Torn Knee Ligament in Dogs (CrCL Tear)

If your dog is suddenly limping or refusing to put weight on a back leg, a torn cranial cruciate ligament (CrCL) is one of the most likely culprits. It’s the canine equivalent of a human ACL tear, and it’s one of the most common orthopedic injuries vets see in dogs. It can happen gradually or suddenly, and it’s painful.

Understanding what’s going on, what your options are, and what recovery looks like can help you make confident decisions for your dog.

What is a CrCL tear?

The cranial cruciate ligament (CrCL) runs inside the knee joint and plays a key role in stabilizing the joint during movement. When it tears, either partially or completely, the knee becomes unstable, the bones shift against each other in ways they shouldn’t, and the surrounding structures, including the cartilage, start to take damage.

Unlike in humans, where ACL tears are usually caused by a single traumatic event, CrCL injuries in dogs most often develop gradually. The ligament degenerates over time until it tears, sometimes triggered by a specific movement, but really the result of a longer process. This is why the condition is often referred to as cranial cruciate ligament disease (CCLD) rather than just an injury.

One important thing to know upfront: studies suggest that dogs who tear one CrCL have a 40 to 60% chance of eventually tearing the other one too. Keeping that in mind as part of your long-term planning matters.

What are the symptoms of a torn CrCL?

Recognizing the signs of a CrCL tear in dogs can help you act quickly. The symptoms vary depending on whether it’s a partial tear or a complete rupture, but here’s what to look for:

• Sudden hind leg limping or non-weight bearing on a back leg
• Sitting with one leg stuck out to the side
• Swelling around the knee joint
• Muscle atrophy (loss of muscle mass) in the affected leg
• A clicking sound when walking
• Lameness that seems to improve with rest but returns during activity (for partial tears)

If your dog shows any of these symptoms, it’s best to consult your vet as soon as possible. Early intervention can reduce the risk of further damage and ease your dog’s pain.

What are the causes of CrCL tears in dogs?

CrCL injuries often develop gradually due to wear and tear on the ligament over time, rather than sudden trauma. Here are some key factors that increase the risk:

• Breed predisposition: Large breeds like Labradors, Rottweilers, St. Bernards, and Mastiffs are more prone to CrCL issues.
• Obesity: Extra weight puts strain on a dog’s joints, increasing the likelihood of a tear.
• Age and genetics: As dogs age, their ligaments can weaken. In some breeds, genetics play a role in ligament degeneration.
• Poor conditioning: Dogs that are less active or poorly conditioned may have weaker joint support.
• Spay/neuter timing: Some studies suggest that early neutering may elevate CCLD (cranial cruciate ligament disease) risk.

Traumatic tears from a sudden impact or misstep do happen, but they’re less common than the gradual degenerative form.

How is a CrCL tear diagnosed?

Your vet will start with a physical examination and specific tests designed to detect knee instability:

• Cranial drawer test: The vet holds the femur (thigh bone) steady and attempts to move the tibia (shin bone) forward. Abnormal movement is a strong indicator of a CrCL tear.
• Tibial compression test: Assesses abnormal movement in the joint when the leg is flexed at the ankle.
• X-rays: Don’t show the ligament directly, but reveal joint swelling, early arthritis changes, and other findings consistent with CrCL disease.
• Advanced imaging: MRI or arthroscopy may be recommended in complex cases to get a detailed view of the ligament and surrounding structures.

Most dogs need to be sedated for these tests to ensure accuracy and keep them comfortable. Your vet will also check for meniscal damage, as the medial meniscus (a piece of cartilage inside the knee that acts as a shock absorber) is commonly injured alongside the CrCL.

What are the treatment options for CrCL Tears?

For most dogs, surgery is the recommended treatment. The right procedure depends on your dog’s size, weight, and activity level.

Surgery	How it works	Best suited for
TPLO (tibial plateau leveling osteotomy)	Changes the geometry of the knee joint so it no longer relies on the CrCL for stability. A curved cut is made in the tibia and the bone is rotated and plated into a new position.	Large and giant breeds; the most commonly performed procedure for dogs over 20kg
TTA (tibial tuberosity advancement)	Advances a section of the tibia forward to neutralize the forces that destabilize the knee.	Large breeds; an alternative to TPLO with comparable outcomes
Extracapsular repair (lateral suture technique)	Stabilizes the joint using a strong synthetic suture placed outside the joint capsule. Less invasive but less durable under high loads.	Smaller dogs (typically under 15 to 20kg) or less active dogs

If meniscal damage is found during surgery, it will be addressed at the same time; either by repairing or removing the damaged portion.

For very small dogs or cases where surgery isn’t possible, conservative management with strict rest, anti-inflammatory medications, and joint supplements may be considered, but it’s less effective at preventing long-term joint damage and arthritis.

What is the recovery and care needed after surgery

Recovery from CrCL surgery takes time, and the first few weeks are the most critical. Here’s what to expect:

• Weeks 1 to 8: Strict exercise restriction. Short, leashed toilet walks only. No running, jumping, or stairs.
• Weeks 8 to 16: Gradual, controlled return to activity as directed by your vet.
• Months 4 to 6: Most dogs return to full activity around this point, though individual recovery varies.

Things that make a real difference during recovery:

• Physical rehabilitation: Guided exercises help rebuild muscle and restore normal movement. Many vets refer to a canine rehabilitation specialist for this.
• Home modifications: Ramps instead of stairs, blocking off furniture, keeping your dog on a lead during outdoor time, and non-slip surfaces on hard floors.
• Weight management: Keeping your dog at a healthy weight reduces stress on the healing joint and on the opposite knee.
• Joint supplements: Glucosamine and omega-3 fatty acids are commonly recommended, though always check with your vet before starting anything new.

Some degree of arthritis in the affected joint is likely over time, even with surgery. But surgery significantly slows its progression and gives your dog a much better long-term outcome than leaving the knee unstable.

Is it covered by pet insurance?

Yes, CrCL tears are covered under Lemonade Pet’s base accident and illness policy, as long as the condition isn’t pre-existing. That includes eligible costs like diagnostic imaging, surgery, and follow-up care that’s typically part of treatment.

Recovery from CrCL surgery often involves a structured rehabilitation program to help your dog regain strength and mobility. Lemonade’s Physical Therapy add-on can help cover the cost of those sessions, making it easier to follow through on the full course of recovery your dog needs.

Getting a policy in place before any symptoms or injuries occur is the smartest move. Once a condition is considered pre-existing, it won’t be eligible for coverage.

Before We Go

A CrCL tear is a tough diagnosis, but with the right treatment and a solid rehabilitation plan, most dogs recover well and get back to doing the things they love. If you don’t have a pet insurance policy in place yet, it’s worth taking a few minutes to explore your options. Getting a quote is straightforward, and having coverage before anything happens puts you in a much stronger position when it matters most.

Torn knee ligaments frequently asked questions

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