Pain in the shoulders can radiate down one or both arms. Often, shoulder pain can be caused by muscle injuries, tendon tears or inflammatory conditions. Longterm functional imbalance can lead to instability, cartilage damage and arthritis. Rarely, pain in the shoulders can be caused by tumors or infection.
Most often the result of rotator cuff tendinitis, bursitis involves inflammation of the bursae, the fluid-filled sacs that provide cushion in the joints. Overuse of the shoulder may also lead to swelling and tenderness of the bursa between the rotator cuff and the outer edge of the shoulder bones (acromion).
Tendons connect muscle to bone, so tendinitis is the result of inflammation in the tendon and can either be classified as acute or chronic. Acute tendinitis in the shoulder can result e.g. from repetitive overhead motion. Chronic tendinitis is caused long-term overuse, wear and tear or arthritic conditions.
Tendon Tears —
Tears can be partial or complete, meaning the tendon is separated from the bone. This may happen suddenly—due to injury—or as the result of overuse (wear and tear). Tendon tears in the arms and shoulders most often occur in the rotator cuff and biceps.
Impingement can lead to bursitis and tendinitis when the tendons of the rotator cuff gets pushed up to the bones of the shoulder (acromion).
Sudden injury or overuse can prompt the upper arm bone to pop out of the shoulder socket, resulting in either a partial or complete dislocation. Once the ligaments and tendons in the shoulder are damaged, dislocations may become a recurring problem, causing instability of the joint with both pain and unsteadiness.
Osteoarthritis is the most common type of arthritis in the shoulder. Typically, it is the result of chronic wear and tear, but sometimes can be caused by sequelae of a structural injury. Swelling, pain and stiffness lead to restricted motion and increased pain over time.
Phantom Limb Pain (PLP) —
Sometimes the brain or spinal cord continues to send pain signals, even though a limb has been removed. Because the pain occurs in an area that is no longer there, treatments involve blocking or altering the signals from the brain or spinal cord.