The strength of distal fixation of flexor digitorum profundus tendon grafts in human cadavers.

Abstract

Early active motion limits adhesion formation and thus improves functional performance after tendon grafting. The early strength of distal fixation is critical to successful tendon grafting. We describe a new Y-tunnel technique of distal fixation and compare it with 2 established methods, the Pulvertaft transverse tunnel and the Bunnell button over the fingernail techniques, in a human cadaver model to determine which is the strongest method. Hands with a grafted tendon were rigidly mounted on an anatomic tensiometer testing apparatus and loaded to failure. Mean load to failure (newtons +/- 95% confidence intervals) of the Y-tunnel technique (155.2 +/- 29.4) was greater than those for the Pulvertaft (100.2 +/- 13.2) and Bunnell (57.1 +/- 4.7) techniques. Two-way analysis of variance showed significant differences, and the Bonferroni multiple pairwise comparison test showed that all 3 intergroup comparisons were statistically significant. These results indicate marked improvement in immediate strength with the Y-tunnel technique and lay the groundwork for further studies using a healing tendon model.