Replacement laminoplasty in selective dorsal rhizotomy: possible protection against the development of musculoskeletal pain.

The authors present a retrospective review of 35 patients who underwent selective dorsal rhizotomy between 1990 and 1992. The first 15 patients underwent laminectomy from L1 to the sacrum without replacement of the posterior elements. The subsequent 20 patients had the laminae replaced during wound closure. No patient in either group developed spinal instability or symptomatic deformity. However, 4 patients in the first group (mean follow-up period 35 months) developed significant low-back pain of musculoskeletal origin following minor accidents (mean time to injury 12 months). No patients in the group in whom the laminae were replaced (mean follow-up period 24 months) developed back pain. This review suggests that although the lumbar laminae are not essential for the structural integrity of the spine, their removal may predispose to musculoskeletal injury and associated pain. The authors propose a mechanism for these findings and recommend replacement of the posterior elements when possible.