The cranial cruciate ligament is a piece of tissue within the knee joint that keeps the joint stable when a dog walks. The angle of a dogs knee joint is very steep compared to humans, which means the cruciate ligament is placed under much higher stress throughout a dog's life. Over time, this ligament can become inflamed due to stress, which sets off secondary osteoarthritis within the knee joint. Eventually, the cruciate ligament will rupture causing a lot of instability and pain. There are lots of ways to repair a knee with a diseased or ruptured cruciate ligament, however, most specialists agree that the TPLO, or tibial plateau levelling osteotomy, is the superior method of repair with the best return of function.
Ivy was booked in for her X-rays so that we could confirm the diagnosis of a ruptured cruciate ligament, as well as ensure her other knee and hips were looking normal. Measurements were taken from the X-rays so we could perform the TPLO. In a TPLO, a circular cut is made in the tibia (see image below), the bottom bone that makes up the knee joint. This section is rotated so that the angle of the knee is no longer steep, and aims to be perpendicular to weight-bearing forces. This means the tibia (bottom bone) is no longer unstable or able to slide forward.
Ivy had her TPLO procedure and recovered incredibly well. As a part of the procedure, Ivy’s joint was opened and the cartilages that sit between the two knee bones, called the meniscus, were inspected to see if they were damaged. Because a ruptured cruciate ligament results in instability of the knee joint, the sliding back and forth of the two bones can result in the tearing of the meniscus. If this has occurred then the torn portion needs to be removed, which we performed in Ivy’s knee.
When a dog has cruciate disease, it always leads to rupture, so the sooner a dog has the joint repaired the better prognosis that they will recover and get back into their normal routine. If your dog shows any signs of intermittent limping on one of their back legs, sitting down with their legs to the side instead of sitting squarely, or an unwillingness to jump into the car or run, then an appointment with one of our vets will allow us to examine their joints and make sure they healthy.