When To Put A Dog Down With Torn ACL? (Explained)

Reviewed On November 11, 2022 by Dr. Liza Cahn, DVM 

If your dog has been diagnosed with a cranial cruciate ligament injury (equivalent to a torn ACL in people), you may feel overwhelmed and unsure of your treatment options. In most cases, a costly surgery is recommended to provide the best outcome for your pup, but for various reasons euthanasia may be a last resort. Below are the details you’ll need to help you make this difficult decision. 

If your dog has a knee injury such as a torn ACL, a veterinarian will be able to help you determine whether or not euthanasia is the best course of action. While a costly surgery is generally the recommended treatment, there are medical treatment options available as well, and euthanasia should only be considered as a last resort or in extreme circumstances.

Factors to consider include if surgery is possible, available options/success of medical management, your dog’s age/health/quality of life, and your financial burden. You also may want to consider euthanasia for a dog with torn ACL if they’ve stopped eating, drinking, or are unable to get around. 

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What Is A Torn ACL In Dogs?

Let’s start with the basics, as the knee is a complicated joint! Among other structures, there are two fibrous bands known as the cranial and caudal cruciate ligaments, which cross over each other to stabilize a dog’s knee joint. A torn ACL occurs when the ligament connecting the front of the tibia to the back of the femur partially or completely rips or tears. This is most commonly caused by acute trauma when a dog suddenly changes direction or twists while running, and the ligament cannot compensate as quickly as needed. This is normally seen in young, active dogs. The medial meniscus is often damaged as well in this type of injury. Ligament damage may also occur more slowly over time in older large breed dogs, as the ligaments degenerate and slowly stretch before tearing. It is also important to note that dogs with a history of cranial cruciate injury are more likely to develop the same injury in their other leg at some point in the future.

This injury may be more common in certain dog breeds. It’s also a common injury with professional athletes, which is probably why it sounds familiar to you! In dogs as in people, this is a severe injury causing significant pain and lameness, and something that must be addressed as soon as possible by your vet. 

What Are Torn ACL Symptoms In A Dog?

Since dogs aren’t exactly the best communicators, it’s up to us humans to figure out what is happening with our canine family members. Common symptoms of a torn ACL may include:

  • Pain indicators
  • Swollen stifle (knee) 
  • Difficulty standing and walking
  • A sudden change in gait
  • Not putting weight on one of the hind legs

Most of these will come on quickly and seem very out of the ordinary. A torn ACL is very painful in dogs, so these symptoms will be easy to detect. Some dogs will become more aggressive, too, especially if you try to check out what’s going on.

Your vet will diagnose a torn ACL based on history, physical exam, and x-rays. On exam dogs will generally be toe-touching or non-weight-bearing lame on the affected back leg, and may have a notable cranial drawer sign. X-rays may show effusion (fluid) in the stifle joint and arthritic changes (depending on how long the injury has been present).

Can A Dog Live With A Torn ACL?

Yes, dogs can live with a torn ACL. There weren’t as many treatment options for dogs with ACL injuries back in the day, so most vets recommended euthanasia since this is an excruciating and painful condition.

Nowadays, experts are better equipped to offer treatment options and determine how bad the tears are through detailed scans and exams. All of this means a better treatment plan and prognosis for your dog.

What Treatments Are Available For Dogs With Torn ACLs?

If your dog is diagnosed with a torn ACL your vet will discuss treatment options with you. The two approaches to treatment include medical management (involving limiting movement, pain medications and anti-inflammatories, plus or minus other recommendations) versus surgery (often involving referral to a specialist). In most cases surgery is the recommended and most successful form of treatment. Treatment options may include: 

  • Limiting movement
  • Pain medications and anti-inflammatories 
  • Physical therapy
  • Weight reduction
  • Leg bracing
  • Surgery

Limiting Movement

Limiting movement along with other medical management (pain medications and anti-inflammatories) to decrease inflammation may be beneficial in cases where the tear is minor, in smaller breed dogs, and those with less active lifestyles. If a dog is not a good candidate for surgery and anethesia this is also a worthwhile treatment option to try. 

This generally involves approximately six weeks of strict rest where your dog is confined to a crate or small room and only taken outdoors on a leash to eliminate. They should not run, jump, walk up or down stairs, or play during this time. As this may be especially difficult for a young active dog, some vets may prescribe sedatives to facilitate rest. If your dog is doing well after this period of rest, you may slowly return to normal activity level, however this may be hindered by the development of arthritis in the future. 

Pain Medications and NSAIDs

Pain medications will be recommended regardless of the path you choose. As mentioned, a torn ACL is very painful! Medications may include nonsteroidal anti-inflammatory drugs (NSAIDs), gabapentin, tramadol, and others. A multimodal approach will often involve different types of pain medications working together to help keep your dog comfortrable. 

Physical Therapy

While physical is extremely beneficial in healing after surgery, it is unlikely to be successful alone. It may be worth considering if surgery is not possible for various reasons including financial constraints or concurrent disease processes making anesthesia too risky. 

Weight Reduction

Obesity is a risk factor for development of arthritis and musculoskeletal injuries in dogs. Keeping your furry friend lean and healthy will be beneficial for their bones and joints. If your dog is overweight speak with your vet about feeding recommendations. This often involves meal feeding instead of free feeding, cutting back on the amount of food fed, cutting back on treats or switching to lower calorie options, or trying a prescription veterinary diet for weight loss. 

Leg Bracing

This can be an option to help your dog keep his quality of life if a pet parent is looking to avoid surgery. Companies such as OrthoPets make specialized braces that are put on the injured leg to help minimize the pressure on the ACL and restrict movement around it. This will help the dog keep moving as needed while stabilizing the knee joint, however the success rate has not yet been determined in these cases and this option is unlikely to be curative. 


In modern-day, and in most cases, surgery is the best option for dogs with a torn ACL. There are several surgical techniques that may be used, and often involve referral to an orthopedic surgeon. 

Extracapsular stabilization is the least invasive surgical option, and does not require specialized equipment. In this procedure an artificial ligament is placed outside the capsule of the knee to joint to provide stabilization, and is highly successful in small dogs. 

Tibial Plateau Leveling Osteotomy (TPLO) and Tibial Tuberosity Advancement (TTA) are more invasive, more expensive, have higher rates of complication, and require specialized equipment and training. However they are generally the preferred technique for young, active, and large-breed dogs. 

Your veterinarian or orthopedic surgeon will be able to discuss these options in more detail and help determine the best course of action for your individual dog. Surgery is a large financial commitment, and will also involve extensive recovery time including exercise restriction and physical therapy. However it is also the option that provides the best chance for your dog to return to their normal activity level and maintain their quality of life. Keep in mind that arthritis later in life and possible injury of the other leg are likely even if surgery is successful, however there are lots of management options available for this. 

What Is The Average Cost Of ACL Surgery For A Dog?

It will vary depending on the surgical technique used, the services included, and the size and health of your dog. However, most ACL surgery quotes tend to fall between $2,000 to $4,000. These often will include basic pain medication and post-op care as outlined above, and often check-ups at set intervals afterward to see how your dog is doing. 

However, there are also additional charges to think about, such as physiotherapy, extra pain medication (if needed), specialized equipment to help keep your dog’s activity limited while they recover, and additional treatment for arthritis and injury in the other leg that may occur in the future. Cost can range widely based on your dog’s situation, but your vet can often provide more personalized estimates!

What Is The Dog’s ACL Surgery Success Rate?

The success rate for a dog’s ACL surgery is very high, often between 80-90%. This means that most dogs return to good or excellent function after surgery. For this reason surgery is the recommended treatment for most ACL injuries in dogs. Success rate may vary depending on factors such as age, health profile, and the severity of the injury. Your vet will be able to explain these to you! 

How To Decide If You Should Euthanize A Dog With a Torn ACL

This is an extremely difficult and personal decision that should be discussed with your vet and other experts that are available to you. Euthanasia should be considered if a dog is in severe pain that is unable to be managed and is significantly affecting their quality of life. However, in almost all cases there are other options that should be considered first, such as pursuing surgery, medical management, or surrendering your pet to your vet clinic or someone who may be able to provide treatment. Factors to consider include: 

  • Quality of life
  • Available treatment options and prognosis 
  • Your dog’s age and health
  • Your available funds

Quality Of Life

As you’ve read, most specialists agree that ACL surgery gives your dog an excellent quality of life. However, this is not true for every dog, nor is every dog a candidate for surgery. 

If surgery is not possible and medical management is not successful at controlling your dog’s pain, then euthanasia could be considered. This may be especially true for dogs who have ACL injuries in both hind limbs at the same time. If your dog is not eating, drinking, or moving this is a poor quality of life. If they are miserable and unable to care for their most basic needs, you need to factor this into your decision.

Available Treatment Options and Prognosis 

It is important to discuss with your vet the treatment options that are available, financially feasible, and your goals of treatment. They may be able to work with your situation to come up with an appropriate plan. 

Your Dog’s Age and Health 

If you have a senior pet with multiple concurrent disease processes, they may not be a candidate for surgery. For example joint issues, previous injuries, obesity, and other systemic conditions like diabetes or cancer complicate recovery and increase risk of anesthesia. While age is not a disease, unfortunately some pet parents may be reluctant or unable to spend a large amount of money on a senior dog. In these cases every effort should be made to try medical management options. 

Your Available Funds

This is not a fun discussion point, but it is imperative to keep in mind! If you can’t afford the surgery and required post-op care, you need to have an honest discussion about this with your vet. They may be able to help discuss options for financing such as CareCredit or borrowing from a friend or family member. If your dog is young and otherwise healthy your vet may not feel comfortable euthanizing for financial reasons alone, and may discuss other options with you such as surrendering your dog or rehoming them. 


How Long Can A Dog Go With A Torn ACL?

Dogs can go months or years with a torn ACL, but it’s not recommended. As soon as you notice any of those symptoms above, get your dog to a vet right away. The sooner it’s caught, the easier you can treat it. 

Although symptoms may seem to improve, if left untreated it will quickly lead to additional joint damage and arthritis. Simply “ignoring it” isn’t going to do anything but cause your dog a lot of pain and make the eventual fix be much more expensive and intensive. 

Can A Dog With A Torn ACL Walk?

Most likely a dog with a torn ACL will be capable of movement. That movement will involve limping or dragging the impacted leg, though, as most injuries cause a non-weight-bearing lameness. If both knees are injured at once that is another story. Their instinct will be to keep the weight off the leg with the injury, and it’s important not to force them to do otherwise.

How Much Pain Is A Dog In With A Torn ACL?

A dog with a torn ACL will be in a lot of pain. This is why, as mentioned, vets will recommend some form of pain medication as soon as possible. 

Can A Dog Recover From Torn ACL Without Surgery?

Some dogs, especially smaller breeds and less active animals, can do well with medical management. However surgery provides the best success rates for return to normal function and activity level. Medical management involving strict rest may take approximately six weeks. With or without surgery these dogs are likely to develop arthritis, however surgical repair will help minimize this. All dogs with ACL injury are also at higher risk for injury in the other leg. 

How To Care For A Dog With A Torn ACL

When looking to do what’s best for your dog when they have a torn ACL, your treatment is going to focus on a few factors based on your veterinarian’s advice:

  • Administering the pain medications as directed
  • Limiting movement as directed by your vet
  • Following any post-operative instructions for rechecks and physical therapy 
  • Being patient throughout the process 

Other than that, it’s going to be mostly about following your dog’s signals and understanding that you’ll have to get used to watching for problems in the future. A torn ACL is a serious injury and will need proper check-ups and treatments even down the road after the initial injury has passed.

If you are interested in physical therapy or massage ask your vet for recommendations or a referral. They may be able to demonstrate stretches and exercises that you can work on at home. Alternative treatment such as acupuncture may also be beneficial in reducing pain and inflammation. 

Can I Get A Leg Brace For A Dog With A Torn ACL?

Custom leg braces are available, however their efficacy is uncertain. A leg brace should never be used as the only care method for your dog after a torn ACL, of course, but it may be beneficial in conjunction with other medical management. 

In Conclusion – A Note From a Veterinarian 

In most cases the recommendation for treating a torn cranial cruciate ligament is surgery. Medical management may be recommended for less active small-breed dogs, those with underlying health issues that make surgery and anesthesia too risky, and in those cases where surgery is not financially possible. 

As veterinarians our goal is to keep our patients happy, healthy, and free of pain. A torn cranial cruciate ligament is a serious injury and major source of pain. If pain is unable to be managed and is affecting quality of life, then euthanasia is a valid option no matter how heartbreaking it is for those involved. However, before electing euthanasia all other options should be explored, whether this involves surgery, medical management, or surrender/rehoming. 

Unlike many disease processes, this injury is common in young, healthy, active dogs, and the recommended treatment is a large financial commitment which can catch many pet parents off guard. For these reasons it is best to plan ahead for emergency situations or consider pet insurance

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Andre Neves

Hi, I'm Andre and I'm the owner of Sula the Border Collie. I love writing about this amazing dog breed here. I joined the Council to be able to reach and educate more people on the joy of having a pet dog.