title: Pull-out strength of 0°/30° Kirschner wire syringe external fixators with and without polymer augmentation: a biomechanical study.
abstract: BACKGROUND
  Hand external fixators are in use worldwide and insulin syringes can generally be found in an operating room.
  
  
  OBJECTIVE
  To compare the pull-out strength between degrees of Kirschner wire fixation (0° and 30°) and the effect of filling an insulin syringe with polymer
  
  
  METHODS
  Pull-out strength was compared between a syringe externalfixator and a bone or plastic tube model. Fifty-two plastic tube models and 20 dry phalangeal bones were included The syringe external fixator was attached via two Kirschner wires. Four variations were studied: 0° non-polymer 0° with polymer augmentation, 30° non-polymer and 30° with polymer augmentation. The pull-out strength was measured in each group.
  
  
  RESULTS
  The strength of polymer augmentation was higher than non-polymer augmentation at 0° (p = 0.0003) and 30° (p = 0.0002). The Kirschner wire at 30° provided more pull-out strength than at 0° (p = 0.0003) using the syringe with no polymer However, using the syringe with polymer augmentation, there was no significant difference (p = 0.5136).
  
  
  CONCLUSIONS
  Polymer augmentation significantly increases the pull-out strength at both degrees offixation. The degree of fixation significantly increases the pull-out strength only in the non-polymer group, where pinning at 30° was superior to 0°.
authors.forename: Pichitchai
authors.initials: P
authors.lastname: Atthakomol
authors.forename: Noppadol
authors.initials: N
authors.lastname: Wangjiraphan
authors.forename: Supachard
authors.initials: S
authors.lastname: Krudtong
authors.forename: Jirasak
authors.initials: J
authors.lastname: Panya
authors.forename: Sirichai
authors.initials: S
authors.lastname: Leuvitoonvejchakij
authors.forename: Jirachart
authors.initials: J
authors.lastname: Kraisarin
authors.forename: Kanit
authors.initials: K
authors.lastname: Sananpanich
mesh_terms: D001696:Biomechanical Phenomena; D001864:Bone Wires; D016267:External Fixators; D005592:Fracture Fixation / Q000379:methods*; D006230:Hand Injuries / Q000601:surgery; D006801:Humans; D008422:Materials Testing; D008954:Models, Biological; D011108:Polymers; D013594:Syringes; D013718:Tensile Strength
chemical_list: D011108:Polymers