mean follow-up was 24 months (range, 12-36 mo). The indication for fusion was instability of the occiput-C1-C2 complex as a result of Chiari malformation, rheumatoid disease, skull base tumor resection, basilar invagination, ankylosing spondylitis, Down's syndrome, cervical laminectomy, and trauma. The average number of levels fused was 5.4 (range, O-C3 to O-T3). Successful occipitocervical arthrodesis was achieved in all but one of the surviving patients. The single patient with a pseudarthrosis was successfully managed with supplemental bone grafting and halo immobilization. There were two deaths from medical complications in chronically ill patients. Other complications included one postoperative instrumentation loosening, one myocardial infarction, and one superficial occipital decubitus. In conclusion, rodding and segmental interspinous wiring is an effective, technically simple method of obtaining rigid occipitocervical fixation, which obviates the need for bulky orthoses