A Dog's Cranial Cruciate Ligament
Your anterior cruciate ligament - or ACL as it is commonly known - is a thin connective tissue that helps to stabilize the human knee.
Dogs don't actually have an ACL but they do have a very similar ligament called the cranial cruciate ligament (CCL or sometimes CrCL) that connects your dog's shin bone to their thigh bone. This connective ligament performs the critical function of stabilizing your pup's knee.
There are a few similarities between your ACL and your dog's CCL but they actually work a little differently. The primary difference between a person's ACL and your pup's CCL is that for dogs, unlike people, this ligament is always load-bearing. This is because your pet's knee always remains bent while they are standing.
For the sake of this post, we will refer to your dog's cranial cruciate ligament as their ACL.
How ACL Injuries in People & CCL Injuries in Dogs Differ
ACL injuries in people are most common in athletes. These injuries tend to occur due to an acute trauma stemming from a sudden movement such as a jump or change of direction (think of basketball players in action). In dogs, CCL injuries tend to develop gradually, becoming progressively worse with activity until a very painful tear occurs.
Because the cranial cruciate ligament is so commonly called an ACL, from this point on I will refer to your dog's CCL as their ACL.
Signs of ACL Injury in Dogs
There are a number of symptoms that are commonly seen in dogs with ACL injuries, including:
- Stiffness (particularly after rest, following exercise).
- Difficulty rising off floor.
- Struggling to jump up on furniture or climb stairs.
- Hind leg lameness and limping.
Continued activity on a mildly injured leg will cause the injury to worsen and symptoms to become more pronounced.
Treatment Options for Injuries to ACL in Dogs
Our vets are often asked 'Can a dog live with a torn ACL?'. The truth is that these injuries are extremely painful for dogs. If your dog has a single ACL injury they will typically begin to favor their non-injured leg during activity. This in turn often leads to a torn ACL in both of the dog's legs, severely limiting their mobility and quality of life.
It is estimated that about 60% of dogs with a single ACL injury go on to injure the other knee soon afterward.
There are a number of treatment options available for dogs suffering from ACL injuries, although, in most cases surgery is the best and most effective option. When determining the right treatment for your dog, your vet will consider your dog's age, size, weight, lifestyle and energy level.
Treating a CCL injury with a knee brace is a non-surgical option that may help to stabilize the knee joint in some dogs. The support provided by a knee brace gives the ligament time to scar over and repair itself. Treating CCL injuries through the use a knee brace may be successful in some dogs when combined with restricted activity.
Extracapsular Repair - Lateral Suture
This surgery involves replacing the torn cruciate ligament with an artificial ligament on the outside of the joint. This ACL surgery for dogs is typically recommended for small to medium sized breeds weighing less than 50lbs.
Tibial Plateau Leveling Osteotomy - TPLO
TPLO is a popular and very successful surgery that works to eliminate the need for the cranial cruciate ligament (CCL) by cutting and flattening the tibial plateau, then stabilizing it in a new position with a plate and screws.
Tibial Tuberosity Advancement - TTA
TTA surgery also eliminates the need for the CCL ligament by cutting the top of the tibia, moving it forward, and then stabilizing it in its new position with a stainless steel metal plate.
Recovery from ACL Surgery
The fact of the matter is that no matter which treatment you and your vet choose, your dog's recover from their ACL injury is going to be a slow process. Expect your dog to require 16 weeks or longer to completely heal from surgery and return to normal function. A year after surgery your dog will be running and jumping like their old self again.
To help your dog recover as quickly as possible from an ACL injury be sure to follow your vet's advice and never force your dog to do exercises if they resist. To avoid re-injury be sure to follow your vet's instructions closely and attend regular follow-up appointments so that your veterinarian can monitor your pet's recovery.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.