How to prevent it: Exercise your rotator cuff muscles to keep them strong and improve your range of motion. Be careful when you play sports like golf and tennis that use the same repetitive motions. Switch up your game once in a while. And stop whenever you feel pain.
AC Joint Injury
What it is: The AC (acromioclavicular) joint is located where the uppermost part of your shoulder blade -- a structure called the acromion -- meets your collarbone. When ligaments connecting the acromion and collarbone get torn, you've got a separated shoulder.
How it can get injured: Getting hit hard in the shoulder or falling on an outstretched hand can cause a separated shoulder.
What you'll feel: Pain in your shoulder. You might also see a bump on top of the shoulder where it's separated.
How it's treated: Wear a sling to keep your shoulder still. Ice the area for about 20-30 minutes every couple of hours to reduce swelling. Take acetaminophen or a nonsteroidal anti-inflammatory drug like ibuprofen to help with the pain.
How to prevent it: Do range-of-motion and strengthening exercises. Gradually increase the weight and number of reps to strengthen your shoulder.
What it is: A dislocated shoulder happens when the top of the upper arm bone (the ball) slips out of its socket. The ball can slip forward, backward, or downward. Before you fully dislocate it, the shoulder might feel like it's starting to go out of place. That's called instability. When the shoulder slips only partway out of the socket, it's a subluxation.
How it can get injured: A strong hit to your shoulder on the football field or ice hockey rink can pop the ball out of its socket. You can also get a dislocated shoulder if you rotate your shoulder joint too far, like when you're serving in volleyball.
What you'll feel: You can feel when your shoulder pops out of place. The pop will be followed by intense pain. You might also have swelling, bruising, and weakness in the arm.
How it's treated: Sometimes a coach or friend can pull a dislocated shoulder back into place, but don't let anyone work on your shoulder unless you're sure they know what they're doing. Otherwise, you could end up with an even worse injury. Instead see a health care provider, who will give you a sedative or pain medicine before sliding your upper arm bone gently back into its socket. You'll have to keep the shoulder still for a few weeks afterward in a sling.
If the shoulder is being stubborn and it won't go back in place, you can have surgery to relocate the joint. Surgery can also repair torn ligaments or tendons in your shoulder.
How to prevent it: Once you've fully healed, start exercising your shoulder to keep it flexible. Slowly add in weights and resistance bands to increase shoulder strength. If your shoulder has been dislocated before, ease off on the sports until it heals. That can take a few weeks. Anyone who's had a dislocation once has a good chance of it happening again. When you do start playing contact sports again, wear shoulder pads or other protective gear.