Eithne graduated from the Faculty of Veterinary Medicine, UCD, Ireland in 1995. From 1995-2006, Eithne worked at the University of Bristol, where she was awarded her PhD on the pathogenesis of cranial cruciate ligament disease.

Since 2006, Eithne has worked at the University of Liverpool, becoming Professor of Small Animal Surgery (and Head of Musculoskeletal Biology) in 2014. Her role combines specialist small animal orthopaedics, research, teaching and administration.

Her main clinical interests include minimally invasive joint surgery and cranial cruciate ligament disease (CCLD). In her current role as Head of Musculoskeletal Biology, she manages a team of 18 academics as well as developing her research into the structural changes in human and canine cruciate ligaments with ageing and disease. Eithne was awarded the BSAVA Simon Award in 2017 for her contributions to small animal surgery and for her work into tendon and ligament research.