It often starts subtly — a slight limp, a hesitation before jumping, or a pet struggling to use one of their back legs. While these signs could indicate temporary soreness or a minor sprain, they may also point to a much more serious issue, a torn cranial cruciate ligament (CCL).
This common injury can significantly affect a dog’s or cat’s ability to walk, run or even stand comfortably. Luckily, there’s a surgical solution that can help restore their mobility — Tibial Plateau Leveling Osteotomy (TPLO) surgery.
Dr. Katherine Barnes, a clinical associate professor at Texas A&M’s College of Veterinary Medicine and Biomedical Sciences, shares the signs of CCL tears, how TPLO surgery works and why choosing the right surgeon is so important.
Knee’ding a Fix
Joints are where bones meet, forming a complex network of connections that allow the body to move smoothly and in many different ways. In the knee joint, called the stifle joint in pets, one small structure plays a big role in keeping everything stable — the cranial cruciate ligament.
“The CCL is similar to the ACL in people,” Barnes said. “It connects the thigh bone (femur) to the shin bone (tibia), thereby allowing the leg to bear weight and preventing those bones from moving beyond their normal range.”
Because the stifle joint is essential for leg movement and weight bearing, it’s under constant pressure, making it especially vulnerable to wear and tear. That’s why CCL injuries often happen gradually, as the ligament weakens over time.
When the ligament tears, the bones in the leg are no longer secure and can slide beyond their normal range, especially since the top of the shin bone — which supports most of the body’s weight — has a natural slope in dogs.
“Without the CCL holding the bones in place, that slope causes instability that leads to pain, inflammation and the development of arthritis over time,” Barnes said. “If you notice your pet limping, swelling around its knee, or even a clicking sound when they walk, it’s best to visit the veterinarian for an exam to see if a CCL tear is to blame.”
Any pet can experience a CCL tear, though it’s most often seen in dogs, especially large, active ones.
A Surgical Solution
When a CCL tear leaves the knee unstable, TPLO offers an innovative solution.
“Instead of replacing or repairing the damaged ligament, TPLO changes the anatomy of the knee to eliminate the need for the ligament entirely,” Barnes said. “This is done by making a curved cut in the top of the tibia to flatten its weight-bearing surface. The bone is then secured with a specialized bone plate and screws.”
This adjustment prevents the abnormal forward movement of the tibia that typically happens when the CCL is torn, thereby stabilizing the joint without the need for the CCL to hold the bones in place.
From start to finish, the entire process — including preparation, anesthesia, surgery, X-rays and waking the pet — typically takes a few hours.
“Clipping the fur and scrubbing the leg beforehand is a critical step, as it helps decrease the risk of postoperative infection,” Barnes said. “Before surgery, X-rays are performed to confirm the diagnosis and rule out any other sources of pain, such as from a fracture, and blood work is done to ensure the patient is healthy for anesthesia. Xrays are also taken after surgery to ensure that the implants are well-positioned before waking the patient up.”
Setting The Stage for Success
TPLO surgery offers excellent outcomes — but success starts with choosing the right surgeon. As a highly technical procedure, TPLO demands precision and expertise at every step.
Board-certified surgeons are specially trained to provide this level of care.
“Board-certified surgeons go through years of additional specialized training,” Barnes said. “They complete an internship, do a three- to fouryear surgery residency and pass board exams — all specifically focused on surgery.”
This advanced training ensures that every phase — from preparation to implant placement to guiding owners through the recovery process — is handled with the accuracy needed to support safe healing. Without that expertise, small technical errors that can increase the risk of complications are far more likely.
TPLO is a major procedure, but when handled with the right care, it gives pets the best possible chance at regaining comfort and mobility.
