Introduction
ACL injury in dogs refers to an injury to a ligament located in the knee joint (the knee is the next joint down from the hip in the rear leg). This ligament is referred to as the anterior cruciate ligament (ACL) or cranial cruciate ligament. ACL injuries are some of the most common ligament injuries that veterinarians see in dogs, and in most cases an ACL injury requires surgical repair coupled with lifestyle changes for a successful recovery.
Acute vs. Chronic ACL Injuries in Dog
Acute ACL injury is the most common cause of sudden rear limb lameness. These dogs typically hold the leg up in a somewhat bent position or they just rest the toe on the ground but do not bear a lot of weight on the leg. In more chronic, slowly occurring ACL injury, the dog may have a more subtle or intermittent limp of the rear leg.
What Causes ACL Injuries in Dogs?
ACL injuries are seen in young and old dogs, and this type of injury can occur suddenly or it can be a condition that slowly develops. Much like the basketball player who twists a knee during a game, a playful dog can tear a cruciate ligament during an extra exuberant period of play or exercise. Some dogs develop this condition because they are obese, or they have a large body frame, and the ligament tears from being stressed for a long period of time. In rare cases, a cruciate ligament injury can occur from an auto-immune disorder.
How ACL Injuries Affect Dogs
The cruciate ligament in a dog’s knee is an important structure because this ligament keeps the knee stabilized. When the ligament tears or ruptures, the two leg bones (the tibia and fibula), will begin to rub against each other causing pain and arthritis. Depending on the degree of the injury and the size of the dog, if no treatment is provided many dogs may eventually become permanently lame.
Diagnosing an ACL Injury
When a cruciate ligament tears, a dog often experiences sudden pain and lameness. A physical examination by a veterinarian, and possibly an x-ray, are usually the only diagnostic procedures needed to confirm a torn cruciate ligament. Routine blood work is often recommended as well to ensure the ligament did not tear as a result of an underlying medical condition.
Treating ACL Injuries in Dogs
For most dogs, surgery will repair the knee back to functioning form. However, lifestyle changes are also needed to lessen the chances of reinjuring the ligament or knee joint, and to help prevent ACL injury in the other rear leg (The fact is that about 1/2 of the dogs with ACL injury injure the ligament in the other rear leg within a few years of the first injury).
Recommended Lifestyle Changes
- Reduced exercise
- Weight loss
- Nutritional Support; Glucosamine
- Anti Inflamatories