Some of the most versatile parts of the body are also some of the most susceptible to injuries, and the shoulder joint is a great example. You may not know this, but the shoulder is the most moveable joint in the entire human body—it has an even greater range of motion than the hips, neck or other flexible areas.
Unfortunately, this remarkable flexibility and range of motion can result in shoulder instability, or chronic shoulder instability.
What is Chronic Shoulder Instability?
Within the shoulder, your upper arm bone connects to your torso by the shoulder socket, called the glenoid. Shoulder instability refers to any time the upper arm bone is forced out of the glenoid, usually by a trauma or long term wear and tear.
A single instance of shoulder instability makes you more likely to have repeated instances in the future, and when this happens frequently, it is known as chronic shoulder instability. These dislocations of the shoulder can be partial (called a subluxation) or complete.
Shoulder instability is generally caused by one of three different underlying issues:
- 1. Previous dislocation: Any previous issues with shoulder instability lead to a higher chance of a recurrence. A shoulder that’s been dislocated will often feel unstable afterward, and it’s possible for cartilage near the glenoid to tear. This cartilage often won’t ever fully heal or will heal too loosely, and leave you open to future problems. For people under 35, repetitive shoulder instability will be present in about 80 percent of original cases.
- 2. Repetitive strain: For people whose shoulder instability isn’t caused by a previous dislocation, the most common cause is loose ligaments in the shoulders. Sometimes people are just born this way, and in other cases this happens because of long term wear and tear on the shoulder joint. Many sports or jobs require the same repeated arm motions over and over again, and this can weaken the joints.
- 3. Multidirectional instability: This is a less common cause where the shoulder is unstable despite no history of dislocations or repetitive strain. The shoulder might dislocate in multiple directions, and is often a sign that people are “double jointed” and have loose ligaments in other parts of the body besides just the shoulder.
There are a few common symptoms of chronic shoulder instability:
- • Shoulder pain
- • Repeated shoulder dislocations or feelings of the shoulder “giving out”
- • Constant feeling as if the shoulder is loose or slipping out of the joint
Diagnosis and Treatment
To diagnose chronic shoulder instability, your doctor will perform a few specific examinations:
- • Physical exam: Your doctor will ask you about the symptoms you’re having, and discuss any medical history relating to the shoulder or joints. They may ask you to test the ligaments for looseness with certain movement exams.
- • X-ray: Imaging can help show any injuries to bones that form the shoulder joint.
- • MRI (magnetic resonance imaging): This is a more detailed imaging technology that can help the doctor find injuries to the ligaments and tendons around the joint, rather than the bones.
When it’s possible, shoulder instability will be treated without invasive surgery. Some of the non-surgical options that you might be introduced to include:
- • Physical therapy: To help strengthen muscles and increase the stability of the entire shoulder joint.
- • Activity changes: Your doctor may recommend changing a few exercise or other habits to stay away from activities that aggravate your symptoms.
- • Medication: Painkillers like aspirin and ibuprofen—drugs that do not contain any steroids—can help with pain and inflammatory symptoms.
In some cases, though, surgery is necessary to correct long term chronic shoulder instability. There are two primary types of surgery performed for shoulder instability:
- • Arthroscopic surgery: This is a less invasive procedure in which your surgeon will use small incisions and a miniature camera to look inside the shoulder, and repair the joint using small instruments. You can leave the hospital on the same day you get this procedure.
- • Open surgery: This is when a larger incision is made and the surgeon repairs the joint while viewing it directly with their eyes, rather than through cameras. Open surgery is more invasive, but it can also be more effective and prevent future issues in many cases.
If you’re concerned you might have the symptoms of chronic shoulder instability, speak to your doctor about the most minimally invasive ways to get treated and eliminate symptoms.
Michael Carlson, MD
Orthopedics is rewarding for me because it allows me to help patients with injuries and get them back into action quickly. I love meeting people of all ages in my practice—I see kids, athletes, adults and retirees. I enjoy being able to understand people’s unique situations and trying to help them recover. I tend to be conservative with my surgical treatment, and much of my training is in minimally-invasive procedures, such as arthroscopy.
“Chronic Shoulder Instability.” American Academy of Orthopedic Surgeons. http://orthoinfo.aaos.org/topic.cfm?topic=a00529
“Shoulder Instability.” SportsMD. http://www.sportsmd.com/shoulder-injuries/shoulder-instability/