Fig. 1 Anteroposterior radiograph of the left hip and thigh of an 18-year-old patient complaining of pain and difficulty with ambulation.

AAOS Now

Published 12/1/2013

What's Your Diagnosis?

In this feature, AAOS Now publishes a series of images, challenging readers to diagnose the condition depicted.

This month’s challenge was submitted by David M. Waespe, MD, orthopaedic chief resident at the University of Mississippi Medical Center.

Dr. Waespe writes that an 18-year-old female patient was seen for left lower extremity pain and difficulty with ambulation. The patient had had several previous surgeries over the years on her left leg, beginning with a club foot release and ending with a through-the-knee amputation. In addition, she had experienced numerous wound healing problems.

An examination of her left thigh found that the through-the-knee amputation resulted in well-healed incisions. A cord-like lesion was found on her posterior medial thigh distally that was painful when palpated. The patient also complained of pain under her patella. She has a slight flexion contracture of her hip.

Based on the radiograph shown (Fig. 1), what’s your diagnosis?

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

Find the answer to this month’s challenge below.

Answer
According to David M. Waespe, MD, who submitted the case, the diagnosis is melorheostosis. This rare, non-familial sclerosing bony dysplasia has a poorly understood etiology. Melorheostosis is a mixed sclerosing dysplasia with disturbance of both endochondral and intramembranous ossification, in which disordered intramembranous ossification dominates. Pain and joint contractures may be common.

“The hallmark radiographic findings are asymmetrical bands of sclerosis in an irregular, linear pattern often described as molten wax dripping down from one side of a candle,” explained Dr. Waespe. “Treatment is designed to relieve pain and improve function and could involve soft-tissue contracture releases such as capsulectomy, fasciotomy, and tendon lengthening, as well as correction of bony deformities, analgesia to control pain, bracing, and, eventually, amputation. Melorheostosis is progressive and not life-shortening, but may lead to significant morbidity.

More information on this rare disease is available from the National Institutes of Health Office of Rare Diseases Research (http://rarediseases.info.nih.gov).