SURFACE LESIONS OF BONE

A surface lesion of bone may arise within the cortex, between the cort ex and the periosteum, within the periosteum, or in the tissues immedi ately adjacent to the periosteum including tendinous and ligamentous a ttachments. While these lesions generally reflect the spectrum of more common intramedullary lesions and have an appearance similar to that of their intramedullary counterparts, their unusual surface origin oft en renders diagnosis difficult. Surface sarcomas are usually of a lowe r grade than that of the intramedullary tumor, and often they have a m ore favorable prognosis. Traumatic lesions of the bone surface are com mon and should be considered in the differential diagnosis of a surfac e lesion, especially in the young or athletic individual. An elevated peripheral white blood cell count and erythrocyte sedimentation rate m ay herald an infection of the bone surface.