Corns
Introduction
A ‘corn’ is bruising of the sole in the angle between the medial hoof wall and the bar (the ‘seat of corn’). The bruising is usually present on the medial side of the fore feet.
Signalment
'Corns' can affect any age, breed or sex of horse as they are usually caused by badly fitting shoes. This can occur if shoes are too small, when the branches will lie over the ‘seat of corn’ and will result in bruising of this region. Alternatively, correctly fitting shoes which are left in place for long periods will move to cover this sensitive area as the foot grows. Horses with thin soles or poor foot conformation may be more prone to developing 'corns'.
Clinical Signs
The bruising may be visible on the sole after paring down the hoof. It normally occurs on the medial side of the fore feet. The horse will normally test positive to hoof testers over this region. The horse will normally present with a low-grade lameness. Lameness will be more severe when loading of the bruised area is greatest and, in the case of the medial side, this will be when the affected limb is on the outside of the circle.
Treatment
- The badly fitting shoe should be removed, and the affected area pared out.
- Paring should be halted once the bruised area is identified.
- If the ‘corn’ has become infected, paring should be continued to establish drainage (as for a solar abscess).
- The foot can be left for a few days for the bruising to heal and the horse to become sound.
- When shoes are re-applied, care must be taken to avoid pressure in this region – shoes can have the caudal end of the medial branch seated out, and in some cases the heel widened so that it covers and protects the affected area while still being supported by the wall.
Prevention
Good hoof care and regularly changed, well-fitting shoes.
References
May, SA & McIlwraith, CW (1998) Equine Orthopaedics and Rheumatology Self-Assessment Colour Review Manson Publishing Ltd
Captain M. Horace Hays FRCVS Veterinary Notes for Horse Owners (Revised Edition), Stanley Paul
Merck & Co (2009) The Merck Veterinary Manual (Ninth Edition), Merial