Acquired spondylolisthesis following scoliosis surgery. A case report.

The association between scoliosis and spondylolisthesis is well documented; however, spondylolisthesis following a posterior spinal fusion with Harrington rod instrumentation for idiopathic scoliosis has not been previously reported. Internal fixation of the spine with metal rods and fusion for scoliosis produces a stress concentration at the immediately adjacent levels. This, combined with other factors that may cause failure of the neural arch, can lead to a traumatic spondylolisthesis. In an 11-year-old boy, localized pain and impending listhesis indicated that the instrumentation should be removed and an arthrodesis completed.