Laminitis is multi-factorial disease that causes a generalised inflammation of the dermis of the hoof which then may lead to severe structural disruption of the dermal lamella and cause breakdown of the dermal-epidermal junction (the dermal/sensitive lamella separate from the horny/insensitive lamella). This leads to a breakdown of the suspensory apparatus of the coffin bone (distal phalanx), which then causes the bone to change its position within the hoof capsule (rotation/sinking). These inflammatory and structural changes are often associated with a considerable amount of pain and result in high grade lameness.
As the disease is frequently due to systemic factors such as carbohydrate overload or disease associated endotoxemia, all 4 feet may be affected simultaneously.