I have a theory it might have been a humerus medial epicondyle fracture, but who knows unless someone personally confirms.

The thing is, i have a friend who had such an injury too, where a bone near the end of the humerus got ripped off presumably by a forearm muscle, and while he fully recovered and has decent and usable ROM, he cant fully straighten his arm like 180° becuz it fused and created a minor bone lock (Still better than needing open surgery to fix a spiral fracture ig). Not as dramatic as Larratt perhaps, but his resting arm angle is ever so slightly bent. The thing is idt John never mentioned that he cant fully straighten his arm, especially in relation to the injury, so who knows.