Fig. 1From: Reliability of ultrasound measurements of quadriceps muscle thickness in critically ill patientsUltrasound assessment of the quadriceps femoris muscle thickness. a Anatomical diagram locating the “midpoint” and the “two-thirds” measurement sites. From Wikimedia Commons. b Transverse ultrasound section made by linear probe at the midpoint site. RF: rectus femoris; VL: vastus lateralis; VM: vastus medialis; VI: vastus intermediusBack to article page