The most common cause of shoulder tendonitis is repeated microtrauma to the rotator cuff tendons rather than a specific one-off trauma. Rotator cuff tendonitis is a common source of pain in the shoulder and is common in both young athletes and middle-aged people. Young athletes who use their arms in overhead motions for swimming, baseball, and tennis are particularly vulnerable. Those who do repetitive lifting or overhead activities using the arm, such as paper hanging, construction, or painting are also susceptible.
Four separate muscles make up the rotator cuff group in the shoulder. Rotator cuff pain commonly causes local swelling and tenderness in the front of the shoulder. Pain and stiffness are common when lifting your arm. Over time, these repetitive rotator cuff injuries can lead to degenerative changes and even lead to rupture or tearing of the muscle or tendon.
Shoulder tendonitis commonly has the following symptoms:
- Shoulder clicking when the arm is about shoulder height.
- Shoulder and upper arm pain.
- Shoulder pain when lifting with a straight arm.
- Shoulder pain or clicking when you place your hand behind your back or head.
Bursae are small, fluid-filled sacs that are located in joints throughout the body, including the shoulder. They act as cushions between bones and the overlying soft tissues and help reduce friction between the gliding muscles and the bone. Your subacromial bursa is the most commonly inflamed of the shoulder bursa. Subacromial bursitis is a common cause of shoulder pain that is usually related to shoulder impingement of your bursa between your rotator cuff tendons and bone (acromion).
Sometimes, excessive use of the shoulder leads to inflammation and swelling of the bursa between the rotator cuff and part of the shoulder blade known as the acromion. The result is a condition known as subacromial bursitis. Bursitis often occurs in association with rotator cuff tendinitis. The many tissues in the shoulder can become inflamed and painful. Many daily activities, such as combing your hair or getting dressed, may become difficult.
- Pain on the outside of your shoulder, into the upper arm.
- Pain that is made worse when lying on your affected shoulder
- Pain that is made worse when using your arm above your head.
- Shoulder pain with washing hair, dressing, or tucking in your shirt.
Shoulder Impingement Syndrome
Impingement syndrome occurs when there is inflammation between the top of the humerus (arm bone) and the acromion (tip of the shoulder blade). Between these bones are the tendons of the rotator cuff and the bursa that protects these tendons.
Normally, these tendons slide effortlessly within this space called the subacromial space. In some people, this space becomes too narrow for normal tendon motion, and the tendons and bursa become inflamed. Inflammation leads to thickening of the tendons and bursa, and it also contributes to the lack of adequate room in the subacromial space. Eventually, this space becomes too narrow to accommodate the tendons and the bursa, and every time these structures move between the bones they are pinched.
- Pain, weakness, and a loss of movement of the affected shoulder.
- Pain that is worsened by shoulder overhead movements.
- Pain that is worse with lying on the affected shoulder.
- Sharp pain with lifting that radiates into the arm.
Rotator Cuff Tear
A rotator cuff injury can make it painful to lift your arm out to the side. When one or more of the rotator cuff tendons is torn, the tendon no longer fully attaches to the head of the humerus. Most tears occur in the supraspinatus muscle and tendon, but other parts of the rotator cuff may also be involved.
There are 2main different types of tears:
Acute Tear – If you fall down on your outstretched arm or lift something too heavy with a jerking motion, you can tear your rotator cuff. This type of tear can occur with other shoulder injuries, such as a broken collarbone or dislocated shoulder.
Degenerative Tear – Most tears are the result of a wearing down of the tendon that occurs slowly over time. This degeneration naturally occurs as we age. Rotator cuff tears are more common in the dominant arm. If you have a degenerative tear in one shoulder, there is a greater risk for a rotator cuff tear in the opposite shoulder — even if you have no pain in that shoulder.
The most common symptoms of a rotator cuff tear include:
- Pain at rest and at night, particularly if lying on the affected shoulder.
- Pain when lifting and lowering your arm or with specific movements.
- Weakness when lifting or rotating your arm.
- Crepitus or crackling sensation when moving your shoulder.
Bicipital Tendon Injury
The biceps muscle is in the front of your upper arm and helps you bend your elbow and rotate your arm. Your biceps tendons attach the biceps muscle to bones in the shoulder and in the elbow. If you tear the biceps tendon at the shoulder, you may lose some strength in your arm and be unable to forcefully turn your arm from palm down to palm up.
Many people can still function with a biceps tendon tear, and only need simple treatments to relieve symptoms. Some people require surgery to repair the torn tendon. Biceps tendon tears can be either partial or complete. A complete tear means the total loss of connection of the long head at its attachment point in the glenoid. Partial tears do not completely sever the tendon.
- Sharp pain at the shoulder or elbow.
- A bruise that appears on the upper arm.
- A feeling of weakness in the shoulder or elbow.
- Trouble rotating your arm from “palm up” to a “palm down” position.
SLAP Tear/Labrum Injury
A SLAP tear is an injury to the labrum of the shoulder, which is the ring of cartilage that surrounds the socket of the shoulder joint. The term SLAP stands for Superior Labrum Anterior and Posterior. In a SLAP injury, the top (superior) part of the labrum is injured. This top area is also where the biceps tendon attaches to the labrum. A SLAP tear occurs both in front (anterior) and back (posterior) of this attachment point. The biceps tendon can be involved in the injury, as well.
Injuries to the superior labrum can be caused by acute trauma or by repetitive shoulder motion. Many SLAP tears, however, are the result of a wearing down of the labrum that occurs slowly over time. In patients over 40 years of age, tearing or fraying of the superior labrum can be seen as a normal process of aging.
- A sensation of shoulder locking, popping, catching, or grinding.
- Pain with movement of the shoulder.
- Pain with lifting objects, especially overhead.
- A feeling that the shoulder is going to “pop out of joint.”