Calculation of trunk muscle mass and trunk muscle quality indices for walking independence in asian patients with hip fractures

Abstract

This study aimed to investigate the association between trunk muscle mass and muscle quality, as evaluated by bioelectrical impedance analysis (BIA), and the ability to walk independently in patients with hip fractures. Cutoff values for quantitative and qualitative indicators of the trunk muscles were also calculated. This study included 181 patients with hip fractures who were admitted to a convalescent rehabilitation ward. Trunk muscle mass and phase angle of the participants were evaluated on admission. The phase angle in this study was defined as the trunk muscle quality index (TMQI). Patients were classified into the independent (functional independence measure [FIM]-walk score ≥6; n=101) and non-independent (FIM-walk score ≤5; n=80) walking groups according to the FIM mobility scores at discharge. The independent group had a higher FIM gain than the non-independent group (37.0±13.6 vs. 27.1±13.5, p<0.001). Logistic regression analysis showed that the trunk muscle mass index (TMI) and TMQI were associated with the ability to walk independently. Furthermore, cutoff values of TMI and TMQI for male and female to estimate the ability to walk independently were 6.5kg/m2 and 5.7kg/m2, and 4.5° and 3.4°, respectively. TMI and TMQI are related to the ability to walk independently in patients with hip fractures. These results suggest the importance of improving trunk muscle mass and muscle quality during rehabilitation of patients with hip fractures.