Postero-lateral spine fusion. A 1-4-year follow-up of 80 consecutive patients

We analysed 80 consecutive patients with postero-lateral spine fusion performed during the years 1972-1976. Thirty-seven were women and 43 men, the mean age being 30 (14-54) years. In 73 cases the fusion was performed because of spondylolysis and spondylolisthesis and in seven because of some other form of painful instability. Preoperatively, all patients had pain in normal activities and 63 at rest. At the 1-5-year follow-up, eight patients were pain-free, while 69 had stress pain and 35 pain at rest. The reduction of pain was significant; 51 patients considered themselves improved, 18 unchanged and 10 worse. Twelve fusions united in less than 2 months, eight after more than 4 months, and two failed to unite. Patients under 20 years did better than older patients. The result was better when the fusion united within 4 months and also when the bone transplants were properly placed. We conclude that postero-lateral spine fusion can be advocated as treatment of painful spondylolisthesis and sometimes in low-back instability in younger patients.