title: Biomechanical comparison between the modified rolling-hitch and the modified finger-trap suture techniques.
abstract: OBJECTIVE
  The purpose of this study was to characterize the biomechanical effect of two grasping suture techniques used during ligament reconstruction: the modified rolling-hitch (MRH) and the modified finger-trap (MFT).
  
  
  METHODS
  Flexor profundus tendons were harvested from fresh pig hind-leg trotters. Each specimen was mounted on an electro-mechanic universal testing machine (Instron 3367). In half of all tendons (15 specimens), the suture was passed around the tendon following the MRH knot (Group 1). In the remaining half of all tendons (15 specimens), the suture was passed over a distance of 30 mm according to the MFT suture technique (Group 2). As per standard intra-operative technique, a 1 cm residual tendon stub was left free from suture in all samples. All specimens were preconditioned to a load of 50 N for 10 min, followed by three cycles loading between 50 and 120 N. At this point, each sample was cyclically tensioned between 35 and 240 N, at 1 Hz for 200 cycles. Load-to-failure test was then carried out at a rate of 200 mm/min.
  
  
  RESULTS
  Rupture of the suture material at the knot was the mode of failure in all specimens during the loaded to failure test. Significant difference was found between Group 1 vs Group 2 for the elongation between the 0th cycle and 10th cycle, the elongation between the 10th cycle and 200th cycle, the mean stiffness at the 10th cycle, and the mean stiffness at the 190th cycle. No significant differences were noted between Group 1 and Group 2 concerning the ultimate load-to-failure.
  
  
  CONCLUSIONS
  This study showed that both suture methods appear to be biomechanically effective in a porcine tendon model. However, the single-knot grasping technique (MRH) provided superior biomechanical properties compared with the MFT technique.
authors: Department of Orthopaedic Surgery, University of Palermo (DiChirOnS), Via del Vespro, Palermo, Italy. lawrence.camarda@unipa.it.
authors: Lawrence
authors: L
authors: Camarda
authors: Dipartimento di Ingegneria Chimica, Gestionale, Informatica e Meccanica (DICGIM), University of Palermo, Viale delle Scienze, Palermo, Italy.
authors: Giuseppe
authors: G
authors: Pitarresi
authors: Department of Orthopaedic Surgery, University of Palermo (DiChirOnS), Via del Vespro, Palermo, Italy.
authors: Federico
authors: F
authors: Fazzari
authors: Faculty of Engineering and Architecture, Kore University of Enna, Enna, Italy.
authors: Davide
authors: D
authors: Tumino
authors: Department of Orthopaedic Surgery, University of Palermo (DiChirOnS), Via del Vespro, Palermo, Italy.
authors: Michele
authors: M
authors: D'Arienzo
mesh_terms: D000818:Animals; D005383:Finger Injuries / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D013536:Suture Techniques / Q000295:instrumentation*; D013537:Sutures; D013552:Swine; D013710:Tendons / Q000601:surgery*
keywords: Biomechanics grasping suture; FiberWire suture; Grasping suture; Modified finger-trap; Rolling-hitch; Suture ligament