Horses can develop a variety of different types of cracks that can occur in their hooves. The specific type of hoof wall crack is named based on its length (complete or incomplete), depth (superficial or deep), site of origin (ground surface or coronary band), location (toe, heel, quarter or bar), and whether an infection or hemorrhage is apparent.

• Complete cracks: Cracks which extend the full length of the hoof, from ground surface to coronary band or vice versa.
• Incomplete crack: Cracks which do not extend from end to end of the hoof. These types of cracks rarely cause lameness, unless there is a secondary infection present.
• Sand cracks: These refer to cracks which originate from the coronary band.
• Grass cracks: These types of cracks originate from the ground surface of the hoof.

Hoof cracks often occur due to a multitude of factors, often in combination, which can include:

• Excessive hoof growth: Usually resulting from extended length of time between farrier visits.
• Environment: Excessively wet or dry conditions
• Nutritional deficiencies: Biotin, Amino acids, Selenium
• Genetics: Some horses are more prone to hoof problems than others.
• Improperly balanced hoof: This is usually the result of the work resulting from a poor quality or inexperienced farrier.

The type of treatment prescribed depends on the extend and type of the crack and whether an infection and/or lameness is present.