Rotator cuff tear

Definitions & Key takeaways

A rotator cuff tear occurs when one or more tendons of the SITS muscles - Supraspinatus, Infraspinatus, Teres minor, and Subscapularis - of the rotator cuff are torn. Acute tears happen when the tendons are violently stretched, like falling on an outstretched arm. Chronic tears result from cumulative wear and tear of the tendon, and it usually occurs in the elderly.

The cuff is responsible for stabilizing the glenohumeral joint, abducting, externally rotating, and internally rotating the humerus. When shoulder trauma occurs, these functions can be compromised. The diagnosis is clinical, mainly based on pain and weakness, specifically with abduction or rotation, and can be confirmed with an MRI. Treatment involves rest, ice, and pain control, but if it fails, surgery may be needed.

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Introduction0:00–0:19

The rotator cuff refers to a group of four muscles and their tendons, which help to stabilize the shoulder when it’s moving particularly during rotational motion.
So, a rotator cuff tear is when one or more of the tendons of the muscles of the rotator cuff are torn.The shoulder is a complex of bones, ligaments, muscles and their tendons that all work together to connect the upper limb to the chest, allowing necessary movement and providing stability.The round head of the humerus fits and rotates inside the shallow glenoid cavity of the scapula.

Anatomy0:19–1:56

Just above the glenoid cavity, the scapula extends two bony processes; the acromion and the coracoid processes which serve as attachment for ligaments and muscle tendons.The ligaments of the capsule of the glenohumeral joint hold the head of the humerus inside the glenoid cavity.
The coracoacromial ligament forms an arch between the coracoid process and the acromion and it prevents the head of the humerus from upward dislocation.In addition to these ligaments, the shoulder is supported by the four rotator cuff muscles, also called the SITS muscles, for Supraspinatus, Infraspinatus, Teres minor, and Subscapularis.The SITS muscles form a cuff that surrounds the head of the humerus to make it stable and help it move, specifically in abduction, as well as internal and external rotation.
Below the acromion lies the acromial bursa, which is a small sac filled with rubbery synovial fluid, that provides lubrication and prevents the rotator cuff tendons, especially the supraspinatus tendon, from rubbing against the acromion as the joint moves.A rotator cuff tear may occur when the tendons are violently stretched like when you jerkily lift up something which is too heavy, or accidentally fall on an outstretched arm.

Pathology1:56–3:21

This most commonly affects the supraspinatus tendon at its insertion on the greater tubercle of the head of the humerus, because it’s under a lot of tension when the shoulder is abducted.Now, the tears may be partial, which is where the tendon is damaged but not completely torn, and may even go unnoticed.
Alternatively, the tear may be a full thickness tear, where the tendon is completely detached from the humerus.In contrast to an acute tear, there may also be a chronic tear due to regular wear and tear, which usually occurs in the elderly.
That’s because the blood supply to the rotator cuff tendons reduces over time making it harder for them to heal after an injury.
As a result, injuries can go unrepaired, and successive injuries can weaken the tendon. A classic example is when the shoulder is used to repeat the same motion over and over, like for a pitcher in baseball.Chronic tears can also occur where the bones overgrow, specifically where there may be a bone spur coming off of the acromion that rubs the rotator cuff tendons during shoulder abduction.
This condition is called shoulder impingement.In an acute tear, there can be intense shoulder and upper arm pain, whereas in a chronic tear, the pain might be absent, or only occur when using the affected shoulder.

Symptoms3:21–3:38

The affected shoulder may also be weak, specifically with abduction or rotation.The diagnosis of a rotator cuff tear mainly relies on testing the arm’s range of motion and strength and any associated pain.

Diagnosis3:38–4:04

An X-ray may identify the presence of abnormal bone spurs on the acromion, or if the space between the head of the humerus and the acromion is narrowed.
An MRI can visualize the torn tendon and identify if it’s a partial or complete tear.The treatment of a rotator cuff tear begins with ice to reduce inflammation, pain medication, and rest, with gentle physical exercise to prevent stiffening.

Treatment4:04–4:22

In more severe cases, open or arthroscopic surgery may be needed to repair the torn tendon.Allright, as a quick recap...

Review4:22–5:04

in rotator cuff tears, one or more tendons of the SITS muscles - Supraspinatus, Infraspinatus, Teres minor, and Subscapularis - of the rotator cuff are torn.
Acute tears happen when the tendons are violently stretched, like falling on an outstretched arm. Chronic tears result from cumulative wear and tear of the tendon, and it usually occurs in the elderly.
The diagnosis basically is mainly based on pain and weakness, specifically with abduction or rotation, and can be confirmed with an MRI.
Treatment involves rest, ice, and pain control, but if it fails,