A biomechanical study of pediatric flexor profundus tendon repair: Comparing the tensile strengths of 3 suture techniques

OBJECTIVES: To investigate the tensile strength of repaired flexor profundus tendons in young lambs, which would be equivalent to repairs in children older than 2 years of age. METHODS: A comparative in-vitro experimental study conducted at King Saud University, Riyadh, Kingdom of Saudi Arabia from October 2014 to December 2015. We utilized 30 flexor profundus tendons of young lambs with a width of 4 mm. All tendons were repaired with a 4-strand repair technique using 4/0 polypropylene core sutures. In group I (n=10 tendons), 2 separate figure-of-eight sutures were applied. In group II (n=10 tendons), simple locking sutures were added to the corners of 2 separate figure-of-eight sutures. In group III (n=10 tendons), the locked cruciate repair was used. All tendon repairs were tested to single-cycle tensile failure. RESULTS: There was no significant difference between groups II and III with regards to gap and breaking forces; and all forces of these 2 groups were significantly higher than the forces in group I. CONCLUSION: It was concluded that 4 mm-wide pediatric flexor tendons allow a 4-strand repair and the use of 4/0 sutures. The use of locking sutures increases the tensile strength to values that may allow protective mobilization in children.