Laminitis

Show condition or just overweight?

Feeding for show condition can be a very controversial topic and when it goes wrong it can have disastrous consequences in the form of crippling laminitis. These four horses may all be in show condition or they may be grounded with laminitis.

Q: Can you guess which if any are affected by the condition?

A: See video 1 at the end of the article.

Radiography

X-ray of a normal hoof

Why take x-rays of the feet?

X-rays are essential to visualise what is going on inside the hoof. In a normal hoof the dorsal hoof wall should run parallel with the dorsal aspect of the pedal bone. When taking x-rays vets often place a metal bar on the hoof wall to enable the angle of the hoof wall to be seen compared to the pedal bone. The hoof wouldn’t otherwise show up well on x-ray.

A drawing pin has been placed at the point of the frog on the sole to give us its position on the x-ray.

What common changes do you see in laminitis?

• Pedal bone rotation
• Excessively long toe
• Gas shadows seen on x-ray due to laminar separation (seedy toe)
• Pedal bone sinkage
• Remodelling of the pedal bone at the toe can make it resemble a bird’s beak

Left image shows acute laminitis and seedy toe – the pedal bone has rotated and you can see a gas line where laminar separation has occurred, which appears black in the hoof wall above the first nail in the picture.

Right image shows chronic laminitis with seedy toe – there is inspissated pus within the gas line that shows up in white on the x-ray and extends half way up the dorsal hoof wall.

These images clearly show the rotation of the pedal bone – the bone should be parallel to the hoof wall as shown with the metal marker.

The image on the left shows that the pedal bone has rotated by over 18 degrees from where it should be sitting.

The image on the right clearly shows the pedal bone resembles a bird’s beak which suggests the condition is chronic rather than acute.

Management of laminitis

• Pain relief
• Corrective farriery, trimming and frog supports
• Husbandry

• Bedding
• Feeding high fibre and low sugar, carbohydrate and fructan diet
• Strip grazing and grazing muzzles

• Treatment of underlying factors such as cushings

Prevention

• Maintaining a body condition score appropriate to the breed, age and workload of the horse
• Limited grazing
• Regular farriery
• Be aware of weather and seasonal grass growth that will put your pony at risk
• Aim for fitness, not fatness!

With the correct management there can be light at the end of the tunnel…

This is the horse whose x-rays revealed an angle of rotation of more than 18 degrees and the bird’s beak pedal bone…