An apparatus for positioning an orthopedic implant, the apparatus includes a flexible substrate, at least first and second field-generating coils, and circuitry. The flexible substrate is formed into a three-dimensional (3D) shape and is coupled to a predefined location on the orthopedic implant. The at least first and second field-generating coils are formed in the flexible substrate, such that in the 3D shape the first and second field-generating coils have first and second respective axes that are not parallel to one another. The circuitry is mounted on the flexible substrate and electrically connected to the at least first and second field-generating coils, and is configured to drive the at least first and second field-generating coils with respective signals.
