Early Radiological Analysis of Cervical Arthroplasty with Bryan and Mobi-C Cervical Disc Prosthesis

OBJECTIVE: We investigated whether there are any different results in the overall sagittal alignment, neutral functional spine unit (FSU) angle and segmental FSU ROM (range of motion) angle from the patients undergone by cervical arthroplasty with two kinds of artificial cervical disc prostheses, Bryan and Mobi-C cervical disc. METHODS: Twenty eight patients underwent anterior cervical discectomy and implantation of artificial cervical disc prosthesis; Eighteen of them underwent operation with Bryan and the rest of them with Mobi-C cervical disc prosthesis. These patients consist of fourteen females and fourteen males with mean age 46.9 years old and 9.4 months mean follow-up period. There were 4 cases of C 4-5, 18 cases of C 5-6 and 6 cases of C 6-7 level. We measured overall sagittal alignment, neutral FSU angle and segmental FSU ROM angle using lateral radiographs preoperatively and postoperatively. The clinical outcome was evaluated by neck disability index(NDI). RESULT: The average angle of overall sagittal alignments was changed from -17.45degrees preoperatively to -14.21degrees postoperatively in Bryan cervical disc group. It decreased 3.24degrees in cervical lordosis. However, in Mobi-C cervical disc group, the average angle of overall sagittal alignments was changed from -10.33degrees preoperatively to -16.89degrees postoperatively. It increased 6.56degrees in cervical lordosis. The averages of neutral FSU angles were -1.14degrees preoperatively and -3.26degrees postoperatively in Bryan cervical disc group, and were -0.93degrees preoperatively and -9.7degrees postoperatively in Mobi-C cervical disc group. The averages of segmental FSU ROM angles were 11.18degrees preoperatively and 10.61degrees postoperatively in Bryan cervical disc group, and was 8.31degrees preoperatively and 13.6degrees postoperatively in Mobi-C cervical disc group. NDIs were 24.0 preoperatively and 5.9 postoperatively in Bryan cervical disc group, and 24.7 preoperatively and 8.7 postoperatively in Mobi-C cervical disc group. CONCLUSION: Postoperative cervical lordosis and segmental FSU ROM angle were increased in Mobi-C cervical disc group (p<0.05). To preserve segmental motion and avoid adjacent segment degeneration is to the focus in cervical arthroplasty. To preserve cervical lordosis after operation is physiologic than postoperative cervical kyphosis. It remains controversial whether cervical kyphosis influences clinical outcome after anterior cervical operation. The results of this study show that the technical and mechanical improvement of Bryan cervical disc prosthesis may be considered.

A Clinical Analysis of Treatment of Acute Cervical Spinal Injury

A retrospective study of 100 cervical spinal cord injury patients admitted consequtively to the Department of Neurosurgery, Dongsan Medical Center, Keimyung University between March, 1985 and June, 1989 was conducted. The average age was 42 and 84(84%) were male. The majority sustained their spinal cord injury in a motor vehicle accident(50%) or in a diving accident(36%). Thirty-three percent(33/100) of these patients had surgical intervention by anterior approach(14/33), posterior approach(17/33) and total laminectomy(2/33). The others were only immobilized by traction or neck brace. Not only neurological recovery in operated and nonoperated patients but also complete and incomplete injury was compared. The degree of the neurological injury was classified by the Frankel classification. 12 cases turned out to be more aggravated than the condition at admission, among them 9 cases were middle and low cervical incomplete injuries. At final follow-up no appreciable differences in achievement in activities of daily living and mobility were noted between patients treated with surgical stabilization of the cervical spinal column and those treated nonsurgically.

Hematocrit, Blood Viscosity and Plasma Viscosity in Patients with Aneurysmal Subarachnoid Hemorrhage

In order to find out the relationship between blood viscosity and the development of an ischemic symptom(clinical vasospasm) following an aneurysmal subarachnoid hemorrhage(SAH), was checked daily the hematocrit(Hct), blood viscosity and plasma viscosity from admission day to 14 days after SAH in 33 patients. Twelve patients with diseases except those with a SAH were selected as a control group. We analyzed the difference of the average hematocrit, blood viscosity, and plasma viscosity between the control group, non-spasm group and spasm group on admission, and then the period of preoperative, postoperative with mannitolization, and postoperative without mannitolization. We also analyzed the change of those according to the SAH day, and the relationship between the blood viscosity and the level of hematocrit in each group. As a result, aneurysmal SAH patients with clinical vasospasm showed a higher plasma viscosity than the control(1.82+/-0.21 vs. 1.55+/-0.14, respectively : p<0.01) and clinical non-spasm(1.82+/-0.21 vs. 1.66+/-0.12, respectively : p<0.05) group of patients on admission statistically. In the spasm group, the blood viscosity was raised during the spasm risk period(SAH 7-10 days). The level of the hematocrit in the spasm group was lower than the non-spasm group and most of them checked below 30% after surgery. In the relationship between the level of hematocrit and the blood viscosity, the spasm group showed a relatively higher blood viscosity than the non-spasm group. These results suggest that the blood viscosity has some role in the development of ischemic symptoms after a subarachnoid hemorrhage, but major determinants such as erythrocyte aggregation, plasma fibrinogen concentration and platelet aggregation which affect the microcirculation have a more important role. Therefore, when hemodilution are used for prevention or improvement of ischemic symptoms after subarachnoid hemorrhage, the level of the hematocrit and the focus on decreasing the major determinants of the viscosity in microcirculation should be considered.

Surgical Treatment of Spontaneous and Traumatic Delayed Cerebrospinal Fluid(CSF) Rhinorrhea

The authors presented 9 cases of surgically treated CSF rhinorrhea, two of which were spontaneous and 7 were traumatic delayed. The duration of leakage was longer than 1 month in most cases and seven of the nine cases were complicated by meningitis. The leakage site was most accurately detected by metrizamide computed tomographic cisternography(MCTC) and the most frequent leakage site was the cribriform plate. Good surgical results were obtained by direct repair and/or shunt without recurrence during follow-up period from 7 months to 2 years.