Evaluation of tension obtained by use of three knots for tying cerclage wires by surgeons of various abilities and experience

ArticleinJournal of the American Veterinary Medical Association 220(3):334-6 · March 2002with5 Reads
Impact Factor: 1.56 · DOI: 10.2460/javma.2002.220.334 · Source: PubMed

    Abstract

    To compare tension of 3 cerclage wire knots tied by surgeons of various abilities and experience.
    Cross-sectional study.
    Participants and faculty at a postgraduate course in veterinary orthopedics.
    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.
    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.
    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.