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

Which muscle is most commonly associated with a suspected suprascapular nerve lesion?

1. Infraspinatus

2. Teres Minor

3. Supraspinatus

4. Deltoid

The correct answer is: Supraspinatus

The muscle that is most commonly associated with a suspected suprascapular nerve lesion is the supraspinatus. The suprascapular nerve innervates both the supraspinatus and infraspinatus muscles. A lesion in this nerve can lead to weakness and dysfunction in these muscles. However, the supraspinatus is particularly significant because it plays a crucial role in the initiation of shoulder abduction and stabilization of the shoulder joint. When there is a suspected lesion of the suprascapular nerve, clinical signs often point to the weakness of shoulder abduction, making the supraspinatus muscle a primary focus in identifying this type of injury. In contrast, while the infraspinatus contributes to shoulder function and may also be affected, the supraspinatus is more prominently involved in early abduction movements, making its impairment more notable in clinical evaluations. The teres minor and deltoid muscles do not rely on the suprascapular nerve for innervation, and their involvement is less directly related to this specific nerve lesion.