Melorheostosis of the ulna.

Melorheostosis is a rare osteosclerotic bone dysplasia. It is usually characterized by dull and aching pain, reduced joint motion and contractures. Classic radiograph findings are of undulating cortical hyperostosis along the length of the bone, simulating a "dripping candlewax appearance". We report two cases of melorheostosis of the ulna bone, diagnosed 6 years apart in two different females in their early 20s. Both the patients presented with the characteristic features of dull and aching pain in the forearm and were treated conservatively. However, we misdiagnosed the first case as bone malignancy and subjected the patient to a biopsy. For the second case, with hindsight we made the correct diagnosis based only on the classic clinical history and radiographs. We believe that the discussion of a misdiagnosed case of melorheostosis with salient findings may be important for clinicians and orthopedicians in day-to-day clinical practice.