Fifty-three children who were less than thirteen years old were followed for a median of seven years and ten months (range, two years and nine months to fourteen years and six months) after operative treatment for overgrowth of the tibia or humerus after amputation. During the thirty-one years in which these children were managed, three operative techniques were used in successive periods. Thus, the fifty-three children could be divided into three groups: thirty-one who had had a resection and revision, nine in whom the bone had been capped with a synthetic device, and thirteen in whom the bone had been capped with an autogenous tricortical bone graft from the iliac crest. A retrospective review was performed to determine the result and complications associated with each of these techniques. Survival analysis revealed that subsequent procedures were performed in twenty-six (84 per cent) of the thirty-one patients who had had a resection and revision, in seven of the nine in whom the bone had been capped with a synthetic device, and in four of the thirteen in whom the bone had been capped with an autogenous bone graft. The estimated mean survival time (that is, the time to a subsequent procedure) was five years in the group that had had the bone capped with an autogenous graft and three years and six months in the group that had had resection and revision; the difference is significant (p = 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)