This is a rare complication of OUKA, as it is of TKA. The haemarthroses are usually of sudden onset and sometimes acute enough to demand aspiration for relief of pain. Each episode is usually short-lived, interfering with function for a few days, and subsiding spontaneously, but recurring, often several times.
Cause
The probable cause is recurrent mechanical damage to hypertrophic synovium. It is a vicious circle and recurrent haemarthrosis leads to a friable hypertrophied synovium which in leads to recurrent haemarthrosis.
Management
If a blood-clotting disorder is excluded, the prognosis for spontaneous cessation of the episodes is good. All drugs that interfere with blood clotting, such as aspirin and warfarin, should be stopped. If recurrent haemarthrosis persists, the treatment is difficult and it is worth arranging an angiogram and embolisation. Occasionally, an arthroscopy without tourniquet with synovectomy and coagulation of bleeding points helps. If the articular cartilage is destroyed or if the symptoms persist and become intolerable, conversion to TKA and synovectomy will be necessary.