Looking backwards to move forward: an in-depth study of physiological and pathological features of the equine vertebral column

Abstract

Like humans, horses can have back pain. Fortunately, humans can verbally communicate with a doctor to specify where and to which extent they have pain. In contrast, horses cannot verbally communicate and are reliant on their caretaker/rider for recognising signs of suspected pain, and the veterinarian’s ability to diagnose the source of pain. During the exam, veterinarians observe how the horse moves, but agreement between veterinarians on what constitutes normal and abnormal movement in horses with back pain, has not been studied. In this thesis, visual examination from several veterinarians and objective (through computer) measurements were compared. Several differences were observed, not only between the veterinarians, but also between the veterinarians and the computer. The results generate serious food for thought, and room for improvement. Computer measurements and wearable sensor technologies were also used to evaluate the impact of lameness on the range of motion and muscle activity of the legs and back of the horse. Differences were noted between forelimb and hind limb lameness. Hindlimb lameness had a larger effect on both back motion and muscle activity, which is important to know when horses with orthopaedic problems are examined. Further in this thesis, anatomical and pathological variations in foals and different horse breeds were examined with computer tomography. These studies show a large variety within and between breeds, which were present in both ridden and unridden populations. Given the horse’s inability to directly communicate with the veterinarian this thesis provides equine veterinarians with new anatomical and biomechanical insights into the equine back. This information can be used to advance understanding and applied in practice to improve the veterinary examination of horses with back problems.