Recurrent hemarthrosis after total knee arthroplasty.

Thirty patients who developed recurrent hemarthrosis after total knee arthroplasty were followed for an average of 27.9 months. The average interval between implantation of the prosthesis and the first bleed was 24.2 months. Nine knees responded to conservative care alone. The remaining 21 knees continued to have recurrent bleeds requiring surgical intervention. Open synovectomy was performed in 15 knees and seemed to be curative in 14 (93%). Forty-three percent of the surgically treated knees were noted to have entrapment of proliferative synovial tissue or the fat pad between prosthetic components as the cause of the recurrent bleeds. Consistent histologic findings included focal synovial hyperplasia and significant hemosiderin deposition. Although similar, these changes should not be confused with those of pigmented villonodular synovitis.