Faculty Bibliography

The anterior approach to the thoracic and lumbar spine for neoplastic disease is now a well-accepted procedure, with results, for the most part, superior to those achieved with laminectomy. However, the specific indications for anterior decompression and the selection of reconstruction techniques based on the location and extent of bony destruction have received surprisingly little attention. The authors report their experience with the operative management of 33 patients with benign and malignant tumors of the thoracic and lumbar spine, using the anterior transthoracic or retroperitoneal approach. The role of stabilization and the relative indications for anterior or posterior instrumentation are emphasized. The mean age of patients was 58 years. Twenty-three patients were male. Five patients had benign tumors, and the remainder had a variety of metastatic lesions. Twenty-nine patients had lower extremity motor deficits, although 25 were ambulatory preoperatively. Thirty-seven noncontiguous resections were performed in 33 patients. In 13 patients, the resected vertebral body was replaced with acrylic or bone without instrumentation; in 18, the acrylic was supplemented with anterior instrumentation; and in 6, both anterior and posterior instrumentation were used. Above T11, vertebral reconstruction techniques were used to restore stability after decompression. Between T11 and L4, anterior instrumentation was used to supplement vertebral reconstruction in all patients. Supplemental posterior instrumentation was used for three-column involvement. Motor function was stabilized or improved in 94% of patients, and 88% of patients were ambulatory postoperatively. Of 28 patients with malignant disease, 23 died after a mean survival of 10.2 months (range, 2-51 mo) and 5 are alive a mean of 34.4 months since their operation.(ABSTRACT TRUNCATED AT 250 WORDS)

We undertook a biomechanical study to compare the pullout strength of 3.5-mm AO screws placed in two different orientations within the bovine cervical spine. The first set of screws were oriented obliquely and passed through the lateral mass, as recommended by the AO group. The orientation of the second set was anterior to posterior through the lateral mass, as recommended by Roy-Camille. All screw holes were drilled and tapped by a spinal surgeon experienced with both techniques. Pullout force was measured on an Instron materials testing machine using a self-centering screw-holding chuck and loading rate of 0.833 mm/sec. Although the bone strength in the Roy-Camille orientation was greater (46.7 N/mm versus 36.1 N/mm, p < 0.05), the overall mean pullout force for the AO orientation was greater (607 N versus 471 N, p < 0.025) due to the longer length of bone available for screw purchase (17.0 mm versus 10.3 mm)

Prior irradiation and scarring can complicate wound closure following spinal surgery. Implanted tissue expanders were used six times in four patients to aid skin closure. Three patients had prior irradiation for cancer, and one had myelomeningocele. The average interval between placement and removal of the expanders was 46 days. Two late failures occurred because of prominent hardware. These expanders may provide adequate myocutaneous covers following spinal surgery in difficult cases

Cervical spine injuries pose devastating potential problems for surgeon and patient alike. This review will stress the early diagnosis of cervical spine injuries, with emphasis on early suspicion of injury. This review will focus on the radiology and types of lesions found with cervical spine injury

The indications and techniques for internal fixation of the lumbar spine in degenerative conditions have changed drastically since internal fixation was first applied to the spine almost 100 years ago. Anterior instrumentation and fusion may be used for repair of pseudarthrosis after posterolateral fusion; symptomatic lumbar scoliosis associated with degenerative disc disease; late pain secondary to posttraumatic kyphosis; postlaminectomy instability; and lumbar pain secondary to thoracolumbar kyphosis. Posterior instrumentation and fusion has been performed with Luque instrumentation over 3-4 levels in cases of multilevel instability. Combined anterior and posterior instrumentation and fusion are required for lumbosacral fusion in lumbar scoliosis with degenerative disease, and surgical correction of postsurgical lumbar kyphosis (flat-back syndrome). The techniques are demanding but with attention to detail can be performed with acceptably low-complication rates

Heterotopic ossification can impair the functional results of total hip arthroplasty. The causative role of trochanteric osteotomy in heterotopic ossification is uncertain. Postoperative radiographs of 100 total hip arthroplasties were analyzed for incidence of heterotopic ossification. Forty procedures were performed with trochanteric osteotomy and 60 without. There was a 17% overall incidence of clinically significant heterotopic ossification, 22% with osteotomy and 13% without. High- and low-risk categories revealed clinically significant heterotopic ossification in 25% of the high-risk group and in 8% of the low-risk group. In the high-risk group there was a 32% incidence with trochanteric osteotomy and 22% without osteotomy. In the low-risk group there was a 16% incidence without trochanteric osteotomy and a 3% incidence with trochanteric osteotomy. The increase in clinically significant heterotopic ossification in the high-risk group over that of the low-risk group was statistically significant. The present study showed that trochanteric osteotomy tended to increase the incidence and severity of clinically significant heterotopic ossification. These data suggest that trochanteric osteotomy should be avoided, if possible, during total hip arthroplasty to decrease the risk of heterotopic ossification