Rethinking Surgical Treatment of Lumbar Spondylolisthesis: Anatomic Considerations.

The goal was to develop a classification of degenerative spondylolisthesis (DS) and concurrent lumbar spinal stenosis (LSS) based on pathologic stage and determine how these subtypes of DS affect outcomes for minimally invasive decompression. Patients who underwent microendoscopic laminotomy for single-level LSS with DS were included. Degenerative spondylolisthesis pathologic staging was defined as early, advanced, or end stage, based on percent slippage (10% slippage), degree of dynamic instability (3 mm), and disc height. Less than 10% required additional surgery; 5% required subsequent fusion, and all these patients were in the advanced stage DS group.