Deposition of hydroxyapatite

Milwaukee Shoulder

Deposition of hydroxyapatite or basic calcium phosphate are present within the joint and in periarticular locations such as around the shoulder area and are associated with osteoarthritis.

These crystals are implicated in destruction syndrome known as Milwaukee*** shoulder.

Hydroxyapatite crystals can be detected in synovial fluid , but these crystals are generally nonbirefringent*** , it is not possible to detect them by polarized microscopy.

They can be detected with Alizarin red S*** stain under routine light microscopy.