Adjusting Anterior Thigh Muscle Measurements Using Ultrasound in Sarcopenia

We have read with great interest the recently published article by Tsukasaki et al (1). We congratulate the authors for drawing attention to regional muscle mass measurements for evaluating sarcopenia. As they highlighted, age-related muscle loss occurs initially in the anterior thigh muscles that predominantly contain fast-twitch (type II) fibers (2). Therefore, regional muscle mass and functional assessments are important for the early diagnosis and follow-up of sarcopenia (2). In this regard, computed tomography (CT), magnetic resonance imaging, ultrasound (US) and dual-energy X-ray absorptiometry (DXA) techniques give opportunity for regional muscle mass measurements. Likewise, the authors compared the relationships among regional/total muscle mass measurements, muscle power, strength and performance tests. Although we agree with them in general, we would like to add further.