Bone sarcoidosis.

Sarcoidosis of the bone has been observed in 24 patients for up to 43 yr. It was always present in hands and/or feet and also elsewhere in 4 other patients. Soft-tissue swelling preceded the radiological abnormality for up to 4 yr in 9 patients accompanied it once, followed it once, and was absent in 13 (55%). Bone involvement was usually an incidental finding when sarcoidosis presented elsewhere, including lupus pernio (50%) and other chronic skin lesions (41%), lungs (75%), eyes (51%), lymph nodes (21%), liver (17%), spleen (13%), parotids (13%), facial palsy in 2 patients and erythema nodosum in 1. Pulmonary infiltration, with or without lymphadenopathy, was evident in three-fifths of the patients and hilar adenopathy alone in one-fifth. Sarcoid tissue was observed in the bone, but not in the surrounding soft-tissue swelling of 2 amputated fingers. There were 3 types of bone lesions: a) Lytic in 20 patients; minute 1-mm cortical defects or larger, usually rounded defects that on healing become corticated leading to punched-out "cysts". b) Permeative in 8 patients; these showed progressive cortical tunnelling with remodelling of trabecular and cortical architecture. c) Destructive in 3 patients, with secondary joint-surface involvement and in one a periosteal reaction.