An apparatus to aid removal of a prosthetic implant (2, 62) cemented into bonecomprises an adapter (5, 35, 45, 55) to engage a proximal end (9, 63) of the implant(2, 62), a clamp screw (1, 6, 56) to hold said engaged end (9, 63) to the adapter (5,35, 45, 55) in good acoustic contact, a generator (23) for torsional or longitudinalmode ultrasonic vibrations and a coupling link (1, 61) to transmit the ultrasonicvibrations to the adapter means (5, 35, 45, 55) and thence to the implant (2, 62).The proximal end (9,63) of the implant (2, 62) is ideally gripped between a conicaltip (57) of the clamp screw (56) and a raised portion (41, 54) of the adapter (35,45, 55) to avoid damping flexural mode oscillations induced in the implant.
