Cruciate disease is the most common orthopedic condition in dogs and often requires surgical treatment.
Inside the dog’s knee there are two crossing ligaments joining the femur and the tibia. These are known as the cranial and caudal cruciate ligaments. The cranial cruciate ligament is similar to the ACL (or anterior cruciate ligament) in humans. The cranial cruciate ligament is one of the most important stabilizers inside the canine knee joint. It prevents forward motion of the tibia out from under the femur. A complete or partial rupture of the cranial cruciate ligament leads to joint instability and lameness. If left untreated, this can result in severe arthritis as unnatural movement damages protective joint cartilage. There is also a cartilage like structure called the meniscus that sits between the femur and tibia bones. It is important for shock absorption, position-sensing and load-bearing and is often damaged when the knee is unstable secondary to cruciate disease.
How is cruciate rupture diagnosed?
During an examination, your veterinarian will feel both knees and test for unusual instability in the knee joint. If your veterinarian suspects ligament rupture has occurred they will recommend taking X-rays under sedation to further assess the knee.
Why does cruciate ligament rupture occur?
There are multiple factors that can contribute to the rupture or tearing of the cranial cruciate ligament. These include age, obesity, and breed/genetic predisposition. Medium to large breed dogs over the age of four are more likely to be affected, but it can be seen in small dogs and rarely in cats as well. In most cases, degeneration of the ligament occurs gradually over months or years before rupture. Unlike humans, (think football players that injure their ACL) sudden traumatic rupture of an otherwise healthy ligament is rare in dogs. Due to the degenerative nature of the disease in dogs it is common for both knees to be affected and up to 60 per cent of dogs that have cruciate disease in one knee will have the other knee have issues in the future.
Treatment of cranial cruciate ligament rupture
In the vast majority of cases, surgical treatment of cruciate ligament rupture is recommended and will give the best outcome for recovery and return to function. There are a number of different surgical techniques and options available. Your veterinarian will guide you to which option is best for your dog.
The recovery process
Postoperative home care is crucial to optimal recovery and it takes a number of months before dogs can return to regular activity. Premature, uncontrolled or excessive activity risk complete or partial failure of the surgical repair. Owners need to follow the postoperative recommendations giving to them by their dog’s surgeon and be prepared to keep their dog confined and under leash control during the recovery period. Weight management is also very important and maintaining an ideal lean body condition can be achieved by monitoring food intake and moderate regular exercise after the rehabilitation period is complete.
Dr. Kim Jones joined the North Peace Veterinary Clinic care team in 2009 after graduating with distinction from the Western College of Veterinary Medicine.