Truong Thanh Dinh & Thi Cao

The purpose of this study was to describe the applied anatomy of the flexor hallucis longus tendon and evaluate differences between sexes and sides, as well as the influence of foot length. Thirty lower limbs from fifteen Vietnamese cadavers were dissected. Measurements included distances from the master knot of Henry to anatomical landmarks, tendon dimensions, intertendinous slips, branching patterns, and tendon length obtained using different harvesting techniques. The master knot of Henry was located 5.8 cm from the medial malleolus, 2.6 cm from the navicular tuberosity, and 11.8 cm from the interphalangeal joint. The mean distance to the medial plantar neurovascular bundle was 3.8 mm. Slips between the flexor hallucis longus and flexor digitorum longus tendons were Type 1 in 83.3 % and Type 5 in 16.7 % of specimens, and branching patterns were Type 2 in 60 %. Tendon length was 3.8 cm with the single-incision technique, 5.9 cm with the double-incision technique, and 18.0 cm with the minimally invasive technique. Tendon length was significantly greater in males than in females, except for the segment from the musculotendinous junction to the interphalangeal joint, and no differences were observed between sides. The flexor hallucis longus tendon showed consistent anatomical relationships with surrounding landmarks and neurovascular structures, with sex-related differences in tendon length and no significant effect of laterality.

KEY WORDS: Flexor hallucis longus; Tendon transfer; Foot; Flexor digitorum longus; Cadaver.

THANH DINH, T. & CAO, T. Applied anatomy and sex- and side-related differences of the flexor hallucis longus tendon: A cadaveric study. Int. J. Morphol., 44(2):414-419, 2026.