Review of seventy-three cases of spondylolisthesis treated by arthrodesis

• The finding of spondylolisthesis was accompanied by the complaint of backache with or without lower extremity pain in 72 of 73 patients; in the remaining case the symptom was that of unilateral sciatica. In 35 cases no history of trauma could be elicited. In five cases the fifth lumbar vertebra had slipped forward more than half the distance across the superior surface of the sacrum. The basic treatment in all 73 cases was an arthrodesis; in addition, protruding disks required excision in three cases. Sixty patients were restudied 3 to 19 years after the operation. The desired solid ankylosis had been achieved in only 24 patients. The pseudarthroses found in the other 36 were more frequent in the patients receiving bone grafts from a bone bank instead of iliac grafts, or confined to bed for only four weeks or less. Significant pain persisting in the legs after operation was explained by the finding of pseudarthrosis in 6 out of the 10 patients whose results were classified as fair or poor, but moderate pain continued also in 3 patients in whom solid fusion was achieved. It is recommended that further efforts be made to improve the technique of arthrodesis in this situation, that use of a bilateral spica cast to the knees be continued for three months after operation, and that early ambulation be avoided. The success of the operation should be verified by suitable roentgenograms, and a program of exercise and training should begin as soon as the patient becomes ambulatory.