Avascular necrosis of the metacarpal head: a case of Dietrich's disease and review of the literature.

BACKGROUND: Isolated avascular necrosis of the metacarpal head, also known as Dietrich's disease, is a rare entity with few cases reported previously in the literature. It has been associated with steroid use, lupus, and trauma. We describe the clinical presentation, pathogenesis, and treatment options associated with this uncommon condition.

CASE REPORT: A 36-year-old man presented with a 1-year history of a painful right middle finger metacarpophalangeal joint (MCPJ). There was no preceding history of trauma. Routine blood investigations and plain-film imaging were unremarkable. Magnetic resonance imaging (MRI) revealed a focus of osteonecrosis in the middle finger MCPJ consistent with Dietrich's disease. Given the patient's excellent functional status, conservative therapy was been successfully undertaken.

CONCLUSIONS: Dietrich's disease, although a rare entity, must be considered in the differential diagnosis of painful MCPJ, where routine blood investigations and plain-film imaging studies are unremarkable.