Abstract: The present invention relates to devices for moving a two bodies 1, 2 relative to each other. The device of the invention is essentially characterized by the fact that it comprises two parts 11, 12, a projecting portion 14 mounted to co-operate with one of the two parts, a cavity 13 formed in the other part and complementary in shape to the projecting portion 14, the two parts 11, 12 being mounted to move relative to each other in such a manner that the projecting portion 14 penetrates into the cavity 13, the projecting portion 14 forming a closed loop made of an electrically conductive material which completely surrounds a magnetic core 101 which is not completely surrounded by the mechanism 100 for interconnecting the projecting portion 14 and the first part 11. The invention is applicable in particular to a bone prosthesis, a medullary nail for lengthening bones, a rod for correcting and supporting the spinal column.

Abstract: The present invention relates to devices for moving a two bodies 1, 2 relative to each other. The device of the invention is essentially characterized by the fact that it comprises two parts 11, 12, a projecting portion 14 mounted to co-operate with one of the two parts, a cavity 13 formed in the other part and complementary in shape to the projecting portion 14, the two parts 11, 12 being mounted to move relative to each other in such a manner that the projecting portion 14 penetrates into the cavity 13, the projecting portion 14 forming a closed loop made of an electrically conductive material which completely surrounds a magnetic core 101 which is not completely surrounded by the means 100 for interconnecting the projecting portion 14 and the first part 11. The invention is applicable in particular to a bone prosthesis, a medullary nail for lengthening bones, a rod for correcting and supporting the spinal column.