An 'open chain' exercise in one in which the end of the limb being exercised is free from contact with any surface for some part of the excursion.
Full arc extension - open kinetic chain.
Beginning of straight leg raise - open kinetic chain.
Hip abduction - open kinetic chain.
Open kinetic chain
The concept of the kinetic chain is that each part of the limb being exercised is connected in a functional chain. A kinetic chain is the notion that these joints and segments have an effect on one another during movement. When one part of the chain moves, it affects the next member of the chain. During exercise, the physiotherapist may recommend that the exercise regime should focus upon the chain being open or closed.
Open versus closed chain kinetic exercises after anterior cruciate ligament reconstruction. A prospective randomized study.. Bynum EB, Barrack RL and Alexander AH. Am J Sports Med. 1995 Jul-Aug;23(4):401-6.
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