The SPORT degenerative spondylolisthesis trial enrolled 607 patients across 13 U.S. centers into parallel randomized and observational cohorts. It compared standard decompressive laminectomy (with or without fusion) against nonsurgical usual care in patients with imaging-confirmed degenerative spondylolisthesis and at least 12 weeks of symptoms. Primary outcomes were SF-36 bodily pain, physical function, and the Oswestry Disability Index at up to 2 years.
When you see a patient over 65 with neurogenic claudication, imaging-confirmed degenerative spondylolisthesis, and symptoms lasting more than 3 months despite conservative care, this paper is the evidence base for offering surgery.
The key number to remember: surgery produced an 18-point SF-36 improvement over nonsurgical treatment at 2 years. That is a large, clinically meaningful effect that persisted across both the randomized and observational cohorts — not a statistical artifact.
Be cautious interpreting the intention-to-treat result (no significant difference). It does not mean surgery and nonsurgical care are equivalent. It means that when 40% of patients cross over in each direction, RCT methodology breaks down for this disease. The as-treated analysis with careful covariate adjustment is the interpretable result.
One practical nuance: unlike disk herniation, spondylolisthesis does not get better on its own. Nonsurgical patients improved only modestly, which means the window for spontaneous recovery that justifies prolonged watchful waiting in herniation patients does not apply here.
The SPORT degenerative spondylolisthesis trial enrolled 607 patients across 13 U.S. centers into parallel randomized and observational cohorts. It compared standard decompressive laminectomy (with or without fusion) against nonsurgical usual care in patients with imaging-confirmed degenerative spondylolisthesis and at least 12 weeks of symptoms. Primary outcomes were SF-36 bodily pain, physical function, and the Oswestry Disability Index at up to 2 years.
When you see a patient over 65 with neurogenic claudication, imaging-confirmed degenerative spondylolisthesis, and symptoms lasting more than 3 months despite conservative care, this paper is the evidence base for offering surgery.
The key number to remember: surgery produced an 18-point SF-36 improvement over nonsurgical treatment at 2 years. That is a large, clinically meaningful effect that persisted across both the randomized and observational cohorts — not a statistical artifact.
Be cautious interpreting the intention-to-treat result (no significant difference). It does not mean surgery and nonsurgical care are equivalent. It means that when 40% of patients cross over in each direction, RCT methodology breaks down for this disease. The as-treated analysis with careful covariate adjustment is the interpretable result.
One practical nuance: unlike disk herniation, spondylolisthesis does not get better on its own. Nonsurgical patients improved only modestly, which means the window for spontaneous recovery that justifies prolonged watchful waiting in herniation patients does not apply here.