Search PubMed⌕ Search

Biomedical subjects

J A Bouchard

Publications and source records attributed to J A Bouchard.

6 recordsLinked to original sources
PubMed2001

Osteoporotic spondylolisthesis: a case report.

STUDY DESIGN: A case of spondylolisthesis caused by osteoporosis is described. OBJECTIVES: To describe the different etiologies of spondylolisthesis, and to report a new cause of pathologic spondylolisthesis previously unreported in the literature. SUMMARY OF BACKGROUND DATA: The literature on the etiology of spondylolisthesis is reviewed. Pathologic spondylolisthesis has been described with structural abnormalities, such as Paget's disease and tumors, but not with osteoporosis. METHODS: A clinical and radiographic interpretation of the reported case is presented. RESULTS: De Novo development of a spondylolisthesis at L5-S1 occurred by gradual elongation of the pars interarticularis over a period of 3 years. CONCLUSION: The reported case adds to the literature on spondylolisthesis by describing another etiology for this conclusion. Osteoporotic spondylolisthesis may well be identified more frequently in the future given the high prevalence of osteoporosis in the elderly.

Aged↗
PubMed1999

[Not Available].

Explore the source record for details and available documents.

Journal Article↗
PubMed1996

Intraoperative improvements of somatosensory evoked potentials: correlation to clinical outcome in surgery for cervical spondylitic myelopathy.

STUDY DESIGN: Retrospective review of all patients who underwent surgical treatment of cervical spondylitic myelopathy and were monitored by somatosensory evoked potentials. OBJECTIVES: To identify the patients who had recognizable improvements in somatosensory evoked potential signals intraoperatively and to correlate the changes in somatosensory evoked potential signals to the post-operative clinical status of the patients and compare this group of patients with those that had stable intraoperative somatosensory evoked potential recordings. SUMMARY OF BACKGROUND DATA: Somatosensory evoked potentials are commonly used in the operating room to monitor potential injury to the spinal cord or alterations in spinal cord function. It may be possible to use intraoperative somatosensory evoked potentials to detect improvement in spinal cord function during the decompression of neural structures, as evidenced by an increase in amplitude or a decrease in the latency of the wave form. METHODS: Thirty-two patients with moderate to severe cervical spondylitic myelopathy requiring multi-level anterior decompression and fusion were monitored intraoperatively with somatosensory evoked potentials. The median and posterior tibial nerves were stimulated at the wrist and ankle, respectively. Somatosensory evoked potential recordings were obtained from cervical and scalp electrodes by the Nicolet Pathfinder electrodiagnostic system, preoperatively, intraoperatively, and postoperatively. RESULTS: Eleven of thirty-two patients demonstrated intraoperative improvement of somatosensory evoked potential signals after decompression. All patients had rapid recovery of motor strength, bladder control, and ambulatory capacity within days of surgery. The remaining twenty-one patients had stable somatosensory evoked potential recordings. Five had rapid resolution of their symptoms, 15 improved over the course of 6 to 8 weeks, and 1 did not improve. The motor recovery of this group at 8 weeks was equal to the group of patients that showed intraoperative improvements of evoked potential signals. CONCLUSIONS: 1) Multilevel anterior cervical decompression and fusion produced a significant improvement in the motor function of patients with cervical spondylitic myelopathy. 2) Patients with intraoperative increase in amplitude or shortening of latency had a more rapid clinical improvement than patients with stable recordings. 3) Long-term reassessment did not show any difference between patients with intraoperative somatosensory evoked potential improvement and those with stable somatosensory evoked potential recordings. Therefore, somatosensory evoked potential improvements cannot be used to determine prognosis at the present time. 4) A greater number of patients should be studied using more objective methods for quantifying gait patterns and motor function.

Aged↗
PubMed1996

Outcome of femoral shaft fractures in the elderly.

Published literature on fractures of the femoral shaft has reported results of treatment stratified by fracture type or treatment type. The current study analyzes the outcome of fractures of the femoral shaft in elderly patients. One hundred thirty-eight patients older than the age of 65 years sustained femoral shaft fractures. Ten percent of the patients had associated injuries. The majority of the patients had significant prefracture medical problems. Nonsurgical treatment was used in 29 cases. Surgical treatment in 109 patients consisted of cerclage wires in 13 cases, plates and screws in 58 cases, intramedullary nails in 26 cases, and long stem prostheses in 12 cases. Complications of treatment occurred in 46% of patients. The type of treatment did not influence the frequency of complications. Twenty percent of patients died within 6 months of the fracture. There was a significant difference in the age of the patients who survived compared with those who did not survive. The mental status of the patient was also a major determinant of survival. Alert and oriented patients had a much better chance of survival. The outcome of fractures of the femoral shafts cited in the literature is different from the results seen in this population of elderly patients. The observed complication rate of 46% and mortality rate of 20% in this series is similar to those reported for intertrochanteric fractures and femoral neck fractures. Age and mental status are important determinants in the survival of the patient regardless of the treatment administered.

Aged↗
PubMed1994

Effects of irradiation on posterior spinal fusions. A rabbit model.

STUDY DESIGN: The biological and biomechanical effects of irradiation on posterior bone graft healing in the lumbar spine of rabbits were investigated. Twenty-seven New Zealand white rabbits were divided into four groups. Each rabbit underwent a posterior lumbar spine fusion with autogenous iliac crest bone graft, and three of the experimental groups received perioperative irradiation. OBJECTIVES: This study evaluated the histologic and biomechanical effects of perioperative irradiation on posterior spinal fusions using a rabbit model. SUMMARY OF BACKGROUND DATA: Treatment of metastatic disease of the spine depends on the neurologic status of the patient, stability of the spine, location of the tumor, and the tissue of origin. Some patients require surgical decompression and stabilization. The response of a posterior spinal bone graft to irradiation has not been studied previously. METHODS: Group 1 (n = 7), the control group, did not receive irradiation. Group 2 (n = 6) received preoperative irradiation. Group 3 (n = 7) received immediate (day 3) postoperative irradiation, and Group 4 (n = 7) received delayed (day 21) postoperative irradiation. The radiation protocol consisted of 480 centigrade/fraction for 5 consecutive days. At 3 months, the rabbits were euthanatized. Nondestructive biomechanical testing was performed, followed by histologic evaluation of the fusion mass. RESULTS: Compared with the control group, Group 3 (immediate postoperative irradiation) specimens were less stiff in extension (P = .0001), flexion (P = .0006), compression (P = .018), and left lateral bending (P = .018). The preoperatively irradiated spines (Group 2) were less stiff in extension (P = .0008) and in compression (P = .035) than controls. The control group and the delayed irradiation group had the highest histologic scores and more mature fusion mass. The immediate postoperative irradiation group had the worst results, with consistent fibrous union of the graft. CONCLUSION: Healing of a posterior spinal fusion is influenced by the timing of radiation therapy. Adjuvant radiation therapy for patients with spinal neoplasm requiring a posterior fusion should, if possible, be delayed for 3 to 6 weeks postoperatively to maximize the probability of successful arthrodesis.

Animals↗