More on Fusion Surgery for Lumbar Spinal Stenosis

To the Editor: The replies to the letters to the editor (Aug. 11 issue) 1 , 2 about our article on the Swedish Spinal Stenosis Study (SSSS) 3 and the article by Ghogawala et al. on the Spinal Laminectomy versus Instrumented Pedicle Screw (SLIP) trial 4 describe the use of additional fusion surgery in patients who undergo surgery for lumbar spinal stenosis with degenerative spondylolisthesis. We want to comment on the misinterpretation in the reply by Ghogawala et al. that “neither trial was appropriately powered to detect a between-group difference” in the Oswestry Disability Index (ODI; scores range from 0 to 100, with higher . . .