Tophaceous pyrophosphate deposition with extensor tendon rupture.

Tophaceous deposition of calcium pyrophosphate dihydrate (CPPD) crystals is considered unusual as is deposition within tendon sheaths. Associated tendon rupture is described but is rare. We report a lady with tophaceous CPPD deposition at the wrist, a previously unreported site. Contrary to previous cases, this occurred in the setting of symptomatic, polyarticular, pyrophosphate arthropathy. An additional point of interest was development of associated extensor tendon rupture with features favouring a non-inflammatory mechanism of tendon damage.