title: 3D visualized robot assisted reduction of femoral shaft fractures: evaluation in exposed cadaveric bones.
abstract: The main problems in intra-medullary nailing of femoral shaft-fractures are leg-length discrepancies and rotational differences with an incidence of 2-18% and 20-40% respectively. These may lead to severe postoperative sequelae such as additional correctional operations and difficult rehabilitation. Insufficient visualization can be considered the main reason for these complications. Finally, retention of the fragments in the correct alignment before nail insertion is difficult. To overcome these problems we established a robotic telemanipulator system to support the reduction process. It was evaluated in 30 fractures of embalmed human femora. Specially programmed software used an image-dataset which was acquired by an isocentric 3D fluoroscope. For visualization, a surface projection was generated. Localization and tracking of the fragments and the robot-arm as well as accuracy measurement was performed by using an optical navigation system. Manipulation was controlled via a force-feedback joystick. This way, collisions of the fragments were transmitted back to the surgeon. At the end of the reduction the robot could rigidly retain the fragments' position.
authors.affiliation: Department of Trauma Surgery, Hannover Medical School, Hannover, Germany. m.oszwald@web.de
authors.forename: Markus
authors.initials: M
authors.lastname: Oszwald
authors.forename: Ralf
authors.initials: R
authors.lastname: Westphal
authors.forename: Jan
authors.initials: J
authors.lastname: Bredow
authors.forename: Ralph
authors.initials: R
authors.lastname: Gaulke
authors.forename: P F
authors.initials: PF
authors.lastname: O'Loughlin
authors.forename: Tobias
authors.initials: T
authors.lastname: Huefner
authors.forename: Friedrich
authors.initials: F
authors.lastname: Wahl
authors.forename: Christian
authors.initials: C
authors.lastname: Krettek
authors.forename: Thomas
authors.initials: T
authors.lastname: Goesling
mesh_terms: D000465:Algorithms; D000704:Analysis of Variance; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000517:prevention & control; D001858:Bone Nails; D002102:Cadaver; D004867:Equipment Design; D005264:Femoral Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D005471:Fluoroscopy / Q000295:instrumentation; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007870:Leg Length Inequality / Q000000981:diagnostic imaging / Q000517:prevention & control; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000517:prevention & control; D012371:Robotics; D012984:Software; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D019415:Torque