Clinical and Radiological Outcomes with the Lumbar Total Disc Replacements

OBJECTIVE: To determine the clinical and radiographic results and incidence of complications in lumbar arthroplasty patients. METHODS: From January, 2003 to March, 2005, 46 patients were implanted with 30 cases of the Charite Artificial Disc and 16 cases of the Prodisc. There were 28 males and 18 females with a mean age 40.6 years(range, 21~70). Diagnoses included 19 patients with discogenic back pain, and 27 patients with FBSS. All patients were examined at a minimum 2-year follow-up(mean 3.5 years). Clinical outcomes were assessed by Oswestry Disability lndex(ODI), Visual Analogue Scale(VAS),and Macnab's Criteria. Dynamic lateral flexion and extension radiographs were used to radiologic assessment. RESULTS: The ODI was reduced from 67.6% to 8.9% at the latest follow up. The mean VAS baseline was 8.29 and 2.08 at the latest follow-up. Clinical outcome was excellent or good in 40 patients(mean 87, 93% FBSS, 78% Discogenic back pain). Mean flexion/ extesion range of motion at L4-5 was 9.1degrees Charite, 9.8degrees Prodisc and at L5-S1 it were 5.5degrees, 5degrees. A total of 7 complications(15%) were noted [subsidence (2), polyethylene core wire break down (1), vertebral body posterior inferior cortex breakage (1), anhydrosis (2), nerve root damage (1)]. CONCLUSIONS: This study demonstrates the safety and efficacy of the total disc replacements especially FBSS cases.

Posterior Interbody Fusion with TFC in Degenerative Lumbar Diseases

Surgical treatment for chronic back pain in degenerative lumbar spine has been still complicated. Several kinds of devices for spine fusions have been developed, but they have had both some advantages and disadvantages. Recently, the TFC(Threaded fusion cage) instrument has been introduced in treating lumbar spinal disorders associated with degenerative changes. The authors analysed 15 cases of lumbar degenerative disease treated with adequate decompression and TFC instrumentation between October 1993 and March 1994 at Ewha Womans University Mokdong Hospital. There were 10 females and 5 males. The main surgical indication was serious limitation of daily activity, which was not treated conservatively. The preoperative diagnoses were 6 degenerative stenosis with disc, 6 degenerative spondylolisthesis, 2 spondylosis and spondylolytic spondylolisthests, and 1 FBSS. We observed that 93% of patients(14 of 15) had more than good results and preoperative back pain was markedly reduced. Intervertebral disc space was well restored, and the reduction was possible in spondylolisthesis patients. In our opinion, TFC instrument will be one of good surgical modality in the treatment of degenerative lumbar spine.

Clinical Evaluation of Failed Back Surgery Syndrome(FBSS)

The authors experienced 186 cases of Failed Back Surgery Syndrome(FBSS), which were 2.5% of all admitted patients in authors' clinic from 1983 to 1992. Among them, 173 patients were referred cases from other hospital and 13 patients were authors' cases which was 0.2% of authors' back surgery. About 75% of all was come to our clinic within 2 years after initial operation. The common cause of FBSS was resulted form inadequate surgery or surgical complications (51%). In these cases, incomplete decompression at initial operation was seemed to be a major factor. The next causes was due to inadequate patient selection(26.3%) and the FBSS was more prevalent when the patient had only back pain without leg pain. The other causes of FBSS was post-operative adhesion(8.6%), discitis(4.3%), and inadequate diagnosis(4.3%). So about 80% of FBSS seem to have preventable causes. 66 of 186 cases was performed reoperation and 70% of them had improvement.