Nonoperative management (NOM) of blunt splenic injury has become more frequent in the past several decades. Criteria that predict successful NOM remain poorly defined, and one factor that has been studied previously has been patient age. Previous studies have defined older patients as those greater than 55 years of age, but no studies have compared younger patients (55-75 years) with older patients (75+ years) within this age group. A total of 1008 patients > or =55 years of age who sustained blunt splenic injury between 1993 and 2001 were analyzed from the Pennsylvania Trauma Systems Foundation database. Statistical analysis was performed using regression analysis. Data was expressed as mean +/- SD, and a P value of < or = 0.05 was considered significant. Patients were classified as operative management (OM; 39.9%) or NOM (60.1%) according to their initial plan of treatment. Of the patients in the NOM group, 75.3 per cent were successfully managed nonoperatively (SNOM), whereas 24.7 per cent eventually required surgery. The Injury Severity Score of the OM group was highest (34) compared with the SNOM group (22) and failed NOM (FNOM; 27) groups. The mean splenic injury grade for OM, SNOM, and FNOM was 3.5, 2.4, and 3.3, respectively. The number of pre-existing conditions did not differ among the three groups. An upward trend in the failure rate of NOM was observed with increasing age (19.0%, 27.1%, and 28.3%, respectively) for three age groups, 55-64, 65-74, and 75+, but this trend was not statistically significant. Mortality rate was highest in the OM group (35.6%) compared with the successful (16.7%) and failed NOM (17.9%). Hospital length of stay (LOS) and intensive care unit (ICU) LOS were highest among patients who failed NOM (mean hospital LOS = 20.7 days, mean ICU LOS = 13.2 days) compared with OM (17.2 and 10.4, respectively) and successful NOM (12.4 and 6.9, respectively). The majority of patients > or = 55 years with blunt splenic injuries can be managed nonoperatively when carefully selected. In the subset of patients older than 55 years of age, increasing age is associated with a trend toward higher failure rates. Mortality was high regardless of management, and failure of NOM in older patients is associated with significantly longer hospital and ICU LOS.