Sheared heels as a predisposing factor for quarter crack formation in the equine hoof

Summary Full thickness hoof wall defects such as a quarter crack, result in loss of the structural integrity of the hoof wall, are common in equine practice and often manifest in lameness. Many causes of quarter cracks have been described, such as trauma to the coronet, pre‐existing damage to the dermis from infection, abnormal hoof conformation, insufficient length of shoes, inappropriate farrier practices or an abnormal landing pattern when the foot strikes the ground. The most consistent finding in all quarter‐crack cases is a hoof capsule distortion termed a ‘sheared heel’. Successful management of these hoof wall defects involves identifying and addressing the underlying cause(s), stabilisation of the digit and committed follow‐up. Treatment is most successful when the cause is investigated and identified, the appropriate farriery is initiated as early as possible, and when the biomechanical properties of the foot are thoroughly understood. Inadequate attention to these factors may account for the many treatment failures encountered in equine veterinary practice and the recurring nature of a quarter crack.