The most common cause for bone spurs is osteoarthritis, or arthritis from wear and tear in the joint. As this condition breaks down the cartilage serving as a cushion at the ends of the bones, the body responds by building bone spurs near the affected area, notes Mayo Clinic.
While the purpose for the bone spurs is not clear, having the extra bone in place may boost the amount of surface area available to help bear loads. People who use their rotator cuff -- a group of tendons and muscles that assist with managing shoulder motion -- to excess, such as pitchers in baseball and quarterbacks in football, may develop the spurs. When the spurs grind against the rotator cuff, the results can include swelling and even tearing, as stated by Mayo Clinic.
People who experience difficulty moving their shoulders, and swelling or pain in the shoulder should seek medical attention. Exact treatment protocols vary, but one common treatment for shoulder bone spurs that do not respond to pain medication, stretching and ice is the surgical removal of spurs that have formed beneath the shoulder's point. Unless the spurs cause pain or limit function, though, they generally do not require treatment, according to Mayo Clinic.