Frequency of the bleeding risk in patients receiving warfarin submitted to arthrocentesis of the knee

Objective: To evaluate the potential bleeding risks of arthrocentesis in patients with different arthropathies and taking oral anticoagulants. Materials and methods: Fifteen consecutive patients, 8 males and 7 females, treated with anticoagulant therapy for atrial fibrillation (9 pts), deep venous thrombosis (4 pts) and replacement of cardiac valves (3 pts) were submitted to arthrocentesis for synovial fluid effusion due to different arthropathies. In all patients INR was ≤ 5. Nine of them were assuming AINS for the joint pain. Results: Two of fifteen patients have hemarthrosis, the first only lightly, the second more frankly. Both the patients were in therapy with AINS and INR was 3,8 and 5, respectively. Conclusions: The hemarthrosis or bleeding frequency associated with intraarticular injections in patients taking anticoagulant therapy seems not very high. Therefore the therapy with oral anticoagulans would not be an absolute controindication to the arthrocentesis execution.