Two hundred and seventeen patients who had sustained an injury during the recreational use of a trampoline were managed in the emergency room of Logan Regional Hospital in Logan, Utah, from January 1991 through December 1992. We retrospectively reviewed the charts and radiographs of these patients to categorize the injuries. Additional details regarding the injuries of seventy-two patients (33 per cent) were obtained by means of a telephone interview with use of a questionnaire. The injuries occurred from February through November, with the peak incidence in July. The patients were eighteen months to forty-five years old (average, ten years old); ninety-four patients (43 per cent) were five to nine years old. Eighty-four patients (39 per cent) sustained a fracture; fifty-four (25 per cent), a sprain or strain; forty-five (21 per cent), a laceration; and thirty-four (16 per cent), a contusion. Fifty-seven injuries (26 per cent) involved the elbow or forearm; forty-six (21 per cent), the head or neck; forty (18 per cent), the ankle or foot; thirty-three (15 per cent), the knee or leg; nineteen (9 per cent), the trunk or back; thirteen (6 per cent), the shoulder or arm; and nine (4 per cent), the wrist or hand. Thirteen patients (6 per cent) had a back injury, but none of them had a permanent neurological deficit. One patient who had an ocular injury was transferred to a tertiary care center. One hundred and fifty-six patients (72 per cent) were evaluated radiographically, fifteen (7 per cent) were admitted to the hospital, and thirteen (6 per cent) had an operation.(ABSTRACT TRUNCATED AT 250 WORDS)