Abstract: An endoprosthesis of the innominate bone body comprises a visor curved longitudinally and transversely so as to form a concave surface which faces the head of the femur, and elements for fixing the visor. One of the elements for fixing the visor is essentially a wedge curved longitudinally and transversely so as to form a convex surface, a concave surface and a crescent-shaped base. The wedge base is made integral with the visor in such a manner that the concave surfaces of the visor and wedge pass into each other. A plurality of through holes are provided in the wedge so that osseous tissue can accrete thereinto. The holes open into the convex and concave surfaces of the wedge, and a number of slots are formed on the wedge taper edge throughout the wedge length so as to establish teeth. Serving as the other fixing elements are screws adapted to fit in the holes opening into the base of the wedge and into the convex surface thereof.