A CADAVER STUDY OF THE FHL AND FDL TENDONS CROSSING – A CONTRIBUTION TO NEGLECTED ACHILLES TENDON RUPTURE SURGERIES

Abstract

Introduction: A.K. Henry described the region of the cross-connection between FHL tendon and FDL tendon in the mid-foot. It had been termed “master knot”. Up to now its description was not done exactly.

Aim: In this study we were investigating the exact structure of the tendons connection and possibilities of the tendons transfer in the region of foot; especially for repairing extended or neglected Achilles ruptures.

Methods: Both feet in 30 cadavers (17 men, 13 women) had been prepared. The distance from proximal part of the knot to the distal insertion of FHL and the distance from the end of FHL origin to the proximal part of the knot had been measured. This values had been compared with the foot length.

Results: In the investigated group of cadavers had not been found any direct junction between FHL and FDL tendons proximally from the branching FDL for fingers. There is an interconnection from the FHL tendon to distal part of FDL for 2nd eventually for 3rd finger (distally from FDL branching). We did not find any connection described in anatomical study of E. O’Sullivan (Clinical Anatomy18: 121 – 125, 2005).

The average distance from the point of interconnection on the FHL to its insertion was 13,8 cm (9,8 cm–19,4 cm), from the end of muscle origin 17,9 cm (15,7 cm–19,6 cm).

The approximate distances after the conversion to the foot length were 0,70 times foot length and 0,55 times foot length.

Conclusions: There is no direct junction between FHL and FDL tendons proximally from the branching FDL for fingers. The suture of the tendons distally from the cut of transferred tendon and proximally from FDL branching is necessary to keep the correct flexion of all fingers.