Q: My 15-year-old son injured his shoulder playing baseball. The doctor said he had a rotator cuff injury. He told him to rest the shoulder for two weeks and then resume his normal activities. After four weeks it is still painful for him to lift his arm or carry heavy things. Is there anything else we should do? Is it OK for him to use the arm, even if it hurts?
A: This question is complicated. The shoulder is a complex area that actually has three joints and not just one. The sockets are quite shallow and the muscles are really all that hold the joints in place.
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The rotator cuff is comprised of a group of four muscles that are used to lift your arm over your head and rotate it toward and away from the body. The most important muscle is called the supraspinatus, which is located along the top of the shoulder blade. Baseball is a common activity that causes injuries to these muscles.
Rotator cuff problems can be divided into three categories. Rotator cuff tendonitis, sometimes called impingement syndrome or shoulder bursitis, usually occurs in people over 30, so it is unlikely that your son has it. The symptoms are pain when moving the joint and the pain is worse at night.
Treatment may include anti-inflammatory medications and cortisone injections.
Instability impingement occurs in younger people, 15-30, which would include your son. This leads to a rubbing or clicking of the shoulder in an overhead movement, which is caused by the ball of the joint rubbing against the bony ledge, called the acromium. The treatments are the same as the previous condition, but in resistant cases surgery may be required to shave a little bone off the acromium.
Finally, a rotator cuff tear usually happens to people who have had tendonitis for a while, and the joint has become weak and unstable. It can happen suddenly if the person tries to lift something too heavy and feels a pop in the shoulder. There is acute and sudden pain, and the patient is unable to raise the shoulder. Most cases improve with rest and anti-inflammatory medications. A strong painkiller may be needed for the first few days.
The doctor is correct in saying that your son should resume his normal activities as soon as possible. Resting the joint for more than a couple of weeks will just lead to further weakness and deterioration of the surrounding muscles. I would recommend he avoid really heavy lifting until he has worked up to it gradually. A physiotherapist can recommend an exercise program to gradually build up strength in the shoulder.
If there is no improvement after a couple of months, your son may need to have an MRI to assess the extent of the injury in case surgery is needed.