May 9th 2011A 59-year-old woman had aphasia and right-sided weakness after a routine total knee replacement. CT and MRI scans revealed a large left middle cerebral artery infarct. A CT angiogram showed no significant disease of the cerebrovascular arteries. Test results for the lupus anticoagulant were positive. A venous study of the legs showed no deep venous thrombosis. She was treated with warfarin and aspirin and discharged. After speech and physical therapy, she had mild residual aphasia.