Fig. 1

Ultrasound of a 68-year-old man without type 2 diabetes mellitus or obesity. This long-axis sonographic image of the left deltoid muscle (open arrows) is obtained at the anterior aspect of the supraspinatus tendon (S), at its insertion at the greater tuberosity (solid star) of the proximal humerus (H). The 3 circles overlying the deltoid muscle indicate the location of the grayscale pixel intensity region of interest measurements that were obtained to calculate the mean deltoid muscle value. The open star indicates the location of the single region of interest measurement obtained on the osseous cortex of the humeral head, near the anatomic neck. Notice the hypoechoic appearance of the deltoid muscle. The patient had a body mass index of 24 kg/m2. The calculated ratio (deltoid muscle/humeral cortex) for this patient was equal to 0.29, consistent with a non-type 2 diabetes mellitus status