What is a CCL tear in dogs?

The cranial cruciate ligament is the dog equivalent of the human ACL, a band inside the knee that keeps the joint stable. When it tears, the knee becomes painful and unstable. It is the most common orthopedic injury in dogs and the leading cause of hind-limb lameness.

Why do dogs tear their cruciate ligament?

In most dogs it is not a single traumatic accident. The ligament degenerates slowly over months to years until it frays and gives way, sometimes during ordinary activity. That is why it often happens in both knees and why genetics, body weight, and conformation matter more than one bad jump.

Will my dog tear the other knee too?

Often, yes. The American College of Veterinary Surgeons reports that 40 to 60 percent of dogs that rupture one cruciate later develop the same problem in the other knee, frequently within a year or two, which reflects the underlying degenerative nature of the disease.

What does CCL surgery cost for a dog?

It varies widely by region and technique. A TPLO, the procedure usually recommended for larger and active dogs, commonly runs about $3,500 to $7,000 per knee in the US, while a lateral suture repair for smaller dogs is often cheaper. These are market estimates, not fixed prices.

Can a dog recover from a CCL tear without surgery?

Some dogs, especially small or less active ones, can be managed with weight control, rest, anti-inflammatories, and rehabilitation. But because the knee stays unstable, pain and arthritis often persist, and surgery is generally the most reliable way to restore function in larger dogs.

Cruciate Ligament Tears in Dogs (the Canine “ACL”): Risk, Surgery, and What It Really Costs

Here is the short version: the most common orthopedic injury your dog can have is a torn knee ligament, the cruciate, which is the dog version of the human ACL. The surprising part is that in most dogs it is not a sudden accident. The ligament slowly degenerates over months or years and then gives way, which is why so many dogs eventually tear the other side too. The good news is that the condition is well studied, the surgery works, and you can plan for it. This guide covers why it happens, which repair the evidence favors, and what it costs.

The most common orthopedic injury in dogs

Cranial cruciate ligament disease is described by the American College of Veterinary Surgeons as one of the most common reasons for hind-limb lameness, pain, and knee arthritis in dogs.¹ It is common enough to be a genuine economic force: one analysis estimated that treating it cost US owners well over a billion dollars in a single year.⁵ If your dog suddenly starts favoring a back leg, holding it up, or slowing down on walks, the cruciate is one of the first things a vet will check.

It usually is not an accident

This is the part that reframes everything. In people, an ACL tear is typically a sharp sports injury to a healthy ligament. In dogs, the ACVS is blunt that sudden trauma to an otherwise healthy ligament is very rare. Instead the ligament degenerates slowly, weakening over time until it frays and ruptures, sometimes while the dog is just trotting across the yard.¹

That single fact explains the rest of the disease. Because the cause is a process rather than an event, the same dog often blows out the second knee later. The ACVS puts that risk at 40 to 60 percent of affected dogs, frequently within a year or two of the first.¹ It also means prevention is less about avoiding one risky leap and more about the slow-moving factors that wear a ligament down.

40–60%

of dogs that tear one cruciate ligament later tear the other knee, reflecting the disease's degenerative nature

American College of Veterinary Surgeons

What raises the risk

Three levers stand out in the research. The first is breed and genetics. A UK primary-care study of more than a million dogs found markedly higher odds in certain breeds, with the Rottweiler near the top, and the disease runs in families.² The second is body weight. Extra pounds load the joint with every step, which is one more reason our guide on keeping a dog lean keeps coming up across this site.

The third is more nuanced: when a dog is neutered. A large UC Davis analysis found that neutering some large and giant breeds before about a year of age was associated with a higher rate of cruciate injury, in some breeds several times the rate seen in intact dogs.³ The effect is breed and size specific, so this is a conversation to have with your vet about your particular dog rather than a blanket rule.

The other thing that often tears: the meniscus

The knee also holds a cushioning pad of cartilage called the meniscus, and an unstable knee tends to grind it. A meaningful share of dogs with a cruciate rupture have meniscal damage as well, with studies reporting figures that range widely depending on how the joint is examined. The practical takeaway is that a vet usually checks and addresses the meniscus during cruciate surgery, because leaving a torn meniscus behind is a common reason a repaired knee still hurts.

Which surgery, and does the type matter

There are two broad families of repair. The older approach, the lateral suture or extracapsular technique, places a strong artificial band outside the joint to mimic the ligament. The newer family changes the geometry of the bone itself so the knee no longer needs the ligament to stay stable, the most common being the TPLO (tibial plateau leveling osteotomy).

For larger and more active dogs, surgeons generally favor the bone-leveling procedures, and the ACVS notes the lateral suture may not be the best choice for big, young patients.¹ A veterinary evidence review comparing the two found better limb function and owner satisfaction with TPLO than with lateral suture.⁶ Across techniques, the ACVS reports that roughly 85 to 90 percent of dogs regain good long-term function.¹ Smaller dogs often do well with the simpler repair, which is part of why cost varies so much.

What it costs

Surgery is the main expense, and the range is wide. The figures below are typical US market estimates rather than fixed prices, and they climb in high-cost cities and fall in rural areas.

TPLO (larger, active dogs): commonly about $3,500 to $7,000 per knee, including anesthesia, the procedure, and follow-up imaging.
Lateral suture (smaller dogs): often lower, roughly $1,200 to $3,000 per knee.
Remember the second knee: with a 40 to 60 percent chance of the other side going, it is wise to budget as if this could happen twice.

$3,500–$7,000

typical US range for a TPLO on one knee; plan for the real possibility of needing it on both

Aggregated 2024–2026 U.S. veterinary cost guidance; varies widely by region

What conservative care can and cannot do

Surgery is not the only path, especially for small or older dogs. Weight loss, rest, anti-inflammatory medication, and structured rehabilitation can improve comfort and, for partial tears, sometimes buy time. The honest limit, per the ACVS, is that the knee stays unstable without surgery, so pain tends to persist and the joint keeps heading toward arthritis.¹ For a larger dog, surgery is usually the more reliable route back to a normal life.

What to do this week

If your dog is limping on a back leg, holding it up, or sitting with one leg kicked out to the side, book a vet exam rather than waiting it out.
Get an honest read on your dog's body condition, because weight is one of the few cruciate risk factors fully in your hands.
If you have a large-breed puppy, ask your vet about the best timing for neutering for that specific breed.
If one knee has already torn, watch the other leg closely and plan financially for the real chance it follows.

A torn cruciate sounds like a catastrophe and feels like one in the moment, but it is one of the most treatable orthopedic problems in dogs. Knowing that it is usually a slow degeneration, not a freak accident, changes what you do: keep your dog lean, take early limping seriously, and go in with a clear-eyed plan, including for the knee that has not torn yet.