Shoulder 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.
• Multidirectional

• Previous shoulder dislocation
• Athletic activity, especially:
  • Baseball—pitching
  • Football—tackling
  • Tennis
  • Gymnastics
  • Weight-lifting
  • Any collision or contact sport
  • Volleyball
  • Swimming, especially backstroke or butterfly
• Congenital collagen disorders, such as:
  • Marfan syndrome—a connective tissue condition
  • Ehlers-Danlos syndrome—a condition in which patients have loose joints
• Hereditary Conditions

• Pain in the shoulder area
• Shoulder or arm weakness
• Shoulder may feel loose
• Shoulder may slip out of place
• Numb feeling down the arm

• X-rays
• MRI scan
• CT scan
• Arthroscopy

1. Non-surgical treatment will focus on reducing the strain at the shoulder in a downward or backward position during functional task performance. The therapist will likely present a number of restricted motions and ways to perform functional daily tasks without putting strain on the ligaments. In the case of a painful shoulder, the therapist will recommend anti-inflammatory techniques and positions of the shoulder at night and during sustained or repetitive task performance. The therapist will recommend strengthening exercises to the support muscles in order to improve safe reach and reduce the risk of recurrent dislocation.
2. Following a surgical procedure, the therapist will work closely with the surgeon to determine the safe motion patterns and range of motion. If the arm is kept still too long, the tightening procedure that was performed could limit the motion too much. If the shoulder is allowed to move too quickly, the ligaments could stretch back out and continue to cause the MDI.

• Doing regular exercises to strengthen the supporting muscles
• Using proper athletic training methods
• Increasing the duration or intensity of your exercises gradually
• Modifying activities to prevent excessive external rotation and overhead motions of the shoulder

• American Academy of Family Physicians

http://familydoctor.org

• American Academy of Orthopaedic Surgeons

http://orthoinfo.aaos.org

• Canadian Orthopaedic Association

http://www.coa-aco.org

• Canadian Orthopaedic Foundation

http://www.canorth.org

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