Anatomy of the Equine 2014
The abnormal stance of a laminitic horse can lead to many problems. The improper weight distribution on the hooves causes them to distort and grow inappropriately. The back becomes sore and the muscles tighten.
Laminitis is relatively common in horses. There are countless reasons that a horse may
suffer mild to severe inflammation in the laminae and solar coriums. Carbohydrate overload, infections, concussion on hard surfaces, and diseases such as Cushing’s and Insulin Resistance are just a few. Very mild cases can be easily missed because the horse may show little to no symptoms.
In the recent past, it was assumed a horse with laminitis would be standing in the textbook ‘founder stance’: front feet stretched out awkwardly, head down, back arched and clearly in pain.
Today, thanks to new research and lots of educational resources, horse owners are more aware that there are subtle hints a horse is in trouble long before he crashes into a full-blown episode of laminitis.
Owners are the first line of defense in identifying laminitis. It is imperative to know that prognosis is very good if laminitis is caught early. If quick action is taken to prevent internal damage, a horse can easily recover within a few short weeks.
Owners should pay attention to subtle lamenesses and learn to check for bounding digital pulses. Being proactive and alert is the best way to prevent the pain and sorrow of a chronically foundered horse.
IS YOUR HORSE AT RISK?
Metabolic issues are the most frequent cause of laminitis. The two most common metabolic problems are insulin resistance and Cushing’s disease.
Insulin Resistance – cells do not respond properly to insulin
- Horse is overweight
- Insatiable appetite; horses with insulin resistance are abnormally hungry
- Laminitis especially with carbohydrate overload such as spring grass
Cushing’s disease - disorder of the pituitary gland
- Muscle loss across the topline; this contributes to a pot belly appearance
- Increased drinking and urination
- Suppressed immunity which increases susceptibility to infections of all kinds (i.e., rain rot, thrush, scratches, allergies and internal parasites)
- Abnormal sweating or failure to sweat
- Late summer, fall or winter laminitis
- Changes in coat such as a heavy winter coat, slow or very little shedding, and wavy or curling of the hair.
THE BEST TREATMENT APPROACH
To properly treat and manage a horse suffering from laminitis, it is very important to identify the cause of laminitis. For example, laminitis caused by insulin resistance requires diligent nutritional intervention, but laminitis caused by Cushing’s disease responds best to medication. The wrong management will result in mediocre results.
Because a horse may suffer from one or both of these metabolic issues, he may need dietary support, medications or a combination. To complicate the issue, it is not always insulin resistance or Cushing’s causing laminitis. Injuries, complications from pregnancy, reaction to steroids, and tick-borne diseases may also cause inflammation within the hoof capsule. To correctly identify the cause, involve the veterinarian.
“If the horse is lame from laminitis, changes have already occurred at the microscopic level” - laminitis researcher, Dr Van Eps
THE PROGRESSION FROM ACUTE TO CHRONIC
The laminae are the connection between the underlying coffin bone and the hoof capsule. There are two layers of laminae within the hoof. One layer is attached to the wall and the other is attached to the coffin bone.
Laminitic feet grow fast and distort quickly because the bond between the hoof wall and bone is not strong and healthy. As the disease progresses, it is common for the coffin bone to lose bone mass (demineralize), remodel (change shape), and reorient. This is the point at which the horse is considered ‘foundered.’
ABNORMAL HOOF GROWTH
The combination of soft-tissue damage and compromised bone means the hooves do not grow normally. It is imperative that the walls not become too long and further challenge the connection between the bone and hoof capsule.
It can be hard for the hoof care provider to keep up with the changes unless the horse is put on a shorter trimming/shoeing cycle. Distorted, over-grown feet can be difficult to trim because the normal landmarks often change radically. Getting x-rays helps the hoof care provider make good trimming decisions and take better care of your horse.
With proper hoof care and control of the laminitic trigger, even horses with a bad case of laminitis can be made comfortable. Those with less damage can recover but need to be watched carefully. Because these horses will be prone to relapses, any evidence of returning problems needs to be taken seriously and addressed immediately.
Foundered horses often suffer from multiple problems extending way above the feet. Maybe the stress from long term pain or the extended use of pain medication sets these horses up for ulcers. It is wise to keep this in mind and consult your veterinarian if the horse shows symptoms.
In an attempt to relieve pain on their sore feet, the horse usually stands with his back raised and the hind legs further under the body than is normal. This creates lots of tension and tight muscles. Long-term, this abnormal posture and lack of movement can cause muscle and skeletal changes. The skeleton of a chronically foundered pony showed arthritic changes and fusion in the lumbar region of the spine.
It is best to support the horse with a team of professionals. A diligent owner, a progressive veterinarian, an experienced hoof care provider and a body worker all have their place in the long-term care of the chronically foundered horse.
Paige Poss is a professional hoof care provider (www.ironfreehoof.com) and educator. Her passion is teaching the practical and applicable aspects of anatomy.
Paige has joined forces with fellow professional, Jenny Edwards (www.all-natural-horse-care.com) to create dissection-based educational material for the professional as well as the dedicated equine owner. One of their most recent projects, Exploring Laminitis 1, uses comparative anatomy dissections to give insight to the devastating effects of chronic laminitis on the hoof: www.anatomy-of-the-equine.com/exploring-laminitis.html