Shoulder Instability

The shoulder is an inherently unstable joint and depends on the surrounding muscles, capsule and ligaments for support and stability. These structures may be congenitally loose or damaged as a result of injury.

This can lead to excessive movement of the end of the arm bone in the socket, or if due to a high-energy injury, dislocation of the joint. The latter injury may be associated with damage to the nerves and blood vessels of the upper limb, and require urgent medical attention.

Causes and Risk Factors:
Significant trauma to a previously healthy shoulder joint, resulting in partial or complete dislocation
Repetitive overhead motions, leading to wear and tear on the joint and stretching of the shoulder capsule
Congenital factors like hyperlaxity syndrome, which cause general looseness in the joint and surrounding ligaments, tendons, and muscles

Signs and Symptoms:
Swelling
Numbness
Weakness
Bruising
Shoulder joint instability
Sensation of the shoulder popping out

Diagnosis:
Comprehensive history and physical examination
Imaging studies such as X-rays, ultrasound, MRI, and CT scans

Treatment may include:
Rest
Ice application and pain relief with nonsteroidal anti-inflammatory drugs (NSAIDs)
Physiotherapy