The Cranial Cruciate Ligament (CCL) is a ligament in the canine knee that helps keep the joint stable. It is similar to the ACL in people.

Recent research suggests that dogs can have a genetic predisposition to CCL weakening or degeneration, leading to an eventual tear. Other factors, such as developmental, anatomic, and hormonal, may also contribute to this degeneration. Tears in the CCL cause the knee joint to become unstable. This instability can also damage the menisci, or shock absorbers in the knee. Approximately 40% of dogs who tear their CCL will also have a meniscal tear. Because of the genetic predisposition to ligament degeneration, 50% of dogs that injure one CCL will go on to injure the other side.

Your primary care veterinarian, emergency veterinarian, or veterinary surgeon can diagnose a CCL tear with the following:

• Clinical history. Some CCL tears seem to happen abruptly after vigorous running, jumping, or playing, causing your dog to cry out in pain the second it happens. In other cases, the tear is less obvious because the CCL degenerates over time. You may see signs like stiffness after exercise, intermittent or consistent limping (lameness), and popping noises as the knee joint moves.
• Physical examination. Your veterinarian will observe how your dog walks for any signs of lameness. He or she will also manipulate your dog’s knee to check for signs of instability and pain. If the tibia (shinbone) moves forward in relation to the femur (thighbone), a CCL tear can be diagnosed.
• X-rays: X-Rays help rule out other causes for lameness and knee pain. They also may show changes associated with CCL tears, such as joint swelling and arthritis.
• Arthroscopy: Arthroscopy involves insertion of a sterile camera into the knee joint to visualize its structures, including the CCL and menisci. It is performed while your dog is under general anesthesia. Not every facility has access to this technology, but at AESC, we confirm the diagnosis of CCL tear using this minimally invasive technique.

The TPLO (tibial plateau leveling osteotomy) was developed to stabilize the canine knee joint after a CCL tear. This surgical procedure involves changing the biomechanics of the knee by cutting and rotating the tibia to stabilize the joint. A stainless steel plate is then affixed to the bone to allow the cut to heal.

Because the CCL cannot heal on its own, the knee joint will remain unstable without surgery. The instability results in pain, inflammation, arthritis, and possible meniscal damage. The associated discomfort results in more severe lameness and subsequent muscle atrophy.

An early, mild form of the injury may be managed with activity restriction, pain medication, and physical rehabilitation. Unfortunately, these treatments do not fix the knee joint's instability. Moreover, because CCL disease in dogs is a degenerative and progressive condition, the ligament will continue to break down over time. Once a dog is constantly limping or completely unable to stand on the affected leg, surgery is usually the best option.

Although dogs can live with a torn ACL, their quality of life will be negatively affected. Partial tears can be managed with activity modification and pain medications, but the lameness and discomfort will likely worsen with time. Once the disease has progressed to a complete tear, it becomes very challenging to treat the associated pain without surgery. If both CCLs become injured, a dog may have a difficult time getting up and walking, and running and playing becomes impossible.

Alternatives to TPLO surgery include lateral suture (extracapsular repair), TightRope, or TTA surgeries. We recommend the TPLO because it has the highest success and lowest complication rates. If complications occur, they are generally easier to manage.

Unfortunately, joint injections have not yet shown much benefit in healing the cranial cruciate ligament, and they do not eliminate the need for surgical stabilization.

Stifle (knee) braces can be considered. However, many dogs simply do not tolerate them. Some dogs will refuse to walk on the leg that is wearing a brace. They may be stubborn, but they may also be onto something, because studies have shown braces to be inferior to TPLO surgery for knee joint stabilization. Stifle braces can also be frustrating because long term use predisposes dogs to skin wounds and rub sores.

With effective pain management, dogs can undergo major surgery relatively comfortably. Typically, the first 48 hours after surgery are the most painful, but pre-emptive (before the pain even starts) analgesia goes a long way in preventing postoperative pain. At AESC, our board-certified anesthesiologist performs ultrasound-guided nerve blocks prior to surgery, preventing your dog from feeling anything at all in the knee for about 18 hours. At the end of surgery, a long-acting numbing infusion is injected, which has been demonstrated to last for up to 72 hours. These two techniques greatly reduce the need for narcotics and their associated side effects. We do recommend hospitalizing TPLO patients overnight for a non-narcotic pain medication infusion. Overnight hospitalization also allows our overnight doctors to monitor and treat your dog for any breakthrough pain. In addition, we send your dog home with oral pain medications. AESC is open 24/7, and we are happy to answer any questions or concerns you have about your dog’s condition at any time.

With a knowledgeable and well-equipped anesthesia team, yes. Our board-certified anesthesiologist has extensive training and experience in anesthetizing pets with a variety of systemic conditions, such as heart disease. Our experienced anesthesia nurses have trained under her guidance for years. Because AESC is a multispecialty hospital, we have access to a wider variety of medications to help make anesthesia as safe as possible for pets that have heart disease. Our cardiology service is able to perform echocardiograms to diagnose and evaluate the severity of heart disease. Our board-certified radiologists can also accurately assess the status of your pet’s heart and lungs via chest x-rays prior to anesthesia to ensure it will be safe to proceed.

Full recovery from TPLO surgery depends on the severity of lameness before surgery, degree of CCL tear (partial or full), presence or absence of meniscal injury, and participation in a physical rehabilitation program. While bone healing takes 6-8 weeks, there are milestones to reach both before and after this time:

1. 10-14 days: The skin incision heals. Your pet is evaluated by us or your primary care veterinarian to ensure the skin incision has healed.
2. 8 weeks: The bone heals from the bone cut (or osteotomy, the “O” in TPLO). This is when we take complimentary x-rays of the knee to verify adequate bone healing. Once the surgeon has confirmed bone healing, dogs can resume more normal levels of activity.
3. 12-16 weeks: This is when most dogs can return to their normal activity.
4. 6-12 months: By this time, we expect postoperative patients to bear equal weight between the postsurgical and the normal leg.

TPLO surgery can cost anywhere from $3,000 to $8,000 depending on the geographic region, caliber of the facility where the surgery takes place, size of the dog, and what’s included in the price. TPLO surgery at AESC costs between $4800 to $5200 depending on the patient’s size. This cost includes x-rays, expert anesthesia, arthroscopic joint evaluation, meniscal treatment (if indicated), exceptional pain management, dedicated orthopedic surgical suites, overnight hospitalization, seamless follow-up care including 8-week recheck examination and x-rays, and rehabilitation consultation. We also accept ScratchPay, Care Credit, and pet insurance.

No. Although we commonly take referrals from primary care veterinarians, if your pet is showing signs of CCL injury, such as limping and pain, you can contact us to schedule a consultation. If you’re concerned about a more severe injury, like broken bones, our emergency service is open 24/7 with no appointment necessary.

This is probably our most frequently asked question! CCL rupture is one of the most common orthopedic injuries we see in our canine patients, and TPLO surgery is one of the most common orthopedic surgeries we perform here at AESC. Our three board-certified veterinary surgeons have collectively performed thousands of TPLO surgeries.