Melorheostosis in the upper extremity.

Melorheostosis is a rare mesodermal disease affecting the skeleton and adjacent soft tissues. Often it is incidentally detected on radiographs. In the standard radiology and orthopedics literature, melorheostosis is described as a "flowing hyperostosis, resembling dripping candle wax as an incidental radiographic finding." A 22-year-old man presented with a 2-year history of right-hand pain. Radiologic evaluation of the hand showed massive sclerotic changes in the first and second metacarpal and phalangeal bones on the right side. Further radiographic evaluation of the right upper extremity revealed the same sclerotic changes in the right scapula, humerus, radius, and scaphoid. Computed tomography (CT) scans showed a high attenuation undulating cortical hyperostosis with a "dripping candle wax appearance" involving the radial and/or dorsal aspects of humerus, radius, scaphoid, and first and second ray bones of the hand. Radionuclide triphasic bone scintigraphy showed diffuse homogenous radiotracer uptake within the entire right upper extremity involving the scapula, humerus, radius, scaphoid, and first and second metacarpals and phalangeal bones of the hand. The patient was followed conservatively, and 1-year follow-up revealed no change in the clinical, laboratory, or radiological findings. The diagnosis of melorheostosis was made on the basis of the characteristic distribution, location, and combined radiographic, CT, and radionuclide imaging features of the abnormalities. Conservative treatment was recommended for the patient. After 26 months of follow-up, despite the persistence of the radiologic findings, the patient is currently well, with no painful symptoms unless he performs forceful exercise.