Hydroxyapatite deposits of the hand and wrist: a diagnosis not to be ignored.

Hydroxyapatite crystal deposition disease (HADD) of the hand and wrist is rare but can cause acute inflammatory syndromes that mimic infectious arthritis. These symptoms, which rapidly resolve with systemic anti-inflammatory drugs, are a source of diagnostic errors and inappropriate treatment. It is of crucial importance to make the diagnosis in order to avoid iatrogenic surgical management. The aim of this study was to determine the clinical and radiographic signs and the key features on which diagnosis depends. Treatment effectiveness and the course of the disease were also examined. Between 1992 and 2008, 12 patients consulted for an isolated acute local inflammatory syndrome of the hand or wrist, which was accompanied by a unique radiographic picture of calcific density. All patients were reassessed clinically and radiographically with a minimum follow-up of 2 years. All patients had presented with acute local inflammatory syndromes. Nine patients had edema and 8 had swelling and erythema. No patient had fever. The course was favorable in 11 patients and one patient required surgery. No patient had a recurrence at the mean final follow-up of 90 ± 64 months. The symptoms associated with hydroxyapatite crystal deposits suggest septic arthritis with acute joint inflammation. The radiological appearance is characteristic and corrects the diagnosis. Oral anti-inflammatory treatment gives more rapid spontaneous improvement, with complete and long-lasting resolution.