A rotary joint comprises outer member with flanges at either end, having inner rotary shaft and annular depression around the rotary shaft, one-way clutch for externally engaging the rotary shaft, metal bush for externally engaging the one-way clutch, synthetic resin bush for externally engaging the metal bush, brake bush for externally engaging the synthetic resin bush, cylindrical projection which is fitted in annular depression of the outer member located outside the brake bush, inner member with flanges at either end, and a stopper mechanism for controlling the range of rotary shaft rotation which is installed at inner projection of rotary shaft. Such a construction enables the execution of torque tests with a single unit of an articulation prosthetic implement rotary joint.