What does the subscapularis do?
The subscapularis muscle originates at the subscapular fossa and inserts into the lesser tubercle of the humerus. The muscle internally rotates and adducts the humerus.
What is the action of supraspinatus?
Action. Contraction of the supraspinatus muscle leads to abduction of the arm at the shoulder joint. The supraspinatus also helps to stabilize the shoulder joint by keeping the head of the humerus firmly pressed medially against the glenoid fossa of the scapula.
What is the function of the teres minor?
The teres minor is deep to the deltoid muscle. As a rotator cuff muscle, the teres minor stabilizes the ball-and-socket glenohumeral joint by helping hold the humeral head (ball) into the shallow glenoid cavity of the scapula (socket). The teres minor also laterally, or externally, rotate the arm at the shoulder joint.
What is the Infraspinous fossa of the scapula?
It is called the infraspinous fossa because it lies below (infra) the spine of the scapula (-spinous). Accordingly, the fossa that lies superior to the spine of the scapula is the supraspinous fossa. The infraspinatus muscle, one of the rotator cuff muscles, originates in the infraspinous fossa.
Why is it called subscapularis?
The subscapularis muscle is a large triangular shaped muscle that originates from the subscapular fossa. The term “subscapularis” means under (sub) the scapula (wingbone).
What muscle sits in the Infraspinous fossa?
infraspinatus muscle
In human anatomy, the infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa….
| Infraspinatus muscle | |
|---|---|
| Origin | infraspinous fossa of the scapula |
| Insertion | middle facet of greater tubercle of the humerus |
How do you train the supraspinatus?
Using the criteria that the best exercise to isolate and strengthen the supraspinatus should maximize supraspinatus activity while minimizing deltoid activity, the researchers determined that shoulder external rotation at 0° of abduction with an elastic band and prone external rotation were preferable.
What muscle raises arm above shoulder?
Trapezius is responsible for elevating the shoulder blade and rotating it during arm abduction. Deltoid is responsible for flexion and medial rotation of the arm.
What is the action of the teres major and minor?
Teres major is a thick and ovoid muscle in the upper arm. Despite their similar names, Teres major has different actions and innervation from the Teres minor. It’s mainly responsible for the medial rotation of the arm and it also contributes to static posture and arm-swinging.
Where is the Infraspinous process?
scapula
Infraspinous Fossa – large scooped out hollow beneath the spine of the scapula where the infraspinatus originates. Subscapular Fossa – this is on the anterior (front) surface of the shoulder blade.
What do you need to know about the infraspinatus test?
The Infraspinatus test is used to test for subacromial impingement or rotator cuff tears. The patient should be standing, with the arm in a neutral position and the elbow flexed to 90 degrees.
Is the infraspinatus part of the rotator cuff?
The infraspinatus is a thick triangular muscle that occupies much of the infraspinous fossa of the scapula. It is a member of the rotator cuff, commonly remembered by the mnemonic “SITS” (supraspinatus, infraspinatus, teres minor, subscapularis).
Where is the infraspinatous fossa on the human body?
Infraspinatous fossa shown in red. Left scapula. Dorsal surface. Infraspinatous fossa labeled at center.
Where does the tendinous fiber of the infraspinatus come from?
It originates with strong muscle fibers directly from the medial two-thirds of the infraspinous fossa, whereas its tendinous fibers arise from the ridges of the fossa. Some fibers also originate from the deep surface of the thick infraspinous fascia covering the infraspinatus muscle, that separates it from the teres major and minor muscles.