I like to play tennis in adult leagues year-round. Lately it feels like my shoulder is too loose. I need full motion to get a good serve but sometimes it feels like it could just pop right out of the socket. Is there anything I can do about this?

Overhead athletes often have quite a bit of give or laxity in the joint. This is especially true of forward motion of the head of the humerus (upper arm bone) in the shoulder socket. Too much laxity can lead to instability and dislocation.

There are some tests that can be done to check your joint laxity and look for shoulder instability. Some of these tests are performed by the doctor while you are in the office. Others must be done with imaging studies such as MRIs or CT scans.

By putting the shoulder in certain positions, the doctor can test for the strength and integrity of shoulder ligaments, tendons, and the joint capsule. These soft tissue structures are what hold the joint in place while still allowing motion.

Treatment is determined by the amount of laxity present and the underlying cause. When ligaments are too loose, stretched out, or torn, the muscles around the joint can be strengthened. Four main muscles surround the shoulder and form the rotator cuff. If the capsule is torn and/or the tendons of the rotator cuff are damaged, then surgery may be needed.

From your description, it sounds like a mild problem with either joint laxity or minor instability. A rehab program may be the best option, but a medical evaluation is needed first. Once the problem is examined and the cause is determined, then the proper treatment can be applied.