An electric wire that has a conductor held by spacers in a covering of PTFE, continuous cells being formed between the covering, the spacers, and the conductor. One device comprises a sensor communicatively coupled to the wand to register points of interest on a first or second bone of the muscular-skeletal system and transmits location data related to the points of interest to the sensor to assess orthopedic alignment with the points of interest. One of the structures is electrically connected at its other end to the reading circuit by a cold electrical connection that is kept at a substantially constant potential.