Shoulder impingement

Shoulder impingement is becoming increasingly common. The term literally means “shoulder collision,” but in everyday language it is better described as “shoulder impingement” or “shoulder pinching.” It often causes pain when lifting the arm.

The shoulder consists of a shoulder blade that extends over the head of the upper arm, forming the “shoulder roof.” Between the shoulder roof and the head of the humerus is a narrow space through which various structures run, such as bones, muscles, tendons, bursae and joint capsule.

In the case of shoulder impingement, the space between the humeral head and the shoulder roof becomes reduced. This narrowing causes structures in that space to become pinched during movement. This can be painful, especially when lifting the arm. Many people experience sharp pain when the arm reaches an angle of around 90 degrees.