Intra-Articular (Hock) Injections

Four of them to be precise, and all of them in the hocks. I've had Izzy's hocks injected twice (here and here), and even though I geek out on Dr. Tolley's "lessons," I learned all kinds of new stuff for this round. Maybe I just asked better questions this time. After Speedy's bodywork on Monday, the chiropractor felt like Speedy could use some pharmaceutical support, and my vet agreed.

A little "vet is coming" makes for a great photo opportunity.

When we pulled into Bakersfield Large Animal Hospital thirty minutes ahead of schedule, Dr. Tolley was already out there ready to greet us. While his "guys" finished with another horse, Dr. Tolley and I walked over to the scale. Before Speedy got on, Dr. Tolley stated that no matter what the scale read, Speedy's condition looked perfect to him. I agreed. Speedy clocked in at a reasonable 966 pounds. He's weighed as much as 1,000, but he looks good at this weight.

Given that Speedy has been a patient for thirteen years, both Dr. Tolley and I were well aware that hock injections might not be so easy. It took four of us, but we got the job done without much of a fuss, thankfully. Rudy did the prep work, Kathryn helped load syringes and worked the twitch (after Speedy had been tranquilized/sedated AND given a local anesthetic), Dr. Tolley did the injections, and I let Speedy know that it was all going to be okay. It's not like I am some kind of horse whisperer, but there have been many times that I've had to assist before Speedy would let something be done to him - sutures last year comes to mind.

Rudy prepping the injection site.

When you think about "injecting a hock," what comes to mind is that big bony knob that sticks out. At least that's what I thought. It turns out that while that is a high motion joint, that's not the part of the hock that needs any help. Instead, it's the two bones stacked below it that form the intertarsal joint which is actually a low motion joint. When a hock fuses, it's these two bones that connect. 

This is NOT Speedy's x-ray, but it was one from Dr. Tolley's files.

For whatever reason, and Dr. Tolley didn't know the why, the tibiotarsal joint, that big knobby joint above my red circles that allows the hock to actually articulate, rarely needs any help. It's the pancake-like bones below it that form the joint that gets painful. In the red circles above, you can see what should be spaces. The blue line shows where and how far in the needle goes. Dr. Tolley drew the line to illustrate what he had done. Like I said; his lectures are awesome. In a horse with arthritis, the gaps between the joints become filled with extra bone. This reduces the space between the bones which has the effect of restricting the amount of fluid that can actually fill in the empty spaces. And of course, once the hock "fuses," there's nowhere for fluid to go which is why you can no longer inject those joints.  

A view of the second injection site, and again NOT Speedy.

The green line in the photo above illustrates where and how deep the needle penetrates on the inside of the joint (proximal?). Again, if the gap has been reduced by arthritis, the fluid can't flow where there are no open spaces. Once Dr. Tolley had finished with all four injections - inside and outside of each leg, he pointed out something quite positive. When he depressed the plunger of the needle, he was met with virtually no resistance. This means that Speedy's joints are well open with plenty of space for the liquid to flow. Of course that would suggest that he probably has little to no arthritis in those joints. Without x-rays, we can't know exactly what his joints look like, but they're more than likely pretty good, especially for a sixteen year old horse.

You might be asking why we didn't do x-rays. Well the simple answer is that it wouldn't have changed anything. X-rays wouldn't have helped Dr. Tolley do the injections. All they would have done is shown the current state of his hocks. Since Speedy hasn't ever had hind end lameness issues, we really didn't need a picture. He either has arthritic changes or he doesn't. All x-rays would have done at this point would be to serve as a reference point for the future. 

So if Speedy doesn't have arthritis, why inject the hocks at all? Dr. Tolley is not a fan or prophylactically injecting joints. The injections are steroids after all, and high levels of steroids can cause all sorts of problems. Both Dr. Tolley and my chiropractor felt that with Speedy's current workload, his joints are starting to complain a little bit. Maybe more than a little. Injecting the joints served to reduce the inflammation and pain. Dr. Tolley was quick to point out that every joint responds differently, and that there is no "one" perfect joint drug. If you ask ten different vets which drug they think should be used on hock joints, he said that you'd likely get ten different answers.

Dr. Tolley's choice for hocks.

Over the past year or so, Dr. Tolley has made the decision to switch to a combination of betamethasone and Adequan. He feels that drug, the betamethasone, is doing a better job of reducing inflammation and pain in this particular joint. In the past, he tended to use Depo-medrol and Adequan (or sometimes hyaluronic acid). That's what he's given Izzy the two times he needed hock injections. I am not a vet, so I am not going to challenge him on which drug is more effective, but I did ask why, and he was happy to explain his reasoning. Works for me.

The day after his bodywork, Speedy's hamstrings already felt much better. When I ran my thumbs down his backside, he got slightly irritated, but the muscles didn't twitch and spasm as they had the day before. Dr. Tolley recommended three days of rest which means I can ride Speedy lightly over the weekend. By Monday, he has the all-clear to return to his regular workload. Of course, I am taking Izzy to a clinic that day, so Speedy will get an extra day of rest. I don't think he'll complain.

He had his tongue out for every photo!

Hopefully, this isn't an annual thing, but if it is, it is. Izzy needed it done twice, but now that he's so much more "broke," there's a lot less jackassery, and he feels great. I am really hoping that between the bodywork and hock injections, Speedy's half passes might show some sudden improvement. Either that or we just keep working on it.

Have a great weekend!