title: [A new parallel drill guide for navigating femoral neck screw placement. Development and evaluation].
abstract: BACKGROUND
  Trauma navigation applications employ conventional mechanical surgical instruments for the simulation of drilling trajectories. Few complex mechanical targeting instruments, such as guides with fixed angles or with multiple parallel cannulas, have been adapted into trauma navigation systems. We have integrated a complex mechanical tool, the parallel drill guide (PDG) for the minimally invasive treatment of femoral neck fractures, into a trauma navigation module. The combined advantage of a complex yet commonly used mechanical tool with the benefits of fluoroscopic navigation was evaluated.
  
  
  METHODS
  To adapt the conventional PDG to a fluoroscopic navigation system, the instrument was fitted with a non-detachable reflective marker array. Navigation engineers developed custom software to enable visualization of the navigated PDG. A comparison of conventional versus navigated PDG techniques was performed on plastic bone models and cadavers. No software or mechanical failures occurred with the navigated PDG procedures.
  
  
  RESULTS
  While the total operative time was 30% more with navigation compared with conventional techniques, the total radiation time for the navigated group was reduced by more than 60%. This study demonstrates the successful integration of a cannulated parallel drill guide with a fluoroscopic navigation system.
  
  
  CONCLUSIONS
  The continuous display of the complex PDG mechanical instrument, with multiple parallel virtual trajectories, enables safe and accurate parallel screw placement. The integration of complex mechanical instrumentation with navigation for the accurate placement of hardware represents an attractive direction in multiple trauma applications.
authors.affiliation: Unfallchirurgische Klinik, Medizinische Hochschule, Carl Neuberg Strasse 1, 30625 Hannover, Deutschland. kendoff.daniel@mh-hannover.de
authors.forename: D
authors.initials: D
authors.lastname: Kendoff
authors.forename: T
authors.initials: T
authors.lastname: Hüfner
authors.forename: M
authors.initials: M
authors.lastname: Citak
authors.forename: C
authors.initials: C
authors.lastname: Maier
authors.forename: F
authors.initials: F
authors.lastname: Wesemeier
authors.forename: A
authors.initials: A
authors.lastname: Pearle
authors.forename: C
authors.initials: C
authors.lastname: Krettek
mesh_terms: D001863:Bone Screws; D002102:Cadaver; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005264:Femoral Fractures / Q000601:surgery*; D005269:Femur / Q000601:surgery*; D005593:Fracture Fixation, Internal / Q000295:instrumentation*; D006801:Humans; D010027:Osteotomy / Q000295:instrumentation* / Q000379:methods; D019919:Prosthesis Implantation / Q000295:instrumentation* / Q000379:methods*