Posterior intervertebral body fusion. A 25-year study.

The benefits derived from intervertebral body fusion using a posterior surgical approach were studied in 500 patients. The cases were reviewed during a 25-year period, with an average follow-up period of more than five years. Only eight patients did not return for adequate postoperative evaluation. Seventy-five percent of patients underwent primary excision of the disc with fusion, 11% had spondylolisthesis defects, and in 19% a second operation was performed after prior excision of the disc had failed. Discography provided the most reliable diagnostic procedure after physical examination. Disc degeneration and protrusion occurred 1 1/2 times more often in the fourth than in the fifth disc. Fusion occurred in 90% of patients. Eighty-two percent of patients rated the end result as excellent or good. Two blocks of autogenous bone from the ilium were used in all cases to produce the fusion. The surgical procedure and the complications that occurred are described.