There is provided a brace for stabilizing a uniting pivoting joint disposed between first and second limb structures of a living being. The brace comprises upper and lower frame members, each encompassing the first and second limb structures respectively, and a pivoting joint member comprised of two opposing pivoting assemblies. The assemblies include a limb extension slot having an adjustable length. The slot is located on at least one of the upper or lower frame members. The assemblies also include an exteriorly accessible limb extension regulator for regulating the limb extension slot length. The limb extension regulator is coupled to the limb extension slot. The pivoting assembly further includes an arm member comprised of upper and lower ends, each being pivotally connected to the upper and lower frame members, respectively. The arm member further includes a regulation portion retained in the limb extension slot.