What are the other Names for this Condition? (Also known as/Synonyms)

• Atraumatic Onset Shoulder Instability
• Multidimensional Chronic Shoulder Instability
• Traumatic Chronic Shoulder Instability

What is Chronic Shoulder Instability? (Definition/Background Information)

• The shoulder joint is made up of 3 different bones - the shoulder blade (scapula), the collarbone (clavicle), and the upper arm bone (humerus)
• A shoulder dislocation is a painful and traumatic injury that occurs, when the top end of the humerus is forced out of the shoulder socket, either partially or completely. Once this injury occurs, the shoulder is susceptible to repeated episodes of dislocation. This is called Chronic Shoulder Instability due to traumatic onset, which usually occurs suddenly
• A high percentage of such injuries are caused by repetitive stress of the shoulder, due to athletic sports. Overall, young men have the highest occurrence rate of this condition
• Sometimes, Chronic Shoulder Instability can be due to a weak joint capsule, which occurs naturally without any trauma. This is called Atraumatic-Onset Shoulder Instability
• Atraumatic Onset Shoulder Instability may cause the joint to dislocate in many directions. Hence, it is called multidimensional instability (MDI) of shoulder joint
• The treatment of Chronic Shoulder Instability may include both nonsurgical and surgical methods. Without appropriate treatment, it is difficult to predict the prognosis of the condition

Who gets Chronic Shoulder Instability? (Age and Sex Distribution)

• Chronic Shoulder Instability may occur in individuals of all ages, races, ethnic groups, and gender
• Overall, the condition is likely to develop in young men, due to a greater frequency of their participation in high impact sports

What are the Risk Factors for Chronic Shoulder Instability? (Predisposing Factors)

Common risk factors associated with Chronic Shoulder Instability include:

• Individuals, who participate in sports that cause repetitive stress on the shoulder; physical activities, such as tennis or swimming
• Repetitive shoulder stress associated with certain occupations, such as construction
• Studies have indicated that Chronic Shoulder Instability has a genetic component and a family history of the condition may increase one’s risk

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Chronic Shoulder Instability? (Etiology)

Causes of Chronic Shoulder Instability include both Traumatic Chronic Shoulder Instability and Atraumatic Onset Shoulder Instability. These are:

• Direct trauma to the shoulder, associated with automobile accidents (Traumatic-Onset Chronic Shoulder Instability
• Chronic Shoulder Instability due to a weak shoulder capsule
• Participation in any rough or high-impact sports, such as football and rugby, can cause a sudden injury (Traumatic-Onset Chronic Shoulder Instability)
• Individuals, who incur repetitive stress to the shoulder joints, such as while participating in baseball (throwing), tennis, swimming, and gymnastics. These sports may cause a loosening-up of the capsule and ligaments, around the shoulder joint
• Occurring in only a small percentage of individuals, multidirectional instability involves the shoulder becoming unstable, due to weak capsule and ligaments surrounding the shoulder joint. This is called Atraumatic-Onset Shoulder Instability

What are the Signs and Symptoms of Chronic Shoulder Instability?

Signs and symptoms of Chronic Shoulder Instability include:

• Swelling, bruising, numbness of the shoulder
• Excruciating pain, difficulty moving the shoulder
• Visible deformity of the shoulder joint

How is Chronic Shoulder Instability Diagnosed?

Diagnostic methods that a physician may use to help diagnose Chronic Shoulder Instability include:

• Physical exam with medical history evaluation: The physician may examine the shoulder, and also check, if any arteries or nerves are trapped
• X-ray of shoulder joint: An x-ray of the shoulder joint is a common method in evaluating a shoulder dislocation. This diagnostic test will provide a clear image of the dislocation, show if any bones were broken, and help identify any other damage, to the shoulder joint
• Magnetic resonance imaging (MRI): An MRI is a more detailed scan that uses radio waves and a magnetic field to produce images that allow a physician, to view any damage to the bones and soft tissue that surrounds the shoulder joint

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Chronic Shoulder Instability?

Some complications of Chronic Shoulder Instability may include:

• Permanent damage to nerves and blood vessels
• Development of degenerative joint disease (osteoarthritis)

How is Chronic Shoulder Instability Treated?

Treatment measures of Chronic Shoulder Instability include both nonsurgical and surgical methods. The treatment also depends on the cause of the condition, whether it is traumatic-onset or atraumatic-onset.

Nonsurgical treatment measures include:

• Any activity that aggravates the shoulder condition should be avoided. The physician may advise the individual to refrain from participating in any physical activities, till the pain or symptoms get better
• Application of ice/cold pack to the shoulder, to reduce pain and swelling
• Non-steroidal anti-inflammatory oral medications, such as indomethacin and naproxen, may be used to treat Chronic Shoulder Instability. These medications can help decrease the pain and swelling
• Complete immobilization of the shoulder with a cast may be required to restrict movement in some cases
• Individuals are likely to need physical therapy exercises after the cast is removed. The goals of these exercises are to strengthen the shoulder muscles, improve flexibility, and decrease stiffness. A physical therapist will recommend an exercise program, to aid in treating the condition

Surgical treatment measures include:

• Shoulder arthroscopy: Arthroscopic surgery is a minimally-invasive surgical procedure that is used to visualize, diagnose, and repair, the shoulder joint using small instruments. These instruments are inserted through a small incision within the shoulder
• Capsular shift of shoulder joint: Capsular shift is a procedure that involves tightening the joint capsule, including the ligaments that stabilize the shoulder. This procedure is performed using an orthopedic device, called an arthroscope
• Labral repair (bankart repair) of shoulder joint: Labral repair is a surgical procedure to repair a tear to the labium, using fixation devices (suture anchors). Surgical sutures are then used to reattach the labium to the socket. This procedure is usually performed using an orthopedic device, called an arthroscope
• Anterior stabilization of the shoulder (latarjet protocol): This surgical procedure is performed in individuals, who experience repeated dislocations. During this procedure, a small piece of bone (coracoid) is removed from its attachment to the scapula. The coracoid and the muscle attachment are then placed into position, to front the shoulder socket. Once in position, the coracoid is screwed into the shoulder socket. The goal of this procedure is to provide stability to the shoulder joint
• Open surgery called open shoulder joint arthroplasty: Open surgery is an invasive procedure in which, an incision is made in the shoulder, to allow the physician to repair the damaged tissue, muscles, or tendons

How can Chronic Shoulder Instability be Prevented?

To prevent Chronic Shoulder Instability, individuals should be careful and consciously aware while performing any physical activities, such as sports, or even some normal daily activities that could lead to situations involving accidents. Children must be provided a safe environment to work, study, or play. Any possible dangers should also be anticipated and appropriate safety measures adopted.

A few ways to further help prevent unwanted injuries or Chronic Shoulder Instability include:

• Strengthening the muscles around the shoulder can reduce the risk of an unstable shoulder joint. This is especially true for multidimensional instability of joint
• Avoid any repetitive lifting or pulling (especially overhead) of objects that are heavy
• In sports, learn the correct techniques and avoid poor (overhead) throwing techniques that may cause unstable shoulder joints

What is the Prognosis of Chronic Shoulder Instability? (Outcomes/Resolutions)

• The long-term prognosis of Chronic Shoulder Instability is usually good, in a majority of the individuals. When properly treated, a high percentage of individuals regain their full strength and range of motion, in the affected shoulder
• However, some individuals with severe cases of shoulder instability may experience long-term adverse effects, due to damage to the surrounding structures

Additional and Relevant Useful Information for Chronic Shoulder Instability:

The following article links will help you understand some surgical treatment methods for Chronic Shoulder Instability:

http://www.dovemed.com/common-procedures/procedures-surgical/arthroscopy/

http://www.dovemed.com/common-procedures/procedures-surgical/arthroplasty-of-shoulder/