Calcium is a mineral within our bodies which is present in our blood and in many tissues including bone.
Calcium sometimes settles from the blood stream into areas where is would not usually accumulate and cause problems. One such instance is a condition called acute calcific tendonitis where calcium settles within the rotator cuff tendons of your shoulder, most typically in an isolated area of the tendon. This causes the tendon to become inflamed, leads to impingement, and may cause considerable pain. The condition can come on rapidly or more gradually and often causes extreme pain and considerable shoulder stiffness and dysfunction.