System and method for identifying a landmark

#1. Technical Field

#This disclosure relates to identification of blind landmarks on orthopaedic implants.

#2. Description of the Related Art

#FIG. 1 illustrates a system for identifying a landmark.

#FIG. 2 is a sectional view of an orthopaedic implant of FIG. 1.

#FIG. 3 is a partial sectional of the implant of FIGS. 1 and 2 illustrating the sensor mounting.

#It should be understood that the drawings are not necessarily to scale and that the disclosed implementations are sometimes illustrated diagrammatically and in partial views. In certain instances, details which are not necessary for an understanding of the disclosure or which render other details difficult to perceive may have been omitted. It should be understood, of course, that this disclosure is not limited to the particular implementations illustrated herein.

#Referring to the accompanying drawings in which like reference numbers indicate like elements, FIG. 1 illustrates one disclosed system 10 for identifying a landmark. The system 10 may include a processor 12, a magnetic field generator 16, a landmark identifier 18, and an orthopaedic implant assembly 28. The system 10 may also include a monitor 14 electrically connected to the processor 12 and an insertion handle 40 removably attached to the orthopaedic implant assembly 28. The processor 12 is depicted as a desktop computer in FIG. 1 but other types of computing devices may be used. As examples, the processor 12 may be a desktop computer, a laptop computer, a personal data assistant (PDA), a mobile handheld device, or a dedicated device. The magnetic field generator 16 is a device available from Ascension Technology Corporation of 107 Catamount Drive, Milton Vt., U.S.A.; Northern Digital Inc. of 103 Randall Drive, Waterloo, Ontario, Canada; or Polhemus of 40 Hercules Drive, Colchester Vt., U.S.A. Of course, other generators may be used. As examples, the field generator 16 may provide a pulsed direct current electromagnetic field or an alternating current electromagnetic field. The system 10 may also include a control unit (not shown) connected to the magnetic field generator 16. The control unit controls the field generator 16, receives signals from small mobile inductive sensors, and communicates with the processor 12, either by wire or wirelessly. The control unit may be incorporated into the processor 12 either through hardware or software.

#The system 10 is a magnetic position tracking system. For illustrative purposes, the system 10 may include a magnetic field generator 16 comprised of suitably arranged electromagnetic inductive coils that serve as the spatial magnetic reference frame (i.e., X, Y, Z). The system 10 may also include small mobile inductive sensors, which are attached to the object being tracked. It should be understood that other variants could be easily accommodated. The position and angular orientation of the small mobile inductive sensors are determined from its magnetic coupling to the source field produced by magnetic field generator 16.