Anterior Cruciate Ligament (ACL)


Anterior Cruciate Ligament Injury

One of the more common orthopedic conditions we diagnose in dogs is injury of the cruciate ligament in the knee (stifle), which is analogous to the ACL ligament in humans. This is often a degenerative process, but can be due to an acute injury as well. A ligament is a soft tissue structure that connects bones to bones and is like a rope made up of many fibers. Sometimes an ACL injury can be “partial” meaning only part of the ligament was injured, or the injury can be a “complete rupture/ tear”. Dogs with ACL injury, especially if it is a complete tear, usually need surgical repair for the most stable long term result. Any injury to the cruciate ligament will spur on the formation of arthritis. Surgical repair of the knee is recommended because it helps reduce the magnitude of arthritis formation by stabilizing the joint, and preserves the best range of motion and long-term use of the joint. However, some dogs are not good surgical candidates, and/or sometimes surgery may not be an option due to financial constraints. In these cases, or when cruciate disease is initially suspected but not entirely confirmed, we often try treatment with conservative medical care, which includes the below:


1) Medications

-Rimadyl:  a non-steroidal anti-inflammatory medication (NSAID) to reduce inflammation and pain

-Gabapentin: a pain medication that has shown to be very effective for most dogs

-Glucosamine type joint supplement (Phycox, Cosequin, etc)



2) Strict rest: Strict rest is very important for at least the next 30 days. Leash walk only, on short walks to use the bathroom. Do not allow any running, jumping, playing, or access to furniture. When your pet cannot be directly observed, he/she should be confined to a small room or crate. 


3) Icing and Passive Range of Motion: Ice the knee 10-15 minutes twice a day for 2 weeks. After two weeks you may discontinue the icing and began passive range of motion, repeat 5 times twice a day. (Passive range of motion is having your pet lay down with the affected hind leg on top, and helping pull the leg through a full range of motion (like a bicycling motion) slowly, with stretching in each direction, to help keep the joint and muscles moving).


4) Once conservative therapy is initiated, your veterinarian will tell you when to bring your pet back for a follow up examination (often 2-4 weeks after the initial diagnosis).


5) Weight loss/keep lean: It is very important to keep your pet at a lean weight. In fact, obesity is one of the most important factors in cruciate injuries and other orthopedic disease such as arthritis formation. Pets who are being activity restricted will need to have their food intake reduced, since they are not burning calories. You may add in green beans to the diet while decreasing amount of food your pet is fed to prevent weight gain, especially while exercise is being restricted (this also helps with general weight loss, as green beans have a lot of fiber but minimal calories, to help your pet feel more full while their overall calorie intake is being reduced). If your pet is already overweight, please discuss with us to develop a weight loss plan for your pet.


6) Surgical options for cruciate injury: When surgery for cruciate injury is pursued or deemed necessary for your pet, we will refer you to one of the local specialty hospitals in the Triangle area, all of which have fantastic board-certified surgeons who are highly skilled in orthopedic surgery. The most common, and highly successful, surgical technique is called the TPLO procedure. When performed by a Board Certified Veterinary Surgeon this procedure is incredibly beneficial and often times returns the dog to full function. At this time we do not recommend having a “Lateral Tie” procedure performed as the complication rate is quite high.

Arthritis is a common secondary issue when a dog has an ACL injury. Please read our article on arthritis as many of the recommendations will apply to dogs with ACL injury: