| Laminitis is a devastating condition of the feet in horses that causes severe pain and debilitating lameness. Laminitis (or "Founder") is a condition of the interdigitations, or lamina, that connect the hoof capsule to the bones of the foot. The exact cause of laminitis is still controversial, but it appears to be caused by conditions that promote vascular or inflammatory changes within the dense network of blood vessels in the foot. Once the connections between the hoof capsule and the foot are damaged, the bone starts to rotate down and away from the hoof wall causing severe pain as the coffin bone impacts on the sole of the hoof. Laminitis can be a primary disease, associated with the overeating of grain or fresh grass or, more commonly, it occurs as a complication of another disorder. These diseases include diarrhea or colic episodes, severe pneumonia or pleuritis, or a condition called Cushing's disease, where a tumor affecting the pituitary gland causes the overproduction of a hormone called cortisol. Laminitis usually affects both forefeet but it can affect all 4 feet at once. Laminitis can also occur in only one foot when a horse has a severe injury such as a fracture in the opposite limb and is bearing most of the weight on one forelimb. Signs of laminitis include: If your veterinarian suspects laminitis is affecting your horse, he/she will take radiographs of your horse's feet to see whether rotation of the coffin bone has occurred. Medical Treatments for laminitis include: Once the initial episode of laminitis is over, many horses have continued pain and lameness due to the pain of rotation of the coffin bone within the hoof capsule. Due to the damage of the laminar connections between hoof capsule and foot, the pressure from standing and the pull of the deep digital flexor tendon that attaches to the bottom of the coffin bone will cause the rotation of the bone within the hoof to increase and pain to persist. One surgical procedure that is used in our hospital to try to stop the rotation and pain associated with laminitis is the Deep Digital Flexor Tenotomy. This is a salvage procedure but for many horses affected with laminitis and rotation of the coffin bone, the persistent pain associated with standing and walking is tremendous. The theory behind this procedure is that by cutting the deep digital flexor tendon the constant pull of this tendon on the coffin bone is stopped, therefore decreasing the pain and allowing the lamina to re-grow in a more normal orientation. The procedure can be done on the standing horse, with sedation and local anesthesia. A small incision is made on the outside of the leg and the tendon isolated and transected with an instrument called a bistoury. The skin incision is sutured and a pressure wrap applied to the leg. A special shoe with a heel extension is placed on the foot to stabilize it. The horse is kept on stall confinement for 8 weeks. The cut ends of the tendon will eventually heal together, but with scar tissue. With proper trimming, horses that have undergone this procedure can achieve a more normal alignment of the bones of the foot and the hoof capsule, and many are much more comfortable following the procedure. If your horse has chronic laminitis with rotation of the coffin bone, this procedure may benefit your horse. Please discuss the procedure with your veterinarian, and/or have your veterinarian call our office to discuss the procedure and our results in person. |