CRUCIATE LIGAMENT INJURIES IN THE DOG

The most common musculoskeletal injury that we see in the dog is a ruptured cranial cruciate ligament (CCL) in the knee joint.  In humans, this is called an ACL injury.  It is seen frequently in larger breeds, especially those that are athletic in nature.  Most dog caretakers report that the injury occurred during some physical activity such as chasing a ball or running up the stairs.

The cruciate ligaments are a paired set of ligaments in the knee joint.  There is both an cranial (anterior in humans) and caudal (posterior in humans) cruciate ligament that cross each other as both have attachments in the opposite place that help stabilize the knee.  Cruciate in latin means “cross.”  The cranial cruciate ligament is mostly damaged because dogs walk forward, which puts most of the thrust on the cranial ligament.  On occasion, a dog will partially tear the anterior cruciate ligament, but most of the time it is a full rupture of the ligament.

Since the cruciate ligaments function to stabilize the knee joint (front to back stabilization), when the CCL is ruptured, the log gets immediate instability in the knee and the excess movement causes a great amount of pain.  Most dogs will carry the affected leg instead of bearing any weight. 

The standard treatment for ruptured CCLs is surgical repair.  Using surgery, the knee can be re-stabilized in order to reduce the pain and reduce the possibility of degenerative changes in the knee joint (arthritis).  Other complications can occur when the CCL is ruptured.  There may be a tear in the meniscal cartilage which can be fixed during surgery as well.  Very infrequently, the causal cruciate ligament is damaged.

When your dog has injured its rear leg and the vet has determined that the pain is coming from the knee joint, he/she will likely attempt to manipulate the injured knee, looking for excess anterior to posterior movement.  This is called a “drawer sign.”  Much like the drawers on you chest in your bedroom, the bottom part of the leg (tibia) moves forward like a drawer sliding out.  A dog with a drawer sign, most always has a ruptured CCL.  Surgery will likely be the veterinarians recommendations.

Now that you have the textbook version, which is what all of us were taught in vet school, let’s look at thing from a holistic perspective and see if we can dig a little deeper.  I will also point out some of the flaws that I am now seeing with the current recommendations regarding surgery.

Because most dogs will have an acute or sudden onset of pain, it appears that the injury just happened.  This is what we used to think when it came to CCL ruptures.  But, that is not quite what happens.  It appears that almost all of the time, the cruciate ligament has been unhealthy for some time.  The cruciate ligament is made of many filament-like bands, much like a multi-filament cord.  It appears that the filaments of the ligament start to tear and it “frays” the ligament.  Eventually, some physical activity usually tears the remaining viable filaments and the ligament is no longer functional.  Some dogs will just tear some of the remaining filaments and this is what we refer to as a partial tear.  The point is that it is not an acute problem.  It is a chronic problem that appears to be an acute problem due to an acute injury.  This is evidenced by the presence of arthritic changes within the knee at the time of surgical repair.

How does the ligament begin to fray?  Some veterinarians say that due to an abnormal sloping of the top of the tibia bone causes the weight of the dog’s hindquarter to shift forward, putting extra weight and stress on the CCL.  There are other considerations.

From a Traditional Chinese Veterinary medicine perspective, the liver is responsible for the ligaments, tendons and sinews, so most of the problems associated with these structures are due to liver imbalance.  Also, the liver is responsible for storing blood and when it is out of balance, we often see blood deficiencies.  Blood is pure yin (moisture) and when deficient, the ligaments will start to dry out and guess what?  They start to fray.  This is why I include fortifying blood and balancing liver when I work with dogs that have torn CCLs.  Since most dogs that tear a CCL will tear the CCL in the other knee, I want to try to prevent this from happening.

When I used to practice conventional veterinary medicine, I did a lot of surgical repairs for dogs with CCL ruptures.  I worked at a Labrador Specialty Practice for several years and we worked on field trial Labradors from all over the country.  Many of them had ruptured CCLs.  We did between 8-10 CCL surgeries a week, more than the orthopedic surgeon was doing.  So, we became quite proficient.

The reason that I mention this is because I want to tell you, of the hundreds of dogs that I did CCL surgery, more than 95% of them healed well without complications.  The surgical technique we used at that time is called a modified Flow technique.  We would do another procedure as well, called a tibial head translocation to make sure the knee was stable as these dogs worked in the field for 6-8 hours a day for their training.  Both of these surgical protocols were extra capsular, meaning that the stabilization was done outside the joint capsule. It was a very good protocol and these dogs benefitted greatly from this.

One day, my colleague’s dog was training and he fell off a bridge and damaged a previously repaired knee.  He was not sure what he should do surgically but he had heard about a veterinary surgeon on Oregon who was studying new ways of repairing CCL injuries.  His name was Dr. Barkley Slocum.

My colleague contacted Dr. Slocum and he was invited to bring his Labrador out to Oregon and have surgery done there.  He loaded his Labrador on the airline and went off to Oregon.  When my colleague arrived and met Dr. Slocum he was told that he must sign a waiver, stating that he would not discuss with anyone the information about the surgery that was to be done on his dog.  The document was signed and the surgery was done.  The dog recovered without complications.

The surgical protocol that Dr. Slocum had developed is called a TPLO (tibial plateau leveling osteotomy).  The reason behind the secrecy was that Dr. Slocum had a patent done for this procedure and no one was allowed to do the procedure without his consent and the only way that he would give you the consent was if you took his surgical course and bought his equipment.  Wow.  This was the first time anyone had ever done a patent on a surgical protocol.  Unfortunately, shortly after this was set up, Dr. Slocum died.  I am not certain how, but his protocol was released to other veterinarians.

Immediately, the veterinary orthopedic surgeons began doing this surgical repair on all dogs with ruptured CCLs.  It was like a bunch of kids playing with the electric train they got at Christmas.  Obviously, since it was a new protocol, no long-term studies had been done.

Several years later a group of veterinarians, specializing in sports medicine in dogs, led by Dr. Bartles at the U. of Tennessee veterinary hospital did research on CCL injuries, surgical options and how they compared with efficacy for creating a near normal knee joint.  Their finding were a bit shocking.  Ultimately, it said that the knee joint would look and perform the same in a couple of years, no matter what the surgical procedure was used.  Ouch.

Now, that $3000 TPLO wasn’t looking that great.  So, the veterinary orthopedic association got together to discuss these findings and decided that they would just recommend this procedure on big, heavy dogs over 100 pounds, since they would likely break down the extra capsular surgical protocols previously used.  Not so with my experience.

The other thing that was found with Dr. Bartles research shook our foundation for surgical intervention.  Up until that time, we told clients with dogs with CCL ruptures that we had two goals.  One was to stabilize the unstable knee and the other was to prevent arthritis formation in the joint.  Dr. Bartles research stated that all dogs with ruptured CCLs, no matter what surgical protocol was used, will develop arthritis.  Ouch, there goes one of our reasons for surgery.  But, we still had the ability to stabilize the joint.  Guess what, if you give the knee some time, it appears that it will stabilize itself.  Ouch again.  There goes our two primary reasons for doing surgery on the damaged knee.

I am not saying that dogs should not have surgical repair done for their ruptured CCLs, but I am saying that we should strongly look at all the options and considerations before making that choice.  Once again, lets look at what is currently the perspective with these surgical repairs.

It appears that most, if not all, veterinary colleges are only doing TPLO (and TTAs, which is a modification of the TPLO) on dogs with ruptured CCLs.  They are no longer giving the option of having an extra capsular procedure done, no matter what the size dog.  This means that anyone scheduling a CCL repair will only have those two options.  This also means that the vet students are being taught that these are the only two options for surgical repair and not even getting the opportunity to learn other options.  How important is this?

Let’s compare the protocols again.  Remember, I told you that when surgeons started doing this protocol, no long-term effects had been noted.  It appears that one of the down sides of this procedure is if something goes wrong then really bad things might happen.  Many dogs that have complications with this protocol end up having to have an amputation done.  When doing the extra capsular protocols for many years, the few post-operative complications that were seen required some minor correction, perhaps removing a band.  Certainly, not leading to an amputation.  Imagine having a $3000 surgical repair done for a damaged CCL that may have healed on its own only to end up having to amputate the affected leg.  I can’t.

Let’s get back to the young vet student who has been led to believe that these surgical repairs are the only options.  Here is a real life story.

Once upon a time, an elderly gentleman noticed that his 10 year old Labrador was limping on a hind leg.  Being a caring pet caretaker, he took his old dog to the vet.  After a thorough examination and xrays, the young lady vet told the older gentleman that his dog had a ruptured CCL.  She also told him that his dog would require a special surgical procedure that she was unable to do but she would refer him to an orthopedic surgeon who would repair the knee.  He was also told that the surgery would be about $3000.  He told her that he was retired and lived on a fixed income and could not afford to have the surgery done for his dog.  She then told him that his dog would suffer without the surgery.  The old gentleman loved his dog and could not be selfish enough to allow his dog to suffer.  The old dog was euthanized.

Now, if this doesn’t make your blood boil, it should.  The fact is, if this old gentleman took his dog home and did absolutely nothing, in six months the dog would be using the leg enough to function.  There might be some pain (which could be addressed) and some arthritic development (which could be addressed) but there was no reason to euthanize this dog.

   These are my recommendations for dogs with CCL ruptures:

  1. If you want surgery and your dog weighs less than 80 pounds, find an experienced veterinarian who has done extra capsular procedures to do the work. If your dog weighs over 80 pounds, discuss the protocol with the surgeon and make sure that you are aware of potential complications before the surgery and not after the fact, when it is too late.  Remember, no surgery is guaranteed to be successful.  I know, I work on them every week in my office.
  2. If you choose not to do the surgery. Find ways to reduce the pain and inflammation and slow down arthritic development.  Consult a holistic vet to help you.
  3. Do not even consider doing surgery on a dog that is 10 years or older.
  4. If you have a big dog that has the potential to rupture his CCL, find ways to prevent it from happening. It can be done.  It starts with feeding the correct diet.  The old saying, “Food trumps genetics” is absolutely correct.  Look outside the box for answers that you might not get from your conventional veterinarian.