
Tendons connect muscle to bone and play either a positional role, by maintaining a limb in place under little load, or an energy-storing role during locomotion, by absorbing and releasing strain energy under large load. In the equine and bovine models the two tendon types have different mechanical properties, average collagen fibril diameter and types of intrafibrillar crosslinks. Here I will present tensile testing to failure using an atomic force microscope (AFM) of Collagen fibrils released from the common digital extensor (positional tendon) and the superficial digital flexor (energy-storing tendon) of the bovine forelimb. Imaging the fibrils after failure using AFM and second harmonic generation microscopy reveals that extensor fibril are more prone to plastic damage compared to their flexor counterparts. I will discuss the implications of these results on the molecular packing of collagen within fibrils using a liquid crystal inspired model.

Tendons connect muscle to bone and play either a positional role, by maintaining a limb in place under little load, or an energy-storing role during locomotion, by absorbing and releasing strain energy under large load. In the equine and bovine models the two tendon types have different mechanical properties, average collagen fibril diameter and types of intrafibrillar crosslinks. Here I will present tensile testing to failure using an atomic force microscope (AFM) of Collagen fibrils released from the common digital extensor (positional tendon) and the superficial digital flexor (energy-storing tendon) of the bovine forelimb. Imaging the fibrils after failure using AFM and second harmonic generation microscopy reveals that extensor fibril are more prone to plastic damage compared to their flexor counterparts. I will discuss the implications of these results on the molecular packing of collagen within fibrils using a liquid crystal inspired model.