Right Arm Muscles Affected by Brachial Stretch Injury
This exhibit compares a normal child’s arm innervation to one affected by a brachial stretch injury. Normally, the C5-T1 nerve roots exit the cervical spine and merge to form the brachial plexus. The brachial plexus then gives rise the nerves which control all muscle movements in the arm and hand. A brachial stretch injury damages the exiting cervical nerve roots, causing abnormal nerve transmission to the biceps brachii and abductor pollicis brevis.