title: Polydimethylsiloxane pressure sensors for force analysis in tension band wiring of the olecranon.
abstract: BACKGROUND
  Several different surgical techniques are used in the treatment of olecranon fractures. Tension band wiring is one of the most preferred options by surgeons worldwide. The concept of this technique is to transform a tensile force into a compression force that adjoins two surfaces of a fractured bone. Currently, little is known about the resulting compression force within a fracture.
  
  
  OBJECTIVE
  Sensor devices are needed that directly transduce the compression force into a measurement quality. This allows the comparison of different surgical techniques. Ideally the sensor devices ought to be placed in the gap between the fractured segments.
  
  
  METHODS
  The design, development and characterization of miniaturized pressure sensors fabricated entirely from polydimethylsiloxane (PDMS) for a placement within a fracture is presented. The pressure sensors presented in this work are tested, calibrated and used in an experimental in vitro study.
  
  
  RESULTS
  The pressure sensors are highly sensitive with an accuracy of approximately 3 kPa. A flexible fabrication process for various possible applications is described. The first in vitro study shows that using a single-twist or double-twist technique in tension band wiring of the olecranon has no significant effect on the resulting compression forces.
  
  
  CONCLUSIONS
  The in vitro study shows the feasibility of the proposed measurement technique and the results of a first exemplary study.
authors.affiliation: Department of Microsystems Engineering (IMTEK), Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.|Department of Orthopedic Surgery and Traumatology, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Zens
authors.affiliation: Department of Microsystems Engineering (IMTEK), Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Goldschmidtboeing
authors.affiliation: Department of Orthopedic Surgery and Traumatology, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Wagner
authors.affiliation: Department of Orthopedic Surgery and Traumatology, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Kilian
authors.initials: K
authors.lastname: Reising
authors.affiliation: Department of Orthopedic Surgery and Traumatology, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Norbert P
authors.initials: NP
authors.lastname: Südkamp
authors.affiliation: Department of Microsystems Engineering (IMTEK), Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Woias
mesh_terms: D000377:Agnosia; D001696:Biomechanical Phenomena; D004129:Dimethylpolysiloxanes / Q000627:therapeutic use*; D004551:Elbow Joint / Q000601:surgery*; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods*; D005593:Fracture Fixation, Internal / Q000379:methods*; D006801:Humans; D056740:Olecranon Process / Q000601:surgery*; D013314:Stress, Mechanical
chemical_list: D004129:Dimethylpolysiloxanes
keywords: Polydimethylsiloxane (PDMS); compression force; pressure sensor; tension band wiring