Abstract: The present invention comprises a metal electrode (2) electrically insulated on the active surface thereof and which is connected to a high frequency circuit (4) and transmits current capacitatively. This apparatus is characterized in that an axial reciprocating movement of adjustable rate is applied to the electrode (2) and the intensity of the percussion on the patient's affected area is also adjustable. The electrode is removeably attached to a stem (7) resiliently engaging (21) the periphery of a cam (11) driven by a geared motor (13, 14) housed in a grip (16) of the mechanical device (1). This comprises a nozzle (17) through which the electrode (2) projects and which is provided with a replaceable front portion (18) for coupling portions of different length. The mechanical device (1) is connected to a box (3) containing the electronic circuit and the percussion rate control device for the electrode holder stem (7).