Laxity
A joint instability (or bladder joint) is a reduction in the secure, stable guidance of the joint-forming bones during a movement accompanied by an abnormal increase in the range of motion
This guidance is normally active through the musculature and passively through the capsule and tape apparatus.
Causes of a fault are:
 If there is a considerable increase in the range of motion possible, this is referred to as a subluxation. If the joint is completely released, there is a dislocation (dislocation).  Single-level Edit source text Edit source text 
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