Randomized trials of lumbar fusion in addition to laminectomy for lumbar stenosis.
Two randomized controlled studies were recently published that challenge the notion that instrumented fusion as an adjuvant to surgical decompression improves outcome when treating lumbar spinal stenosis. Forsth et al. randomized patients with symptomatic one and two-level lumbar stenosis with and without grade 1 spondylolisthesis into groups for laminectomy-only (N=124, 68 with spondylolisthesis) and laminectomy with instrumented fusion (N=123, 67 with spondylolisthesis). The fusion group did not perform better in any outcome measure (including the Oswestry Disability Index) compared to the decompression-only group (including the spondylolisthesis subgroups). Ghogawala et al. randomized patients with single-level stable degenerative spondylolisthesis and symptomatic lumbar stenosis into laminectomy-only (N=35) and laminectomy with fusion (N=31) groups. The fusion group had clinically significant increased improvement on the SF-36 physical-component summary and a lower reoperation rate compared to the decompression-only group but improvement in ODI scores was comparable between groups. Based on these studies, we can conclude that there is at most a modest benefit to performing a fusion in a patient with lumbar stenosis with grade I spondylolisthesis that should be weighed carefully against the significant added cost of fusion.