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

Foot abscesses can be excruciating for horses, in fact, they can make the horse so lame that it can look like the horse has broken his leg! But why do they happen and what can be done about them?

Damage to the hoof capsule from a nail or a stone can allow bacteria to enter the hoof. This bacteria then gets trapped inside as the entrance closes up. Inflammatory cells build up inside this small pocket and with nowhere to go, the pressure inside the foot increases, making the foot extremely painful. The first thing you will notice is lameness, with the foot also being warm to the touch and strong pulses being felt in the pastern area. 

Drainage, drainage, drainage…

Sometimes an abscess will make its way out through a soft area of the foot such as at the heel bulbs or coronary band but often the abscess will need to be cut open to allow drainage, relieving the pressure in the foot. The location of the abscess can be confirmed by your vet, who will use an instrument called a hoof tester to press on the sole of the foot, looking out for any sensitive areas. Once the vet is confident about the site of the abscess, they will use a hoof knife to pare the sole of the foot away, producing a dark smelly discharge. 

To encourage drainage of the abscess, a wet poultice is placed on the foot for several days, being changed daily to check for progress. Once the discharge has stopped, the poultice can be removed but the hole may need to be covered to prevent further contamination from soil or bedding material. A course of anti-inflammatories may be recommended to make your horse feel more comfortable but treatment with antibiotics is not necessary in most 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 (X-raying) 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 x-ray 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 they’re vaccinated…