Laminitis, commonly known as founder, is an issue of prime concern to all horse owners. Founder can be a devastating disease which has the capability of crippling a horse or ruining its athletic capabilities. Approximately 15% of all horses will be suffering from founder at some point in their lives. Laminitis is inflammation of the soft tissues connecting the coffin bone to the hoof wall known as laminae. The laminae can become inflamed for various reasons resulting in excruciating pain in the foot.
Horses of all ages and breeds are susceptible to developing laminitis, although, it is very rare in foals. The exact disease process is not completely understood to date and a subject of much debate. There are three possible theories. The first theory implies decreased blood flow to the coffin bone and laminea. This could be seen in colic horses or grain and lush grass overload. The second theory is that laminitis can also be due to mechanical or traumatic origin, such as cart horses trotting on hard surfaces for extended periods of time. Founder can also be to metabolic reasons, whereby, toxins are released resulting in increased blood flow to the digits as a result of a retained placenta for example. The end result of all these theories is loss of structural integrity of the laminea.
Acute laminits is severely painful. These horses will often have both front feet affected to varying degrees and may be affected on all 4 feet. The patient is often unwilling to move and has a “rocked back” stance, in attempt to take the weight off of the front feet. They may walk with an exaggerated movement in their forelimbs and have a shifting leg lameness when standing. Initially, these horses will have a high heart rate, sweat, and show anxiety due to the pain. Chronically foundered horses may not show the obvious signs. They will often stand with their forelimbs held in front of them. They may have a bulge in their sole and a depression that you can feel at their coronary band.
Diagnosis of laminitis is made through a complete lameness exam by a veterinarian. Foundered horses are sensitive to hoof testers over the hoof wall, especially on the very front toes. The veterinarian will often be able to feel bounding digital pulses on the affected limbs. Nerve blocks may be necessary to determine with certainty that the lameness is located in the laminea of the foot. X-rays of the foot are often indicated to determine if and to what extent the coffin bone has rotated, a progression of the severe disease. This is important to do in order to establish a complete diagnosis and prognosis. Other possible diagnoses for similar lamenesses include hoof abscesses, navicular syndrome, tying up, and neurological diseases.
Treating acute laminitis is an emergency! If caught early enough and treated appropriately, it is possible to save the foot before rotation of the coffin bone occurs and therefore saving the horse’s athletic career! If the cause of founder is known, they should be removed from that source, such as grain, lush green grass, or retained placenta. In cases of grain overload, lavaging the stomach to rid the stomach of grain may be necessary. Starting on a Non-Steroidal Anti-Inflammatory drug, such as Phenylbutazone or Banamine is imperative to treat any type of founder. In acute cases, soaking the feet in cold water or even ice may be necessary. These patients need to be placed in deep bedding with limited movement. They may require corrective shoeing to fix any underlying conformation issues or to place “Lilly Pads” to support and protect the sole.
If you have any questions regarding the above information or any questions/concerns in general, please contact Twin Valley VHS at 745-6642.
Dr. Justin Noble DVM
Twin Valley Veterinary Health Services