The authors evaluated the long-term clinical outcome of a total posterior arthroplasty system in the surgical treatment of lumbar spinal stenosis with degenerative spondylolisthesis.
Between June 2006 and July 2007, 10 patients with neurogenic claudication due to spinal stenosis and single-level degenerative spondylolisthesis were enrolled in a nonrandomized prospective clinical study. The patients were evaluated with radiographs and MRI scans, the visual analog scale (VAS) for back and leg pain, the Oswestry Disability Index (ODI), and the SF-36 health survey preoperatively and at 6 weeks, 3 months, 6 months, 1 year, 2 years, 3 years, 7 years, and 11 years postoperatively.
The mean VAS score for leg pain dropped from 83.5 before surgery to 13 at 6 weeks and 17 at 11 years after surgery. The mean VAS score for back pain dropped from 56.2 preoperatively to 12.5 at 6 weeks and 14 at 11 years after surgery. The mean ODI score decreased from 49.1 preoperatively to 13.5 at 6 weeks and 16 at 11 years after surgery. MRI at 11 years demonstrated stenosis adjacent to the stabilized segment in one patient. This patient was not symptomatic. The authors did not find evidence of progression of the spondylolisthesis in any of the cases. In one patient, conversion to posterolateral fusion was performed due to an early device malfunction.
The results of this 11-year follow-up study demonstrate that, in patients with spinal stenosis and degenerative spondylolisthesis, decompression and posterior arthroplasty maintain clinical improvement and radiological stability.