A bleeding pseudoaneurysm of the lateral genicular artery after total knee arthroplasty—A case report

A 64-year-old man with a history of hypertension, benign prostatic hypertrophy, chronic obstructive pulmonary disease and a dilated aorta had undergone total knee replacement of his left knee due to severe disabling osteoarthrosis. The preoperative physical examination revealed mild effusion, a varus deformity of 20 degrees, and a normal but painful range of motion and mediolateral instability of both knees. Laxity was present in his shoulder, elbow and wrist joints. Plain radiographs of the knees demonstrated advanced degenerative changes with severe narrowing of the medial joint spaces bilaterally. The left knee was chosen for surgery, since it was the more painful and disabling. A posterior stabilizer prosthesis was implanted and lateral release of the patellar retinaculum was carried out. There were no intraoperative complications and the alignment and stability of the prosthesis was satisfactory. The course during the first postoperative month was uneventful, except for a hematoma on the anterolateral side of the knee where the lateral release had been performed: the hematoma appeared one day postoperatively and gradually dissolved spontaneously.

4 weeks after surgery, the patient started to complain of increasing pain and gradual swelling of his operated knee. He presented to the emergency room due to agonizing knee pain 2 weeks later. His left knee was very swollen, especially on the anterolateral side. It was warm and tender and any passive or active motion aggravated the pain. The hemoglobin level was 7.8 mg/dL, the white blood count was 7.6×10³/μL, the coagulation profile was normal and the sedimentation rate was 42 mm/hr (the sedimentation rate before surgery being 41 mm/hr).

The patient was admitted to the orthopedic department and arthroscopy was performed 2 days afterwards. The knee was lavaged and several blood clots were drained. No active bleeding was detected. Improvement in the pain and swelling lasted for 5 days. On the 6th day after the arthroscopy, the patient complained of an acute, sharp agonizing pain and a sudden worsening of the swelling of the operated knee. The findings of the physical examination were similar to those on the day of admission. The knee was again swollen and tender and the pain was aggravated by any motion. An angiographic examination was performed because of suspected recurrent bleeding, and a bleeding pseudoaneurysm of the superior lateral genicular artery was demonstrated (Figure 1A). Using a microcatheter, a super-selective catheterization of the lateral genicular artery was performed and the artery was embolized by means of 3-mm coils (Figure 1B). During a second arthroscopy several hours after the embolization, blood clots were drained and the prosthetic joint was lavaged. The patient experienced instant relief and there was a major improvement in the extent of pain, swelling and range of motion. 24 hours after the embolization, a pseudoaneurysm in the puncture site of the femoral artery was diagnosed by ultrasonography and treated successfully with external pressure. The patient was discharged 2 days later.