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One of the speakers at the First International Conference on Laminitis and Diseases of the Foot, held in Florida earlier this year, was Robert Eustace, the director of the Laminitis Clinic in the UK. He reported on the work that he has carried out over the last 12 years in the Laminitis Clinic. He described his approach to the assessment of cases of laminitis, founder and sinkers and the methods he has used to treat them.

First of all he suggested that you should not use the terms laminitis and founder synonymously. He described four groups of cases which could be differentiated on the basis of the signs they showed:

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Treatment of the acute founder and sinker case

Treatment of the Acute Founder

and Sinker case

Laminitis. Affected feet have a stronger digital pulse. Feeling for heat in the feet is not helpful. Lameness may vary from slight to severe, with the animal tending to walk on its heels. Prompt treatment can be expected to give a success rate of 100%.

Acute Founder. In addition to signs of laminitis these cases show a depression in the coronary band at the toe. To assess prognosis, the important feature to look for on radiographs is the "founder distance" (ie the vertical distance between the coronary band and the top of the pedal bone). Measuring angles of rotation is not helpful. A success rate of 82% can be expected overall. The success rate falls dramatically once a founder distance of 15 mm is exceeded.

Sinker. These have a strong digital pulse and are very reluctant to move. They tend not to walk on the heels like the laminitis or acute founder case. The depression at the coronary band extends all the way back to the heel on both sides. These cases have the worst outlook. The expected success rate is only 20%.

Chronic founder. These are cases which have had acute founder previously. Their hooves are abnormally shaped. The heels grow more quickly than the toe, producing long toes with concave front walls. The growth rings on the hoof are more widely spaced at the heels than at the toe. X-ray examination is required to determine which of these cases will respond to treatment. Those which show minimal changes to the pedal bone have a success rate of 78%. Those with significant damage to the pedal bone do not recover.

Assessment of an acute laminitis or founder case

This should include:

assessment of general health. For example, a thin horse is unlikely to have developed laminitis through over-eating, it is usually systemically ill. Blood tests should be taken to establish whether there is any underlying medical cause, and maybe dynamic hormone tests.

radiographic assessment , especially to determine founder distance which has implications for the likely chance of success.

Treatment of laminitis or acute founder.

Eustace emphasised that early treatment was very important. His approach to treatment includes:

Temporary frog support. He places a part roll of bandage along the frog so that the front end lies 1cm behind the trimmed point of the frog. The bandage is taped to the foot with elastic adhesive tape. It is important not to apply the tape too tightly over the coronary band. The thickness of the bandage applied to the frog is adjusted for each foot. The aim is that the horse takes most of his weight on the walls, with a little weight being taken by the frog. In Eustace`s experience 90% of cases are immediately more comfortable after correctly fitting frog supports have been applied. He never applies pressure to the sole.

Medical treatment. Prompt medication is vital. Vasodilators are used - either acepromazine or phenoxybenzamine- to improve the circulation to the laminae. Non-steroidal anti-inflammatory drugs are used to provide pain relief. The aim is to reduce pain , but not abolish it completely. You do not want to encourage the horse to move more than necessary.

Bedding. The horse should be confined to stable rest on a deep bed of clean dry shavings. The horse should be encouraged to lie down. Laminitis cases need a minimum of 30 days complete stable rest. Acute founder and sinkers need 5 - 9 months!

Feeding. High fibre, low calorie diets should be fed. In the UK, suitable diets carry the Laminitis Trust Approval Mark. A supplement to support the liver and thyroid gland function (eg Farriers Formula) should also be given.

Shoeing. The temporary frog supports can be left in place for up to as week., but should be replaced by a glue-on adjustable heart bar shoe as soon as possible.

Abscesses. Some cases develop abscesses under the wall or under the sole. These should not be drained through the horny sole. If they are under the wall it is best to either remove the front wall or drill through it, in acute or old founder cases. If the abscess is under the sole at the back of the foot, the foot should be tubbed to encourage the abscess to burst.

"These methods have led to the highest reported success rates for the treatment of laminitis, founder and sinking" said Eustace.

For more details of the work of the Laminitis Trust and the Laminitis Clinic, contact:

Robert A. Eustace BVSc CertEO CertEP FRCVS

The Laminitis Trust, c/o Mead House Farm, Dauntsey, Chippenham, Wilts SN15 4JA.

or see http://www.laminitisclinic.org/

Report by Mark Andrews. 2002