One hundred twelve cases of blunt splenic rupture were prospectively entered (October 1987-October 1991) into surgical or nonsurgical management groups using these criteria for the nonsurgical group: hemodynamic stability+age less than 55 years+CT scan appearance of grade I, II, or III injury+absence of concomitant injuries precluding abdominal assessment+absence of other documented abdominal injuries. All ages were included and AAST injury scaling was used. Patients were grouped from the trauma room. The surgical treatment group included 66 patients (49 splenectomies, 17 splenorraphies). These patients were generally older and more severely injured, required more transfused blood, and a longer ICU stay. The nonsurgical group included 46 patients with 33 older than 14 years. There were 3 patients over the age of 55 years inappropriately included in this group, and nonsurgical therapy failed in all three. Statistical analysis (chi 2) showed that more splenic injuries were observed and more spleens were saved with these criteria applied prospectively compared with a previous retrospective series in the same institution. Our series had a success rate of 93%, and validates the criteria used for safe, nonsurgical management of the ruptured spleen and adds a new criterion: a maximum age of 55 years.