[Periarticular mineralization of the finger].

Periarticular mineralization is a clinical disorder, which is typically found at the shoulder, knee and hip joint and only rarely diagnosed at the finger joints. Periarticular ossification is a different entity and has to be distinguished from periarticular mineralization. The typical symptoms of this disorder are pain and swelling of the joint that resolves spontaneously within 3-6 months. We report on a case of periarticular mineralization of the metacarpophalangeal (MCP) joint of a 39-year-old woman. Diagnosis was made by X-ray based on findings in the form of opaque mineralizations. There was no pain relief with conservative treatment and operative treatment was performed. Histological and electron microscope analysis of the mineralization showed hydroxyapatite crystals and chondrogenic metaplasia of the surrounding fibroblasts. The patient was symptom-free soon after treatment.Usually, the therapy of the periarticular mineralization is conservative; only exceptional cases with persistent pain and swelling need operative treatment. Acute periarticular mineralization of the hand is rare and often misdiagnosed as infectious arthritis.