Biomechanical analysis of chlorhexidine power irrigation to disinfect contaminated anterior cruciate ligament grafts

Am J Sports Med. 2011 Jul;39(7):1528-33. doi: 10.1177/0363546511401175. Epub 2011 Apr 8.

Abstract

Background: Accidental graft contamination is a likely complication to occur in an orthopaedic sports medicine surgeon's career. There are no clinical outcome studies to direct management, and a recent survey showed that preferred management varied. Three liters of 2% chlorhexidine power irrigation has been shown to be an efficient and effective disinfection protocol; however, the biomechanical sequelae of this disinfection protocol to the graft are unknown.

Purpose: The purpose of this study was to determine if 3 L of 2% chlorhexidine power irrigation used to disinfect contaminated anterior cruciate ligament (ACL) grafts significantly weakens the graft at time zero.

Study design: Controlled laboratory study.

Methods: Eight fresh bovine superficial digital flexor tendons underwent disinfection protocol with 3 L of 2% chlorhexidine power irrigation. Contralateral tendons served as the control. Tendons were preconditioned and loaded to failure.

Results: The average ultimate failure load for the control tendons and disinfected tendons was 4081 ± 654.4 N and 4146 ± 723.2 N, respectively. The average ultimate failure stress for the control tendons and disinfected tendons was 97.10 ± 12.03 MPa and 95.18 ± 11.79 MPa, respectively. The average stiffness for the control tendons and disinfected tendons was 546.20 ± 28.16 N/mm and 539.2 ± 25.93 N/mm, respectively. The P values for ultimate failure load, ultimate failure stress, and stiffness showed no statistically significant difference between the chlorhexidine and control tendons.

Conclusion: Disinfecting tendons with 3 L of 2% chlorhexidine power irrigation does not adversely weaken the tendon's tensile mechanical properties.

Clinical relevance: Three liters of 2% chlorhexidine power irrigation can effectively disinfect a contaminated ACL graft without weakening the graft.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anterior Cruciate Ligament
  • Biomechanical Phenomena
  • Cattle
  • Chlorhexidine / pharmacology*
  • Disinfectants / pharmacology*
  • Disinfection / methods
  • Elasticity / drug effects
  • Tendons / drug effects*
  • Tendons / physiology*
  • Tensile Strength / drug effects

Substances

  • Disinfectants
  • Chlorhexidine