Mechanical properties of four suture patterns for transected equine tendon repair.

This research investigates the mechanical properties of four different suture methods used in repairing transected equine tendons with the goal of determining the strongest and most efficient technique. The key finding is that the three-loop pulley suture pattern displayed exceptional strength and resistance to gap formation.

Research Methodology

• The study employed thirty-six superficial digital flexor tendons from nine fresh equine cadavers. These tendons were intentionally transected and then repaired using size 2 monofilament nylon.
• The research team used four different suture patterns to repair the tendons: single-locking loop, double-locking loop, triple-locking loop, and three-loop pulley. Nine tendons were used for each of these suture patterns.
• They measured different properties such as the time required for suture application, tensile strength, resistance to distraction (gap formation), and modes of failure.

Findings

• The time required to apply each suture pattern was varied, with the triple-locking loop taking the longest time (about 10 mins, 50 secs), while the three-loop pulley and double-locking loop requiring less than half of that time.
• In terms of tensile strength, the double-locking loop, triple-locking loop, and three-loop pulley patterns were stronger than the single-locking loop. Among these, the triple-locking loop was only surpassed in strength by the three-loop pulley.
• The three-loop pulley displayed the greatest resistance to gap formation, implying better durability after the repair process.
• The failure modes of these suture patterns were also different. The single, double and triple-locking loop patterns failed due to suture breakage, whereas the three-loop pulley failed first by suture pull-out, and then by breakage.

Implications

• These findings suggest that the three-loop pulley suture pattern could be the most effective for repairing transected equine tendons due to its strength and resistance to gap formation.
• Despite its advantages, the application time for the three-loop pulley is longer than the single and double-locking loops, but significantly less than the triple-locking loop. In cases where time is a critical factor, the double-locking loop could be considered given its relative balance between strength, resistance to gap formation and application time.