Review Question - QID 217935

Figure A is the AP and lateral radiograph, respectively, of a 45-year-old farmer who presented to your clinic after a fall onto an outstretched hand five days ago. He notes "a bit" of elbow pain, and has had difficulty performing his work duties. The patient has a positive gravity-assisted varus stress test, and the patient states that his elbow "sounds like crispy rice cereal" when he moves it. You bring the patient to the operating room and perform open reduction and internal fixation of the fracture shown. If the elbow remains unstable, which of the following is the insertion of the ligament you should next address surgically?