Editor’s note: In this recurring feature, we first present a series of images (this page) for your review, and then a brief discussion of the findings and diagnosis. Before you turn to the discussion, examine these images carefully and draw your own conclusions.
History
A 56-year-old man with end-stage renal disease on peritoneal dialysis presents with a several-month history of atraumatic left shoulder pain. Radiographic (see Figure 1) and ultrasound images (see Figure 2) of the left shoulder were obtained. A diagnostic joint aspiration and biopsy were subsequently performed (see Figure 3).
For the discussion, click here.

Figure 1: Anteroposterior (AP) radiograph of the left shoulder.

Figure 2: Transverse sonographic image of the left shoulder at the level of the proximal humerus and extra-articular long-head biceps tendon.

Figure 3: Transverse sonographic image of the left shoulder during image-guided aspiration and biopsy from an anterolateral approach (needle on the right side of the image).