GENERAL INFORMATION
The supraspinatus is a muscle located in the shoulder region. It is one of the four muscles that make up the rotator cuff. The supraspinatus muscle plays a crucial role in shoulder movements, particularly in initiating abduction of the arm.
ORIGIN
This muscle originates from the supraspinous fossa, which is a depression on the posterior aspect of the scapula (shoulder blade).
INSERTION POINT
The muscle inserts into the greater tuberosity of the humerus (upper arm bone). It attaches to the bone via a tendon that passes beneath the acromion process.
MAJOR ARTERIES
This muscle receives its blood supply from branches of the suprascapular artery.
NEURAL INNERVATION
The supraspinatus muscle is innervated by the suprascapular nerve, which arises from the upper trunk of the brachial plexus (C5-C6).
TRIGGER POINT
Trigger points can develop in the supraspinatus muscle, causing localised pain as well as tenderness. These trigger points can be associated with muscle overuse, poor posture, or trauma.
CONCENTRIC FUNCTION
Contraction of the supraspinatus muscle initiates and assists in shoulder abduction (lifting the arm away from the body). It helps to raise the arm from a hanging position.
ECCENTRIC FUNCTION
This muscle has a crucial eccentric function during controlled shoulder movements, particularly in managing the descent of the arm during shoulder adduction.
ISOMETRIC FUNCTION
Isometric contraction of the supraspinatus muscle provides stability and support to the shoulder joint, maintaining proper alignment as well as preventing excessive movement.
RELATED MUSCLE SCIENTIFIC NAMES
- Supraspinatus: This muscle is part of the rotator cuff group and is crucial for initiating the abduction of the arm.
ANTAGONIST
- Infraspinatus: Located on the posterior scapula, this muscle externally rotates the arm as well as works opposite to the supraspinatus.
- Teres minor: Another muscle on the posterior scapula, it assists with external rotation of the arm and acts antagonistically to the supraspinatus.
COMMON INJURIES
- Supraspinatus tendonitis: Inflammation due to overuse or repetitive motions, leading to shoulder pain.
- Supraspinatus tear: Partial or complete tear from trauma or chronic degeneration, resulting in weakness as well as pain.
- Impingement syndrome: Compression causing pain and limited range of motion in the shoulder.
EXERCISES
- Shoulder abduction with dumbbells: Lift the arm away from the body against resistance, targeting the supraspinatus.
- Lateral raises: Perform lateral raises with dumbbells to strengthen the supraspinatus.
- Cable abduction exercises: Use a cable machine to perform abduction exercises, focusing on the supraspinatus.
- External rotation with bands: Strengthen the rotator cuff muscles, including the supraspinatus, using resistance bands.
- Isometric shoulder abduction: Hold the arm in an abducted position or resist external forces to engage as well as strengthen the muscle.
STRETCHES
- Cross-body stretch: Bring the affected arm across the chest and use the opposite hand to gently pull it closer to the body, stretching the supraspinatus.
- Wall stretches: Place the hand on a wall at shoulder height and lean the body away, stretching the supraspinatus.
- Doorway stretch: Stand in a doorway, place your arms on the frame, and lean forward to stretch your shoulder muscles.
- Sleeper stretch: Lie on your side with the affected arm bent, and use the other hand to push the forearm down gently.
- Overhead stretch: Reach the affected arm overhead and bend the elbow, using the other hand to push the arm down gently.
