From the Research
The nerve responsible for teres minor movement is the axillary nerve, specifically its posterior branch, as confirmed by the most recent study 1. This nerve originates from the posterior cord of the brachial plexus, specifically from the C5 and C6 nerve roots. The axillary nerve innervates both the teres minor muscle and the deltoid muscle, allowing them to function properly. The teres minor is a small muscle of the rotator cuff that helps with lateral rotation of the arm at the shoulder joint. When the axillary nerve stimulates the teres minor, it contracts to rotate the humerus laterally (externally) and also assists with adduction of the arm. This nerve travels through the quadrangular space in the shoulder region before reaching the teres minor muscle. Some key points to consider about the axillary nerve and its relation to the teres minor include:
- The axillary nerve divides into anterior and posterior branches in the quadrangular space, with the posterior branch being responsible for innervating the teres minor muscle, as noted in 2.
- Damage to the axillary nerve can result in weakness in external rotation of the shoulder and potential atrophy of the teres minor muscle, which may contribute to shoulder instability and reduced function, as discussed in 3.
- The teres minor muscle plays a crucial role in shoulder movement, and its innervation by the axillary nerve is essential for proper function, as highlighted in 4 and 5.
- Recent studies, such as 1, have explored nerve transfer techniques to restore function in cases of axillary nerve injury, underscoring the importance of understanding the anatomy and function of the axillary nerve and its branches.