Corns

Introduction

A ‘corn’ is bruising of the sole in the ‘seat of corn’ (the angle between the medial hoof wall and the bar of the hoof). The most common location for this bruising is 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 a shoe is left on too long; as the hoof grows the shoe begins to sit over the ‘seat of corn’, resulting in bruising of the area. Alternatively, shoes may be too small from the outset and again cause bruising to develop by lying over the 'seat of corn'. 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

1. The shoe should be removed and the sole of the hoof pared out to reveal the bruising.
2. If infection has developed then paring should continue to allow draining of the purulent material.
3. The shoe should be left off for several days to allow the bruising to heal.
4. The shoes can be re-applied when the horse is sound.

To avoid the recurrence of the corn, pressure should be avoided over the region. For example, the caudal end of the medial branch of the shoe can be seated out, in addition the heel can be widened so it covers and protects the affected area.

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