Review Question - QID 220864

An 11-year-old female presents to the emergency department for evaluation of a left upper extremity injury after falling while performing aerial maneuvers at a local gymnastics camp. Radiographs are obtained, which demonstrate a Bado Type I Monteggia injury. An attempted reduction is performed, and the ulna is anatomically reduced; however, the radial head remains dislocated despite repeated attempts. The function of the most likely interposed structure involves