title: Tension of knotted surgical sutures shows tissue specific rapid loss in a rodent model.
abstract: BACKGROUND
  Every surgical suture compresses the enclosed tissue with a tension that depends from the knotting force and the resistance of the tissue. The aim of this study was to identify the dynamic change of applied suture tension with regard to the tissue specific cutting reaction.
  
  
  METHODS
  In rabbits we placed single polypropylene sutures (3/0) in skin, muscle, liver, stomach and small intestine. Six measurements for each single organ were determined by tension sensors for 60 minutes. We collected tissue specimens to analyse the connective tissue stability by measuring the collagen/protein content.
  
  
  RESULTS
  We identified three phases in the process of suture loosening. The initial rapid loss of the first phase lasts only one minute. It can be regarded as cutting through damage of the tissue. The percentage of lost tension is closely related to the collagen content of the tissue (r = -0.424; p = 0.016). The second phase is characterized by a slower decrease of suture tension, reflecting a tissue specific plastic deformation. Phase 3 is characterized by a plateau representing the remaining structural stability of the tissue. The ratio of remaining tension to initial tension of phase 1 is closely related to the collagen content of the tissue (r = 0.392; p = 0.026).
  
  
  CONCLUSIONS
  Knotted non-elastic monofilament sutures rapidly loose tension. The initial phase of high tension may be narrowed by reduction of the surgeons' initial force of the sutures' elasticity to those of the tissue. Further studies have to confirm, whether reduced tissue compression and less local damage permits improved wound healing.
authors.affiliation: Department of Surgery, RWTH Aachen, Germany. cklink@ukaachen.de
authors.forename: Christian D
authors.initials: CD
authors.lastname: Klink
authors.forename: Marcel
authors.initials: M
authors.lastname: Binnebösel
authors.forename: Hamid P
authors.initials: HP
authors.lastname: Alizai
authors.forename: Andreas
authors.initials: A
authors.lastname: Lambertz
authors.forename: Klaus T
authors.initials: KT
authors.lastname: Vontrotha
authors.forename: Elmar
authors.initials: E
authors.lastname: Junker
authors.forename: Catherine
authors.initials: C
authors.lastname: Disselhorst-Klug
authors.forename: Ulf P
authors.initials: UP
authors.lastname: Neumann
authors.forename: Uwe
authors.initials: U
authors.lastname: Klinge
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003238:Connective Tissue / Q000503:physiopathology* / Q000601:surgery; D004195:Disease Models, Animal; D004867:Equipment Design; D005260:Female; D008422:Materials Testing; D011817:Rabbits; D015203:Reproducibility of Results; D013529:Surgical Wound Dehiscence / Q000503:physiopathology / Q000517:prevention & control*; D013536:Suture Techniques / Q000295:instrumentation*; D013537:Sutures; D013718:Tensile Strength; D014945:Wound Healing