Pedal osteitis: What you don't know....

Can hurt your horse, especially when it's inside the hoof. This is why you want to get those hooves x-rayed for any persistent/chronic/recurring abscess or foot pain. PO occurs when there is infection or inflammation/bruising in the foot occurring near the coffin bone. The process in the hoof can erode or demineralize the bone, which is officially Not Good.

How Bad Is It?
Well, a horse can lose up to 25% of the pedal bone and still perform athletically. But the process that compromises the bone needs to be stopped. PO is more a symptom than a diagnosis, and the success of the treatment depends on the cause and how readily the cause can be addressed. There are two types of PO: septic and non-septic. They are treated differently.


Septic PO
Septic PO occurs when bacteria or foreign matter penetrates the hoof wall, such as when:

• a horse steps on something like a nail or piece of glass
• a misplaced horse shoe nail provides a conduit for bacteria
  
• bacteria from dirty bedding or mud penetrates protective barriers of the hoof capsule
• a horse kicks in the stall and gets a splinter in his hoof
  

All of these things can cause an infection and/or abscess. Hopefully it'll drain and go away, but sometimes it doesn't drain, or if the foreign matter is not expelled, it drains and recurs. A chronic infection near the bone can cause it to erode/demineralize, or the bone itself can become infected (I'm not sure if the latter case is actually PO).

How is septic PO treated?
The treatment is usually to surgically debride and clean the infected area of the hoof, and/or administer antibiotics through a technique called perfusion ( a tourniquet applied to assist the meds in going into the hoof). Expect a long-ish recovery time for this treatment.

Nonseptic PO
This is what we think Riley has, and thank goodness it was caught very early. Nonseptic PO is bone erosion due to inflammation, but not necessarily bacterial infection. The most common cause of nonseptic PO is repetititve concussion or perhaps a traumatic injury (non-penetrating) that causes bruising. A severe or chronic bruising can result in a hematoma. Dead blood can provide a great "home" for bacteria, which is one area I'm frankly a bit fuzzy on. If there is bacteria, is it non-septic?

Anyhoo, the treatment generally is to stop the trauma or concussion and let the affected tissue grow out. If there is dead bone, or very diseased tissue, surgical debridement may be indicated. What's the prognosis? It depends on how effectively the concussion to the hoof can be reduced or eliminated. If you ride on hard ground, stop! If your horse is barefoot, put shoes on. For a competitive jumper whose career depends on the ability to withstand concussion, there may not be much that can be done. PO can be the end of a career or the beginning of a new, less strenuous career. If the bruise was caused by one-time trauma (e.g., stepping on a stone), the prognosis can be very positive.

Riley
The PO on Riley's radiographs is certainly less than 25% of his bone -- more like 5 or 10%. I'm kicking myself for not putting shoes on Riley. I wanted to buy his feet time to grow and expand in the barefoot tradition. At any rate, the surgery will be scheduled sometime early next week.

RESOURCES

Pedal Osteitis from Horseshoes.com

Nonseptic Pedal Osteitis: A Cause of Lameness and a Diagnosis? from IVIS.com

Pedal osteitis from Veterinary Notes for Horse Owners

Pedal osteitis from Adams Lameness in Horses

Non-septic pedal osteitis from Equine Podiatry

Pedal osteitis: A not so uncommon condition from the Equine Medical Service Newsletter

Pedal osteitis from Anvil Magazine