The C5 myotome refers to a specific segment of the spinal cord that corresponds to the fifth cervical vertebra. It is responsible for controlling certain muscles in the upper body, particularly those involved in shoulder movement and elbow flexion. The primary muscles affected include the deltoid and biceps brachii. Damage to the C5 myotome can lead to weakness or paralysis in these muscle groups, impacting a person's ability to lift their arm or bend their elbow. This condition is often assessed in clinical settings to determine the extent of spinal cord injuries or neurological disorders.