Canine Cruciate Ligament Injury (CCL/ACL)

Watch our CCL Summary Video here!

You might have heard about a human athlete that tore their ACL and how it took them out for the season. The ACL (anterior cruciate ligament) is responsible for stabilizing your knee, especially during high intensity activities that require your legs to twist or pivot. In dogs, this ligament is referred to as the CCL (cranial cruciate ligament) and the knee is referred to as the stifle, but it’s the same ligament with the same job and it can be just as devastating.

How Does This Happen?

The canine CCL often degenerates over time, leading to a partial or complete tear, though trauma to a healthy ligament from high impact twisting of the leg or hyperextension of the knee, can have the same result. In most cases, the dog’s CCL will slowly weaken until it eventually ruptures completely.

Within 1 year of injury, approximately 60% of dogs will rupture their other CCL.

In early stages (partial tears), your dog’s discomfort may be very subtle, such as putting less weight on the leg when standing or intermittent and very mild limping. As the ligament continues to degrade, your dog may start limping more, especially after activities like running or jumping. Your dog may take longer to rise up or sit down. Osteoarthritis, the gradual wearing away of cartilage, begins in the joint and can eventually lead to bone rubbing on bone. Dogs with painful, arthritic, unstable stifles often sit on their rump with the affected leg held out to the side to avoid bending the stifle as they would with a normal sitting position. As it becomes more and more painful to use the injured leg, they are likely to lose muscle mass on that side and put additional stress on their other legs which can cause further compensatory injury. 

Who Is At Risk?

There are several variables that can increase a dog’s risk for CCL disease. Obesity and poor body condition play a huge role, so keeping your dog at a lean, healthy weight and regularly exercised can help prevent this type of injury. “Weekend Warriors” and high intensity activities, such as wrestling with other dogs or agility sports, are common contributors to CCL rupture.

Some breeds, like Labrador Retrievers, Staffordshire Terriers, Rottweilers, Boxers, and Mastiffs are predisposed, but any dog can be affected. Anecdotally, CROC has seen a high incidence of CCL disease in Labradoodles, Goldendoodles, and similar crosses.

The Weekend Warrior spends most of their time hanging around the house with minimal exercise but then goes all out with high intensity and/or long bouts of exercise only every once in a while. This might look like being a couch potato during the week while parents are working and then going on a 10 mile run alongside a bicycle on Saturday. A recipe for trouble!

There is emerging research regarding the time of spaying or neutering and the correlated risks for orthopedic conditions like CCL disease.

The hormones produced by the sex organs are largely responsible for telling the growth plates when to close at physical maturity. When these hormones are removed before the growth plates close, there is only a very small bit of hormones being produced elsewhere in the body, so the bones continue to grow long after they were supposed to stop. Dogs spayed or neutered at a young age are frequently lighter in build, taller and leaner, with narrower skulls. The theory of how early spaying/neutering causes increased risk for CCL disease is that due to the bones growing beyond their intended size, the knee joint becomes unbalanced, therefore putting abnormal strain on the Cranial Cruciate Ligament.

So, your dog has a CCL tear. What do you do now?

When the ligament is damaged, the knee is no longer stable and bones start to move and rub in ways they were not meant to, causing significant pain, difficulty walking, and osteoarthritis to develop. The meniscus, a cartilaginous structure between the tibia and femur, is often damaged from the abnormal strain causing significant pain. For this reason, it is best to surgically correct this condition as soon as possible.

Surgery is often a scary and expensive endeavor, so why is it the Gold Standard (how veterinary medicine labels the best course of treatment)? Once the CCL has ruptured, there is no fixing it.

The joint’s condition will only continue to worsen as osteoarthritis sets in and increased strain is placed on the other ligaments, causing increased pain.

Partial tears may be medically managed for a time, but will more than likely progress into a full tear. Osteoarthritis will form in the joint regardless of surgery, but patients who have surgical correction sooner rather than later will have less pain and arthritis than those who went without surgery or even those who pursued surgery months or years after the CCL ruptured. Keep in mind most dogs with a CCL tear are likely to tear their other CCL. Preventing undue stress on the uninjured leg can potentially give you and your dog more time before the other CCL ruptures.

Can I brace my dog’s knee instead of pursuing surgery?

We absolutely understand the desire to avoid surgery but for most cases, we will strongly advise against the use of a brace. While a brace might provide some degree of stabilization, it does so by restricting movement of the joint, reducing the knee’s Range of Motion. A joint that is without its full Range of Motion will become more stiff, more inflamed, and more painful. This restriction in movement also causes significant muscle atrophy. Muscles that aren’t exercised waste away. Just like if you have your leg in a cast for several weeks, when the cast finally comes off, your leg muscles will have atrophied from lack of use. Reduced musculature will only make your dog's situation worse because the joint will have even less support when it needs it most.

Surgical Solutions

Example of TPLO

First and foremost, make sure your dog’s surgeon is a board-certified veterinary surgeon that specializes in orthopedics. The official credential of a board-certificated veterinary surgeon is Diplomate, American College of Veterinary Surgeons, often presented as DACVS or ACVS Diplomate. These veterinarians perform complicated surgical procedures every day and have all the unique tools and years of experience to give your dog the very best chance of successful surgery and an excellent recovery. There are 3 surgical techniques to address CCL ruptures. Based on your dog’s anatomy and any concurrent problems, your dog’s surgeon will choose which technique will work best.

Tibial Plateau Leveling Osteotomy (TPLO)

The TPLO is the Gold Standard (best available) solution for a CCL tear. This surgery involves cutting a portion of the Tibia (the shin bone), rotating it, and securing it in the new position using a metal plate and screws. The new position will prevent the abnormal movement that occurs with a torn CCL.

Tibial Tuberosity Advancement (TTA)

As the TPLO has proven to be the most effective technique for CCL tears, TTA is falling out of favor because some dog’s bones are shaped in such a way that would make this surgery inappropriate or less likely to succeed. Like the TPLO, the TTA involves cutting into the tibia and using metal hardware to secure it. The tibial tuberosity is moved to change where the quadriceps muscles attach in conjunction to the knee to stabilize the joint. Since both surgeries are equally invasive and the TPLO has better success rates, we would not recommend use of this technique.

Extra-Capsular Suture Stabilization

This procedure can also be referred to as a Lateral Fabellar Suture Stabilization or the Fishing Line Technique. Rather than cutting into the bone or using metal hardware, this procedure attempts to “replace” the CCL with a strong suture.

Premature breakdown or failure of the suture is a very common complication with this technique, leaving a post-surgical patient with a painful and unstable stifle despite the cost and effort of the surgery.

While this approach is usually less expensive and less invasive, it is also best reserved for smaller breeds and older, less active dogs because there is a high rate of failure when used with medium or larger breeds and more active dogs. We generally do not recommend this technique because the body will eventually break down that suture material. The hope is that during the time that the suture was in place, the stifle will have developed enough scar tissue and bony changes to stabilize the joint. Unfortunately, osteoarthritis will form in the stifle, which will cause pain, limit full range of motion, and decrease functional use of the joint.

Post Operative Recovery

Recovery from stifle surgery can be challenging as it typically requires several weeks of strict exercise restriction to allow the bone to heal. Limiting your dog’s activity according to the surgeon’s recommendations is not optional.

Too much activity too soon can be devastatingly destructive to a bone that is healing; potentially causing failure to heal, fractures, or even requiring additional surgery to repair the leg.

Use of an e-collar (aka the cone of shame) is incredibly important as any licking of the incision/stitches is likely to cause a serious infection of a fresh orthopedic surgery site. Your dog’s surgeon will tell you when the e-collar is no longer needed. Pain medications and antibiotics are typically prescribed and should be given as directed. Do not stop or decrease these medications without consulting with the surgeon first. Some pets benefit from sedating or anti-anxiety medications during the recovery period to help keep them calm and less likely to over exercise.

It may be helpful to use baby gates to block off certain parts of your home during the recovery period, especially stairs or areas with slick floors. Good traction and controlled movements are key elements for safety and smooth recovery. If you have other pets in your home that typically play together, it is best to keep them separated during the first few weeks. Just like when we have a freshly broken bone, your dog will need to avoid any high-impact activities which sadly includes play time with housemates. Your surgeon may provide instructions for low-impact exercises as your pet heals. This may include Passive Range of Motion or standing exercises. Walks are typically restricted to slow and short outings, but can be increased each week as your surgeon recommends.

This dog has severe muscle atrophy on the left leg

Sticking to your pet’s prescribed exercises is important, not only to prevent over-stressing the surgical site, but also to maintain what muscle mass and flexibility they currently have.

Atrophy and reduced range of motion is the most common post-operative complication that we treat.

Prolonged disuse of a leg can cause Muscle Contracture, a condition where atrophy has become so severe that adhesions form between the bone, periosteal tissues (a thin layer of tissue that surrounds the bone), and quadriceps muscles, essentially locking the thigh muscles down and preventing normal movement of the leg. Muscle contracture is very painful and extremely difficult to resolve, often requiring multiple therapy sessions a week for several months to give a patient the best chance at regaining normal limb use.

Supplements

Dasuquin Advanced with MSM is an excellent daily joint supplement that many of our team members choose to use for their own pets. It includes Chondroitin, Glucosamine, and other ingredients to support joint health and it comes in a tasty, chewy treat, making it an easy addition to your daily routine.

Fish Oil added to your pet’s meals is another easy addition to help keep joints happy (and it helps their coat too!). Start with 500-600mg per day, then increase to 1000-1200mg per day. It is important to start slow with this as some pets may be sensitive and have GI symptoms if started too quickly.

Myos Canine Muscle Formula is a supplement containing Fortetropin, a natural bioactive supplement made from fertilized egg yolk. Myos has been credited with improving muscle health, helping to reduce muscle loss (atrophy) and helping regain muscle after surgery or with other disease processes. It has also been shown to help skin, coat, cognitive, and bone health.

Medications

Adequan (Polysulfated glycosaminoglycan) is a series of injections that stimulates cartilage healing, slows the progression of osteoarthritis, and decreases pain and inflammation. It begins with an initial series of 8 injections with one injection given every 3-4 days. Once that is complete, many pets can drop down to a maintenance schedule of one injection every 1-6 months. For larger dogs, this can be a costly investment to get started, but we have seen significant improvement for many dogs using this medication. If you have concerns about giving your dog injections, be sure to speak to your veterinarian for options like an in-person demo or having their staff perform the injections for you. You can also speak to the CROC team.

Common NSAIDS - Rimadyl (carprofen), Metacam (meloxicam), Deramaxx (deracoxib), and their Generics are Non-Steroidal Anti-inflammatory medications that can be extremely helpful for managing pain and inflammation and since many generics exist, it can be easier to find one that fits your budget. They can have long term side effects to the liver and kidneys so regular bloodwork is strongly recommended to catch any change in organ function early. They must also be given with food! Some pets don’t tolerate these medications well and can have serious GI side effects like stomach ulcers and gastrointestinal bleeding. It is important to monitor your dog for any signs of vomiting, diarrhea, or dark stools while on these medications. Some pets REALLY like the taste of the flavored tablets so store these medications with caution, securely out of reach of your pet.

Galliprant (grapiprant) is a newer type of Non-Steroidal Anti-inflammatory that has less side effects than the more widely known NSAIDS listed above. It is reported to have less effects on liver, kidneys, and GI tract and can be safely used alongside a wider selection of other medications. Because it is newer and a more specific medication, it is generally more costly than the above listed NSAIDS that have been around longer.

Neurontin (gabapentin) is a medication primarily used to treat nerve pain, though it can also help with anxiety. Many pets experience some level of drowsiness when they first start this medication, but they usually become accustomed to it and return to their normal energy level after some time. Besides sedation, other side effects are extremely rare. This medication is a good option for pets that cannot tolerate NSAIDS and it can also be used alongside NSAIDS and many other medications.

Tramadol is a synthetic opioid that has been commonly used to treat moderate to severe pain in dogs. Newer studies on this medication show that it may be less effective than previously thought, with only a small fraction of dogs getting any pain relief from it. Side effects from Tramadol include sedation, vomiting, diarrhea, constipation, and loss of appetite

Librela (bedinvetmab) is the newest Osteoarthritis treatment in the US; a once monthly injectable medication only for use in dogs. It must be administered by your veterinarian and may take up to 6 weeks for observable results. Librela is a monoclonal antibody (a protein that has been engineered to bind to a single target) that targets Nerve Growth Factor which helps reduce pain caused by Osteoarthritis. It can be extremely effective for the right patient.

Side-effects and adverse reactions from Librela are still being discovered.

Dogs with neurological conditions should not be given Librela as it is likely to worsen neurological conditions.

Some Owners are not aware that their dog has a neurological condition until their dog has an adverse reaction to Librela. Adverse neurological reactions may include: generalized weakness, inability to control bladder and/or bowels, stumbling, knuckling, dragging paws, and/or inability to walk. Should your pet experience any of these symptoms, Librela should not be given again until your pet has been evaluated by a Veterinary Neurologist. It may take up to 3 months for a patient to recover from a Librela-induced neurological decline although patients with Degenerative Myelopathy are extremely unlikely to regain any lost ability.

Dogs with inflammation caused by auto-immune conditions should not be given Librela as it is likely to make these conditions worse.

Studies on Librela were performed on young dogs free from other health conditions. Consider that senior dogs struggling with arthritis pain are the most likely patients to receive Librela but are also nearly guaranteed to have other conditions that may be complicated by Librela. Due to potentially severe side-effects, we recommend that your pet be thoroughly evaluated before starting Librela. This should include bloodwork and radiographs at a minimum and may require evaluation with a neurological or orthopedic specialist. Electing to give your pet Librela without prior diagnostic screening is a gamble!

Librela is not indicated to treat CCL disease or post-operative pain, nor is it labeled for treating pain related to any other types of chronic pain other than Osteoarthritis.

Librela does not cure Osteoarthritis. Dogs on Librela sometimes feel so good (since they can’t feel the pain) that they overdo it and cause further injury to themselves. It is best to introduce Librela alongside a structured exercise plan to avoid injury and only after thorough diagnostic screening to rule out auto-immune and neurological conditions.

What About Rehab?

Remember that Rehab cannot fix a CCL rupture. However, initiating therapy after surgery can improve their recovery by addressing their muscle atrophy, increasing their range of motion, stimulating healing, and relieving any pain that might remain. Your dog’s surgeon will decide when your dog can begin therapy, but they may want to take follow up x-rays to confirm appropriate healing beforehand.

Every case will be different, so recommended commencement of therapy can range from 2 to 8 weeks after your dog’s surgery.

Post-operative Rehab consists of multiple modalities to address the entire body; not just the surgical leg. Your dog has been compensating for the affected leg by walking differently and putting more weight on their other legs. This often means that their other legs are overworked and sore. Back pain is not uncommon after spending so much time walking with poor ergonomics. Therapy often begins with Thermotherapy, Massage, and Stretching. Thermotherapy and Massage help to relax tense muscles and increase blood flow to the tissues. Stretching is necessary to maintain your dog’s full range of motion in all joints, but should not be performed until after Thermotherapy and Massage. Laser therapy is an excellent tool to promote healing and relieve pain and inflammation.

However, recovery takes more than just the “feel goods”. The goal is to restore your dog’s comfort and mobility, which will not improve without exercise.

Low impact Target exercises will be prescribed to your dog in order to address any deficiencies and encourage normal limb use. You will be instructed to have your dog do some of these exercises at home on a daily basis. Hydrotherapy using an Underwater Treadmill provides a high resistance but very low impact workout, encouraging muscle growth needed to support the joint and keeping the unaffected leg strong.

Take note that Hydrotherapy in an Underwater Treadmill is recommended, but due to less benefit and higher risks, swimming is not.

Our article The Deep Dive Into Swimming provides a visual and more detailed explanation for this, but we’ll briefly explain here too. When dogs swim, they generally paddle fiercely with their front legs while keeping their back legs tucked up alongside their body. This type of movement means they are over-working their already strained front legs and barely working the back legs that actually need the exercise. If they do kick their back legs, it is generally in a quick, spastic movement that does not encourage muscle building but does put more stress on a fresh orthopedic surgery.

The CROC Team has treated multiple post-op patients with severe complications caused by swimming, such as migrated surgical screws and avulsion fractures of the tibia.

Long Term Care

Even with surgery, your pet will develop Osteoarthritis (albeit slower than a dog that did not have surgery) and as they get older, it will only become more challenging for them to build muscle and lose weight. By keeping them lean and well-muscled from the start, you are giving your dog a solid foundation for a longer, more active, and healthier life.

The most impactful thing you can do at home to keep your pet comfortable and active is to maintain a lean body weight and good musculature.

Visit our article Body Condition Score & Canine Weight Loss to learn more. Joint supplements with Fish Oil, Glucosamine, Chondroitin, and MSM may be helpful to stimulate cartilage matrix production and inhibit enzymes that break down cartilage. For more information about Osteoarthritis care, check out our article Crunchy Doggos - Managing Osteoarthritis.

If this is your dog’s first CCL injury/surgery, you should prepare yourself for the likelihood that your dog’s other knee will also be affected and require surgical intervention. The above-described care tips may also help your dog’s intact CCL stay that way longer, but ultimately there is no way to prevent a tear.

What If Surgery Is Not An Option?

Because surgery is the only way to resolve a CCL injury, it will always be the top recommendation. However, there are some circumstances that make surgery a poor choice. Often, financial constraints are the first to come to mind. We get it; it’s an expensive option! However, without surgery, your dog will require long term treatments (Rehab, medications, etc) to try to control their pain.

If your dog is a young dog, you will likely spend at least the same, but likely more money on these “band-aids” than if the surgery was performed at the beginning.

If your pet is a senior or geriatric pet, it may not make sense to put them through anesthesia and a big surgery. Pets with co-morbidities like heart disease, liver shunts, or clotting disorders can also be high-risk anesthetic candidates. Certain auto-immune conditions may complicate your pet’s ability to heal or fight off infection.

In these cases, your goal will be to maintain your pet’s comfort and mobility as best as possible. As the cartilage in their knee degrades, they will begin to experience more pain and therefore be more likely to rely on their other legs instead, setting them up for compensatory injury or rupturing their other CCL. Pain medications, supplements, and Rehab are all good options for relieving pain and inflammation. More information on these options is available in our above mentioned “Crunchy Doggos - Managing Osteoarthritis” article.

To Summarize

CCL ruptures are painful and can be expensive to resolve but they don’t have to keep your dog on the sidelines forever. Utilizing services from a board-certified veterinary surgeon and a certified veterinary rehab specialist is likely to give your dog the best results.

While braces and medications might be appealing solutions, they will not resolve your pet’s condition and could potentially make it worse.

With surgery and the right home routine, your dog can enjoy good, pain-free mobility even after a CCL injury. For dogs that cannot undergo surgery, there are options to help control their pain but surgery is still the most effective solution for this condition. 

If you still have questions about Cranial Cruciate Ligament injuries, our team of licensed veterinary professionals at Canine Rehab of Orange County is happy to consult with you. CCL injuries are among the most common conditions that we see and we aim to help you find the best options for you and your dog. In some instances, we start therapy before surgery to maintain comfort and muscle mass as much as possible. We frequently see CCL patients after surgery to help them achieve the best and fastest recovery. Feel free to reach out to us with any questions or if you would like to move forward with a consultation, visit our New Patients page to get started.