Chronic shoulder pain can be difficult to diagnose because the shoulder is a complex structure made up of many different components. Learning shoulder anatomy and symptoms of different types of problems can help you determine what is causing your pain.
The shoulder is made up of a number of bones, muscles and tendons. These work together to keep the arm centered in the shoulder socket and to facilitate motion.
The three main bones of the shoulder are the scapula (shoulder blade), clavicle (collar bone) and humerus (upper arm bone).
The rotator cuff is comprised of 4 muscles (supraspinatus, infraspinatus, teres minor and subscapularis) and their tendons. They work to stabilize and rotate the shoulder. This structure stretches from the top of the humerus to the scapula. More details on the rotator cuff can by found at en.wikipedia.org.
The final component to be aware of is the bursa. Bursa is a fluid-filled sac that reduces friction between bone and soft tissues such as muscles and tendons, allowing the muscle or tendon to glide over the bone smoothly. There is a bursa located in the shoulder between the acromion and the supraspinatus tendon.
Common Causes of Pain
One common shoulder injury is tendinitis. There are 4 rotator cuff tendons in the shoulder, plus a tendon attaching to the biceps muscle. Any of these may begin to wear down from overuse or age. Tendons are more likely to wear in people who conduct regular overhead activities at work or participate in sports like baseball that involve throwing. Due to chronic overuse or acute injury, tendons may tear completely. This may require surgery. Tendinitis is mainly marked by pain and stiffness. When a tendon wears down or tears, it becomes inflamed. This inflammation causes localized pain and decreases range of motion. Standard treatment includes ice, physical therapy, steroid injections and splinting.
Osteoarthritis is another potential cause of shoulder pain. It can affect both the AC and glenohumeral joints. This type of pain usually comes on gradually and affects those of middle age or older. Pain is localized to the affected joint and often accompanied by swelling. Stiffness results both from inflammation and from reduced movement due to pain. Osteoarthritis is a wear and tear type of disease; those who participate in activities that use one or both shoulders such as those mentioned above are at higher risk for osteoarthritis of the shoulders. People with osteoarthritis often need to modify the way they move, but it is always important to keep moving. Shoulder osteoarthritis treatment involves careful exercise therapy to strengthen muscles and tendons that support the joints and to encourage range of motion. See www.uptodate.com for more on shoulder exercises and stretches for osteoarthritis.
Most causes of shoulder pain involve inflammation and stiffness. Paying attention to where the pain is located and how quickly its onset is will help you and your doctor determine the best shoulder pain treatment.