Calcific periarthritis: more than a shoulder problem: a series of fifteen cases.

Background: Calcific periarthritis, referring to a circumscribed juxta-articular deposit of minute non-birefringent mineral grains, is rarely the clinical diagnosis accompanying a pathologic specimen. Familiarity with the clinical, pathologic, and radiologic manifestations of calcific periarthritis, particularly when encountered adjacent to joints other than the shoulder, facilitates diagnosis and may obviate biopsy, avoid confusion with other entities, and speed appropriate treatment.
Methods: Pathologic specimens that fulfilled the criteria for a diagnosis of calcific periarthritis were prospectively collected. Clinical history and radiologic studies were acquired and analyzed. Well-controlled special stains were employed on two specimens with a neutrophilic infiltrate that excluded fungal and bacterial agents, as corroborated by microbiologic cultures showing no growth.
Results: Over a five-year period, fifteen patients between the ages of thirty-one and eighty-eight years (mean age, fifty-nine years) presented to various local healthcare providers for treatment of juxta-articular swelling that was subsequently determined to be calcific periarthritis. In seven patients, deposits were alongside a toe joint; in five, alongside a finger joint; and in three, involving the shoulder. The majority of the patients were female (73%). No patient had a documented recurrence of calcific periarthritis in follow-up periods ranging from eighteen to eighty-seven months (average forty-five months).
Conclusions: Of twelve histologically verified cases of calcific periarthritis adjacent to joints other than the shoulder, in only one patient (toe) was the preoperative clinical diagnosis accurate, which signals the need for greater awareness of this entity as a differential diagnostic option.