Spontaneous hemarthrosis of the knee associated with clopidogrel and aspirin treatment.

We report a case of a 76-year-old-man who developed spontaneous hemarthrosis of his right knee following clopidogrel-aspirin treatment. Clopidogrel is an ADP receptor antagonist and in combination with aspirin widely used in patients with atherosclerotic vascular disease to reduce the incidence of ischemic events. To date, no case of spontaneous hemarthrosis following clopidogrel-aspirin therapy has been reported. Prompt aspiration after discontinuing the ADP receptor antagonist-aspirin combination therapy can assist early diagnosis and may prevent further damage to the joint. In conclusion, spontaneous hemarthrosis is a possible complication following clopidogrel-aspirin therapy and is recommended to be evaluated when appropriate clinical symptoms (e.g., intraarticular effusion) present.