The rotator cuff is a group of tendons and muscles in the shoulder that form a "cuff" over the top end of the arm. The rotator cuff supports the arm at the shoulder joint by keeping the head of the upper arm bone (humerus) firmly within the shoulder socket. It also helps facilitate arm movement (e.g., raising the arm and rotating it) and keeping the shoulder stabilized as the arm moves. The four main muscles in the rotator cuff are:
- supraspinatus,
- infraspinatus,
- subscapularis, and
- teres minor.
Other muscles that help with arm movement and shoulder stabilization include the deltoid, teres major, corachobrachialis, latissimus dorsi and pectoralis major.
What is a rotator cuff tear?
Rotator cuff tears happen in younger people when they experience a trauma such as a fall (typically falling on an outstretched hand) or as a result of gradual wear due to repetitive activities. In middle-aged people and seniors, rotator cuff tears are usually the result of a gradual wearing out of the rotator cuff tendon(s) due to tissue degeneration. The signs and symptoms of rotator cuff tears are pain in the shoulder often radiating down to the middle of the arm especially when the arm is raised overhead, weakness, and in severe cases, a complete loss of the ability to lift the arm. Diagnostic tests sometimes include an arthrogram (a radio-opaque dye is injected into the shoulder, and if it leaks out of the rotator cuff, it can be viewed on x-ray) or an ultrasound, but an M.R.I. of the rotator cuff is the most common test used for diagnosis.
Treatment in young and middle-aged patients is usually arthroscopic or open repair of the torn tendons. In older patients, activity modification, anti-inflammatory medication, physical therapy and cortisone injections are typical. Surgery is a last resort because it is so hard on the body and many seniors may not survive the effects of anesthesia.
