BIOMECHANICAL ANALYSES OF THE HUMAN ACHIL LES-TENDON RUPTURE

The biomechanical properties of human Achilles tendon are described wi th a computer-controlled material-testing machine. With an optimized f ixation device for the muscle-tendon-calcaneus system the rupture was intratendineal. The tendons were compared for different rupture speed (1000 mm/min vs 100 mm/min), sex and age (<35 years vs >35 years). The tendons ruptured at 1000 mm/min had better results in terms of maximu m rupture force, stiffness and tensile stress, while the results for e longation and energy were less good. None of these differences were st atistically significant. Significant differences were found between th e sexes: male tendons had higher maximum rupture force and stiffness a nd a larger cross-sectional area. In the younger tendons significantly higher tensile rupture stress and lower stiffness were found.