When the tendons of the rotator cuff and the surrounding bursa become inflamed, the painful and disabling condition is called shoulder impingement. This occurs in a tiny space between the tip of he humerus or arm bone and the top of the shoulder blade or scapula.
A bursa or lubricating sac surrounds and protects the tendons of several structures and can swell up due to overuse and make the space narrower. This narrowing further irritates the tendons and bursa, causing more inflammation.
Pretty soon, movement of the shoulder joint becomes limited due to pain and you have a full blown case of shoulder impingement.
Typically, actions that cause this condition are frequent high speed extension of the arms such as pitching a baseball, window washing, painting, hanging wallpaper or drapes, or any other activity with similar movements.
Rest is the first recommendation, since repeating the movement that created the condition will only worsen the inflammation. Localized ice massage is an effective way to reduce pain and swelling.
Doctors may use non-steroidal anti-inflammatory medications or even steroid injections. Physical therapists will use ultrasound therapy and perhaps a sling to temporarily immobilize the joint.
As the swelling subsides, exercise will be incorporated to strengthen the shoulder muscles and to restore range of motion. If conservative therapy is not beneficial, surgery may be required.