Porcine tendons as surrogates for human semitendinosus tendons - A biomechanical study

Porcine tendons are frequently used as surrogates for human semitendinosus tendons in biomechanical studies, yet their comparability remains unexplored.

This study evaluates and compares the morphological and biomechanical properties of different porcine tendons (foreleg-extensors (n = 10), foreleg-flexors (n = 10), hindleg-extensors (n = 10) and hindleg-flexors (n = 10)) with those of human semitendinosus tendons (n = 13). Tendon length and cross-sectional area were measured, and maximum load, tensile strength, stiffness, and elastic modulus were determined using uniaxial testing. Statistical analysis was performed using the Kruskal-Wallis test followed by Dunn's post hoc test.

Human semitendinosus tendons (26.59 cm, 18.98 mm²) exhibited the highest tensile strength (38.64 MPa) and an elastic modulus of 518.27 MPa. Porcine foreleg-extensors had comparable cross-sectional area (14.99 mm²), tensile strength (32.26 MPa), and elastic modulus (550.96 MPa) but were shorter (23.08 cm). Hindleg-flexors showed a similar length (25.81 cm) and elastic modulus (610.19 MPa) but lower tensile strength (28.13 MPa) and a substantially larger cross-sectional area (71.91 mm²). Hindleg-extensors were shorter (22.62 cm) with smaller cross-sectional area (11.20 mm²) but exhibited tensile strength (38.82 MPa) and elastic modulus (668.83 MPa) similar to those of the human tendons. Foreleg-flexors were shortest (17.07 cm), with the largest cross-sectional area (112.74 mm²), lowest tensile strength (18.82 MPa), and elastic modulus (155.70 MPa).

Despite differences in morphology, the material properties of tendons were largely consistent. Foreleg-extensors were identified as the most suitable semitendinosus surrogates due to their comparable material and morphological properties. Due to their distinct morphology, foreleg-flexors tendons are least suitable.