Milwaukee shoulder syndrome

Milwaukee shoulder syndrome (apatite-associated destructive arthritis) is a rheumatological condition similar to calcium pyrophosphate dihydrate deposition disease (CPPD). It is associated with periarticular or intra-articular deposition of hydroxyapatite crystals. Crystal deposition in the joint causes the release of collagenases, serine proteases, elastases, and interleukin-1. This precipitates acute and rapid decline in joint function and degradation of joint anatomy. Subsequently disruption of the rotator cuff ensues.[1][2] Along with symptomatology, the disease typically presents with positive radiologic findings, often showing marked erosion of the humeral head, cartilage, capsule, and bursae. Though rare, it is most often seen in females beginning in their 50s or 60s. Diagnosis is made with arthrocentesis and Alizarin Red staining along with clinical symptoms.[3]