Lumbar Spinal Fusion plus Laminectomy is Superior to Laminectomy alone for Grade I Degenerative Spondylolisthesis: SLIP Study ResultsZoher Ghogawala, MD1, Edward C. Benzel, MD1, William Butler, MD1, James Dziura1, Subu N. Magge, MD1, Jean-Valery C. E. Coumans, MD1, J. Frederick Harrington Jr., MD1, Volker K. H. Sonntag, MD1, Frederick G. Barker II, MD11Greenwich, CT United States Keywords: randomized trial, spondylolisthesis, spinal fusion, laminectomy, pain
The value of fusion after laminectomy in patients with spondylolisthesis varies.
To compare quality of life outcome following laminectomy with fusion to laminectomy alone for lumbar spinal stenosis with grade I spondylolisthesis.
A prospective, 5-center RCT was conducted from 2002-2009. Patients aged 50-80 with degenerative spondylolisthesis (3-14 mm) with symptomatic lumbar spinal stenosis were eligible. Patients with mechanical instability or gross motion (< 3mm) were excluded.
Patients were randomized to receive either laminectomy alone or laminectomy with posterolateral instrumented fusion. Primary outcome measure (SF-36 PCS) was assessed in the clinic at 1, 3, 6, and 12 months, and then annually for 5 years by phone. Sample size estimate to demonstrate superiority with 80% power was 64 patients.
130 patients were screened, 106 were enrolled, and 66 randomized to receive either decompression alone versus decompression with fusion. Mean age was 66.7 years (80.3% female). Follow-up rate was 86% (2 years) and 85% (4 years). Surgery was associated with significant improvement in SF-36 PCS and ODI scores at each time point (P<0.05). Laminectomy with fusion had significantly better SF-36 PCS (primary outcome measure) scores than laminectomy alone at 6 months (P=0.03), 2 years (P=0.02), and at 4 years (P=0.01) post-operatively. For patients treated without fusion, re-operation rate was 12/34 (35.3%). When fusion was added to laminectomy, re-operation rate was considerably lower: 4/31 (12.9%) (P=0.036).
This was a prospective study. Quality of life was evaluated via SF-36.
Lumbar spinal fusion added to laminectomy when treating degenerative grade I spondylolisthesis is associated with superior SF-36 PCS outcome.
Fusion led to fewer re-operations within 4 years of the initial procedure. Project Roles:
Z. Ghogawala (), E. Benzel (), W. Butler (), J. Dziura (), S. Magge (), J. E. Coumans (), J. Harrington Jr. (), V. H. Sonntag (), F. Barker II ()