The rotator cuff is made up of four muscles that connect like tendons in the shoulder to form a thick covering at the top of the humerus (shoulder bone). Each muscle originates from the scapula ( scapula ) and connects to the humerus .
The rotator cuff has important functions to stabilize the shoulder, lift and rotate the arm, and ensure that the head of the humerus remains firmly anchored in the humerus.
A total of four muscles make up the rotator cuff:
- Supraspinatus muscle : The supraspinatus muscle originates above the spine of the scapula and joins the large tubercle of the humerus.
- Infraspinous : The infraspinatus muscle originates under the spine of the scapula, in the infraspinatus fossa, and attaches to the posterior part of the greater tuberosity (the part of the bone that attaches to the corresponding muscle) of the humerus.
- Teresa minor : The small round muscle originates from the lateral border of the scapula and attaches to the lower border of the greater tubercle of the humerus.
- Subscapularis muscle : The subscapularis muscle originates on the anterior or anterior surface of the scapula, sits directly on the ribs, and inserts on the lesser tubercle of the humerus .
The abbreviation SITS is often used as a name for the group of muscles that make up the rotator cuff: the supraspinatus, infraspinatus, small circular, and subscapularis.
Each rotator cuff muscle has a specific and important function for the shoulder joint:
- Stabilization of the humeral head at the shoulder joint : V The supraspinatus, infraspinatus, small circular, and subscapularis muscles work together to achieve this goal.
- Abduction or abduction of the shoulder joint to one side : These movements are performed by the supraspinatus muscle.
- Externally, shoulder joint rotation : The infraspinatus and the small round muscle are responsible for this movement.
- Pressure on the head of the humerus : The subscapularis muscle performs this additional function by allowing the humerus to move freely at the shoulder joint during arm raises .
The four muscles of the rotator cuff work together to focus the humerus at the shoulder joint. When you lift your arm, the rotator cuff muscles tighten the joint, stabilizing the shoulder.
Sometimes shoulder pain can occur for no apparent reason. Rotator cuff and shoulder wear can occur due to repetitive stress and poor posture. When this happens, various structures around the rotator cuff can be damaged.
If you have a rotator cuff injury, you may feel pain or weakness when lifting your arm. A rotator cuff injury can make it difficult to perform basic functional activities such as lifting weights, pulling your arms, or sleeping.
Potential injuries and problems with these four rotator cuff muscles can include:
Any of these problems around your shoulder can cause limited movement and function.
But surprisingly, some people have rotator cuff tears, found on magnetic resonance imaging (MRI) , even though they have no pain, loss of strength, or limited function. Having a rotator cuff tear doesn't necessarily mean you have shoulder problems .
Risk factors for rotator cuff injury
There are certain movements and actions that increase the likelihood of a rotator cuff injury. This includes:
- Performing general tasks
- Constant stress on the shoulder joint, such as throws and rackets.
- Contact sport
- Sitting with rounded shoulders
- Inability to maintain good physical shape
Normal rotator cuff wear and aging also increase the risk of injury. Accidents like a car accident or a fall can also damage the rotator cuff.
By working to maintain joint health, avoiding excessive stress on your shoulders and repetitive stress on your shoulders, and maintaining proper posture, you can avoid painful shoulder injuries.
Depending on the severity of the rotator cuff injury, treatment options can range from simple rest and immobilization to surgery.
Because recovery from surgery to repair a torn rotator cuff can be slow, orthopedic surgeons tend to avoid prescribing these procedures, with the exception of younger patients, those with large tears, or older patients who rely heavily on measurement of shoulder function.
When rotator cuff problems are causing shoulder pain, consider visiting your doctor for an examination and accurate diagnosis of your condition. You can use a physical therapist to help you figure out the cause of your shoulder pain and work to restore normal range of motion (ROM) and strength to your shoulder.
Your therapist will ask you questions about your shoulder pain and problem. They can do specific tests on your shoulder to determine which structures are causing pain and mobility problems.
Rotator cuff treatment may involve the use of pain relief therapies, and you will most likely be prescribed shoulder exercises to help restore normal joint mobility. These exercises can include:
Your physical therapist can teach you what to do now to address your rotator cuff problem, and should also show you how to prevent future problems with the SITS muscles.
Consult a physician before beginning any rotator cuff exercise program. Stop doing exercises that cause severe pain or discomfort in your shoulder.
Get the word of drug information
Knowing the four muscles of the rotator cuff and how they work is an important component of understanding shoulder rehabilitation . See your GP for more information on shoulder pain and the rotator cuff muscles that support your shoulder.