Acute calcific periarthritis secondary to calcium hydroxyapatite crystal deposition in the wrist: a case report.

Acute calcific periarthritis (ACP) is an unusual cause of monoarticular pain characterised by the deposition of calcium hydroxyapatite in the peri-articular and intra-articular tissues. Although the most commonly affected joint is the shoulder, other joints may be involved, including the wrist. This case report describes a 57-year-old female presenting with wrist pain and swelling associated with amorphous calcification overlying the lunate.