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 Thomas Alexander Jr, MD, a resident member at the University of Tennessee–Campbell Clinic. Dr. Alexander also provided the following information:

The patient is an 18-year-old male with a 5-month history of gradually worsening dorsal midfoot pain. The patient denies any history of trauma and reports that the pain is worse with ambulation. Initially, aspirin was sufficient to relieve the pain, but it is no longer effective. What’s your diagnosis?

Find the answer to this month’s challenge below

Larger image (PDF)

Answer
According to Thomas Alexander Jr, MD, who submitted the case, the diagnosis is osteoid osteoma of the navicular. According to Dr. Alexander, a computed tomography (CT) scan is the preferred diagnostic modality because studies have shown that relying solely on magnetic resonance image (MRI) findings results in a 35 percent chance of misdiagnosis. Treatment choices include observation with administration of nonsteroidal anti-inflammatory drugs to control the pain, burr-down technique, CT-guided percutaneous excision, and percutaneous radiofrequency ablation.

Send AAOS Now your case
Do you have a challenging case you’d like to submit for publication? Email a short case description and any accompanying images to aaoscomm@aaos.org