The hoof problem previously known as Hoof Wall Separation Syndrome (HWSS) has been renamed as Hoof Wall Separation Disease (HWSD). HWSD is an unique, verifiable and testable disease. It should not be confused with any other hoof pathology. HWSD is a genetic autosomal recessive condition. Two carrier parents being bred with each other results in 1:4 chance of the foal being HWSD afflicted. There is now a commercially available genetic test for the HWSD mutation.
HWSS: photographs of affected hooves
It is not easy to put multiple pictures up on this site easily.
Therefore follow the link where you will be able to view photographs of hooves with various degrees of HWSS.