BACKGROUND: Recent reports note a dramatic increase in the number of pediatric trampoline injuries (PTI) during the past several years. In 1996, the US Consumer Product Safety Commission estimates that 83 000 patients received treatment for trampoline injuries in US hospital emergency departments (EDs), and that approximately 75% of these patients were <15 years of age. We sought to review our experience with PTI since our previous report (Pediatrics 1992;89:849), and to determine if the American Academy of Pediatrics' current (Pediatrics 1981;67:438) safety recommendations are adequate. METHODS: Retrospective medical record review of all PTI patients presenting to the pediatric ED from November 1990 through November 1997. RESULTS: A total of 727 PTI patients were included; medical records were unavailable for 3 patients. The annual number of PTI nearly tripled during the study period, from 51 in 1991 to a peak of 148 in 1996. PTI patients were 53% female, with a median age of 7 years; 37% were <6 years of age. Privately owned trampolines accounted for 99% of PTI. Most injuries (66%) occurred on the trampoline, 28% resulted from falls off, and 4% from imaginative mechanisms. One hundred eleven patients (15%) suffered severe injury (1990 Abbreviated Injury Scale value >/=3), usually of an extremity (89 out of 111). Fractures occurred in 324 patients (45%). Spinal injuries were common (12%), including 7 patients with cervical or thoracic fractures, and 1 with C7 paraplegia. Fractures were more frequently associated with falls off the trampoline, whereas spinal injuries more frequently occurred on the trampoline. Eighty patients (11%) required prehospital medical transport to our ED, 584 (80%) had ED radiographs, and 382 (53%) required pediatric surgical subspecialty involvement. Seventeen percent of PTI patients (125 out of 727) were admitted to the hospital, including 9 to the pediatric intensive care unit; 99 (14%) required one or more operations. Mean hospital stay was 2 days (range, 1-63 days); 24 stays (19%) were for >/=3 days. We estimate that the hospital charges for the acute medical care of PTI study patients at our institution totaled approximately $700 000. CONCLUSIONS: PTI are dramatically increasing in number, and result in considerable childhood morbidity. Most PTI occur on privately owned trampolines. Few, if any, safety recommendations for the trampoline are followed. We support recommendations for a ban on the recreational, school, and competitive pediatric use of trampolines.