The shoulder is a ball and socket joint made up of the scapula (shoulder blade), clavicle (collarbone), and humerus (upper arm bone). The scapula forms the socket while the head of the humerus forms the ball, enabling full range of motion for the arm.
A group of four tendons and muscles called the rotator cuff maintain stability of the shoulder joint, preventing the humerus from sliding out of the socket bone (dislocation). The rotator cuff attaches the humerus to the shoulder blade and helps to lift and rotate your arm.
Rotator cuff tears can occur suddenly or gradually. When the rotator cuff is torn, pain, weakness and altered range of motion can result.
Trauma, degeneration and aging can cause the rotator cuff to tear. A Rotator cuff tear is a common cause of shoulder pain and weakness in middle-aged and elderly people. However, it can occur at any age from injury.
Rotator cuff tears commonly occur from the following:
- Falling forward on an outstretched hand
- Lifting or pulling a heavy object
- Repetitive actions, especially those involving overhead hand movements such as swimming and tennis
- Bone spurs, an overgrowth of the shoulder bone
- Age: Degenerative changes over time can lead to a rotator cuff tear.
Rotator cuff tears cause pain in the shoulder with swelling, weakness, tenderness and altered range of motion.
Rotator cuff tears can be of two types: partial or complete. With a partial tear, you will experience pain, but will still be able to move your arm. A complete tear involves detachment of the tendon from the humeral head and the inability to move the arm normally.
When you visit your doctor with complaints of shoulder weakness and pain, your doctor analyzes your medical history and performs a thorough examination of your shoulder. Your doctor may order imaging tests such as X-ray’s, MRI or ultrasound to confirm a diagnosis of rotator cuff tear. Sometimes, a shoulder arthrogram is performed, where a dye is injected into the shoulder joint and a series of X-ray images are taken.
Non-surgical treatment of rotator cuff tears is initially recommended to alleviate pain and improve shoulder function. Your doctor may suggest the following measures:
- Rest the shoulder by placing your arm in a sling
- Pain medications
- Physical therapy to teach exercises to increase mobility and strength of the shoulder muscles
- Steroid and local anesthetic injections