Milwaukee Shoulder Syndrome

Milwaukee shoulder syndrome (MSS) is a rare, rapidly destructive arthropathy associated with calcium hydroxyapatite crystal deposition. This condition is a combination of rotator cuff tear, osteoarthritic changes, noninflammatory joint effusion containing crystals, synovial hyperplasia, cartilage and subchondral bone destruction, and multiple osteochondral loose bodies. This article discusses pathophysiology, clinical presentation, differential considerations, and magnetic resonance imaging findings of MSS. (Journal of Surgical Orthopaedic Advances 26(1):54–57, 2017) Key words: apatite-associated destructive arthritis, calcium pyrophosphate crystals, HADD, hydroxyapatite crystal, Milwaukee shoulder syndrome, MRI