Scientists at the University of Liverpool are comparing ancient 15-million-year-old horse fossils with the bones of modern racehorses to find out why horses' legs can be prone to fracture.

Researchers are comparing modern bones with the fossils - using computer models to simulate how the old and new bones would respond to the forces experienced as horses gallop.

Lead researchers Dr Ellen Singer and Dr Nathan Jeffery told BBC News how comparing ancient and modern horses' leg joints could eventually help vets to understand ways in which "catastrophic" fractures might be prevented.

Slow motion footage courtesy of Dr Ellen Singer, University of Liverpool

Video journalist: Victoria Gill