This SPORT subanalysis asks whether extending fusion beyond the spondylolisthesis level improves outcomes in patients with single-level degenerative spondylolisthesis and multilevel lumbar stenosis. 207 surgical patients were compared: 130 received multilevel decompression with single-level fusion, and 77 received multilevel decompression with multilevel fusion. All primary and secondary outcomes were tracked through 4 years.
When you see a patient with single-level degenerative spondylolisthesis and stenosis at two or three levels, the instinct to fuse everything is understandable — but this data does not support it.
At 4 years, every outcome measure (pain, function, disability, satisfaction) was statistically equivalent whether you fused one level or multiple levels. The only differences were operative time (63 minutes longer) and blood loss (161 mL more) in the multilevel group, with no corresponding patient benefit.
This matters especially in the elderly, comorbid patients who typically present with this pathology. Added operative time and blood loss carry real risk in patients with hypertension, cardiac disease, and osteoporosis — all common in this cohort.
The pseudarthrosis finding adds a practical nuance: single-level fusion had a 2.4% pseudarthrosis rate vs. 0% in multilevel fusion, but this was driven by higher rates of non-instrumented fusion in the single-level group, not by the number of levels fused. Use instrumentation at the spondylolisthesis level regardless of how many levels you fuse.
The study's 4-year horizon is its main limitation. Adjacent segment disease from decompression without fusion above a rigid construct may take longer than 4 years to declare itself clinically.
This SPORT subanalysis asks whether extending fusion beyond the spondylolisthesis level improves outcomes in patients with single-level degenerative spondylolisthesis and multilevel lumbar stenosis. 207 surgical patients were compared: 130 received multilevel decompression with single-level fusion, and 77 received multilevel decompression with multilevel fusion. All primary and secondary outcomes were tracked through 4 years.
When you see a patient with single-level degenerative spondylolisthesis and stenosis at two or three levels, the instinct to fuse everything is understandable — but this data does not support it.
At 4 years, every outcome measure (pain, function, disability, satisfaction) was statistically equivalent whether you fused one level or multiple levels. The only differences were operative time (63 minutes longer) and blood loss (161 mL more) in the multilevel group, with no corresponding patient benefit.
This matters especially in the elderly, comorbid patients who typically present with this pathology. Added operative time and blood loss carry real risk in patients with hypertension, cardiac disease, and osteoporosis — all common in this cohort.
The pseudarthrosis finding adds a practical nuance: single-level fusion had a 2.4% pseudarthrosis rate vs. 0% in multilevel fusion, but this was driven by higher rates of non-instrumented fusion in the single-level group, not by the number of levels fused. Use instrumentation at the spondylolisthesis level regardless of how many levels you fuse.
The study's 4-year horizon is its main limitation. Adjacent segment disease from decompression without fusion above a rigid construct may take longer than 4 years to declare itself clinically.