The shoulder is a complex joint that allows the largest range of motion of all joints in the body. Left shoulder pain is a common complaint as people age, due to the flexibility of the joint and its constant use. Most incidents of pain involve the soft tissues that provide stability to the shoulder: its tendons, ligaments and muscles. Occasionally the bones that comprise the shoulder are affected as well.
Conditions that cause pain in the left shoulder are often interrelated. For example, tendinitis may either be caused by or experienced as a result of a torn rotator cuff. Typical causes of shoulder pain include arthritis, strains, sprains, dislocations, separations, bursitis, frozen shoulder and fractures.
Radiating Shoulder Pain
Pain in the left shoulder may be caused by unrelated medical issues that stem from a heart attack, In these cases, the pain travels from the heart, through the chest and along the nerves to the left shoulder. Right shoulder pain is more likely a result of unrelated liver or gallbladder disease, but may occur in the left shoulder as well. Left shoulder pain may also be the result of an unrelated neck injury or disease. These issues will be ruled out by a health care provider when initially diagnosing the possible causes of left shoulder pain.
A variety of chronic inflammatory conditions may cause pain in the left shoulder. Bursitis is the inflammation of the shoulder's bursa, a lubricating fluid-filled sac that limits rubbing, friction and irritation between the shoulder bones and tendons. Tendinitis is caused by inflammation of the tendons attaching the shoulder muscles to one of three bones in the shoulder. These conditions may be the result of a chronic condition such as arthritis, chronic repetitive motion or injury. Pain will occur each time you move your left shoulder when one of these conditions is present.
A shoulder dislocation occurs when the ball-shaped head of your arm, the humerus bone is removed from the shoulder socket. It usually occurs as a result of a sports injury or a fall. With dislocation, there is damage to the ligaments connecting the shoulder blade to the collarbone. Either type of related damage causes pain when trying to lift the affected arm. If left untreated, this condition will lead to restricted range of motion.
Rotator Cuff Injury
The rotator cuff, comprised of a network of several tendons and muscles around the top of the humerus, holds the humerus in place and is what allows you to lift and rotate your arm as well as reach over your head. Damage to the rotator cuff is not only painful, but may weaken the shoulder muscles and limit the shoulder function necessary to perform these actions. Rotator cuff tears may occur as a result of a single traumatic injury, wear and tear with ageing, or repetitive overhead motions from participating in sports such as tennis, baseball, weightlifting and rowing.