A 42-year-old man is performing his final deadlift at the annual CrossFit games when he suddenly experiences severe pain in his right arm and is unable to continue. Physical examination is significant for medial brachial ecchymosis, swelling and tenderness over the antecubital fossa, and significantly diminished supination strength. Radiographs are unremarkable and an MRI is shown in Figure A. Given his age and activity level, he is taken for primary surgical repair utilizing a single-incision technique with combined cortical button and interference screw fixation. When the patient returns to clinic, he is found to have experienced the most common neurologic complication associated with this procedure. What is the course of the affected nerve?