Prosthesis for the at least partial replacement of a long bone and an adjacent joint, comprising an elongated rod (1) with a first end and a second end, as well as an articulated device (2) that is disposed at the second end of the rod (1), the rod (1) and the articulated device (2) being coupled through complementary conical plug couplings (18, 29), the rod having an inner rod (12) and a coaxial outer rod (11) , providing a length adjustment device (3) that activates the rod (1) along its axis (10) as a telescope and acts on the inner rod (12) and the outer rod (11), the device for adjusting the length (3) being made in a modular manner and provided with its proximal and distal end of complementary conical plug couplings (18, 19), the device for adjusting the length of a torsion lock is also provided ( 37) acting on drag, characterized in that at one of the two ends of the length adjustment device (3) a male conical plug coupling is provided and at the other end a female conical plug coupling, by which the torsion lock (37) is arranged on the outer rod (11) and fits into a longitudinal recess (15) on the inner rod (12), and by means of two diametrically opposed fixing screws, torsion of the inner rod is prevented ( 12) with respect to the articulated device (2).Prótesis para la sustitución al menos parcial de un hueso largo y de una articulación adyacente, que comprende un vástago alargado (1) con un primer extremo y con un segundo extremo, así como un dispositivo articulado (2) que se dispone en el segundo extremo del vástago (1), acoplándose el vástago (1) y el dispositivo articulado (2) a través de acoplamientos de enchufe cónicos complementarios (18, 29), presentando el vástago una varilla interior (12) y una varilla exterior coaxial (11), previéndose un dispositivo de ajuste de la longitud (3) que activa el vástago (1) a lo largo de su eje (10) a modo de telescopio y que actúa sobre la varilla interior (12) y la varilla exterior (11), realizándose el dispositi
