STIFLING?

["John B. Ayers" <ayers@plainfield.bypass.com>]

Can someone explain "STIFLING" to me.  I'm referring to
a momentary dislocation of the stifle joint.

At the last CTR,  I think it happened to  Meshack several times.
One rider said she knew of a horse who had done it
over 100 times in one Endurance Ride......that it is NOT
a problem unless he "locks up".

What would one do if it DID lock up?

Are there exercises for the horse that would minimize this?

John and Meshack (VT)