In a man lifting up a suitcase, posterior dislocation of glenohumeral joint is prevented by:

Ans. (c) CoracobrachialisRef : Gray's 41st ed./819-821* The coracobrachialis is an elongated muscle in the superomedial part of the arm. The coracobrachialis helps flex and adduct the arm and stabilize the glenohumeral joint.* With the deltoid and long head of the triceps, it serves as a shunt muscle, resisting downward dislocation of the head of the humerus, as when carrying a heavy suitcase.* The median nerve and/or the brachial artery may run deep to the coracobrachialis and be compressed by it.* Nerve supply - Musculo-cutaneous nerve.