In posteriorly dislocated elbow, most common nerve involved is:

Due to location of the ulnar nerve i.e. posterior to the medial epicondyle, it is prone to injury in posterior dislocation of the elbow. Injury Common Nerve Involvement Anterior or inferior shoulder dislocation Axillary, (circumflex humeral) nerve Fracture surgical neck humerus Axillary nerve Fracture shaft humerus Radial nerve Fracture supracondylar humerus AIN > Median > Radial > Ulnar (AMRU) Medial condyle humerus Ulnar nerve Elbow dislocation Ulnar nerve Monteggia fracture dislocation Posterior interosseous nerve Volkman's ischemic contracture Anterior Interosseous nerve Lunate dislocation Median nerve Hip dislocation Sciatic nerve Knee dislocation C. Peroneal nerve