An apparatus for transcutaneously transferring an amount of energy to an implantable orthopaedic device includes a primary coil. The primary coil has a resonant frequency matched to a resonant frequency of a secondary coil, which may form part of the implantable orthopaedic device. The primary coil may have an aperture configured to receive a portion of a patient's body or may include a substantially “C”-shaped core. A power circuit may be coupled with the primary coil to provide power to the coil. The apparatus may also include a wireless receiver, a measuring device, and/or a display.