Reinforcement of the Flexor Tendon Repair Using Human Amniotic Membrane

Abstract

Human amniotic membrane is used to prevent peritendinous adhesions after tendon injuries. This study compares the mechanical properties of modified Kessler repairs and modified Kessler repairs strengthened using multiple layers of human amniotic membrane. Twenty flexor digitorum profundus tendons of sheep forelimbs were sutured by the two-strand modified Kessler technique (group A) and by the two-strand modified Kessler repair reinforced with multiple layers of human amniotic membrane (group B). To assess the mechanical performance of the repairs, tendons were subjected to a linear noncyclic load-to-failure test using a material testing machine. Outcome measures included ultimate forces and the mode of failure. The mean ± SD value of the failure strength was 34.6 ± 1.64 N for group A and 50.6 ± 5.60 N for group B. The reinforced repair provided a significantly higher ultimate load compared with the nonreinforced group (P < .001). All of the specimens failed due to suture breakage at the repair site. The results of this study show that the modified Kessler repair can be reinforced effectively with human amniotic membrane.