College of Massage Therapists of British Columbia (CMTBC) Practice Exam

Which nerve innervates the lateral pectoralis major muscle?

1. Thoracodorsal nerve

2. Pectoral (lateral) nerve

3. Musculocutaneous nerve

4. Axillary nerve

The correct answer is: Pectoral (lateral) nerve

The lateral pectoralis major muscle is primarily innervated by the pectoral (lateral) nerve. This nerve is responsible for providing motor innervation to the pectoralis major muscle, specifically the clavicular head, which contributes to shoulder flexion, adduction, and internal rotation. The lateral pectoral nerve arises from the superior trunk of the brachial plexus, typically from the lateral cord, and plays a crucial role in the proper functioning of the pectoralis major. Understanding the innervation of muscles is essential in the field of massage therapy, as it aids in identifying muscular dysfunction, understanding movement patterns, and providing effective treatments. In this context, recognizing the specific nerve associated with a muscle helps therapists tailor their approaches for optimal client outcomes.