An ex vivo biomechanical study comparing strength characteristics of a new technique with the three-loop pulley for equine tenorrhaphy.

The research article looks into the tensile strength of various suture material and pattern combinations during equine tendon repair. The highlights reveal that a modified 10-strand Savage core suture technique demonstrates superior strength, in both presence and absence of an epitenon suture, in comparison to a 3-loop pulley technique.

Research Methodology

• The study was an ‘ex vivo’ mechanical experiment, which means it was conducted outside of a living body. Instead, superficial digital flexor (SDF) tendons were harvested from adult Thoroughbred and Standardbred horses of mixed age and gender.
• The focus was on 6 different suture material and pattern combinations. These patterns included 10-strand Savage sutures as standalone and paired with Lin-locking epitenon sutures, using either polydioxanone (PDS) or polyglactin 910 (PG910) materials. There were also two examples of the 3-loop pulley type, using each material.

Testing Process and Measurements

• The key characteristics measured for these combinations included their maximum load at failure (measured in Newtons), their gap at failure (in millimeters), and the mode of failure (whether the suture broke or pulled through).
• This data was then subjected to statistical analysis to examine significant differences and interactions between these measured characteristics.

Findings of the Study

• The 10-strand Savage technique’s mean failure load was 872 N, while the same technique with Lin-locking revealed a greater mean load of 998 N at failure.
• Contrastingly, the 3-loop pulley’s mean failure load was significantly less at 337 N.
• Interactions between the technique used and the type of suture material were significant. The 10-strand Savage technique was stronger with the use of PG 910 whereas PDS proved to be stronger for the 3-loop pulley technique.

Conclusions Drawn

• The 10-strand Savage technique, with or without the epitenon suture, was shown to have superior strength characteristics compared to the 3-loop pulley procedure during repair of transected cadaver SDF tendons.
• Suture material and pattern interactions varied, with PG 910 giving higher strength for the 10-strand Savage, while PDS was stronger for the 3-loop pulley pattern.