Shoulder instability is common in people with loose joints, those who are very flexible or can happen from a traumatic injury. Instability, is a term we use when the shoulder joint is prone to a dislocation – where the upper arm bone partially or completely slips out of the shoulder socket. The specific cause of shoulder instability can vary and often has one or more of the following causes.
What Causes Shoulder Instability?
- A traumatic shoulder injury: One of the most common causes of shoulder instability is a traumatic event, such as a fall, car accident, or sports-related injury, that leads to a dislocation or laxity in supporting structures of the shoulder – the ligaments and labrum. This makes the shoulder more prone to dislocation in the future.
- Recurrent Dislocations: If an individual has experienced a previous shoulder dislocation, they are at increased risk of future instability. Each dislocation episode can cause further damage to the stabilizing structures of the shoulder, making it more likely to happen again.
- Ligament Laxity: Some individuals naturally have looser ligaments and joint capsules in their shoulder joints. This genetic condition can predispose them to shoulder instability, even without a specific injury.
- Muscle Weakness: Weakness in the muscles, surrounding the shoulder joint, particularly the rotator cuff muscles can also contribute to shoulder instability making it less able to hold the humerus (upper arm bone) securely in the socket.
- Congenital Factors: Some individuals may be born with structural abnormalities in their shoulder joint that make them more susceptible to instability. These congenital factors can include shallow or poorly developed shoulder sockets (glenoid), which provide less stability to the joint.
- Overuse or Repetitive Movements: Athletes or individuals engaged in activities that involve frequent overhead motions, such as baseball pitchers or swimmers, can develop shoulder instability due to the repetitive stress on the joint. Over time, this can lead to wear and tear and a breakdown of the stabilizing ligaments.
- Degenerative Changes: This natural aging process can lead to weakening of the ligaments and labrum, making the shoulder more susceptible to instability.
- Previous Surgeries: Prior shoulder surgeries, especially those involving the repair of rotator cuff tears or labral tears, can alter the shoulder’s anatomy and stability. In some cases, surgical procedures may contribute to shoulder instability or make it worse.
- Inflammatory Conditions: Certain medical conditions, such as rheumatoid arthritis or other autoimmune disorders, can affect the shoulder joint and its supporting structures.
Treating Shoulder Instability
Our team of sports medicine specialists is specially trained to diagnose and treat shoulder instability. It is important to have a thorough exam and diagnostic testing to determine the cause of shoulder instability. The goal of treatment is always to reduce pain, improve shoulder stability, and prevent further dislocations. This allows the individual to return to their regular activities, without a concern of doing further damage to the shoulder. If left untreated, chronic instability can lead to a more serious injury or arthritic changes in the shoulder.
Our team starts with a conservative treatment approach, which often includes physical therapy to strengthen the shoulder muscles and improve stability. We may also recommend anti-inflammatory medications that can reduce swelling and pain along with activity modification to limit the use of a shoulder. Using a brace or a sling can immobilize the shoulder temporarily while it heals. In cases where that is not effective or cases of severe or recurrent instability, surgery may be necessary. If that is the case, much can be done to restore the function of the shoulder. We are able to use minimally invasive surgical techniques to repair torn ligaments, tighten the joint capsule, or repair other structural issues to stabilize the shoulder. In some cases, open shoulder surgery is required to reconstruct the shoulder and restore stability. Surgery to stabilize the shoulder has a high success rate and allows individuals to get back to the life and activities they love without the pain or worry of a shoulder dislocation.