The purpose of this study was to prospectivly evaluate the outcome of a decompressive procedure for degenerative spondylolisthesis without fusion designed to preserve facet joints. The “Semi circumferential decompression” technique that allows resecting the yellow ligament “en bloc” through the operating microscope and fine air drills (1.5-2mm).
Eighty two concecutive patients were studied prospectively between Feb 1992 and Feb 1997. The average age of the patients was 67.6 years (range 49-85). Range of follow up was 12 months-62 months (mean 28 months). The overall clinical results were graded by JOA score as good to excellent (70%) fair (13%) and poor (17%). Four cases required reoperation. The surgical procedure decompression without fusion is not widely accepted at the moment, if the posterior structure was not violated with meticulous decompression technique under surgical microscope making spinal fusion rarely required.