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There are four muscle tendons that connect to the shoulder that make up the rotator cuff. Together these four tendons stabilize the upper arm bone to the shoulder socket and allow the wide range of motion in the shoulder.
Each rotator cuff muscle performs a specific and important function for your shoulder joint: Stabilizing the head of the humerus in the shoulder joint: The supraspinatus, infraspinatus, teres minor, and subscapularis muscles all work together to achieve this.
The supraspinatus tendon is the most commonly injured tendon of the four tendons because it lies predominantly in the space between the acromion and the humeral head.
The rotator cuff is a group of muscles and tendons that surround the shoulder joint, keeping the head of your upper arm bone firmly within the shallow socket of the shoulder.
An extension is when you move your arms and stick them out behind you. The muscles involved in the flexion movement include the anterior deltoid, pectoralis major and coracobrachialis. For a shoulder extension, your body uses the latissimus dorsi, teres major and minor and posterior deltoid muscles.
| Muscle | Origin on scapula | Attachment on humerus |
|---|---|---|
| Infraspinatus muscle | infraspinous fossa | middle facet of the greater tubercle |
| Teres minor muscle | middle half of lateral border | inferior facet of the greater tubercle |
| Subscapularis muscle | subscapular fossa | lesser tubercle |
The most commonly injured rotator cuff muscle is the supraspinatus. This is in part because this muscle’s tendon passes through a very narrow space between the top of the upper arm bone and the underside of the shoulder’s top (acromion). Learn more about shoulder anatomy.
The rotator cuff consists of four muscles. These are the subscapularis, the supraspinatus, the infraspinatus and the teres minor muscles. These muscles end in short, flat, broad tendons which fuse intimately with the fibrous capsule to form the musculotendinous cuff.
Share on Pinterest Four muscles make up the rotator cuff: the subscapularis, teres minor, supraspinatus, and infraspinatus.
- applying hot or cold packs to the affected shoulder to reduce swelling.
- exercises to restore strength and range of motion.
- physical therapy.
- injecting the affected area with cortisone, a steroid that helps to reduce inflammation.
Rotator cuff muscles Supraspinatus is responsible for beginning the upward motion of your arm. After about 15 degrees, the deltoid and trapezius muscles do the work. The technical term for the motion is horizontal abduction. Infraspinatus mainly helps the rotation of your arm away from the center of your body.
Three of the four rotator cuff muscles are deep to the deltoid and trapezius muscles and cannot be seen unless those muscles are first removed and one is on the anterior side of the scapula bone and cannot be seen from the surface. On the anterior side of scapula bone is a single muscle, the subscapularis.
The primary muscles involved in the action of arm abduction include the supraspinatus, deltoid, trapezius, and serratus anterior.
| Action of the Shoulder | What the Action Looks Like (Try It Yourself!) | Primary Muscles |
|---|---|---|
| Horizontal abduction | For the start postion, lift your arms in front of you. The action occurs as you then move your arms out to the side. | Latissimus dorsi and posterior fibers of deltoid |
Overview. The human shoulder is the most mobile joint in the body. This mobility provides the upper extremity with tremendous range of motion such as adduction, abduction, flexion, extension, internal rotation, external rotation, and 360° circumduction in the sagittal plane.
A fifth muscle, the long head of biceps, while not technically part of the rotator cuff, also plays a major role. Muscles attach to bones via a tendon; the rotator cuff tendons all attach at the front shoulder on the upper arm bone called the humerus.
which of the following is NOT a rotator cuff muscle? teres major is not one of the four rotator cuff muscles. their main function is to reinforce the capsula of the shoulder and rotate the humerus in the glenoid cavity.
Rotator cuff treatment. The minimum time for recovery from rotator cuff tendinitis or a small tear is generally two to four weeks, and stubborn cases can take several months. Early on, the aim is to reduce swelling and inflammation of the tendons and relieve compression in the subacromial space.
Pain in your shoulder or at the top of your arm is often a sign of a rotator cuff injury. The rotator cuff is made up of muscles and tendons that hold the bones of the shoulder in place. A sign of rotator cuff injury is a pain or ache near the top of the arm, down the front on the outside of the arm.
Rotator Cuff Injuries. It causes swelling and pain in the shoulder that can worsen at night because your position in bed – especially if you lay on your side – can further irritate and inflame the damaged muscles and tendons of the rotator cuff.
Most rotator cuff tears cannot heal on their own unless the injury is minor. Some need short-term anti-inflammatory medication along with physiotherapy, whereas most need surgical intervention.
Generally, your rotator cuff rehab will progress with gentle range of motion exercises. This can be accomplished by using your arms to lift a wand or cane overhead. Shoulder pulleys may also be used to improve shoulder range of motion and flexibility. Isometric exercises for your rotator cuff muscles may then be done.
Rotator cuff disease: Pain can begin to radiate from your shoulder into the side of your upper arm. Torn rotator cuff: Shoulder pain may radiate down your arm to the area of the elbow.
As a group, the rotator cuff muscles are responsible for stabilizing the shoulder joint, by providing the “fine tuning” movements of the head of the humerus within the glenoid fossa. They are deeper muscles and are very active in the neuromuscular control of the shoulder complex during upper extremity movements.
Neck and shoulder pain is usually the result of strains and sprains from overexertion or bad posture. Sometimes this pain will go away on its own. Stretching and strengthening exercises can also treat the pain. Sometimes neck and shoulder pain is due to a fracture in the bones of your shoulder.
The supraspinatus muscle originates from the supraspinous fossa of the scapula, passes under the acromion, and inserts on the superior facet of the greater tubercle of the humerus. It is responsible for the initiation of arm abduction and is in control of the motion up to the first 15 degrees of abduction.
FlexionPectoralis major, deltoid, coracobrachialis, long head of biceps brachiiExtensionLatissimus dorsi, teres major, pectoralis major, deltoid, long head of triceps brachiiAdductionCoracobrachialis, pectoralis major, latissimus dorsi, teres majorAbductionSupraspinatus, deltoid
The brachialis is an elbow flexor that originates from the distal anterior humerus and inserts onto the ulnar tuberosity. The brachialis is one of the largest elbow flexors and provides pure flexion of the forearm at the elbow. [2] It does not provide any supination or pronation of the forearm.