DefinitionShoulder instability occurs when the upper-end of the arm bone, known as the humerus, slides partially or completely out of the shoulder socket.The disorder is classified by how much the humerus moves and the direction of the movement:
- Subluxation—The humeral head moves part way out of the shoulder socket.
- Dislocation—The humeral head moves completely out of the socket.
- Anterior—The humeral head moves toward the front.
- Posterior—The humeral head moves toward the back.
|Copyright © Nucleus Medical Media, Inc.|
CausesShoulder instability often results from injury.
Risk FactorsFactors that may increase your chance of shoulder instability include:
- Previous shoulder dislocation
- Athletic activity, especially:
- Any collision or contact sport
- Swimming, especially backstroke or butterfly
- Congenital collagen disorders, such as:
- Family members with shoulder instability
SymptomsSymptoms may come on suddenly or develop over time. Shoulder instability may cause:
- Pain in the shoulder area
- Shoulder or arm weakness
- Shoulder may feel loose
- Shoulder may slip out of place
- Numb feeling down the arm
More from Beliefnet
A systematic review found that participants given chewing gum after abdominal surgery may have a faster return to normal for their digestive system. Unfortunately, the quality of trials is low and more research will need to be done before this simple solution is confirmed.
Early Peanut Consumption Associated with Lower Risk of Peanut Allergy in High Risk Children
Breastfeeding May Decrease the Risk of Childhood Obesity
Tonsillectomy May Reduce Number of Sore Throat Days in Children