Review Question - QID 658

The posterior cord of the brachial plexus gives rise to the 1) upper subscapular nerve 2) lower subscapular nerve 3) thoracodorsal nerve 4) axillary nerves 5) radial nerve. The upper subscapular nerve innervates the subscapularis. The lower subscapular nerve innervates teres major and also subscapularis. The thoracodorsal nerve innervates latissimus dorsi. The axillary nerves innervates deltoid and teres minor. The radial nerve innervates the triceps, brachioradialis, wrist extensors, and finger extensors. The supraspinatus is innervated by the suprascapular nerve off the upper trunk and therefore would not be affected by an injury to the posterior cord. The anatomy of the brachial plexus is shown in Illustration A.