Nonhemophilic hemosiderotic synovitis of the shoulder. A case report

In a nonhemophilic 72-year-old man, a persistent degenerative hemarthrosis of the shoulder joint was associated with a complete tear of the rotator cuff. Extensive, rusty synovial pigmentation and hyperplasia (hemosiderotic synovitis) mimicking pigmented villonodular synovitis (PVS) were noted at surgery. Spontaneous hemarthrosis of the shoulder includes rapid onset of severe pain, limitation of movement, subsequent appearance of a bruise on the affected shoulder and arm, and radiological evidence of joint degeneration. Hemosiderotic synovitis results from chronic intraarticular bleeding. With the breakdown of trapped hemoglobin, iron-containing hemosiderin is stored in synovial tissue producing rusty discoloration and proliferative reaction. The classic cytoarchitecture of PVS has additional subsynovial nodular proliferation of mononuclear cells. Hemarthrosis may produce significant structural alteration of joints. Its prompt recognition and the awareness of underlying causes should lead to earlier diagnosis, appropriate therapy, less joint destruction, and better outcomes.