Shoulder pain is quite common in our society. Causes of pain are generally a result from inflammation. The most common cause of inflammation in the shoulder is joint dysfunction and/or muscle imbalance. Other causes are acute trauma (accident, fall, lifting, etc.) repetitive trauma ( doing an activity over and over again, i.e. pitcher in baseball), an old injury that did not heal correctly, and/or poor posture. Some injuries to the shoulder may require surgery. However, most cases of shoulder pain do not.