In vitro biomechanical comparison of clamped suture knot techniques as a model of extra-capsular stabilization of canine cruciate ligament repair

Six clamped suture knot techniques were compared to identify the effects on the biomechanic properties used as a model of extra-capsular stabilization. Six clamped suture knot techniques included square knot formed by clamping the first throw with toothed mosquito forceps (SQ-TM), non-toothed mosquito forceps (SQ-NTM), or needle holder (SQ-NH) and surgeon's knot formed by clamping the first throw with toothed mosquito forceps (SG-TM), non-toothed mosquito forceps (SG-NTM), or needle holder (SG-NH). Monotonic loading test was performed on each suture-loop. Initial loop tension, ultimate load, load at 3 mm elongation, elongation at failure, stiffness, and failure mode were compared among techniques. Clamping with NTM or NH achieved greater initial loop tension than clamping with TM when tying SQ (P < 0.05), whereas clamping with NH led to more loosening of the loops than clamping with NTM when tying SG (P < 0.05). SG-NTM had the highest ultimate load (P < 0.05). In failure mode, the possibility of knot slippage was six times more likely to occur in SQ than SG (P < 0.05). In conclusion, SG resulted in less knot slippage and NTM was able to maintain initial loop tension more effectively. SG-NTM technique is expected to show less risk of suture failure and better clinical outcomes.