illustrated by reference character 6 herein the left brace relative to the user need be discussed in detail in fig1 it can be seen that left brace 6 includes an upper side brace 8 and a lower side brace 9 with housing 10 holding a mechanical pivotal knee joint assembly to secure the knee brace to the leg 5 bands or straps 12 and 14 of flexible material such as fabric or leather are used with fasteners such as velcro u00ae or snaps one band 12 is wrapped around the upper leg to hold upper side brace 8 against that portion of the leg and if the lower side brace 9 is not held firmly against the lower leg portion by a shoe 13 or an actuating mechanism such as a heel plate or an ankle flexure a lower band 14 is used it is to be understood that the upper side brace 8 and lower side brace 9 should move relative to each other in a manner simulating as closely as possible ordinary leg movements it is this relative movement that is the essence of this invention in fig1 it can be seen that since the upper leg must move from a bent leg position to a straight leg position the upper side brace 8 must move relative to the lower side brace 9 as does a leg to this end knee joint housing 10 is made up of two elements.