Frequently Asked Questions.
WHAT IS A TPLO?
TPLO stands for Tibial Plateau Leveling Osteotomy. It’s is a surgery performed on dogs suffering from a ruptured or torn ACL.
TPLO is THE most common surgery Dr. Zeltzman performs – by far.
WHAT IS THE ACL OR CCL?
The Anterior Cruciate Ligament (ACL) or Cranial Cruciate Ligament (CCL) is a very important ligament in the knee. It is called “cruciate” ligament because there is also a Caudal or Posterior Cruciate Ligament (PCL) that crisscrosses the ACL.
WHAT CAUSES THE ACL TO TEAR?
Most of the time, the tear is due to deterioration of the ligament. Rarely, like in football players, it is due to trauma.
Overweight pets are at higher risk. There is a genetic component since some breeds (e.g. Labradors, see below) are more frequently affected.
Why is my dog limping?
When the ACL tears, it causes pain and a wobbly knee. The shin bone slides forward as the thigh bone pushes on it during walking and running.
Your dog may not cry or whimper but will limp to avoid putting too much pressure on the leg. In other dogs, the leg may be held up in the air, occasionally or constantly.
What are the signs of a torn ACL?
The first sign is limping or holding the leg up. Other signs of a torn ACL include trouble jumping, decreased activity, difficulty going upstairs, and struggling to get up.
Over time, the lameness and muscle atrophy (or muscle loss) in the thigh will become more obvious.
You may also notice that your dog sits with the leg held straight out, instead of bent at the knee while sitting.
You may also hear a clicking or popping in the knee, a sign of a tear in the meniscus (a piece of cartilage in the knee).
What type of animals can have a torn ACL?
All dogs (and cats) of any age and all sizes can be affected. Certain breeds are known to have a higher risk of ACL tears.
Labradors (and mixes) are the most common breed. Pit bulls are the second most common breed. Other common breeds include Rotties, Goldens, German Shepherds (and mixes), Bulldogs, Boxers, etc.
Giant breeds include Mastiffs, Newfies, Great Pyrenees, St. Bernards, and Great Danes.
Dr. Zeltzman has performed thousands of TPLOs in dogs ranging from less than 5 pounds to more than 250 pounds.
SO DO ACL TEARS ONLY HAPPEN IN BIG DOGS?
This is a common misconception. The weight and breed of a dog have nothing to do with tearing the ACL, or with the need for a TPLO.
A steep angle (or slope) at the top of the shin bone (or tibia), also called a tibial plateau angle, often dictates the need for a TPLO.
For example, Westies and Cairn terriers are well-known for having a very steep angle, making them perfect candidates for a TPLO. This applies to other small dog breeds.
WHAT TYPE OF DOG IS MORE LIKELY TO TEAR THE ACL?
It can literally happen to any type of dog. Most are family pets.
Some of my patients are athletes: working dogs, hunting dogs, search and rescue, agility dogs, running companions, Frisbee dogs, dogs obsessed with tennis balls, etc.
I fully expect these patients to go back to work after their surgery.
WHAT ELSE CAN CAUSE LAMENESS IN THE BACK LEG?
We need to make sure that your dog is not affected by less frequent conditions, such as hip dysplasia (hip arthritis), ankle problems, cancer, etc. A common misconception is to assume that hip dysplasia is causing the problem when most often, the ACL is to blame.
When both happen at the same time, the knee almost always has to be repaired first. Then in most cases, the hip never needs surgery.
HOW DOES MY VET KNOW THE ACL IS TORN?
There are multiple tests your veterinarian or your surgeon can perform to help diagnose an ACL tear.
- The knee is wobbly (drawer sign, cranial tibial thrust).
- The knee is painful during the orthopedic exam.
- We feel too much fluid in the knee (effusion).
- There is scar tissue on the inside of the knee (medial buttress).
- The range of motion in the knee is decreased.
- When asked to sit, your dog will keep the affected leg straight out (sit test).
- X-rays show multiple signs: too much fluid, dislocation of the knee (cranial tibial thrust), bone spurs (arthritis), etc.
So even though we don’t see the ACL on X-rays, they are very important to confirm the diagnosis and eliminate other diagnoses (eg cancer). In addition, TPLO X-rays are required under sedation, in a very specific position, in order to plan the TPLO surgery.
WHAT IF MY VET IS NOT SURE IT’S A TORN ACL?
Occasionally, your family vet will not be 100% sure that your dog has a torn ACL. And that’s OK. At times, it can be very frustrating to confirm the diagnosis.
This is precisely the reason why your family vet works with a surgeon: to come up with the correct diagnosis and decide on the best course of action for your dog.
WHAT IS THE DIFFERENCE BETWEEN A PARTIAL TEAR AND A COMPLETE TEAR?
A partial tear of the ACL means that the ligament is not completely torn yet. Some people believe that a partially torn ACL does not need surgery. This is a big misconception that leads to prolonged pain, massive arthritis, and other problems.
Once an ACL starts to tear, nothing is stopping it. So a partial ACL tear virtually always ends up as a complete tear.
Remember, most ACL tears in dogs are not due to trauma but to deterioration and an angle at the top of the shin bone that is too steep.
Since we do not know how to stop the wear and tear or change the angle, surgery is needed to fix the problem.
WHAT ARE THE TREATMENT OPTIONS FOR MY DOG?
There are multiple options to treat an ACL – supposedly around 100 different ways!
The most common ones are nylon sutures (aka lateral sutures or extracapsular repair), TTA (Tibial Tuberosity Advancement), and TPLO, all of which I perform regularly. There is also the TightRope repair, the CBLO, the TWO, etc.
Please don’t believe in dogma and hype you read online or you hear from your neighbor. In my mind, who does the surgery is far more important than the type of surgery.
It is also critical to choose the ideal surgery for each patient, ie your particular dog. One “size” (or surgery) does not fit all patients.
What matters is to find a board-certified surgeon who performs the surgery often, with few complications and great outcomes.
DOES MY DOG REALLY NEED SURGERY?
Conservative or medical management will predictably lead to all kinds of problems. Here is an article where I listed 10 negative consequences of untreated ACLs:
Among those are: pain, arthritis, decreased range of motion, muscle atrophy and weight gain.
HOW URGENT IS SURGERY?
Surgery is not urgent. However, the longer surgery is delayed, the longer your dog is in pain (remember, limping = pain), the worse arthritis gets, etc. As time goes by, the ACL of the opposite leg can tear, and then you have a much bigger problem on your hands.
WHAT IS INVOLVED DURING TPLO SURGERY?
“TPLO X-rays” of the knee are taken in a very specific position, under sedation. They are measured to calculate the “slope” or angle at the top of the shin bone. This determines the entire surgery.
The top of the shin bone is cut, which allows turning it to its ideal position.
The two pieces of the bone are then held together with a stainless steel plate and 6 to 10 screws. The number of screws depends on the size of the patient.
HOW LONG DOES RECOVERY TAKE AFTER TPLO SURGERY?
It takes 8 weeks for the shin bone (or tibia) to fully heal. During this critical time, your dog needs to be strictly confined. I do not recommend a crate, except for small dogs.
A small room with no furniture and no steps is ideal for medium and large dogs. I encourage you to spend as much time as possible in the room to keep your dog company.
Short walks to eliminate are allowed as often as needed, with a leash and a sling.
X-rays are taken at 4 and 8 weeks to make sure the bone is healing correctly. Once the shin bone has healed, typically after 2 months, we can slowly increase your dog’s activity to rebuild muscles (rehab).
This schedule has proven to work very reliably for thousands of my TPLO patients over many years.
WHAT KIND OF MEDICATIONS WILL MY DOG NEED?
After surgery, an antibiotic and not one, but two pain medications will be provided.
CAN AN ACL HAPPEN IN THE OTHER LEG?
The ACL tears in the other leg in about 33% of patients. In Labradors, it happens about 50% of the time within 1 year after the first tear.
WHAT ARE THE RISKS OF SURGERY?
Like any surgery, there are possible complications with TPLO.
- We need to protect the repair to prevent failure of the repair. This is done by following the discharge instructions we will discuss, and you will receive in writing.
Your dog should be strictly confined to a small room, on ground zero, for 2 months, for that reason.
- We need to protect the incision to prevent an infection or opening up the incision. Your dog must wear a plastic cone (E collar) for the first 2 weeks until the staples are removed from the skin.
Nobody likes the cone, but it’s much less traumatic than an infection or an open incision!
Dogs with allergies or OCD who tend to lick their skin are more likely to lick the incision and cause an infection. At worst, this may mean removing the implants once the bone has healed.
- Implants need to be removed in about 1% of patients.
WHAT IS THE OUTCOME AFTER TPLO?
I expect 95% of my patients to be 95% close to normal 4 months after surgery (2 months of healing of the bone and 2 months of rebuilding muscles).
This is not just my opinion. This is based on my clients’ feedback.
Some dogs may not do as well for various reasons, including inappropriate care after surgery (i.e. breaking the rules), hip dysplasia, severe arthritis, and neurological conditions.
WHAT CAN I DO ABOUT THE ARTHRITIS?
We will discuss specific recommendations based on your particular dog. This may include weight loss, physical therapy, pain medications, controlled exercise, an “arthritis diet” and/or arthritis supplements.
MYTHS AND MISCONCEPTIONS ABOUT TPLO
- “Dogs don’t need surgery for ACL tears”: see the article above.
- “Small dogs don’t need surgery for ACL tears”: see the article above.
- “The TPLO plate can cause cancer”. One specific TPLO plate was linked to a few cases of bone cancer. This plate has been discontinued many years ago. I have never used it. Cancer caused by a metal plate is extraordinarily rare.
- “TPLO is only for small dogs”. Not true, some small dogs (including Westies & Cairn Terriers) are notorious for having a very steep angle at the top of the shin bone. This is best corrected by a TPLO.