The rotator cuff muscles and tendons hold your upper arm bone in your shoulder socket. A hard fall, repetitive arm motions or problems with the structure of your shoulder can injure the rotator cuff.
Trauma and Overuse
A sudden tear in the rotator cuff can be caused by a traumatic fall, or by lifting a heavy weight incorrectly. Tears can also develop gradually. Repetitive arm motions – especially overhead motions common in sports such as tennis and baseball – can place great stress on your muscles and tendons. Certain muscles may begin to overpower others. This muscle imbalance can lead to shoulder instability, which can result in a tear.
In some shoulders, there is not enough space between the rotator cuff and the acromion (a bony projection of your shoulder blade). This lack of space can be caused by a poorly-shaped acromion. It can be caused by the growth of bone spurs, or by swelling in the joint. Lifting the arm can cause the acromion to pinch a rotator cuff tendon. This is called shoulder impingement. Over time, it can lead to rotator cuff tears.
Aging also raises your risk for a tear. As you age, the blood supply to your shoulder begins to decrease. Your shoulder has a more difficult time repairing itself after minor injuries. Tendons and muscles can gradually become damaged with the normal stress of everyday use. This can allow tears to happen more easily.
Rotator cuff injuries typically cause pain in your shoulder, even when you are at rest. The pain typically increases when you lift your arm. You may hear a grinding or a popping sound when you move your arm. Your arm may feel weak. If you have a severe rotator cuff tear, you may not be able to lift your arm at all.
Treatment options depend on the severity of your injury. You may benefit from rest and medications. Your healthcare provider may recommend injections or physical therapy. If those methods are not effective, surgery may be needed.