Cruciate Ligament in Dogs: Symptoms & Treatment

Cranial cruciate ligament dog injuries are to blame for most cases of hind limb lameness in dogs. These ligaments have the same function as the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) in human knees. Knee joints tend to be prone to injuries. Just as ACL tears are especially common in athletes, cruciate ligament tears are common in dogs.  

Let’s look at what pet parents need to know about torn cruciate ligaments in dogs, symptoms to watch out for, some treatment options, and cruciate ligament surgery costs.

What Are Cruciate Ligaments?

The cruciate ligaments are an essential part of a healthy dog’s knee, also called a stifle joint. There are two of them: the cranial cruciate ligament (CCL) and the caudal cruciate ligament (CaCL). These ligaments are bands of tissue that wrap around and stabilize the dog’s knee. They allow the knee to open and close as a hinge joint, but keep it from moving side-to-side.¹

The two ligaments cross over each other in the stifle joint to keep the femur and tibia bones stacked correctly. They’re called cruciate ligaments because they “cross over” each other in the knee joint, resembling a crucifix.

How Cruciate Ligament Injuries Happen

Cranial cruciate ligament injuries can be chronic or acute. Both are painful and may cause lameness.

Chronic injuries are more accurately called cruciate ligament disease. This is when there's a slow degeneration of the ligaments because of repeated trauma or arthritis. They’ll often be stretched or twisted repeatedly, causing wear and tear. Chronic cases can cause slow-onset lameness and may be noticed by your vet before symptoms become apparent.¹

Acute injuries happen when a dog overloads the joint, causing trauma. This often happens when suddenly shifting direction mid-run during a walk or playtime. This is a similar injury to an athlete tearing their ACL in a soccer game. Injuries like this are immediately noticeable, and usually the dog will yelp, collapse, or limp after getting hurt.¹

Cruciate Ligament Risk Factors

Some dogs are more at risk than others for a cruciate ligament tear. Dogs that are overweight are at a higher risk, because there’s more mass and pressure on the joint. Large dogs such as golden retrievers, Labrador retrievers, rottweilers, Newfoundlands, and German shepherds are also especially prone to this condition.²

Further, dogs with a cruciate ligament injury on one leg are at a higher risk for developing one in their other hind leg. This is because they’ll begin to favor the uninjured leg, putting more weight and strain on it.

Symptoms of Cruciate Ligament Failure

A dog’s femur slides forward into the tibia when cranial cruciate ligament tears, which usually causes pain and could restrict the dog’s mobility. Over time, this friction between the femur and tibia can wear down both bones, potentially leading to osteoarthritis.³ There are several indicators of this injury such as limping and reduced muscle mass around the joint, along with other signs that could point toward a chronic or an acute injury.⁴

Like with a CCL, an acute injury to the CaCL causes sudden pain. The dog may limp, cry out, and only put a tiny amount of weight on the foot of the injured leg.

Meanwhile, a chronic CaCL injury usually wears down the ligament over time. This could potentially cause reluctance to exercise, muscle atrophy, and lameness.

Diagnosing Cruciate Ligament Failure

Generally, a veterinarian will diagnose a cruciate ligament rupture with a physical examination. They’ll look at the dog’s medical history, test for potential lameness, and test for a “drawer sign.” This is when the vet holds the femur and gently pulls the tibia forward. If it slides forward like a drawer, that’s a clear indication of a CCL tear.²

The vet may also take X-rays of the knee. This lets them see the extent of the ligament deterioration, as well as check for arthritis and other possible concerns.

Treatment Options

Many dogs with a cruciate ligament injury will need surgery. In some cases, small breeds under 22 pounds may be prescribed strict cage rest and pain medications or therapy. Your vet could recommend just rest and pain management if the cruciate ligament is only partially torn, but your dog may still need surgery to stabilize the knee joint if it doesn’t heal properly.¹

There are a handful of different surgical techniques used to stabilize the knee. All of them include examining the inside of the knee and removing any cartilage or ligament fragments before stitching it back together.

Each type of surgery is a different way of keeping the femur and tibia stacked properly without sliding around. This way the knee can be weight bearing and properly hinge open and closed without wear and tear.

Extracapsular repair

An extracapsular lateral suture (ECLS) is the procedure that’s been around the longest to repair a dog’s knee ligament. It uses suture material as an artificial ligament to stabilize the knee.³

Essentially, a veterinary surgeon drills two holes: one on the femur bone and one on the tibia bone. They then wrap the suture from the back to the front of the knee joint and anchor it in the two drilled bone holes.³

Recent advancements in suture materials, bone anchors, and bone tools have made this repair even more successful. However, this surgery is primarily an option for smaller or mid-sized dog breeds.³

Extracapsular repairs generally cost between $800 to $2,500.⁵

Tight Rope® procedure

The Tight Rope® procedure is similar to an extracapsular repair because it’s also externally stabilizing the joint. It is also an option for small to mid-sized dogs, but not often recommended for larger breeds.³

In this procedure, a veterinary surgeon drills two bone channels, one through the femur and one through the tibia. Both channels go from one side of the bone to the other, to run the suture material through. This provides a stronger anchor for the suture, which they wrap around the joint similarly to the extracapsular repair.³

Tight Rope® procedures usually cost between $750 to $1,500.⁵

TPLO surgery

A tibial plateau leveling osteotomy (TPLO) surgery actually realigns the knee, rather than just stabilizing it as the previous two procedures do. This is especially important in larger dogs who put more weight on their knees than their smaller counterparts.⁶

In a TPLO surgery, a veterinary surgeon cuts through the tibia bone, making a semicircle slice. They then rotate the top piece to make the angle between tibia and femur level. Once it’s level, they’ll use a metal plate and screws to stabilize it. This reconstruction of the knee joint prevents the sliding that happens when a ligament is torn.⁶

TPLO surgery tends to cost between $2,500 to $6,000.⁵

TTA surgery

A tibial tuberosity advancement (TTA) surgery is also a great option for large dog breeds. Similar to a TPLO surgery, it recreates the knee joint, restoring proper function.⁶

For a TTA surgery, a veterinary surgeon makes a slice in the tibia. They then put an orthopedic spacer between the two pieces of the tibia, to push the bone up and fix the angle. They’ll then attach a metal plate to the front of the tibia to hold it in place. The two pieces of hardware help to fix the knee’s alignment and stabilize it.⁶

TTA surgery usually costs between $3,000 to $6,000.⁵

Recovering From Cruciate Ligament Surgery

After any dog cruciate ligament surgery, it’s crucial that you obey any recovery instructions your vet provides. This may include administering pain medications, anti-inflammatory medications, crate rest, icing the incision, and limited exercise. Recovering dogs will need 6 – 8 weeks of low activity after their operation. Full recovery usually takes 3 months.¹

Pet Insurance Could Help Cover CCL Injuries

Cranial cruciate ligament dog injuries can ring up a high vet bill. Surgical options range from $750 to $6,000, and that’s not counting any follow-up appointments, therapy, or pain medications.⁵ Dog insurance may help cover CCL injuries and all they entail.⁷

A mixed dog from Texas tore her CCL, and needed surgery. The procedure cost about $3,500 and MetLife Pet Insurance covered the entire vet bill.⁸ Your dog could have this type of coverage. Depending on the specifics of your policy, cruciate ligament injuries may be subject to a 6-month wait period from when you get your MetLife Pet Insurance.⁹ So get started with your free quote today!