Osseous manifestations of sarcoidosis.

Sarcoidosis is a systemic multisystem inflammatory disease of unknown etiology. The disease is characterized by formation of non-caseating granulomas. The most common presentation is bilateral hilar lymphadenopathy and lung infiltration, but the disease is very heterogeneous, with an unpredictable clinical course. Musculoskeletal manifestations are common. Bone involvement is less frequent, and usually occurs in patients with chronic multisystem course of the disease. They are most commonly found in the phalanges of hands and feet, and are usually bilateral. The skull, long bones, ribs, pelvis, and axial skeleton may also be affected. Osseous involvement may be asymptomatic but in some cases can cause a severe disability. Imaging techniques are important for diagnosis. Radiological investigations revealed sclerotic or destructive lesions (involving also joints), cystic and punched out lesions and cortical abnormalities. Biopsy is required for differential diagnosis with respect to malignancy. Treatment is a part of systemic therapy and is not needed in all cases. Glucocorticoids and TNF-α antagonists are used for management.