Shoulder instability is a common shoulder condition that tends to appear more in young people who are active in sports or other physical activities, but it can affect anyone. Early, proper management and treatment is important to help reduce pain and inflammation so you can return to your daily activities. The orthopedic shoulder specialists at The Ohio State University Wexner Medical Center in Columbus, Ohio, are experts in diagnosing and treating shoulder instability, offering personalized care to help you get back to living your life without discomfort.
What is shoulder instability?
Shoulder instability occurs when the shoulder joint moves too much or slips out of place, causing pain and difficulty when using your arm.
The shoulder is a complex joint made up of bone, tissue, muscle and cartilage. The shoulder is made up of three primary bones: the upper arm bone (humerus), the shoulder blade (scapula) and the collarbone (clavicle). In cases of shoulder instability, a portion of the upper arm bone (humeral head) and the socket in the scapula (glenoid fossa) move out of place.
The shoulder is a “ball and socket” joint, which means that the upper arm bone has a rounded end that fits into a small, cup-like area in the shoulder blade. This design allows the shoulder to move in many directions, making it one of the most flexible joints in the body.
What’s the difference between shoulder instability and shoulder dislocation?
Shoulder instability usually occurs due to direct injury. The range of injury can be mild to severe, but usually results in:
- Partial subluxation: Where the upper arm bone partially comes out of the socket but doesn’t separate from it.
- Full dislocation: This occurs when the ball (humeral head) comes completely out of the socket (glenoid fossa).
If you dislocate your shoulder, it's very likely you also have a tear in your glenoid labrum, a cartilage bumper that helps stabilize your shoulder joint.
What causes shoulder instability?
There are a few risk factors related to shoulder instability. A risk factor is anything that increases your chances of developing a condition.
Some risk factors for shoulder instability may include:
- Direct or previous injury: If you hurt your shoulder by falling with your arm overhead, this can lead to a partial or a total dislocation.
- Athletic participation: Playing contact sports like football can increase the chance of damage.
- Age: Younger people who play sports or people who are over 40 who dislocate their shoulders often tear their rotator cuff tendons, and this can damage the shoulder joint.
- Other medical conditions: If you have conditions that cause hypermobility or other connective tissue disorders, you’re at greater risk of shoulder instability.
- Anatomy changes: This includes bone changes in the shoulder joint.
As a reminder, just because you may have a risk factor, it doesn’t mean you’ll develop the condition. Talk to your doctor if you have any specific concerns.
Shoulder instability symptoms
There are many associated symptoms of shoulder instability. You may have one or more symptoms.
Some of these may include:
- Lack of strength or feelings of weakness in the shoulder or arm
- Limited range of motion
- Sensation that the shoulder joint is slipping out of place
- Popping or clicking sounds when you move your shoulder
- Pain, including pain that worsens when raising the arm or interferes with activities
If you’re experiencing any unusual symptoms, be sure to talk to your doctor.
Diagnosing shoulder instability
To diagnose shoulder instability, our sports medicine experts will start with a physical exam. They’ll review your symptoms and check to see if your shoulder feels like it's slipping out of place. They will also ask you about your medical history and if there are any recent injuries to the affected area.
After the exam, they may order diagnostic imaging to see any damage to the bones, cartilage and rotator cuff.
If your doctor determines diagnostic imaging is needed, they may order one or more of these tests:
- X-rays
- Magnetic resonance imaging
- Computed tomography scans
Your doctor will use the imaging to help form a diagnosis and treatment plan.
Shoulder instability treatment
The Ohio State Wexner Medical Center shoulder specialists offer a few treatment options for shoulder instability, both nonsurgical and surgical.
You may be fitted with a sling that you will wear for several days to a week or two, followed by physical therapy to strengthen the muscles that stabilize your shoulder.
About 70% of people will not have further shoulder instability. However, males under 25 have over 80% risk of further instability without shoulder surgery, especially if playing contact sports.
If surgery is necessary, minimally invasive arthroscopic surgery is usually successful in stabilizing a shoulder for someone who has a first-time dislocation. This reduces the risk of further instability.
During the surgery, along with a general anesthetic, a nerve block is injected into your shoulder to numb your shoulder and arm and to help reduce postsurgical pain. Your surgeon will make small incisions in your shoulder for the arthroscope, which projects images of your shoulder, and other instruments used to repair any labrum tear, if present. Most arthroscopic procedures are on an outpatient basis and take less than an hour. The length of your shoulder surgery will depend on the extent of repair needed. You should be able to go home the same day.
Your arm will be in a sling for four to six weeks after surgery, and you will work with a physical therapist for several months after the procedure. Full recovery and return to sports usually takes four to six months, depending on the activity and the amount of surgical repair.
You and your physician should weigh the risks and benefits of the treatment options as well as your lifestyle goals and preferences. Factors to consider include:
- Risk of recurrence
- Time in a sling with restricted arm motion
- Out-of-pocket cost
- Time away from sporting activities, particularly for in-season athletes
- Risks from anesthesia and surgery
For some people, their shoulder instability damage requires more advanced arthroscopic procedures or even open surgeries that perform bone grafting.