We received the following long – but very informative – letter from Evelyn Orenbuch, DVM, the vice president of the American Association of Rehabilitation Veterinarians. It helps further our readers’ education about their options for treating canine CCL injuries.
I was excited to read “Saying ‘No’ to Surgery” (Whole Dog Journal February 2010) about “conservative management” for ligament injuries. As a veterinarian who has practiced only physical rehabilitation for the past seven years, I am encouraged to see any article describing its benefits. Author CJ Puotinen was quite thorough in her list of treatments and supplements that can and should be included in a conservative management regime. However, I was distressed by a few points in the article.
When discussing surgical options, the author starts out by telling the story of a dog owner who was warned away from the tibial plateau leveling osteotomy (TPLO) method by Dr. Gail Smith at the University of Pennsylvania School of Veterinary Medicine. I realize that this story was simply a discussion of what the dog owner experienced, but it leaves readers believing that TPLO surgery should be avoided.
If one were to look further, one would see that the surgeons at UPenn are almost completely alone in their objections to TPLO surgery. I am pretty sure that UPenn’s veterinary college is the only one in the country (there are 28 of them) that does not teach this method. I have attended Dr. Smith’s lectures and have seen his line drawings of vectors and forces to the knee and his physics explanation of why it doesn’t work. The problem is, in an actual animal (not just the drawing), it does work and it works well. Many dogs in this country have received this surgery and have not only returned to being happy comfortable pets but also returned to full athletic competition.
In the sidebar titled “Surgical Options,” the author quotes a study done by Dr. Mike Conzemius et. al., in which the authors studied limb function after various surgical techniques for ruptured cranial cruciate ligaments with injury to the medial meniscus. Although the author’s citation is accurate, it is not complete. The study was not intended to prove that surgery was or was not an option. It appears that Ms. Puotinen used it to show why conservative management is a good idea. This could not be farther from the point of the study.
The authors of the study were quoted in the article as saying, “We did not include a group that was treated with nonsurgical management because it has been well established that large-breed dogs have poor outcome with this treatment.” The study compared normal dogs to post-op CCL dogs. It did not compare dogs who were treated with conservative management to those who experienced surgery.
If you were to put a dog treated conservatively on a force plate six months post-injury (as was done in the study) there would still not be 100 percent weight-bearing on that limb. Also, although the number of dogs who returned to “normal function” seems low, realize that all of the dogs improved; they just did not have equal weight bearing of the hind legs.
Even the authors state, “Our finding that the gait of most dogs six months after surgery was more abnormal than normal was surprising, because although we did not formally document owners’ impressions of outcome, it was our opinion that most owners thought their dogs functioned acceptably as pets. If this is true, one could conclude that our definition of a clinically important improvement was too rigorous.” In other words, the owners of most of these dogs will tell you that six months post-op, their dogs look good and play well. A force plate is an extremely sensitive tool and can pick up even the smallest of differences in weight-bearing.
Post-op physical rehabilitation was recommended to all owners in this study but was not documented or followed. I would suggest that this is probably the most important key to returning a dog to full function post-op. If a dog has three strong legs and one weak one, he will continue to overutilize the good legs. It is only when you press the issue through exercises and rehab that you can get him to be more balanced in his gait. So, because we do not know which dogs followed a post-op rehab protocol, we cannot know if that affected the study.
Finally, the study looked at these dogs six months after surgery. According to their owners, they are functional. Where would they be in another six months? I think we all expect things to heal instantly just because we put effort into it. The body can only do so much. The tissues need to repair, regrow, and find new ways of function. Even the woman quoted at the end of the article said that her own ACL tear took 10 months to heal.
Two additional points
1. Early in the article, the author mentions that the medial buttress is evidence that there is arthritis. This is incorrect. The medial buttress is a buildup of heavy fibrous tissue on the top part of the tibia. It is often believed to be the body’s response to the instability of the joint after the tear of the CCL but has been found to be present even before instability is found. It has no correlation to the amount or existence of arthritis inside the joint. I have seen many X-rays of canine stifles in which I can feel a large medial buttress but see no arthritis. All dogs who receive conservative treatment will develop this but it is not in and of itself cause for alarm.
2. Ms. Puotinen brings up the issue of bone cancer in some dogs after receiving a TPLO. Let’s try not to demonize the surgery here. Yes, there were a few cases of this. There appears to have been a batch of poorly manufactured bone plates that corroded and caused a slightly higher incidence of bone cancer in dogs who had received these plates. However, these issues have been addressed and since then there have not been any studies to definitively correlate TPLO surgery with bone cancer. Remember that the proximal tibia is not an uncommon area to get bone cancer and any time you disrupt an area, you can turn on the genes for cancer expression.
Surgery is not the only or even the best route. Conservative treatment can be the best choice for many and I commend WDJ for taking on this topic, but it is important not to condemn surgery as a treatment for CCL injuries. It is the best option for the majority of dogs and their owners; the most important thing is to find the right surgeon. Find someone who will look at your dog as a whole. What does your dog do for a living? How big or small is he? How old? How sensitive to surgical anesthetics? How severe are the signs? Is he three-legged lame or just bearing less weight on the affected leg? Many more questions need answers.
One last point. I am the vice-president for the American Association of Rehabilitation Veterinarians (AARV). Author Lisa Rodier interviewed me for your article “Canine Rehab? Go, Go, Go” (September 2009). One of the major issues discussed in that article is that we need to make sure that when we talk about physical rehabilitation in animals we do not call it physical therapy (PT). PT can be performed only by a licensed physical therapist. There are many animal rehabilitation practitioners working on our animals today and most of them are not PTs.
A veterinarian – preferably a rehab-trained veterinarian – should oversee the treatments of any animal receiving physical rehabilitation. If we call it PT, we potentially lose its importance. This may seem like only semantics but believe me, this is a big deal. Veterinarians and PTs together make an awesome team. Many rehab clinics employ PTs and can’t imagine working without them. But, ultimately it is a part of veterinary medicine and therefore should be called animal physical rehabilitation.
I commend you again for highlighting the importance of conservative management as an option for dogs with CCL tears. I recently attended one of the largest veterinary conferences in the world, the North American Veterinary Conference. We had an entire day devoted to veterinary rehabilitation and as part of that, there was a full lecture on conservative management of the CCL patient. The room was almost completely full. Many veterinarians realize that surgery is not the only option and many were looking for answers to give owners who choose to say “no” to surgery.
Evelyn Orenbuch, DVM, CCRT, CAVCA, CVA (pending) rehabvets.org