An orthopaedic hip demonstration aid for demonstrating the fitting of an orthopaedic prosthesis to a human skeletal hip comprises a facsimile femur part including an elongate main portion incorporating an axial passage and consisting of two detachable parts secured together by magnetic attraction and received within the passage, and a detachable sheath portion consisting of two detachable parts secured together by magnetic attraction and received within the parts. The parts define a further axial passage adapted to detachably receive a shaft of the prosthesis such that a head of the prosthesis projects from an end of the femur part. Such an orthopaedic hip demonstration aid may be used to demonstrate surgical orthopaedic techniques in hip replacement.