In this feature, AAOS Now publishes a series of images, challenging readers to diagnose the condition depicted. The images for this month’s challenge were submitted by Meagan McCarthy, a fourth-year medical student at Creighton University School of Medicine, who plans to pursue an orthopaedic surgery residency. She provides the following information:

“The patient is a 66-year-old recent Burmese immigrant with a 6-year history of soft-tissue masses of his left hand and both feet. At the time he was examined, the masses were neither painful nor tender to palpation. Radiographs of both feet and left hand are shown.”

What’s your diagnosis? E-mail your decision and rationale to aaoscomm@aaos.org

Did you get it right?
Last month, the diagnostic challenge was a 4-year old girl who had been limping for 4 weeks and who had tenderness over the dorsomedial and plantomedial midfoot on the left foot. According to Ben Grear, MD, who submitted the images, the correct diagnosis was Kohler disease (osteonecrosis of the left talar navicular, Shivajee V. Nallamothu, DO; Jeffrey Balazsy, MD; and Kristoffer West, MD, were the first to respond correctly.

Dr. Balazsy based his diagnosis on “age of presentation, no history of trauma, and classic radiographic findings of a sclerotic, wafer-shaped navicular on comparison radiographs.”

If you have a challenging case you’d like to submit, e-mail a short case description and any accompanying images to aaoscomm@aaos.org