Melorheostosis: segmental osteopoikilosis or a separate entity?

Abstract

Melorheostosis is a progressive hyperostotic bone disease that commonly affects the appendicular skeleton. Melorheostosis has a significant degree of overlap with other hyperostosis conditions including osteopoikilosis and likely represent varying degrees of a clinical spectrum. This is a report of 2 patients with melorheostosis who presented with different clinical presentations and involvement of different anatomic locations. One of the patients presented with foot size asymmetry along with intermittent foot pain and limping. This patient also had irregular nonblanching yellow plaque-like lesion on the forehead. The second patient presented with abnormal gait but no pain. Radiographs demonstrated endosteal hyperostosis, which were consistent with a mixed picture of melorheostosis and osteopoikilois. Genetic testing of the LEMD3 gene from a blood sample was negative in both cases. The diagnosis of melorheostosis can be made based on the clinical and radiographic features and can be challenging to differentiate from other hyperostosis conditions. Level V.