IS case 446: Melorheostosis and osteopoikilosis
Imaging Sciences URMC 2010
Publication Date: 2010-08-30
Patient is a 15-year-old girl seen following a twisting injury to her right ankle during a volleyball game, with concern for fracture. The radiographs showed no acute injury, however were remarkable for scattered sclerotic foci consistent with a combination of melorheostosis and osteopoikilosis. A bone survey confirmed bilateral melorheostosis and osteopoikilosis of the lower extremities.
Plain radiographs of the right tibia-fibula, right ankle, and right foot showed no acute injuries. There was cortical thickening of the distal tibia and fibula. This appearance is the classic or so called "candle wax" of melorheostosis. Scattered small sclerotic foci were seen in the calcaneus, talus and cuboid which are consistent with osteopoikilosis.
Melorheostosis and osteopoikilosis
Melorheostosis (Leri disease) is a rare idiopathic condition, belonging to the group of disorders termed mixed sclerosing dysplasias. These disorders demonstrate both endochondral and intramembranous failure of ossification. The thickened cortical new bone generally accumulates on one side towards the end of long bones.
Melorheostosis may be associated with joint stiffness/pain and bone pain, that increases with activity. One bone (monostotic) or an entire limb (monomeli) may be affected. Rarely the lesions may be found in more than one limb (polyostotic).
Diagnosis can be made by plain radiograph alone, which demonstrates a thickened cortex which resembles melted wax dripping down the side of a candle. Occasionally ossifications can be seen in the adjacent soft tissue as well. Melorheostosis is a chronic condition, with no definitive treatment.
Osteopoikilosis (osteopathia condensans disseminata) is a hereditary disorder that is also related to the failure of endochondral ossification. The condition is generally asymptomatic and found incidentally on radiographs. The findings on plain radiographs are small sclerotic foci that are generally para-articular and present in the long bones and pelvis although any bone may be affected.
These two conditions may occasionally co-exist in the same patient, as in this case and constitutes a so called overlap syndrome.
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