The white line is the site at which the horn of the wall of the hoof joins that of the sole. It is a naturally weak area in the horn and cracks can allow dirt and bacteria to enter, causing abscess formation, pain and lameness. The initial weakness in the white line may be a result of laminitis, abnormal conformation and possibly dietary effects. The abscess most commonly occurs on the outside of the outer claw of the hind foot.

This type of lameness is the most common form of lameness in yarded cattle, especially on slats. Excessive activity on poor underfoot surfaces can lead to a high incidence of the condition. Restrictions of trough space in yarded cattle may also predispose the condition.