There are multiple causes of shoulder pain. The pain can stem from injury or disease of the three bones that make-up the shoulder joint (humerus, scapula and clavicle) or it can be due to problems with the numerous joints, muscles and tendons in the shoulder region. Some health conditions – such as gallbladder disease – can cause pain in the shoulder area.
Three bones come together to make the shoulder. The humerus (the upper arm bone), the scapula (shoulder blade) and the clavicle (collar bone). The rounded head of the humerus fits into the glenoid socket, a cup-like socket located in the shoulder blade. The muscles and tendons that keep the humerus in place within the socket are known as the rotator cuff. These support tissues connect the humerus head to the shoulder blade.
Causes of shoulder pain
There are many reasons an individual might experience pain in the shoulder region, but most shoulder pain is due to the following:
- Fractures – sometimes called broken bones, fractures can occur in any of the three bones that make up the shoulder. These breaks can occur as a result of a fall or a high- impact injury. Fractures should be evaluated by a physician since complicated breaks could involve dislocation or even issues requiring surgical repair
- Tendon inflammation or damage – these problems range from tears in the tendon, to inflammation of the bursa (fluid filled sacs that cushion the joint), acute or degenerative changes to the tendon or tendon tears. Sometimes movement of the shoulder blade puts pressure on the rotator cuff making it painful or difficult to lift the arm. This condition is known as impingement
- Arthritis – both osteoarthritis and rheumatoid arthritis can affect any joint in the body. Osteoarthritis of the shoulder is common due to chronic wear and tear of the shoulder joint
- Injury or overuse resulting in joint instability – torn or damaged ligaments, tendons and muscles of the shoulder can cause the joint to become loose and prone to injury or dislocation
Diagnosing shoulder pain
Sometimes shoulder pain develops overtime, such as in the case of overuse injuries or arthritis. Other times, the pain occurs suddenly. Information about the pain including: severity, onset, related injuries, and factors that cause pain to increase or decrease is helpful to your doctor in determining possible causes.
Your physician will also conduct a physical examination to identify any swelling, redness, weakness, tenderness or deformity and to evaluate range of motion.
If tests are needed to pinpoint the source of pain and extent of injury, they may include:
- X-rays – radiographic images of the shoulder joint where the three bones come together. An arthrogram, x-ray done with dye injected into the shoulder joint – can be helpful in identifying muscle, tendon or joint injuries
- MRI – magnetic resonance imaging can be helpful in identifying soft tissue or rotator cuff tendon tears
- Ultrasound – can identify fluid around the joint as well as injury to the tendons and muscles and impingement syndrome
- Nerve conduction studies – done to evaluate nerve function and pinpoint pressure on the nerve or nerve irritation
- Arthroscopy – a minimally invasive surgical procedure that allows your physician to view the inside of the shoulder joint. Some repairs can be performed during arthroscopy
Shoulder pain treatment
Minor shoulder pain can often be relieved by ice (applied intermittently for 15 minutes), rest of the affected shoulder and over-the- counter pain relievers. Care should be taken to avoid any movement that causes pain to increase or worsen.
Other shoulder pain treatment therapies include:
- Physical therapy to build strength and increase flexibility
- Injectable medications given directly into the shoulder. These include steroids and local anesthetics
- Surgery is rarely required for shoulder pain but may be necessary in extreme cases such as severe tears, scar tissue removal or shoulder joint replacement