Shoulder Capsular Shift
The shoulder can become unstable and the ball on the upper end of the arm (humerus) either partially shift out of joint (subluxate) or completely dislocate out of the socket (glenoid). The shoulder looseness can either be caused by a tear of the capsule (sack surrounding the shoulder) and ligaments (glenoid) or by simply stretching of the capsule and ligaments. Laxity of the capsule may also be hereditary in some patients or acquired due to repetitive insult and stretching in others. When the shoulder is stressed, particularly in an overhead and outwardly rotated motion, painful instability and occasionally a brief period of weakness may result. The shoulder may have generalized laxity (instability) in more than one direction, which is termed ‘multidirectional laxity’. Ice, non-steroidal anti-inflammatory medication, and physical therapy to strengthen the muscles that surround the shoulder are often helpful in minimizing symptoms of shoulder instability due to tissue laxity. Activity modification may be necessary in an attempt to avoid recurrent symptoms. When those measures are ineffective and your pain and disability are unacceptable, surgery is indicated. When the capsule and ligaments are excessively lax, but not torn, tightening them is usually effective. Tiny arthroscopic incisions are created to facilitate the delivery of small instruments. The capsule is lightly excoriated (similar to preparing a tire patch) to stimulate a healing response. Small hooks are used to deliver sutures, which are used to plicate the capsule and decrease the volume and elasticity of the ligaments. The process is similar to placing ‘darts’ in clothing material. Multiple sutures are usually necessary and may need to be placed both in the front and back of the shoulder. Following surgery, the shoulder is immobilized in a sling for approximately 4 – 6 weeks. Physical therapy with range of motion exercises generally begins at 2 – 3 weeks, with light strengthening at 6 – 8 weeks. Unrestricted activity is permitted after six months.