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Updated again 34: Osphos for older horse with navicular changes

Gonna be a long one folks.

My golden oldie has been gimpy for about 3 weeks in his RF. Since onset of gimpyness, we tried a different pad on that RF and he blew an abscess out in his LH. Horse has improved some since the abscess blew out but has good and bad days it seems. Horse has a history of laminitis, founder (more sinking than rotation), navicular, paper thin soles and of abscesses. Metabolic panels have been ok or inconclusive to date. RF has been the “bad” foot. I gave him a low dose of Bute during the worst of lameness but discontinued last Thursday so vet and farrier could see.

Vet was out today. Graded 3 lame in RF. Hoof testers on RF showed horse was sore in heels as opposed to the toe, particularly the medial heel. Horse did not react to hood testers on LF. X rays (both fronts) showed no changes in sinking or rotation but tip of P3 is feathered / turned up (I believe this is Pedal Ostitis?) more than last x rays in Oct. Sole depth has greatly improved compared to Oct. Vet feels that when considering results from hoof testers and the history that the changes in P3 are more incidental findings as opposed to cause of current lameness and that the changes are somewhat expected due to pressure on P3 last fall during laminitis attack / founder on scary thin soles. X rays also show that the navicular changes have “progressed” compared to last October (both fronts). Vet feels this is more consistent with current lameness however since horse is presenting as only lame in RF an abscess could be brewing. Nobody (vet, farrier or myself) wants to try and dig this potential abscess out. Will try soaking or packing for a few days and see if anything happens. We are starting daily Previcoxx.

At any rate, the progression of navicular changes is concerning and vet recommended Osphos. I’ve never used this product on a horse before. A quick COTH search shows there’s a concern about kidney function and colic. Upcoming, horses will be due for spring dentals, vaxx and we are going to run the “simulation” test for metabolic / PPID on the old guy. Plus the Osphos injection potentially. How would you all recommend organizing this work? Seems like a blood test to check kidney function prior to the Osphos would be needed. Maybe do the BW, the vax and the metabolic test at one appointment and then the following week do the dentals and the Osphos? I think one thread in my search indicated that slight sedation might ward off potential colic side effect from Osphos?

Horse is “grade TB”, per previous owner (not the breeder or track connections) horse is 18, my vet feels teeth say horse is older (22). If age matters.

We’ll be changing his shoeing up at his next farrier appt in two weeks.

I expect I’ll have today’s x rays by tomorrow via email.

I’d welcome any stories or thoughts about Osphos. Or heck even commiserate with me on horses with lots of problems!

Osphos was a miracle drug for my gelding. It was suggested as a last ditch effort to make him pasture sound with end stage DJD. Our other option was euthanasia, so the potential liver issues did not concern me as much as they might concern others. I did ask my vet about proactively treating with banamine, and she nixed it due to the stress Osphos would already be putting the kidneys and liver under.
He did not react to the Osphos like some horses have been reported doing. He us a very stoic horse fwiw, and I doubt we gave him his first Osphos injection since he went through the yearling sales before it was illegal.
4 years later he is still sound and in full work. He has not had it repeated, but I would not hesitate to give it again.


What a super outcome for your horse!

My horse has been retired for about 5 years. 3 before he came to me. Just hoping to keep him around longer :heart:

Another resounding YES for Osphos in older horses with navicular changes. Horse in this story is a lesson horse of unknown age (mid-upper 20s was best guess a few years ago) who has a pretty clubbed LF with a BAD x-ray. He’s had coffin joint injections and navicular bursa injections and the one thing that made a HUGE difference was the Osphos. Makes him feel about 10 years younger at least. He’s on a schedule about every 10-12 months. We have not seen any negative results in the rest of his health.


Oh wow! He’s still packing in lessons? Thanks for sharing

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Yes, he is the best lesson horse in the world. Everyone wants to draw him at IEA shows because he’s such a rock star. He’s old and priceless so he doesn’t jump more than 2’ ever in order to preserve him as much as possible. But he was still showing on our local circuit last year and will probably be showing cross rails this year as well.


Osphos can be great. But you are right about the risks. I had a younger horse with pedal osteitis in one foot, and the vets recommended doing regional limb perfusion of Tildren instead. It’s a related drug given IV. The goal is lower dose, more targeted approach, and hope for fewer side effects. We did a couple of treatments. It did seem to help. He was sound on that foot going forward even after developing some soft tissue issues in it near the navicular area some years later (was lame on the other foot and I did bilateral MRI).

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Oh that’s amazing!

I love me some old horses. Such characters!

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Good to hear you saw good results with a related treatment. My vet felt like Osphos was her first choice for my horse. He shows progressing navicular changes in both fronts. I haven’t done x rays on his hind feet yet so goodness knows what he has going on back there. I don’t think I have anyways. Might need to check myself lol.

I have some spotty history on the horse, but the gist of it is he’s had front feet lameness issues for almost a decade. I’m in regular contact with his family that had him before the lady I got him from (he was the daughter’s junior horse). I’m positive they didn’t do any sort of injections on him but I can double check. I’m also considering reaching out to the lady I got him from and seeing if she’d ever had Osphos done. I dunno if that’s pertinent or not? But might be worth asking? I’d have to go through the trainer that connected us or the family that had him before. It might be useful information to confirm?

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My gelding did really well on Osphos. He had several shots when he was 27-28 and I retired from riding. He had a lump on his left knee when I bought him at age 7 in 2001. It was outside the joint and never bothered him or affected his way of going. We became good friends with our vet because I ran Barn Day. His annual exaim included flexing that joint, then shots. The flexion began declining and there were signs of arthritis when he reached the early 20s. He was still perfect when I rode, through 3/31/2020. The BO locked up all the horses on pasture board, mostly school horses, for the month of April 2020 and didn’t let any owners on the property. She knew she didn’t have to close the barn but she lied, claiming the governor ordered it for COVID.

When we were reunited on 5/1/2020 he wasn’t interested in working at all after standing around for a month. As gently as I tried to get him going, he started having episodes of lameness in mid-July, but recovered and was sound. In October it changed. He was chronically lame and losing weight because he wasn’t getting enough hay. I moved to another barn (11/2020, after 19 years) and went to a lameness vet in 1/2021. That is when he got his first shot of Osphos, plus a joint injection of steriods and antibiotics. He definitely was much more comfortable. His right hind was stocked up about halfway up the canon bone after a small cut on the back of the leg a few years earlier. No problems with that one, either. I’m not sure anyone else noticed. I looked at him one day a month or so after the Osphos and that hind leg was normal. Inflammation was gone from the coronary band past the pastern and fetlock and beyond. It never returned. We did a very short Century Ride on 6/21/2021.

He got a couple of more shots of Osphos, probably about 4-6 months when the knee showed a little stiffness. Through all of this he remained a bundle of energy and was happy to be pampered and spoiled, but the knee was definitley going downhill. He got a shot of Osphos in late May 2022. It was amazing how much stronger he felt. I had to work hard to keep up with him at the walk. As bad as the lameness was getting he didn’t show signs of pain. He could put 100% weight on it when standing, but usually favored it.

The vet said it was time in mid-July. I thought she was jumping the gun but set 7/20/2022 as the day, I was able to watch him walking from the side and behind and it was clear: not enough flexion. He was still very strong overall, but a couple of days later wouldn’t walk away from the barn to hand graze. Everyone figured he would make it at least until the cold weather. I always knew his knee would take him. His knee was showing problems controlling the hoof. There were scuffs on the right that looked like he stumbled. The decline was over 3-4 days which still shocks me.

The Osphos definitely helped keep him comfortable and active. Getting rid of the inflammation in the right hind was a nice surprise. I didn’t worry about long-term risks at his age. He didn’t show any immediate side effects when he got the injection. I guess I could have tried to keep him going longer but I didn’t want to force him to be a gimpy old man stuck in his stall. He had a unique relationship with human beings. He was a perfect therapy horse. People (including the UPS driver) looked at him for the1st time and fell in love instantly. He was 28 and widely recognized by kids and adults in a chunk of southern Maine. A few dozen friends were with us when he went over the bridge. “He touched so many lives in so many different ways.”


Thanks for sharing! Hopefully my guy will see good results too

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I just had the vet out Thursday for a lameness evaluation & osphos shot for my 23 yr old ottb. I wanted the evaluation so I know if it does anything for him but he is not lame. We’re using it for hock arthritis. Toes are long so we have to go back to a 3 week trim cycle. No bute, banamine or pain meds for 2/3 days prior to injection because it overwhelms the kidneys. Do a chemistry panel & a cbc with spring vetting & the injection at a later visit.

Since I’m in the middle of nowhere I wanted the vet out in case he had a reaction. You can only use buscospan if they colic. I ran bloodwork in October & everything was fine. He only had mild irritation in the neck where the injection was done. He was fine by the time she finished pulling coggins & adjusted the 5 yr old. I didn’t have to call them to send the vet back. From what I found online researching it’s anywhere from 2 to 6 weeks to see improvement. We’re going to do osphos as needed every 6/12 months if it works for him. If it doesn’t I’ll probably try prostride in the hocks. I have the vet back in 4 weeks for spring shots so they should be able to see if it’s done anything. I haven’t gone down the rabbit hole of x-rays yet since he’s cure sound.

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I’ve used Osphos in my horses on and off since he’s been a senior. No ill effects and it has helped any front end issues he has had. It’s a good tool to have available.

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Thankfully the vet clinic is basically around the corner from our farm! I don’t think my horse has had a regular blood panel since last Spring so we’ll definitely do a fresh one first.

Hope it helps your boy. Getting those toes back is a thing! We are on a 4 week shoeing cycle but my farrier often stops in at the two week mark and rasps toes a bit since this horse has “toe issues”.

I’m working on getting my horse’s medical records from past two owners released / forwarded to my vet. The previous owners are being super helpful. Everyone wants the best outcome for horse.

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Good to hear!

Sounds like a good plan. My vet won’t give it without having results back from the bloodwork. I used Tildren (essentially the same) back when it was very new around here and getting shipped in from Europe by the dose. We would give it first thing in the morning so someone was around to watch the horse for the day. Back then we were pre-treating with banamine, but they quickly stopped that and started leaving a dose of Buscopan for the owner to administer in case of cramping. That said, I never had to give it. Ours all tolerated it well (both as systemic and as regional limb perfusion).

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That’s a good idea about scheduling for AM. Thank you for sharing

I’ve got a 17-year-old horse with navicular and I’m needing to come up with a better management plan for him this year. I did try Osphos two years ago and I did not notice any difference, so unfortunately I do not think it helped for him at all. I don’t know that I would try it again since he didn’t seem to respond the first time.

He did not have any side effects from it.

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Bummer it didn’t help your horse but glad to know he didn’t have any adverse reactions.

I’m in quite a pickle with my guy too. I guess a common management tool is lifting the heels via shoes or wedge pads but for my guy that’s really not ideal bc that’s gonna put pressure on his toes that are also damaged. Horses! Always something.

When I bought my horse in 2001 he had long toes and a pair of keg shoes tacked on. The farrier started him in Natural Balance shoes which helped get the breakover back where it belonged. The vet x-rayed his feet and his pastern angles were not good. We put him in a 2-degree wedge pad, the style with the v-shaped section under the frog. He couldn’t keep aluminum shoes on longer than 10-14 days. Switched to NB light when they came out. Farrier tried him in Avanti shoes and they were incredible. They don’t move the breakover but are contoured so it takes a lot of stress off soft tissues.

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