Indirect traumatic musculocutaneous nerve injury confused with static line injury: A case report

Abstract

The musculocutaneous nerve is rarely injured because it is short and is located deep in the shoulder and arm. Damage is usually caused by direct injuries, including stabbing, explosion, and surgery in a war setting. Although indirect injury of the musculocutaneous nerve is extremely rare, it occurs in various situations. In military parachuting-related activities, musculoskeletal injury occurs most commonly, and static line injury is known as rupture of the biceps brachii tendon. However, musculocutaneous neuropathy can also result from secondary injury by the static line. The musculocutaneous nerve goes together with the biceps brachii muscle, and the musculocutaneous nerve could overstretch and compress within the coracobrachialis muscle where the nerve is relatively fixed due to the overloading of the upper arm with shoulder extension. This report focuses on the indirect musculocutaneous nerve injury with axonotmesis following an overloading event by the static line during military parachuting. In this case, some physicians may confuse nerve injury with static line injury, leading to delays in the diagnosis of neuropathy. If the biceps brachii muscle is damaged due to trauma, checking for the accompanying musculocutaneous nerve injury is necessary.