Why do horses get hoof abscesses and how are they treated?

cases. 
Is it always that easy?
Usually horses respond very well to abscess drainage and are soon back to full health however some cases can be more complicated. If the horse continues to be lame or there are recurrent episodes then radiography Xraying is recommended to assess the structures within the hoof. Sometimes a deep infection can occur affecting the pedal bone or the soft tissues around it.
This can be very difficult to treat and some of the hoof wall may need to be cut away to improve the chance of successful treatment. A tumour called a keratoma can develop in the pedal bone which can result in persistent or recurrent foot abscesses seen as a dark circular area on an xray image again the hoof wall would need to be pared away so that the pedal bone could be treated appropriately otherwise the condition will persist. Other causes of foot pain include bruising of the sole laminitis or a fracture of the pedal bone and radiography can be used to distinguish between these conditions.
Make sure theyre vaccinated
Tetanus is a bacteria found in the soil that can infect a horse through a wound in the skin or hoof wall. It is important that your horse is vaccinated against Tetanus because the infection can be fatal. If the horse hasnt been vaccinated an antitoxin injection may be given as a precaution but this should be followed up with a vaccination course to ensure that the horse is protected in the future. 
Prevention is better than cure!
Foot abscesses are most commonly seen during the winter months as the ground is wet and muddy this can cause the hooves to become softer making it easier for damage to occur to the foot allowing bacteria to enter. Some horses have thinner soles and therefore may
be more prone to abscesses in these horses a plate or pad can be placed over the sole of the foot to prevent trauma to the foot. Abscesses can also be prevented by carrying out good foot care including daily hoof picking to remove mud and stones and regular foot trimming by the farrier to prevent overgrowths and imbalance.