A Biomechanical Comparison Between Asymmetric Pennington Technique and Conventional Core Suture Techniques: 6-Strand Flexor Tendon Repair

Purpose To evaluate the fatigue strength and gap sizes of the asymmetric Pennington technique compared with 2 conventional 6-strand core suture techniques: the triple-looped suture and the Yoshizu #1. Methods We recorded the fatigue strength (forces × cycles) and gap sizes of a 6-strand flexor tendon repair with different core suture techniques under cyclic loading in 30 porcine tendons. The asymmetric Pennington technique was performed with a Pennington repair of equal suture purchase in the 2 tendon stumps, with the 2 other Pennington repairs shifted by 3 mm, respectively, along the longitudinal axis of the tendon in relation to the first Pennington repair. The triple-looped suture technique was made with triple Tsuge sutures. The Yoshizu #1 technique was performed with a combined Pennington repair (using a double strand) and Tsuge suture. Results The asymmetric Pennington technique showed significantly greater fatigue strength and significantly smaller gaps in comparison to the triple-looped suture and Yoshizu #1 techniques. Conclusions This study demonstrated that the asymmetric Pennington technique generated increased fatigue strength and reduced gap sizes compared with 2 conventional 6-strand core suture techniques, the triple-looped suture and Yoshizu #1. Clinical relevance The asymmetric Pennington technique may permit an early active motion rehabilitation protocol similar to the triple-looped suture and Yoshizu #1 techniques.