Decompression and distraction-derotation arthrodesis for degenerative spondylolisthesis.

Degenerative spondylolisthesis is the result of chronic disc degeneration with secondary segmental spinal instability. Localized collapse and translational and rotational vertebral subluxation result in low back pain and radiculopathy. Twenty patients with L4-5 degenerative spondylolisthesis having back pain and radiculopathy were treated with a combination of decompressive laminectomy and distraction arthrodesis with short parallel Harrington rods. Patients were ambulated immediately after operation. Minimum follow-up was 2 years (average, 31.6 months). Satisfactory results were obtained in 17 patients (85%). No intraoperative complications occurred. The spondylolisthesis progressed significantly in one patient and the Harrington rods loosened in another. The procedure appears to assist in reducing pathologic motion contributing to low back pain and to relieve traction or compression forces on neural structures by restoring spinal canal anatomy.