Early failure of long segment anterior cervical plate fixation.

A retrospective, multicenter study was undertaken to evaluate the early postoperative failure rate of long segment anterior cervical fusion and plating to stabilize the cervical spine after a two- or three-level corpectomy for degenerative, traumatic, and neoplastic diseases of the cervical spine. Patient demographic factors as well as technical factors such as bone graft placement, plate and screw position, and postoperative brace immobilization were analyzed. During the early postoperative period, the graft/plate construct dislodged in 3 of 33 patients with a two-level corpectomy and fusion (9%) compared with 6 of 12 patients with a three-level corpectomy and fusion (50%). The difference in failure rates after a three- versus two-level corpectomy and fusion was statistically significant (p < 0.05). A higher early failure rate was also seen with failure to correctly lock the screws to the plate and the use of a peg-in-hole type bone grafting technique, although these differences were not statistically significant. Although several technical and patient-specific factors may contribute to this, anterior cervical plating and bone grafting alone after a three-level cervical corpectomy for various spinal disorders appears to afford inadequate stability in the early postoperative period, regardless of immobilization methods.

The role of anterior surgery in the treatment of thoracolumbar fractures.

Operative treatment of thoracolumbar burst fractures or fracture dislocations is a relatively modern development. Anterior decompression and stabilization play a significant role in the treatment of thoracolumbar burst fractures. This article reviews the clinical indications and describes a one-staged operative technique for anterior instrumentation following anterior decompression.

Formant frequency characteristics of elderly speakers in contextual speech.

The present study measured F1 and F2 formant frequency levels of elderly and young male and female speakers producing the /i/, /ae/, [symbol: see text], /u/, and /a/ vowels in two carrier phrases. Results of a series of ANOVAs showed significant interactions of speaker age x vowel for both F1 and F2 formant frequencies for the male and female speakers. Results suggested that while elderly male speakers exhibit significant alterations in vowel production during contextual speech, elderly female speakers generally maintain formant frequency integrity or appropriate articulatory posturing during contextual vowel productions.

Modification of technique and results of atlantoaxial transfacet stabilization.

A modification of the C1 C2 transfacet stabilization is reported. This technique allows a smaller incision to be made and provides a method for easier screw insertion.

Primary treatment of unstable Jefferson's fractures.

The Magerl transfacet screw technique is a method of fixation for unstable burst fractures of the atlas (Jefferson's fracture) that precludes the use of a halo brace or stabilization from the occiput to C2. Two cases are presented utilizing this mode of treatment to obtain solid arthrodesis and maintain intact motion at occipital cervical junction. No increased displacement of the fractured ring of C1 occurred with the screw insertion. Thus, primary C1-C2 transfacet screw fixation is a useful alternative treatment for unstable Jefferson's fractures.

Analysis of the torque applied to bone screws by trauma surgeons. Comparisons based on years of experience and material of implant construction.

Stability of an internal fixation construct is dependent on the torque placed on the screws holding the plate, the number of screws in the construct, and the number of cortices purchased by each screw. This study addresses the ability of surgeons to apply uniform torque and the variability between stainless steel and titanium. A total of 630 measurements were made by trained orthopedists using a device to measure the torque applied to 3.5 mm screws when tightening them to a plate. Variations were found to be significant depending on the number of years the orthopedist was in practice and the type of construct material used. The average torque applied to a stainless steel construct is 5.82 in-lb, while the torque applied to titanium is 5.41 in-lb (P < 0.01). The longer an orthopedist is in practice, the more torque will be applied to the screw/plate construct.

Comparison of anterior cervical fusions using autogenous bone graft obtained from the cervical vertebrae to the modified Smith-Robinson technique.

Anterior cervical discectomy and interbody grafting provide excellent results in treating cervical radiculopathy. This prospective study compares the results of the technique obtaining autogenous bone from the cervical vertebrae for grafting to the modified Smith-Robinson technique using autogenous iliac crest graft. Seven levels in six patients were fused using the vertebral body autograft technique and 43 levels in 40 patients using the standard technique. All patients had radiculopathy and neck pain. Statistically significant differences in fusion rate (4/7 vertebral body autograft; 40/43 modified Smith-Robinson) (p = 0.029), disc height maintenance (p = 0.001), and neck pain improvement (p = 0.05) occurred between the techniques. We do not recommend vertebral body autograft over the modified Smith-Robinson technique for anterior cervical fusion following discectomy.

Severe cervical kyphotic deformities in patients with plexiform neurofibromas: case report.

Two patients with cervical plexiform neurofibromas are presented. Each of these patients had severe cervical kyphosis and has undergone anterior decompression, anterior reconstruction, and posterior stabilization. We discuss the surgical management of cervical kyphotic deformities associated with plexiform neurofibromas and review the factors associated with bony changes in neurofibromatosis.

Pneumatic gouge versus standard method for iliac crest harvesting.

Fifty consecutive patients undergoing posterior lumbar fusion by a single surgeon were prospectively randomized in a study designed to evaluate the efficacy of using a pneumatic oscillating gouge to obtain posterior outer table iliac crest bone graft versus the standard method of using osteotomes and gouges. Variables analyzed included graft harvesting time, blood loss, weight of graft obtained, and graft site morbidity. Mean graft harvesting time with the pneumatic gouge was 1 minute 44 seconds (range, 1 min 5 sec to 3 min 15 sec) compared with the standard method time of 4 minutes 4 seconds (range, 2 min 15 sec to 8 min 56 sec) (P = 0.0001). Blood loss was also less, with a mean of 25.4 cc for the pneumatic gouge compared with 65.2 cc using the standard method (P = 0.0001). There were no complications with the graft site in either group. We conclude that the pneumatic gouge is a viable alternative to standard bone graft harvesting techniques. Benefits include shorter operative time and decreased blood loss without an increased morbidity.

The fate of autogenous bone graft in surgically treated pyogenic vertebral osteomyelitis.

A retrospective study of all surgically treated patients with pyogenic vertebral osteomyelitis grafted with autogenous bone for stability from 1980 to 1985 at the University of Miami and from 1985 to 1987 at Portsmouth Naval Hospital was performed. Eradication of infection occurred in all patients. Infection resolution occurred equally well in cases caused by gram-positive, gram-negative, and multiple organisms. In those patients requiring surgical treatment for pyogenic vertebral osteomyelitis, we found placement of autogenous bone graft at the time of primary debridement not to hinder eradication of infection. Arthrodesis occurred in 96% of the cases (26 of 27 patients).

Traumatic neuropathic arthropathy of the spine.

Traumatic neuropathic arthropathy of the spine is becoming more prevalent as a result of improvement in the medical care of patients with catastrophic neurological compromise. This case study discusses the etiology, pathophysiology, and treatment of this entity.

The use of primary internal fixation in spondylolisthesis.

A prospective randomized study was designed to examine differences in the primary fusion rate between two surgically treated groups of patients with spondylolisthesis. Twenty-seven patients underwent L5 laminectomy (Gill procedure) and L5 nerve root decompression. Fourteen patients (group I) underwent in-situ posterolateral fusion, thirteen patients (group II) received internal stabilization with the Steffee plate and screw system. All patients were followed for a minimum of two years. Ten of fourteen (72%) patients treated with non-instrumented fusion went on to union. Ten of thirteen (78%) patients treated with internal fixation achieved union. No statistically significant increase in the primary fusion rate occurred with addition of internal fixation compared to non-instrumented posterolateral grafting alone.

Degenerative cervical disc disease.

Degenerative cervical disc disease is a very common problem with most problems being resolved with conservative measures. Patients can present with a wide variation of complaints from neck pain to myelopathy secondary to spinal cord compression. In those patients requiring surgery for arm pain and myelopathy, the results are quite favorable.

Hemispheric processing strategies for lexical decisions among elderly persons.

Lexical decision vocal reaction times were obtained in 1990 for 30 young adult and 18 elderly subjects to tachistoscopically presented concrete and abstract words by Rastatter and McGuire. The young adults' data suggested differential right-hemispheric processing, while the elderly subjects' data were interpreted as suggesting that the right hemisphere loses its processing function. Here we reinterpret the elderly subjects' data based on visual information-processing theory and suggest that variations in processing strategy account more completely for their data.