A puncture in the sole of the hoof by a foreign object such as a nail, piece of wire, or even a sharp stick is a serious situation that should be evaluated by your veterinarian as soon as possible.
When to leave the object in the foot
You do not want to remove the object from your horse’s foot for a number of reasons. First, removing the object will allow the structures in the foot to swell and close off the puncture wound, potentially trapping dirt and bacteria inside the hoof. Second, removing the object will make it harder for your vet to evaluate the potential damage it caused because they are not able to see where exactly the object was. Third, metal objects like nails and roofing tacks can be easily seen with radiographs, which allows your vet to see which structures may have been compromised by the foreign body.
When to remove the object
If the foreign object is not flush with the sole of the hoof, and your horse will drive it further in by taking a step, it is best to remove the object as soon as possible to prevent further damage. Your veterinarian will still need to assess your horse’s condition to ensure all of the foreign material was removed and an appropriate treatment plan is established.
Depending on what type of object your horse stepped on, how long it was there, and which structures were involved, your vet may offer a variety of treatment protocols. In best case scenarios, the object missed important structures, and a wrap and foot soak, along with a tetanus booster, may be all that is needed. For objects that have been in the foot for a while, or damaged important structures, your vet may prescribe a round of antibiotics. In cases where the the coffin bone or a joint is involved, performing a series of regional limb perfusions with intravenous antibiotics may be the best course of treatment.