Purpose: To evaluate the feasibility and clinical improvement of a total posterior arthroplasty system in the surgical management of lumbar degenerative spondylolisthesis and or spinal stenosis.
Methods: During a 1-year period (June 2006 to July 2007), ten patients were enrolled in a non-randomized prospective clinical study. The primary indication was neurogenic claudication due to spinal stenosis with single-level degenerative spondylolisthesis. Patients were evaluated with X-rays and MRI scans, visual analog scale (VAS) for back and leg pain, the Oswestry disability questionnaire, and the SF-36 health survey preoperatively, at 6 weeks, 3 months and 6 months and at 1, 2, 3 and 7 years postoperatively.
Results: The VAS score for back pain dropped from 56.2 preoperatively to 12.5 at 6 weeks and 19 at 7 years follow-up. The VAS score for worse leg pain dropped from 83.5 before surgery to 13 at 6 weeks and 8.8 at 7 years follow-up. The ODI dropped from 49.1 preoperatively to 13.5 at 6 weeks and 7.8 at 7 years follow-up. MRI examination at 7 years after surgery did not demonstrate stenosis adjacent to the stabilized segment. Spondylolisthesis did not progress in any of the cases. One patient had a symptomatic L3-L4 far lateral disc herniation 5 years after surgery whose symptoms resolved with non-operative treatment. In one patient, conversion to posterolateral fusion was performed due to an early device malfunction.
Conclusion: In patients with spinal stenosis and degenerative spondylolisthesis, decompression and posterior arthroplasty with the TOPS System can maintain clinical improvement and radiologic stability over time.
Keywords: Degenerative spondylolisthesis; Neurogenic claudication; Spinal stenosis; TOPS.