Question

A massage therapist client complains of numbness located around inferior attachment of the deltoid muscle. Lesion of the ________ nerve is the most likely cause of the numbness.

Answer 1

Numbness around the inferior attachment of the deltoid muscle is most likely caused by a lesion of the axillary nerve, which innervates this region and is critical for both motor and sensory functions.

Step-by-step explanation:

The lesion of the axillary nerve is the most likely cause of numbness located around the inferior attachment of the deltoid muscle. The axillary nerve travels through the quadrilateral space and innervates the deltoid muscle and the skin overlying it. Damage to this nerve can cause both a loss of motor function, leading to difficulty in abducting the arm, and sensory deficits, resulting in numbness in the regimental badge area (lateral aspect of the shoulder).