Delayed Life-Threatening Hemorrhage Caused by Cranial Tibial Artery Pseudoaneurysm in Two Dogs

Two adult dogs were presented at 25 and 30 days following tibial external skeletal fixator placement (case 1) and tibial plateau leveling osteotomy (case 2), respectively. Clinical signs at presentation for each of them included acute onset lethargy, non-weight-bearing lameness, and hemorrhage at the surgical site with large hematoma formation. On admission, emergency whole blood transfusion was required in case 2 with a preoperative packed cell volume of 13%. Both dogs were diagnosed with pseudoaneurysm of the cranial tibial artery based on color Doppler ultrasonography. Additionally, computed tomography angiography was performed in one dog. Surgical treatment of the dogs included ligation of the cranial tibial artery supplying the pseudoaneurysm and curettage of hematoma. The surgery was completed without complications in case 1, but case 2 experienced inadvertent rupture of pseudoaneurysm with significant blood loss, which required another whole blood transfusion during the procedure. Both dogs had excellent functional recovery with no recurrence of clinical signs. We hypothesized that pseudoaneurysms were primarily caused by trauma secondary to placement of surgical implants or osteotomy. For orthopedic surgeons, it is important to recognize clinical signs of a potential tibial arterial pseudoaneurysm, as early surgical intervention may prevent loss of limb or life.