title: Evaluation of tension obtained by use of three knots for tying cerclage wires by surgeons of various abilities and experience.
abstract: OBJECTIVE
  To compare tension of 3 cerclage wire knots tied by surgeons of various abilities and experience.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Participants and faculty at a postgraduate course in veterinary orthopedics.
  
  
  METHODS
  Subjects tied a cerclage of their choice on an instrumented tying stand that displayed the tension on a computer. Mean tensions in cerclage wires tied with twist, single loop, or double loop knots were compared. The relationship between level of surgeon experience and tension achieved was examined.
  
  
  RESULTS
  29 twist, 30 single loop, and 16 double loop wires were analyzed. Mean +/- SD tension for twist knots was significantly less than for single loop knots (82.3+/-46.1 vs 166.6+/-42.2 N, respectively). Double loop knots achieved significantly greater tension (392.0+/-116.6 N) than twist and single loop knots did, even though few participants had ever tied this knot previously. There was no correlation with experience of the participant. For twist knots, wiggling the wire during cutting and pushing the twist over to flatten it to the bone further reduced tension.
  
  
  CONCLUSIONS
  Cerclage applied with a twist knot does not compress fracture fragments as effectively as cerclage applied with single loop or double loop techniques. Because greater compression of fragments will improve the stability of a fracture, a surgeon should strive to maximize the tension in the cerclage that they use. Experience and abilities of the surgeon are not associated with ability to tie cerclage wires tightly.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
authors.forename: Simon C
authors.initials: SC
authors.lastname: Roe
mesh_terms: D000818:Animals; D001864:Bone Wires / Q000662:veterinary; D001842:Bone and Bones / Q000601:surgery*; D003430:Cross-Sectional Studies; D004520:Education, Veterinary; D050723:Fractures, Bone / Q000601:surgery / Q000662:veterinary*; D006801:Humans; D009985:Orthopedics / Q000662:veterinary; D013522:Surgery, Veterinary / Q000592:standards; D013536:Suture Techniques / Q000662:veterinary*