What Should You Do If Your Dog Tears an ACL?

If you are unlucky (like me), and your dog tears its anterior cruciate ligament (ACL) be forewarned; you are in for a bumpy ride.  I love my dogs.  They are healthy, happy and very active labs.  But 18 months ago, when my Sophy tore her ACL I was just so unsure of what to do for her.  So I did my research.  Read one internet site and they tell you you can “cure it” by rest and confinement.  Read another site and they say you should immediately take your dog  in for surgery to minimize arthritis later in life.  Well I made my decision for Sophy and was convinced it was the proper one.

Fast forward 12 months and my other dog Chester tore his ACL in a “sports injury”.  Having already gone through this once with Sophy, I did the research all over again.  This time I made the mistake of telling someone of my decision and they verbally attacked me.  They said “how can you play God with the life of your dog”.  At first I was horrified and felt ashamed; then I just got angry! Who was she to judge me.  But it was because of that one comment that I started the Raising Healthy Dogs site.

And I have one crucial piece of news for you….we will all make mistakes.  Just like our parents made mistakes raising us, we will make mistakes raising our dogs.  All we can do is make decisions for their welfare based on imperfect and often biased information and the resources we have available to us.  So if you dog tears an ACL, do your research, speak with your vet and a surgeon if necessary and shut out all the negative noise.  Following is an overview of the problem and various treatment options. It was written by a vet and reviewed by a surgeon.  For anyone interested, I chose TPLO for both dogs.  If anyone want so talk about the experience or has questions, let me know.  I am more than happy to share my experiences and tips for recovery.


To understand what happens when a dog ruptures his cruciate ligament, and how it can be treated, we need to learn a little about the anatomy of the knee joint.

Your dog has two cruciate ligaments in his knee. They criss-cross the space between the femur and the tibia (hence their name), and prevent these bones moving forwards and backwards against each other. Between the two bones lie two little crescents of cartilage called menisci (singular is meniscus). These act as shock absorbers when your dog walks and runs, and protect the cartilage at the end of the two bones.

Rupture of the anterior cruciate ligament (ACL) is by far the most common injury that can occur to a dog’s knee. There are two common scenarios that occur when this ligament ruptures. Firstly, a young active dog hurts his knee while he’s running around playing games or chasing birds. Secondly, an elderly dog with weakened ligaments or a degree of arthritis may sustain the same injury because the ligament has degenerated with age. In both cases, there is a sudden onset of lameness, and the leg is so painful that they can’t put their foot down.

If your dog has ruptured his cruciate ligament, you have several treatment options to choose from. In most cases, surgery is necessary to prevent excess movement in the joint, which will inevitably lead to arthritis.   Surgery also allows your veterinarian to tidy up any ragged edges to the menisci, which can cause ongoing discomfort.

Let’s have a closer look at the different ways of treating a cruciate rupture in your dog.

Non-Surgical Treatment

If your dog is small, you may choose to do nothing. When the acute pain resolves, little dogs may recover enough to be comfortable with being given pain relieving anti-inflammatory medication when required. Natural joint support products such as glucosamine and green lipped muscle extract can also help. It can take over 4 months before they recover to this level. This treatment option is really only appropriate for dogs under 30lbs, as heavier animals put too much stress on their knees. Keep in mind also that long-term use of anti-inflammatory drugs can have effects on your dog’s stomach and kidneys.

Prolotherapy can be useful in helping to manage a cruciate rupture if surgery isn’t an option. This procedure involves injection of a solution into the knee which causes scarring around the joint. This scarring helps to stabilize the joint and reduce excess movement. It’s a controversial procedure; it can have good results, but it can also lead to complications such as excessive inflammation. To get the best outcome from this procedure, it should be done by an orthopedic specialist.

If your budget allows it, surgery is still the best option for all cases of cruciate rupture in dogs.

Extracapsular Repair

“Extracapsular” means outside the joint capsule, so this method of repair doesn’t involve any implants or modifications to the inside of the knee joint.

After the joint has been opened, and any damaged bone, ligament and meniscus have been removed, a strong suture is placed on the outside of the knee to take the place of the torn ligament. The suture is passed behind the fabella, a small bone that sits right at the back of the knee near the bottom of the femur, and then through a hole drilled through the front of the tibia. It is tied sufficiently tightly to stabilize the knee, while still allowing a normal range of movement.

Post-operative care involves 8 weeks of rest, then a gradual increase in exercise. Over time, scar tissue will develop around the knee joint, and this will reduce excess movement. The suture itself often breaks within 12 months after the procedure, but by then the knee should be held stable by its own tissues.

This procedure is quick, and inexpensive when compared to the more invasive methods of repair. It can work well in small dogs, and is particularly useful in puppies, where you don’t want to make changes to the bones themselves while they are still growing.

Tightrope Procedure

This is another extracapsular method of repair, but in this case, a hole is drilled through the bottom of the femur, and the top of the tibia. A double band of strong Fiber Tape is passed through these holes and down the outside of the joint, and serves to replace the ruptured cruciate ligament.

This procedure is relatively easy to perform, and is also more affordable than the repairs that involve cutting and manipulating the tibia. It has been shown to be effective in treating cruciate rupture in most sizes of dogs, however many veterinarians prefer to restrict its use to dogs that weigh under 70lbs.

Tibial Plateau Leveling Osteotomy (TPLO)

TPLO is the most commonly recommended method of repairing a ruptured cruciate ligament in dogs. It relies on cutting and rotating the tibia in such a way that the dog’s own weight bearing stabilizes his joint. After the tibia is cut and moved, a metal plate is screwed to the tibia to keep it in its new position.

This is a very complex procedure, and should only be undertaken by veterinarians who have had special training in how to do it correctly. It is expensive, costing several thousand dollars. There are several reasons for this:

It should only be performed by an orthopedic specialist.

  • Multiple x-rays are necessary to make sure the cut in the bone is done in the right place.
  • The metal screws and plate are expensive.

This procedure is suitable for dogs of all sizes. It is particularly appropriate for larger dogs over 50lbs, and for athletic dogs such as those involved in agility competition. It’s not the best choice for dogs whose bones haven’t finished growing, because the physical changes to the tibia can lead to their own set of problems as the bones continue to grow.

As with other methods of cruciate repair, exercise must be restricted for 8 weeks after surgery, and most dogs return to full function after 3-4 months.

Tibial Tuberosity Advancement (TTA)

This is another repair method that relies on biomechanics to stabilize the knee joint. The idea behind this relatively new procedure is that if the top of the tibia and the patellar ligament (the ligament from the kneecap to the front of the tibia) are realigned at 90 degrees to each other, the joint will be stable when the dog walks.

Again, the tibia is cut, but this time the front of the tibia where the patellar ligament actually attaches is removed, and moved forward. It is held in position by metal implants, and the gap between the front of the tibia and the rest of the bone is filled by a bone graft.

Although it doesn’t sound like it, the TTA procedure is less invasive, and has similar results to the TPLO surgery. It too is expensive, because of the metal implants and because it must be done by a board certified specialist. Dogs that have had TTA surgery often appear to recover quicker than those with a TPLO, however by 6 months post-operatively, both procedures have a similar outcome.

The TTA is suitable for all dogs, and which procedure your dog undergoes may just depend on your orthopedic specialist’s proficiency at each. You’ll find that some specialists prefer to perform a TTA, while others feel that they get better results from the TPLO procedure.

Post Operative Care

Your orthopedic surgeon will prescribe pain relief to keep your dog comfortable and will give you specific advice on how to care for him after his operation.

After surgery to repair a ruptured cruciate ligament, the most important thing you can do for your dog is to rest him. Ideally, keep him crated and only take him out on a leash to go to the toilet.

Most dogs feel quite well long before their bone has healed, and this is when many owners start to take them for walks or otherwise increase their activity. This can cause breakdown of the surgery, so it is vital that you follow your vet’s directions very carefully.

Post-operative physical therapy can be beneficial to dogs after this type of surgery. This can take the form of massage, hydrotherapy, and gently moving the leg through its range of motion. The results are reduced swelling and inflammation, and increased healing, which will improve your dog’s demeanor and attitude.

Conclusion for What Should You Do If Your Dog Tears an ACL

A ruptured cruciate ligament is a severe injury, that can have long-term effects on your dog’s well-being. Fortunately, it can be treated and in most cases, this results in a return to normal function.

There are two main factors which influence which treatment option is right for your dog.

  • Finances. Some procedures are more expensive than others, and your family budget will have a big impact on how your dog’s knee is repaired.
  • Your dog’s age and size. Some procedures are not appropriate for young dogs, and others are less likely to be successful in large breeds.
  • A third factor is your orthopedic specialist’s preference and their experience with each of the procedures.

Take the time to discuss your options with your dog’s surgeon, and together you will decide on how to treat your dog so that he again can enjoy going for a walk or playing with you in the park.


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