091 Supraspinatus, Infraspinatus, and Teres Minor

Leslie Samuel introduces three intrinsic shoulder muscles: supraspinatus, infraspinatus, and Terry's minor. The video details their origins, insertions, and functions. Supraspinatus originates from the supraspinous fossa and initiates abduction of the humerus. Infraspinatus originates from the infraspinous fossa and causes external rotation. Terry's minor originates from the lateral border of the scapula, contributing to external rotation and adduction. The video concludes with a review of these muscles' roles in shoulder movement.

What is the primary action of the infraspinatus muscle when it contracts?

Identify the origin and insertion points of the teres minor muscle.

What actions are caused by the contraction of the teres minor muscle?