I truly hope that you will never have to find out what the acronym ACL/CCL means. But if your dog develops sudden lameness in a hind leg, and particularly if he is a large breed, you might hear your vet say these letters…
|Image from Dog Health Handbook|
ACL is short for anterior cruciate ligament. Sometimes it’s also referred to as CCL, which stands for cranial cruciate ligament. Same thing.
So what is it? The ACL is one of two little ligaments that cross each other inside the knee and hold the large bones that form the joint in place.
Ruptured Anterior (Cranial) Cruciate Ligament
If the ACL ruptures, the tibia/shinbone can slide forward and away from its normal orientation with the femur/thighbone.. That causes pain, joint instability and in the long term, it leads to arthritis. If your dog has injured his ACL, he will be hesitant to bear weight on the affected leg or he may not put that foot down at all.
The tear can be full or partial. A complete rupture causes the most joint instability but even a partial tear means that the ligament cannot function properly.
ACL ruptures can happen as an acute or sudden injury. This is actually the better of the two scenarios. It means that some dramatic trauma to the joint has caused an otherwise normal ACL to tear. The upside is that only one leg is likely to be affected.
More often though, the rupture is a result of a chronic weakening of the ligaments, where they become more and more frail until they finally let go. If this is the case, sadly, sooner or later the other ligament will often fail as well. There is a number of reasons why this happens. Among others, there seems to be a connection between hypothyroidism and ACL failure.
So now that it has happened, what do you do? You have to do something. The thing about ligaments is that they don’t heal very well. It is possible for a knee with a mild, partially ruptured ACL to heal with rest and physical therapy, but more severe injuries are unlikely to repair themselves on their own. The longer the knee is unstable, the more severe is arthritis that will develop, and now you have two problems instead of just one. So it is best to deal with is as soon as possible.
First, get a good diagnosis, ideally from an orthopedic surgeon, to make sure you know what you’re dealing with. Then you have choices to make among several different treatment options.
Some people take a minimalists approach. The knee CAN stabilize on its own with very controlled exercise only, by the means of scar tissue forming around the joint and stabilizing it that way. I have seen posts by people who have done this successfully. But seriously, how well do you think you can control every movement your dog makes?
When Jasmine injured her ACL, we did a lot of research, looked into all the options and considered this one as well. But we didn’t feel convinced that the odds of this being successful were that great.
Your decision should depend on your dog’s age, size, overall health, and activity level.
If your dog is quite old or cannot undergo surgery, then your best choice might be a knee brace. There is a number of products out there and I encourage you to check them all out. There are unilateral and bilateral brace products available. Look at all of them before picking the one that will work best for your dog.
During our research, the product I liked the best and would have gone with if we didn’t decide on surgery is OrthoPets brace http://www.orthopets.com/ACLStifleDevice.htm. The guy who runs the place used to make braces for athletes and has it really figured out. In my opinion, this is a superior product.
For more information about non-surgical options please read ACL Injuries in Dogs: Non-Surgical Alternatives?
If your dog is still young and is otherwise healthy, surgery might be the best option. We’ve been through this with Jasmine twice. It is heartbreaking, but I do believe it’s the best thing to do.
Which surgery to chose is a different question altogether. In the past, surgeons often attempted to reconstruct the ligament. But that didn’t seem very successful. Just as the once damaged ligament cannot heal, it seems it cannot really be replaced either. So that leaves us with joint stabilization surgeries.
Presently the most popular and most commonly used modern surgeries are TPLO and TTA, the TPLO being more common. Both TPLO and TTA stabilize the stifle by altering the joint anatomy.
Which one is better – the answer will depend mainly on who you ask. The best way to make the optimal decision would be to talk to a surgeon who is certified and has experience with both and get a recommendation best suited for your dog.
Most often though you’ll run into a surgeon who does and believes in one of them. In any case, make sure that whichever surgery you pick, you have a surgeon who is comfortable doing it and has the experience and skill needed to do it well.
It is easier to understand what this surgery does by translating it into English. The two bones meeting in the knee joint are the tibia (i.e., shinbone) and femur (i.e., thighbone). The tibial plateau is the top, relatively level surface of the shinbone, on which the thighbone sits within the knee joint. I say relatively level because there is actually a slant to it. Without the support of an intact cruciate ligament, there is nothing to prevent the thighbone from sliding out of place.
In a TPLO, the top portion of the shinbone is cut and rotated in order to change the slant of the tibial plateau which stabilizes the joint. The bone is secured in its new place by metal plates.
Because this surgery is done to a weight-bearing part of the bone, it often takes longer for the dog to bear weight on the leg. While I find it quite invasive, I do believe that it provides good stability when it’s done well. I do feel that there is quite a bit of room for error, so make sure you pick a good, experienced surgeon.
Another way to increase the stability of the stifle joint is to modify the relationship between the slope of the top of the shinbone and the patellar tendon. The patellar tendon attaches the kneecap to the front part of the shinbone.
In a TTA, a wedge is cut in the top of the shinbone and the piece of bone pushed forward. This also pulls the patellar tendon forward, which helps prevent abnormal movement within the knee.
The bone is secured in place by titanium implants and the open area is filled with a bone graft.
Because the surgery is done to a non-weight-bearing part of the bone, your dog will start bearing weight sooner. In comparison to a TPLO, a TTA does look somewhat less invasive to me, but, they both involve chopping and repositioning of bone. If done right and with nothing going wrong during the post-op period, both surgeries seem to be quite successful though. Their objective is to stabilize the knee in such a way so that the cruciate ligament isn’t needed anymore. I recommend you look them up in detail to have a good idea of how each of them is done and how they work.
This is a new technique that originated in New Zealand and it is presently available in New Zealand, Australia, and England. It combines elements of both the TPLO and TTA and it actually looks quite cool. I describe it in more detail in my article Newest Surgery for Ruptured ACL in Dogs.
This is an older type of surgery, largely abandoned particularly for larger breeds. However, this is the one we opted for. One of the reasons was that it is the least invasive. It involves drilling small holes in the bones and stabilizing the joint by use of a surgical cord. The great vet we found has done quite a number of them on both small and large dogs with great success. There seems to be evidence that there is virtually no difference between TPLO and extracapsular repair 18 months post surgery.
For larger dogs, our vet uses two sutures for better stability. Whether or not this could be an option for you depends largely on three things. Whether you have a great vet who you trust and know he has the necessary expertise, your dog’s tibial plateau angle, and your ability to follow through with a strict post-op protocol, which is crucial for proper healing.
The stabilizing sutures are meant to hold the joint in place only long enough for fibrous/scar tissue to develop, and it is the scar tissue that stabilizes the knee at the end.
Jasmine had it done on both knees, three months apart and with great results.
The above links have good information on this relatively new technique. It does seem to be a good option. Our vet was a bit skeptical about this one. But it is also minimally invasive.
So you see there are choices. Each of them has its pro’s and cons. My main points here are, know your options, and do your homework. Always. One cannot make a good decision without information. Understand all your options, discuss them with your veterinarian or surgeon and then make a decision.
Don’t wait too long though, this is one of those problems that will not go away by being ignored,.delay will only cause additional problems down the line.