The rotator cuff is a group of four muscles that surround the humeral head (ball of joint). The muscles are referred to as the “SITS” muscles-Supraspinatus, Infraspinatus, Teres minor and Subcapularis. The muscles function to provide rotation and elevate the arm and give stability to the shoulder joint (glenohumeral joint). The supraspinatus is most frequently involved in degenerative tears of the rotator cuff. More than one tendon can be involved. There is a bursa (sac) between the rotator cuff and acromion that allows the muscles to glide freely when moving. When rotator cuff tendons are injured or damaged, this bursa often becomes inflamed and painful.
Rotator Cuff Tendonitis
Rotator cuff tendinitis is an inflammation (irritation and swelling) of any of the 4 tendons of the rotator cuff muscles of the shoulder. The most common ones injured are supraspinatus and infraspinatus. Often the patient can develop what is known as “impingement syndrome”.
Repeated movement of the arm overhead can cause the rotator cuff to contact the outer end of the shoulder blade where the collarbone is attached, called the acromion. When this happens, the rotator cuff becomes inflamed and swollen, a condition called tendonitis. The swollen rotator cuff can get trapped and pinched under the acromion. All these conditions can inflame the bursa in the shoulder area. A bursa is a fluid-filled sac that provides a cushion between a bone and tissues such as skin, ligaments, tendons, and muscles. An inflammation of the bursa is called bursitis
Causes, incidence, and risk factors
The shoulder joint is a ball and socket type joint where the top part of the arm bone (humerus) forms a joint with the shoulder blade (scapula). The rotator cuff holds the head of the humerus into the scapula and secures the joint.
Inflammation of the tendons of the shoulder muscles can occur in sports requiring the arm to be moved over the head repeatedly as in tennis, baseball (particularly pitching), swimming, and lifting weights over the head. Chronic inflammation or injury can cause the tendons of the rotator cuff to tear.
The risk factors are being over age 40 and participation in sports or exercise that involves repetitive arm motion over the head (such as baseball).
- Pain associated with arm movement; mainly overhead activities
- Pain in the shoulder at night, especially when lying on the affected shoulder
- Weakness with raising the arm above the head, or pain with overhead activities (brushing hair, reaching for objects on shelves, etc.)
Rotator Cuff Tears
Rotator cuff tears are a common source of shoulder pain. . The incidence of rotator cuff damage increases with age and is most frequently due to degeneration of the tendon, rather than injury from sports or trauma. Rotator cuff tears increase in frequency with age, are more common in the dominant arm, and can be present in the opposite shoulder even if there is no pain. The highest incidence occurred in patients who were more than 60 years old.
Causes, incidence, and risk factors
There are intrinsic and extrinsic causes of rotator cuff tears. An example of an intrinsic factor is tendon blood supply. The blood supply to the rotator cuff diminishes with age and transiently with certain motions and activities. The diminished blood supply may contribute to tendon degeneration and complete tearing. The substance of the tendon itself degenerates over time. Due to an age related decrease in tendon blood supply, the body’s ability to repair tendon damage is decreased with age; this can ultimately lead to a full-thickness tear of the rotator cuff.
An extrinsic cause would be damage to the rotator cuff from bones spurs underneath the acromion. The spurs rub on the tendon when the arm is elevated; this is often referred to as impingement syndrome. Bone spurs are another result of the aging process. The rubbing of the tendon on the bone spur can lead to attrition (weakening) of the tendon. Combining this with a diminished blood supply, the tendons have a limited ability to heal themselves
Treatment for Rotator Cuff Injuries
The injured shoulder should be rested from the activities that caused the problem and from activities that cause pain. Ice packs applied to the shoulder and non-steroidal anti-inflammatory drugs will help reduce inflammation and pain. Laser therapy and acupuncture are also great tools which can be used to reduce inflammation and pain. Muscle release techniques are also important to reduce stiffness around the joint and the spine.
Therapy to strengthen the muscles of the rotator cuff and the scapula should be started; attention to any causative factors such as poor posture should also be addressed. This is especially important because if left untreated frozen shoulder can set in which is a very painful and chronic condition.
For more information please contact Mississauga Chiropractor Dr. Nekessa Remy at email@example.com