Corn in Horses

Corn in Horses is a contusion (bruise) of the sensitive laminae at the angle formed between the wall and bars of the hoof. This region of the foot is called seat of corn. A contusion of the sole is known as “Bruised sole” and a contusion on the frog as a “bruised frog”. Corn is more common in the fore limb, mostly on the inner aspect.

Classification of Corn

Corn in Horses is classified in four types-

1. Dry Corn: in this there is only slight capillary bleeding resulting in echymosis or staining of overlying horn
2. Moist corn: in this there is collection of inflammatory exudates beneath the horn and horn appears to be soaked in moisture.
3. Suppurative corn (Festered corn): suppuration is caused when infection gains entrance through any small fissure in horn and pus collects  underneath. The horn appears more or less translucent.
4. Complicated corn: the pus tries to migrate upwards following the line of least resistance, and escapes through small opening at the coronet region. During the course of migration of pus, infection may extend to the plantar aponeurosis, plantar cushion, lateral cartilage, portion of os-pedis, etc. Portion of these structures coming in contact with pus may show partial necrosis.

Etiology

Predisposing causes are faulty conformation of foot like upright walls, turned-in toes, wide, spread foot with low week heels, atrophy of frog, contracted heels, etc.

Exciting causes are bad shoeing is the major exciting cause of corns. Corns are only very rarely seen in unshoed horses.

Symptoms

• Pointing
• Lameness
• Going on toe

Diagnosis

Diagnosis of corn is based of hoof examination-

Hoof is cleaned and carefully examined the seat of the corn. Pain is evinced when seat of the corn is gently tapped with hammer.

The horn at this region may appear moist and translucentIn dry corn, a reddish colouration maybe seen due to the presence of blood collected underneath.

Suppurative corn presents a yellowish, moist appearance because of the pus.

Treatment

• Remove the shoe
• Pare away the horn at the seat of the corn to relieve pressure at this point and use a seated-out shoe.
• Rest is essential
• In the case of suppurative corn a conical portion of horn may be excavated to facilitate drainage of pus.
• Foot bath and antiseptic dressings
• In complicated corn stripping of the wall may be necessary to evacuate the pus.

Prognosis

If treated early, prognosis is favourable. In suppurative corn prognosis is guarded.