Biomechanical Study of Asymmetric Flexor Tendon Repair Using a 6-Strand 4-0 Supramid Suture Versus a 4-Strand 2-0...

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Tendon Healing

Background:

• Multi-strand flexor tendon repairs enhance strength but risk ischemia.
• Advanced suture materials may allow for reduced core sutures without compromising repair integrity.

Purpose of the Study:

• To compare the cyclic loading strength of a modified 4-strand Asymmetric repair with 2-0 Tenoflex® suture against the original 6-strand Asymmetric repair using 4-0 Supramid® suture.
• To evaluate if a reduced number of core sutures can be achieved with advanced suture materials.

Main Methods:

• Two groups of 10 porcine tendons each underwent Asymmetric repair: one with 6-strand 4-0 Supramid® and another with 4-strand 2-0 Tenoflex®.
• Repaired tendons were subjected to two-stage cyclic loading tests to analyze survival rate and gap formation.
• Failure mechanisms and suture cross-sectional areas were also assessed.

Main Results:

• The 4-strand repair demonstrated higher survival rates (100% and 60%) compared to the 6-strand repair (90% and 30%) across both loading stages.
• Mean gap formation at stage 2 was comparable between the 4-strand (1.79 mm) and 6-strand (1.82 mm) repairs.
• The cross-sectional areas of 2-0 Tenoflex® (0.078 mm²) and 4-0 Supramid® (0.086 mm²) sutures were similar.

Conclusions:

• The modified 4-strand Asymmetric repair using 2-0 Tenoflex® suture presents a potentially superior alternative to the original 6-strand repair.
• Reducing the number of core sutures with advanced materials like Tenoflex® may improve flexor tendon repair outcomes.