Early bent knee prostheses: ancestors of K9.
D001154:Art / Q000266:history*; D001186:Artificial Limbs / Q000266:history; D049668:History, 15th Century; D049669:History, 16th Century; D006801:Humans; D007720:Knee Prosthesis / Q000266:history*; D007866:Leg; D008512:Medicine in the Arts; D010151:Paintings / Q000266:history*