Sternocostoclavicular hyperostosis: two cases with differing dermatologic syndromes.

Sternocostoclavicular hyperostosis is a rare rheumatic condition characterized by ossification and erosion of the clavicle and the first rib, that has been shown to be associated with pustular skin lesions. We present 2 cases, one of which had features of pustulosis palmaris et plantaris and the other dissecting cellulitis of the scalp. Although the dermatologic manifestations differ, both cases have rheumatologic and roentgenographic features diagnostic of sternocostoclavicular hyperostosis.