The shoulder is made up of several joints that combine with muscles and tendons to allow a wide range of arm motion—from throwing the perfect pitch to scratching the back. However, sometimes, mobility has a price. In certain instances, it may result in causing problems with the impingement of the bony structures or the soft tissues in the shoulders, causing pain. Pain might be felt all the time or only when the shoulder is moved. The pain can be temporary or might linger and require medical treatment.
The shoulder is made up of 3 bones—Humerus (upper arm bone), Scapula (shoulder blade), and Clavicle (collar bone). The head of the upper arm bone fits into the rounded socket in the shoulder blade. The socket is called the glenoid. A combination of tendons and muscles keeps the arm bone centered in the shoulder socket. The tissues are known as the rotator cuff. They cover the head of the upper arm bone and attaches it to the shoulder blade.
Most problems related to the shoulder fall into 4 categories:
- Tendon tear or Inflammation
Other less common causes of shoulder pain include:
- Nerve-related problems
The cord that connects the muscle to the bone is called the tendon. When the tendon wears down, it can result to tendinitis, a condition that develops gradually. Generally, there are two types of tendinitis:
- Acute – explosive ball throwing and performing overhead activities during sport or work may result to acute tendinitis.
- Chronic – repetitive wear and tear secondary to age and degenerative diseases like arthritis may lead to chronic tendinitis.
Commonly affected tendons in the shoulder include one of the bicep tendons and the four rotator cuff tendons. The rotator cuff provides shoulder stability and shoulder motion.
The small, fluid-filled sacs situated in the joints throughout the body (including the shoulder) are called the bursae. They also act as cushion between the overlying soft tissues and the bones and help minimize the friction between the bone and the gliding muscles. In some instances, excessive use of the shoulder can result to the swelling and inflammation of the bursa between the part of the shoulder blade called the acromion and the rotator cuff. The condition is called subacromial bursitis. In many cases, bursitis occurs in association with rotator cuff tendinitis.
When the acromion (top of the shoulder blade) puts pressure on the underlying soft tissues (when lifting the arm away from the body), shoulder impingement develops. In addition, bone spurs (syndesmophytes) may grow and press against the tendon. When the arm is lifted, the acromion “impinges” or rubs on the bursa and the rotator cuff. This can lead to tendinitis or bursitis and can cause limited movement and pain. Severe cases of impingement can sometimes lead to rotator cuff tear.
When the upper arm bone’s head is forced out of the shoulder socket, shoulder instability or frank dislocation occurs. The condition can result from overuse or sudden injury. Shoulder dislocations can be partial or complete. Partial dislocation occurs when the ball of the upper arm comes out of the socket just partially. This condition is also called subluxation. When the ball comes all the way out of the socket, a complete dislocation occurs.
Shoulder pain can also be attributed to arthritis. Osteoarthritis is the most common type of arthritis that affects the shoulder. It is also known as “wear and tear” arthritis. Symptoms of the condition include stiffness, swelling, and pain. Osteoarthritis can develop gradually and the pain can worsen over time. The condition can be related to chronic wear and tear and sports or work related injuries. Other types of arthritis are also related to infection, inflammation of the joint lining, and rotator cuff tears.
If an acute injury causes severe shoulder pain, seeking immediate medical attention is advised. If the pain is not severe, resting for a few days to see if the problem will resolve on its own is suggested. However, if symptoms will persist, seeing an orthopaedic specialist is recommended. To accurately diagnose the cause of the shoulder pain and to identify the best treatment intervention, a thorough evaluation will be conducted.
Medical History – The doctor will ask when and how the pain started and other questions to help gauge the patient’s general health and identify possible causes of the shoulder pain.
Physical Examination – To find the cause of the shoulder pain, a thorough physical examination has to be conducted. The doctor will check for swelling, muscle weakness, deformities, and other physical abnormalities. The shoulder strength and range of motion will also be checked.
Tests – Specific tests may also be ordered to help accurately identify the specific cause of the pain. Some of the tests can include:
- Computed Tomography (CT) Scan
- Ultrasound and Magnetic Resonance Imaging (MRI)
- Electrical Studies
Activity Changes – To help improve shoulder flexibility and strength, rest, physical therapy, and altering activities will be suggested.
Medications – Medications might be prescribed to reduce pain and inflammation. Depending on the severity, injections may also be recommended.
Surgery – Ninety percent of cases of shoulder pain will often respond to conservative treatment methods like exercise, rest, activity changes, and medication. However, surgery might be required to resolve other cases. For instance, surgery might be recommended in certain shoulder problems like rotator cuff tears and recurring dislocations. Surgery can involve open procedures for shoulder replacement or larger reconstructions or it can involve arthroscopy to repair torn tissues or remove scar tissue.