Bizarre parosteal osteochondromatous proliferation and periosteal chondroma: a comparative report and review of the literature.

Bizarre parosteal osteochondromatous proliferation and periosteal chondroma are rare, benign, bony lesions that may present in the hand. Bizarre parosteal osteochondromatous proliferation was first reported in the literature by Nora in 1983, and periosteal chondroma was first reported by Lichtenstein in 1952. This report provides a unique side-by-side comparison of these lesions, illustrating each with a clinical vignette. This report, coupled with a thorough review of the literature, serves to demonstrate that the history and physical exam characteristics, as well as the radiographic and gross appearances, are insufficient to differentiate between the two lesions. Histopathologic examination is required to confirm the diagnosis.