Utilizing psoas muscle cross-sectional area to predict functional outcome

Abstract

Background: This study evaluated psoas muscle area (PMA) as a predictor of frailty and functional outcome in trauma patients. Methods: The cohort included 211 trauma patients admitted to an urban level I trauma center from March 2012 to May 2014 who consented to participate in a longitudinal study and underwent abdominal-pelvic computed tomography scans during their initial evaluation. Physical component scores (PCS) of the Veterans RAND 12-Item Health Survey were administered to assess physical functionality at baseline and at 3, 6, and 12 months after injury. PMA in mm2 and Hounsfield units was calculated using the Centricity PACS system. Statistical models were stratified by injury severity score (ISS), <15 or ≥15, and adjusted for age, sex, and baseline PCS. Follow-up PCS were analyzed using general linear regression models. Results: For participants with an ISS <15, increased PMA was significantly associated with higher PCS at 3 (P = 0.008), 6 (P = 0.02), and 12 months (P = 0.002), although this relationship was not statistically significant for ISS ≥15 (P = 0.85, 0.66, 0.61). Conclusion: For mild to moderately injured (but not seriously injured) patients, those with larger psoas muscles experience better functional outcomes after injury.