Abstract: A joint having two-axis construction having a distal member and a main member joined in co-linear pivotal relation that provides enhanced joint strength and compactness. Hydraulics further provide variable extension assist and an infinite number of flexion stops for controlled flexion flow, and two gears provide a functional gear ratio that also promotes compact construction by reducing the amount of hydraulic piston travel required for maximum joint extension. A drive gear associated with the main member is positioned between the distal end of the piston and a transfer gear partially press-fit into a cut-out in the distal member, to provide needed radial hydraulic force transfer. Although it is contemplated for joint use to be primarily in orthotic devices that assist the movement of an inadequately functioning body limb, any application for which the mechanical joint's compact configuration would provide assistance or technical advantage is considered to be within its scope.