Functional and clinical results after anterior interbody lumbar fusion.

The functional and clinical results of anterior interbody lumbar fusion were assessed in 134 patients. Functional tests included spinal mobility and isokinetic trunk muscle strength measurements. The score rating system of the Japanese Orthopaedic association (JOA) and the Oswestry disability index were used for clinical evaluation. Functional results revealed decreased spinal flexibility when compared with normal values. A reduction in physical ability was also seen in the isokinetic trunk muscle measurements. Non-union seemed to have only little effect on the functional results. Patients under 20 years at operation had the best results, but beyond this threshold results did not vary with age. The JOA rating score was 25 or more in 50% of patients. The mean Oswestry disability index was 47.8 (range 1-82) preoperatively and 20 (range 0-68) at follow-up (P < 0.001), indicating a clear decrease in subjective disability. Solid fusion was seen in 107 patients (80%) at follow-up.