INTRODUCTION: There is currently no standard definition of sarcopenia, which has often been associated with frailty. A commonly cited surrogate measure of sarcopenia is psoas muscle size. The purpose of this prospective study is to assess medical providers' capabilities to identify frail elderly trauma patients and consequent impact on outcomes after intensive care unit admission. METHODS: Trauma intensive care unit patients over the age of 50 were enrolled. A preadmission functional status questionnaire was completed on admission. Attendings, residents, and nurses, blinded to their patient's sarcopenic status, completed surveys regarding 6-month prognosis. Chart review included cross-sectional psoas area measurements on computerized tomography scan. Finally, patients received phone calls 3 and 6 months after admission to determine overall health and functional status. RESULTS: Seventy-six participants had an average age of 70 years and a corrected psoas area of 383 ± 101 mm/m. Injury Severity Score distribution (17.2 ± 8.9) was similar for both groups. Patients also had similar preinjury activities of daily living. Both groups had similar hospital courses. While sarcopenic patients were less likely to be predicted to survive to 6 months (60% vs. 76%, = 0.017), their actual 6-month mortality was similar (22% vs. 21%, = 0.915). CONCLUSION: Despite similar objective measures of preadmission health and trauma injury severity, medical providers were able to recognize frail patients and predicted they would have worse outcomes. Interestingly, sarcopenic patients had similar outcomes to the control group. Additional studies are needed to further delineate factors influencing provider insight into functional reserves of elderly trauma patients.