Laminitis and Founder
These two should not be confused but they are related and very complex. Laminitis is simply the inflammation of the laminae. Laminae are interlocking finger like tissue that connects the hoof wall to the coffin bone. The laminae is further broken down into the epidermal laminae that is produced at the coronet and is part of the hoof wall and the dermal laminae that actually connects to the coffin bone. The inflammation is enclosed in this hoof capsule that has limited expansion. The inflammation damages or destroys the laminae as the circulation has been compromised.
Causes of laminitis can be from sudden changes in feed, environment, weather, dewormers, vaccines, metabolic issues, etc. Eliminating the cause of the laminitis is essential for damage control and a good prognosis.
Founder is very scary for an owner to go through. I encourage all owners to arm themselves with knowledge. Seek out hoof professionals (farrier or trimmer) you trust and the opinions that make sense to you. If it doesn't make sense, get more opinions. The internet is a good and bad place for information. Recommended sites are located on my resource page. Stay away from blogs and chat rooms. One person's experience may sound like what you are going through but chances are they are not.
This is 3 1/2 months after onset of severe lameness. Initially she was obese and living on a grass pasture. She is rotated 9 degrees. Now you can see new growth, strong attachments. She is about 95% sound in this picture. She runs on occasion with her herd mates with a little hesitation. She now has a slow feeder hay net, muzzle for grass turnout, and has lost a large amount of weight. Her owner is starting very limited exercise in hand to help with weight loss. Her toes were long to begin with. This is remarkable progress for her. She has worn Easy Boot Rx and Epic during her recovery. Go Tess go!
Foundering horses don't need 'therapeutic shoes', stall rest, or drugs that overload the system. Pain management with medications such as phenylbutazone (bute) is helpful but can overload the digestive system and liver as it is processed, placing further strain on an already strained system. Routine use of bute is controversial. It doesn't stop laminitis but it does mask the symptoms. Pain can be stressful for horse and owner but it serves an important role. It keeps them from moving too much and further damaging the laminae. However, they do need to move (movement with hoof support and protection only). Movement stimulates blood flow and brings healthy oxygenated blood to the area. However, do not force walk a lame horse. That would be cruel and completely unnecessary. I am promoting movement that the horse is willing and able to do. Horses can be encouraged to lie down and let the laminae rest to help heal.
Shoeing recommendations range from rocker toed shoes with frog pads or wedge pads, eggbars, heartbars or backward placed shoes. While these provide relief are they necessary? Simple measures of trimming, boots with pads, movement, and controlled diet can dramatically help foundered horses. I feel the horse can heal without us panicking and throwing everything we have in the toolbox at them. Toolboxes are great but sometimes for a project we don't need to use all the tools in it.
To share a personal experience... I have 4 horses, Lady, Zoe, Jack, and Diva. I had 2 kinds of dewormers, two of each. Zoe and Diva received dewormer #1 and Lady and Jack received dewormer #2. They are all on the same feed, in the same pasture, and there were no changes otherwise. They were given the dewormer in the evening. By the following morning (only 12 hours later) Diva and Zoe could barely walk. Ice water soaks were initiated for 20 minutes 2-3 times daily. Anti-inflammatories were given. Boots with pads for support and cushion were immediately put on. Stall rest was necessary as the only turn-out was on grass, and that is a BIG NO for laminitis. They were hand walked three times daily for 45 minutes each. Within 48 hours they were 95% better. After 1 week they were sound. However, the changes from that one event could be seen in their hooves for 9-11 months afterwards.
This is a lucky case as we knew the insult and it was just a matter of time for the body to process it out to have the horses back to normal. Some horses aren't as lucky. The insult isn't removed fast enough and acute laminitis can turn into chronic laminitis. Worst case is these horses with laminitis can founder.
Founder is where the lamellar attachments have actually torn away from the coffin bone and the coffin bone has dropped to apply pressure to the sole corium. This is EXTREMELY painful. Horses should be supported in special boots modified just for them to support the bottom of the hoof and provide support to the sole and frog. The circumflex artery wraps around the distal perimeter of the coffin bone; when the coffin bone drops the pressure can pinch off blood supply and reduce the ability of sole corium to grow. This presure and damages it causes can also lead to abscesses. These situations require serious diet, environment changes, and owner commitment for rehabilitation. Where not all cases of founder can be reversed, a vast majority of them can be reversed with aggressive and immediate action. I feel that owner, trimmer, and veterinarian need to be working together to make the best decisions for that horse.
Founder can further be described as a 'sinker' or 'rotation'. A sinker can be extremely difficult to rehabilitate as the entire laminae has 'let go' of the coffin bone, there is no remaining lamellar connection. There will be a depression around the entire coronet band a little bigger than pea size. A rotation is where the toe of the coffin bone has rotated down and applies pressure to the sole corium. There is so much pressure from this that the coffin bone can penetrate the sole. Boots and pads are a must to support the coffin bone and sole. Most of the detached laminae is located in the toe and the laminae is still attached at the quarters.
Founder can be a result of laminitis where the inflammation has damaged the lamellar attachments but it can also be mechanical. Mechanical founder is from repeated external forces that weaken and damage the laminae. You see this kind of founder on shod horses, unkept horses, and horses that work on pavement for a living.
