Objective To investigate the long-term clinical results of treatment of adult unicameral bone cyst with cancellous allograft. Methods From 1993 to 1998, 15 patients with unicameral bone cyst were treated by allograft with lyophilized cancellous bone. Among 15 patients, there were 5 males and 10 females, aging 19-41 years with an average of 27 years. The average follow-up time was 7.5 years (6-11 years). The X-ray films were taken and the CT scanning were carried out. Results The X-ray films showed that the allograft particles became vague 2-3 months after operation, that the allograft particles fused and began to form new bone and the bone density increased 5 months after operation, and that new bone formation completed after 7 months of operation. At the end of follow-up, remodelling in new bone occurred. Reoccurrence was not found in all patients. The symptom of pain disappeared or relieved obviously. Conclusion Allograft of lyophilized cancellous bone is an effective treatment for adult unicameral bone cysts.
