Which area experiences sensory loss in the case of a musculocutaneous nerve injury?

The lateral forearm experiences sensory loss in the case of a musculocutaneous nerve injury due to the specific anatomical distribution of the sensory innervation provided by this nerve. The musculocutaneous nerve innervates the biceps brachii and brachialis muscles and also provides sensory fibers that supply the skin on the lateral aspect of the forearm. When there is an injury to this nerve, the result is often a loss of sensation in the area it supplies, which is primarily localized to the lateral forearm.

This functional pattern highlights the importance of understanding peripheral nerve anatomy in clinical settings, as sensory deficits can indicate injury to specific nerves. Other areas, such as the medial forearm, palmar surface of the hand, and posterior hand, are innervated by different nerves—such as the ulnar nerve and radial nerve—thereby not being affected by an injury to the musculocutaneous nerve. This anatomical knowledge is crucial for effective diagnosis and treatment planning in orthotic and prosthetic practice.