People commonly rupture the anterior cruciate ligament (ACL). It is the most common orthopedic injury seen in dogs, but is more properly called the cranial cruciate ligament (CCL). In dogs, the injury is often a slow, progressive degeneration of the cruciate fibers as apposed to an acute traumatic injury seen in people. Dogs can have a combination of cruciate ligament degeneration, or partial and complete tears, hence the name “Cranial Cruciate Ligament Disease”.
The CCL is one of the most important stabilizers within the knee joint. The CCL runs in a diagonal direction connecting the femur (thigh) and tibia (shin) bones, within the knee joint. The meniscus is a cartilage like structure between the femur and tibia bones. Its function is to provide shock-absorption and cushioning to the joint. The meniscus can be also damaged when the CCL is damaged.
Illustration of the anatomy of the dog’s knee: Blue = cranial cruciate ligament; Red = meniscus; Green = caudal cruciate; the insert shows a ruptured cranial cruciate ligament (also note that the shinbone is displaced forward and is crushing the meniscus)
Cruciate ligament degeneration can be caused by a combination of factors including: age, obesity, conformation, physical condition, genetics and breed. Unfortunately 40%-60% of dogs that have cruciate disease in one knee will develop disease in the other knee. Partial cruciate tear is common, and most of the time will progress to a complete tear and possible meniscus damage.
Diagnosing a cruciate ligament injury in your pet is made through a combination of techniques. Gait analysis to watch your dog walk, palpation of your pet’s knee and x-rays. X-rays of the knee help to determine the degree of arthritis in your pet’s joint, to help plan for surgical correction as well as to rule out any other concurrent injuries.
There are numerous surgical treatment options to correct a cruciate ligament tear. Variables we consider when making recommendations for treatment include pet’s age, size, activity level, degree of knee instability and affordability. We currently offer 2 main surgical treatments for CCL tears:
Illustration of the concept of the TPLO procedure which involves making a circular cut in the tibial plateau and rotating the contact surface of this bone
Illustration of the TPLO procedure utilizing bone plates and screws. Image provided by Synthes (USA); copyright notice: 2012 © Synthes, Inc. or its affiliates. All rights reserved.
Many patients following surgery make a near complete recovery, and return to normal activity following the 12 week recovery period. Many of our patients return to work and have been used for agility and hunting. Pain related to arthritis may become evident as the patient ages but can often be managed with joint supplements, anti-inflammatories and weight management.
Images courtesy of: https://www.acvs.org/small-animal/cranial-cruciate-ligament-disease