This condition refers to inflammation in the space between the acromion, or tip of the shoulder blade, and head of your humerus where your rotator cuff tendons attach. When you raise your arm to shoulder height, the space between the acromion and rotator cuff narrows. The acromion can rub against, or "impinge" on, the tendon and/or the bursa, causing irritation and pain to one or both of these structures. Typically an individual with this problem will have pain and stiffness when lifting the arm, especially in mid-top of the range. There may also be pain when the arm is lowered from an elevated position. It will commonly progress and worsen over a period of months and motion, strength, and activity tolerance will steadily decrease.
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