“What happens if a rotator cuff is not repaired?”

Nothing.

If you are active you can have ongoing problems if the rotator cuff tear is not treated appropriately. Not all rotator cuff tears, however, require surgery. Surgery should be only done it there is significant pain or limitation of function.

Generally when a tendon (any of the rotator cuff tendons) tears in the shoulder it does not tear in the middle of the tendon but rather tears off of the bone. Tendons are what connects are muscles to bones, so muscle turns to a tendon and then the tendon connects to the bone. So if the tendon tears off of the bone, it still has the muscle attached on the other side. That muscles continues to pull on the tendon and over time the tendon gets further and further away from the bone where it used to attach. Since there is nothing to keep the tendon next to it's attachment on the bone, there is no way for the tendon to heal back down to bone so the only way to address this problem is with surgery. If it is not fixed, the muscle will keep pulling on the tendon until it get approximately 1-2 inches away from where it used to attach (depends on the size of the person) and at that point the muscle will not be able to do anything else (pull any further) and the muscle will just sit there. Over time, since the muscle is not doing anything it will start to wither away (atrophy). The muscle fibers get small and get replaced with fat. Once this process completes, the tendon can no longer be repaired, because even if you repair it and it heals back down to bone, the muscle is not going to be functional anymore. This process is not reversible. Hope this answers your question.

The rotator cuff will not heal by itself. Since you are very young, I recommend an arthroscopic rotator cuff repair.

It depends on many factors including how large the tear is, location and type, as well as mechanism of injury (if any) and physical exam findings. The history and physical are usually more important to determine if surgery is necessary, as opposed to relying solely on an MRI scan. There are many rotator cuff tears that do not require surgery, but the only way to know if you are in this group is to see a good orthopedic shoulder or sports medicine specialist for a thorough work up and examination to determine if you are.

Ron Noy, MD

It will enlarge with time.