Simple Estimation of Appendicular Muscle Mass using the Maximum Calf Circumference of Elderly Inpatients

[Purpose] To derive an equation estimating the appendicular muscle mass of elderly inpatients from the maximum calf circumference (CLFmax). [Subjects and Methods] One hundred one elderly inpatients: 57 males, 44 females, aged 74.8 ± 5.1 years. A multiple regression model with the appendicular muscle mass determined by dual-energy X-ray absorptiometry as the dependent variable, and independent variables of gender, BMI, and CLFmax was used to derive a regression equation estimating the appendicular muscle mass. [Results] According to the regression model, the inputs of gender, BMI and CLFmax could explain 80% of the appendicular muscle mass. [Conclusion] This simple estimation formula for appendicular muscle mass, using CLFmax as an index, potentially has widespread applications as an assessment tool in clinical practice for elderly inpatients.