What does the infraspinatus do

The infraspinatus muscle’s action on the shoulder is primarily through its function as a rotator cuff muscle providing glenohumeral

What movement does the infraspinatus muscle do?

Action. Infraspinatus is the main external rotator of the shoulder joint. It assists in producing shoulder extension. With the arm fixed, it abducts the inferior angle of the scapula.

What does infraspinatus tendon do?

The infraspinatus is one of four muscles that make up the rotator cuff, which helps your arm and shoulder move and stay stable. Your infraspinatus is in the back of your shoulder. It attaches the top of your humerus (the top bone in your arm) to your shoulder, and it helps you rotate your arm to the side.

What movement is infraspinatus?

In human anatomy, the infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa. As one of the four muscles of the rotator cuff, the main function of the infraspinatus is to externally rotate the humerus and stabilize the shoulder joint.

What do the supraspinatus and infraspinatus do?

The supraspinatus muscle abducts the upper arm (test with the arm at the side to avoid overlap with deltoid muscle function). The infraspinatus muscle externally rotates the upper arm at the shoulder.

What is the antagonist to Infraspinatus?

The infraspinatus: agonistic: anterior deltoid, latissimus dorsi, lower trapezius, pectoralis major, pectoralis minor, serratus anterior, teres minor. antagonistic: middle deltoid, middle trapezius, posterior deltoid.

Is the Infraspinatus a flexor or extensor?

Insertion: Distal to the greater tubercle of the humerus. Action: Outward rotator and abductor of the humerus and a flexor or extensor of the shoulder joint, depending on the position of the joint when the muscle contracts.

What is Subscap?

The subscapularis is a muscle in your shoulder that helps you internally rotate your arm. … The subscapularis connects from your shoulder blade to your humerus, or upper arm bone. All the muscles of the rotator cuff, including the subscapularis, can tear from overuse, trauma, or age-related conditions.

What type of muscle is Infraspinatus?

OriginInfraspinous fossa of scapulaBlood supplySuprascapular artery, circumflex scapular arteries

What action does the latissimus dorsi perform?

Latissimus dorsi works collaboratively with the teres major and pectoralis major to perform actions of the upper extremity. Together, these muscles will work to adduct, medially rotate and extend the arm at the glenohumeral joint.

Article first time published on

Where does a torn Infraspinatus hurt?

The infraspinatus muscle-tendon is attached to the greater tubercle of the humerus bone. Infraspinatus pain often presents as pain on the front side of the shoulder. Infraspinatus muscle and tendon pain began often without trauma, dubbed as an “overuse” injury.

What does an infraspinatus tear feel like?

Infraspinatus tendon tears frequently occur in overhead athletes, as a result of overuse injury, or in chronic shoulder instability. The main complaints are pain while sleeping, weakness in the affected arm, and inability to move the arm in certain motions.

Is a supraspinatus tear painful?

The tear can be partial or full-thickness. Pain, loss of range of motion and weakness is the 3 most common symptoms. Supraspinatus tears can be managed conservatively, with NSAID’s and physiotherapy, as well as surgically to repair the tear.

Is the subscapularis the same as infraspinatus?

Compared to the other rotator cuff muscles, the infraspinatus has the second-largest anatomic footprint on the humerus. The subscapularis has the largest. The infraspinatus also acts on the scapula. … Scaption makes the scapula more mobile, which assists the other shoulder muscles in allowing for full shoulder abduction.

How many rotator cuffs are in your shoulder?

All four rotator cuff muscles work together to centralize your humerus bone in the shoulder joint.

What are the 5 rotator cuff 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.

How big is the infraspinatus tendon?

Rotator cuff tendonMedial to lateral widthAnterior to posterior lengthMean (mm)Mean (mm)Supraspinatus1623Infraspinatus1828Teres minor2129

What are the four sits muscles?

They are also referred to as the SITS muscle, with reference to the first letter of their names (Supraspinatus, Infraspinatus,Teres minor, and Subscapularis, respectively). The muscles arise from the scapula and connect to the head of the humerus, forming a cuff around the glenohumeral (GH) joint.

Is the pectoralis major a synergist?

clavo-deltoid (flexes humerous): synergist: teres majorm subscapularis pectoralis major.

What is the opposing muscle to the latissimus dorsi?

Latissimus dorsiAntagonistDeltoid and trapezius muscleIdentifiersLatinMusculus latissimus dorsiTA98A04.3.01.006

What is the attachment of infraspinatus?

Insertion of the Infraspinatus Specifically, the infraspinatus inserts onto a large, round prominence located at the top, outer portion of the humerus. This prominence is called the greater tubercle or greater tuberosity. The infraspinatus muscle inserts onto the greater tubercle of the humerus.

How do I strengthen my infraspinatus?

Previous studies have reported that prone external rotation with horizontal abduction (PER), side-lying wiper exercise (SWE), and standing external rotation (STER) were effective exercises for strengthening the infraspinatus.

What is Sasd bursitis?

The subacromial-subdeltoid bursa (SASD) is a potentially pain-sensitive structure of the glenohumeral joint. Along with the rotator cuff tendons, it has been implicated as a primary pathology in painful shoulder conditions of overhead athletes (eg swimmers, weightlifters, gymnasts, tennis players etc).

What does a positive Gerber's lift-off test indicate?

Positive. The ability to actively lift the dorsum of the hand off the back constitutes a normal lift-off test. Inability to move the dorsum off the back constitutes an abnormal lift-off test and indicates subscapularis rupture or dysfunction.

Can a full thickness tear of the supraspinatus heal without surgery?

Even though most tears cannot heal on their own, good function can often be achieved without surgery. If, however, you are active and use your arm for overhead work or sports, then surgery is most often recommended because many tears will not heal without surgery.

What does the gastrocnemius and soleus do?

Function. Along with the soleus muscle, the gastrocnemius forms half of the calf muscle. Its function is plantar flexing the foot at the ankle joint and flexing the leg at the knee joint.

Why is the latissimus dorsi muscle important?

The latissimus dorsi muscle is a large, triangularly shaped back muscle that helps you do things like pull-ups, swimming and even breathing. It functions to stabilize your back while extending your shoulders.

What does the pectoralis major do?

The pectoralis major extends across the upper part of the chest and is attached to a ridge at the rear of the humerus (the bone of the upper arm). Its major actions are adduction, or depression, of the arm (in opposition to the action of the deltoideus muscle) and rotation of the arm forward about the axis of the body.

How long does an Infraspinatus to heal?

Recovery from a small tear or tendinitis can take between 2 and 4 weeks, or sometimes a few months. Younger people are more likely to heal completely from rotator cuff injuries.

How should I sleep with Infraspinatus pain?

1. Sit in a reclined position. You may find sleeping in a reclined position more comfortable than lying flat on your back. …
2. Lie flat on your back with your injured arm propped up with a pillow. Using a pillow may help reduce stress and pressure on your injured side.
3. Lie on your uninjured side.

Where is supraspinatus pain felt?

Supraspinatus pain is felt at the side of the shoulder in the middle section of the deltoid. In some cases, it can be felt further round the front of the shoulder.