Orthopaedic problems in horses can result in the loss of a limb, which is essential to the animal's life. Septic arthritis is a disease that affects both adult horses and foals, the latter being more aggressive and posing a risk to the animal's life. The aim of this book is to report the case of a foal affected by septic arthritis as a result of trauma to the tarsal region, emphasising the importance of immediate clinical care so as not to hinder treatment and improve the patient's prognosis.