Milwaukee shoulder syndrome

Milwaukee shoulder syndrome (MSS) (apatite-associated destructive arthritis/Basic calcium phosphate (BCP) crystal arthritis/rapid destructive arthritis of the shoulder^[1] is a rare^[2] rheumatological condition similar to pseudogout, associated with periarticular or intra-articular deposition of hydroxyapatite or basic calcium phosphate (BCP) crystals. While primarily associated with the shoulder joint, it can affect any joint in the body below the head.^[3] 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. Patients often have a history of joint trauma or overuse, calcium pyrophosphate dehydrate crystal deposition, neuroarthropathy, dialysis-related arthropathy or denervation.^[2]