Back in the fall of 2020, Thunder began favoring his left hind leg. He would regularly limp or even hobble along on three legs, keeping his right hind leg suspended or only putting light pressure on it. We racked our minds trying to recall any specific incident that might have resulted in an injury, but as far as we could remember, there had been no sudden injury, and no specific moment when he went from being healthy on all fours to favoring his left hind leg. To complicate matters, he still would use his right hind leg pretty regularly too, just not all the time.
We sought advice from three different vets who ran various field tests to rule out common suspects. Was it a torn ligament? A hurt paw pad? Was he developing arthritis in his older age? After all, he was 11 years old and had spent most of those 11 years romping around on huge cattle ranches in the West, hiking volcanoes in Nicaragua, scaling mountains in Peru, and doing avalanche search and rescue training in Colorado. Even though he still seemed spritely, maybe his years and many miles were catching up to him.
One test all three veterinarians performed was a stability test on the knee joint to inspect the integrity of the various ligaments. A relatively common injury in some dogs is a torn Cranial Cruciate Ligament (CCL), or the ACL in humans (Kreuzband in German, I later learned). Between the three vets we spoke to, all were hesitant to make a prognosis, and the knee did still show signs of stability, indicating that at least some of the CCL was in tact. One of the vets chalked it up to arthritis, especially when we explained that Thunder has been a working dog most of his life.
Still, there were some things that didn’t add up. His x-ray was rather inconclusive. He seemed to have an acute pain rather than a general pain that would worsen throughout the day with use (as you might see with arthritis).
*To be clear, I am not a veterinarian and nothing in this article is medical advice, just a bit about the process we went through and some things I learned along the way. The hope is this might help you if you find yourself in a similar situation with your pup. At least you can arm yourself with a basic understanding of some of the things to keep in mind or talk to your vet about.
The vets recommended we switch to a Senior Dog Food diet and use Rimadyl, an NSAID, to manage pain and inflammation, which we did. A few weeks passed without any improvement so we scheduled an MRI. A night or two before the MRI, my wife was taking the pooch for a stroll. He was on leash and it was just a normal walk, nothing strenuous. Suddenly, Thunder yelped out in agony and began hobbling along on three legs, completely suspending his right hind leg, he was whining and obviously in serious pain. It is rare that Thunder shows that kind of pain, and the cry itself was enough to shake my wife. They made it back to the house and we called the vet to reschedule for the following morning. The next morning at the vet, the same knee-joint stability test yielded a different and more obvious result. If the CCL hadn’t been torn fully before, it was now. This seemed to match Thunder’s behavior too—a partial tear bothering him from time to time the few weeks prior, until the night it fully tore and he showed definite signs of acute pain.
The veterinary surgeon came in to repeat the test and confirmed that it was indeed a full rupture of the CCL—we didn’t even have to do the MRI. They scheduled Thunder for surgery right away.
Treatments of Torn CCL in Dogs:
Treatments will vary depending on a few factors like size and breed of the dog, extent of damage, cost, age, overall health, and lifestyle of the dog. In smaller dogs, it can be possible to recover from a partial rupture with just rest, ice, and minimal use, however, you risk developing other conditions like bone spurs, osteoarthritis, or joint issues. In our case, the vet was certain Thunder had a full rupture, and weighing in at around 25 kg, he was not considered a small dog. Surgery would be the only way to ensure he could regain function of his leg. Here in the veterinary hospital in Switzerland, they explained there are three general approaches to a torn CCL surgery in dogs. While I’m sure there are many other techniques, these are the three they mentioned to us and they are common for this kind of injury. The three are: Lateral Fabellar Suture Technique (LFS), Tibial Plateau Leveling Osteotomy (TPLO), and Tibial Tuberosity Advancement (TTA).
Lateral Fabellar Suture (LFS):
The first and least intrusive is the Lateral Fabellar Suture technique. The basic idea is to replace the torn Cranial Cruciate Ligament with a synthetic ligament/band that has similar characteristics and flexibility as the natural ligament and mimics its function. The doctors explained to us that this technique is only recommended for smaller breeds of dogs and advised against this technique for Thunder due to his size and active lifestyle.
Tibial Plateau Leveling Osteotomy (TPLO):
Another option is the TPLO which involves circumnavigating the function of the CCL (ACL) entirely by implanting a mechanism which allows the knee to function without the need for the CCL. They do this by using a piece of the dog’s own tibia and supporting it with a plate and screws. The general idea is to change the angle of the top of the shin bone (the tibial plateau) by cutting off a piece of the tibia, rotating it, and securing it with plate and screws giving the joint the same functionality it had before but bypassing the need for the ligaments. Again, I’m not a veterinarian, so I won’t pretend to understand the nuances of how this functions medically nor structurally, but it is a common surgery for this type of injury so I am sure your vet can offer more insight.
Tibial Tuberosity Advancement (TTA):
The third solution they mentioned to us, and the one they suggested we go with, is the TTA. Similar to the TPLO, the goal is to change the mechanics of the stifle (knee) joint using both the dog’s own bone structure and additional plates and screws, bypassing the need for a CCL and ensuring the ligaments are no longer necessary for stabilizing the joint. The surgeon will cut along the front part of the tibia bone, the tibial tuberosity. This off-cut bone is then advanced forward using a specialized bone spacer to separate the tibia from the cut fragment of the tibial tuberosity. In order to stabilize the new positioning of the bone, a stainless steel plate is put in place. The mechanics of this surgery rely on the function of the patellar tendon, and its attachment to the now separated tibial tuberosity. Again, I can’t explain the nuances of this surgical technique, but the result is that the CCL is no longer needed to support the structure of the joint.
I believe the surgery Thunder had was the TTA or at least a close variation of it. I am not 100 percent sure because of the different translations from Swiss German to High German to English. The different languages use different acronyms and my tenuous grasp on German means there might have been some discrepancy between what I understood and what they actually said (my wife speaks all the Germans though, so don’t worry, overall we did know what was going on).
Thunder was pretty out of it still when we went to pick him up a day or two later. His leg was shaved and looked like a raw chicken wing, and the incision down the inside of his leg along his knee was probably 15 cm long. He had to wear the cone of shame for a while. It was a very slow healing process at first. We lived on the third floor of our building so I had to walk him up and down the stairs each time and I swear he put on weight just to spite me.
Within a few days, though, he was able to begin touching his paw down and putting a bit of pressure on it here and there. The doctors said the knee was structurally sound, we would just have to limit his level of discomfort. In a few weeks, Thunder had begun to integrate his chicken wing leg into his walk every third step or so, but it was notably still quite tender. Intermittent vet check-ups and x-rays showed he was healing properly and everything seemed to be ok. After about 6 weeks, and noticeable muscle atrophy, we integrated some gentle physical therapy into Thunder’s routine to help regain muscle structure and stability and keep the joint mobile. Our physiotherapist also recommended some sessions on an aqua-treading device: a giant treadmill with the ability to fill with some water through which the dog can walk for a low-impact, resistance based rehabilitative exercise. Under her supervision and guidance, we also used a lightly weighted backpack to help Thunder regain his coordination, balance, and core-strength. You can read more about the various uses of backpacks for dogs here.
After 8 weeks or so we had the clear to begin taking 20-30 minute walks twice a day, but still no running, romping, and playing. Thunder was pretty stir crazy, being the active dog that he is, and it was heartbreaking to not be able to convey to him that it was in his best interest to remain cooped up a little longer.
Overall, his convalescence seemed to follow right along with the doctor’s predictions. Thankfully, he showed the important signs of healing at each check-up interval. His fur had begun to grow back, and where his leg muscles had atrophied, he was slowly regaining balance and stability. Still, his leg had been mostly sedentary for a few months and it showed. Sometimes his leg would quiver a bit even while resting.
Within 4 months, Thunder was virtually indistinguishable from pre-injury. Now he runs and plays and spins in circles like he used to when he was a little puppy, despite him turning 12 this month! It makes me so happy to see him back to his normal shenanigans. We go on long hikes again through the Swiss Alps, and only at the end of a long day do you notice a cheeky little wobble in his back hips as he still favors his stronger leg. The surgery might have set us back a little, but you can’t put a price on Thunder’s joy and ability to play outside. He’s a mountain dog after all, and it warms my heart to know he is back playing in those mountains he loves.
*Photos from Dallas Veterinary Surgical Center, Drover's Vet Hospital, and Thunder's own x-ray image from Tierklinik Thun, Switzerland