Muscle
Supraspinatus
Rotator cuff — initiates abduction
High-yield
Initiates the first 15° of abduction; most commonly torn/impinged rotator cuff muscle. Suprascapular nerve.
Overview
The most superior rotator cuff muscle, running under the acromion to initiate abduction of the arm.
Reference facts
- Origin
Supraspinous fossa of the scapula
- Insertion
Superior facet of the greater tubercle of the humerus
- Action
Initiates abduction of the arm (first ~15°); stabilises the glenohumeral joint
- Innervation
Suprascapular nerve (C5, C6)
- Blood supply
Suprascapular artery
Clinical correlation
Painful arc and a positive empty-can test suggest supraspinatus pathology.