Ways to Diagnose a Rotator Cuff Tear

Your rotator cuff is a combination of muscles and tendons that form a protective covering around the humerus, or the top of the arm bone. With a chief function to allow the arm to rotate and move freely, the tear can slowly develop over time or can occur due to injury. A rotator cuff tear is diagnosed through a number of tests, such as a physical examination and X-rays or other imaging studies.

Symptom History

• When meeting with a doctor, he \will first ask you to describe your symptoms. Typical symptoms include pain while lifting the arm, weakness in the arm, cracking noises when the arm is moved or muscle atrophy around the shoulder.

Physical Examination

• Next, a doctor should test for weakness in the arm by performing three exercises. First, while seated, point the thumb toward the floor and hold the arm out at a 90-degree angle with the other arm held shoulder-level to your side. The doctor will try to push the arm down and measure the amount of resistance you provide.

  While still seated, the arms will be held with the arms bent at the elbows. With the thumbs turned up and the hands rotated in toward each other at a 20-degree angle, the physician will push against the arm while you try to rotate the arm. The physician will measure the amount of weakness in this action.

  Finally, the arm is held out straight, then lifted. If you experience pain while doing this, you may have a rotator cuff tear.

Imaging Studies

• X-rays of the shoulder can show a rotator cuff tear or small spur on the shoulder. If the tear is more difficult to spot, an ultrasound or magnetic resonance imaging scan can allow a physician to better view the tendons in the arm. This often is necessary in order to assess how large the tear is.