Skin and Bones

THE EXPRESSIONskin and bonesconjures vivid thoughts of cachexia, starvation, and Third World geopolitics, but little consideration of a fertile field for scientific and medical investigation. In fact, few specialties in clinical medicine seem more disparate than those of dermatology and orthopedics. An article in this issue of theArchievesdocuments, in 2 children, a rare and illustrative disease whose manifestations are specifically those of skin and bone.¹The disorder, recently described as progressive osseous heteroplasia (POH), is characterized by dermal ossification in a mosaic distribution during infancy, followed by progressive focal ossification of connective tissue that includes subcutaneous fat, fascia, and skeletal muscle.²,³ Most cases of POH appear sporadically, but siblings of several severely affected individuals have been discovered with apparent autosomal dominant transmission of a considerably more mild form of osteoma cutis.²,⁴The late consequences of heterotopic ossification in POH can be severe and include ankylosis of affected joints and