Review Question - QID 214676

An 18-year-old football player is tackled and sustains an injury to his right lower extremity. There is obvious deformity at the knee and he is immobilized on the field and taken to a nearby hospital. Lateral radiograph is seen in Figure A. Successful reduction is performed, followed by a CT with angiography, which demonstrates intimal tearing in the popliteal artery. Dorsalis pedis and posterior tibial pulses are not dopplerable in the right lower extremity. You elect to place a knee-spanning external fixator before vascular intervention. Initial ligamentous examination in the operating room demonstrates increased anterior and posterior laxity as well as increased laxity with varus stress. Which additional physical exam finding would be indicative of a commonly associated injury given this patient's presentation?