Laminitis is inflammation of the lamina: the bond between the hoof wall and the coffin bone. This bond is the only thing that prevents your horse’s body weight from forcing the coffin bone through the sole of the foot.
What causes it?
The abundant nerve and blood supply make the lamina very susceptible to injury and disease. Common primary causes of laminitis are grain overload, ingestion of lush grass and severe illness (critical colics, colitis, pleuropneumonia, retained placentas in mare, etc). Other horses that commonly develop laminitis are those with Cushing’s disease or Equine Metabolic Syndrome (usually due to the horse being overweight).
What signs should you look for?
The clinical signs depend on the severity of the disease. The most common sign is lameness ranging in severity from a minor head nod to non-weight bearing lameness. The horse may develop a “saw-horse stance” which looks like your horse is walking on eggshells. Laminitis is most commonly seen in the front limbs but can be seen in all four limbs, especially if your horse is systemically sick.
How do you diagnose laminitis?
A diagnosis of laminitis is based on clinical signs and radiographs (x-rays). Radiographic changes include: change in the density of the coffin bone, rotation of the coffin bone away from the hoof wall, sinking of the coffin bone and destruction of the coffin bone in severe cases. In the very acute phase of laminitis, radiographic changes may not be evident. However, radiographs are very important to obtain when signs of laminitis begin in order to track any progression of the disease.
Treatment/management plan:
Treating the laminitic horse is largely dependent on the phase of disease: acute vs chronic. In the acute phase of laminitis, reducing the load on the inflamed lamina is paramount. This can be achieved with keeping your horse in a confined space (stall or small paddock) with deep bedding (shavings or sand). Another important feature of treating acute laminitis is the implementation of pain medication. Nonsteroidal anti-inflammatories (NSAIDs) such as Bute or Banamine generally provide effective pain control in acute laminitis. If NSAIDs are not sufficient enough to manage pain, other medications may also be concurrently administered (opioids, lidocaine and/or Gabapentin). If your horse develops acute laminitis due to a concurrent ailment (colitis, critical colic, uncontrolled Cushing’s or obesity due to metabolic syndrome), it is important to control the primary disease to help prevent progression of laminitis.
Management of a horse with chronic laminitis (horse with radiographic evidence of rotation of the coffin bone) is multifactorial and vital in prevention of progression of rotation of the coffin bone. Some of the mainstay treatments of acute laminitis (pain management and controlling concurrent disease) hold true for management of chronic laminitis. Horses in the chronic phase are usually more comfortable and may need a less potent pain medication. Once appropriate comfort is achieved, exercise should be slowly reintroduced. Horses with chronic laminitis may never be able to go back to their previous workload, but could be sound enough for light riding and exercise.
Diet changes are important in the management of a chronically laminitic horse. The recommended diet is low in readily digestible starches and carbohydrates. Teff hay or low-starch pelleted feeds tend to be safe. However, to be entirely certain of the carbohydrate/sugar content, your hay would need to be sent in for analysis every time a new batch is purchased. A diet that consists of lower quality hay is likely marginal in vitamin and mineral content, so it is important to add a ration balancer to your horse’s diet to ensure their daily requirements are met.
Lastly, good communication between you, your farrier and your veterinarian is important to ensure that your horse is appropriately trimmed and shod based on any radiographic changes to the coffin bone. Overall, frequent assessments of your horse and communication with your veterinarian is key to the management of the laminitic horse. While having a chronically laminitic horse takes commitment and may be disheartening at times, these cases can be managed and your treatment team is always here to support you!
References
1) “Large Animal Topics.” Laminitis in Horses | ACVS,
www.acvs.org/large-animal/laminitis-horses.
2) Orsini, J. A., et al. (2010). “Home care for horses with chronic laminitis.” Vet Clin North Am Equine Pract 26(1): 215-223.
3) van Eps, A. W. (2010). “Acute laminitis: medical and supportive therapy.” Vet Clin North Am Equine Pract 26(1): 103-114.
