What is ACL Tear in Dogs?
What is it?
How is it Treated?
Breed Predispositions
Labrador Retrievers Golden Retrievers Rottweilers Newfoundlands Akitas Boxers American Staffordshire Terriers St. Bernards Chesapeake Bay Retrievers Mastiffs
Introduction
For years, Alex and his loyal Rottweiler, Titan, had enjoyed many adventures together, exploring new trails and parks every weekend. One afternoon, while playing an energetic game of frisbee, Titan suddenly yelped in pain and began limping, unable to put weight on his hind leg. Worried about his beloved companion, Alex quickly realized that Titan needed professional care and took him to the veterinarian. After a careful examination, the vet diagnosed Titan with an ACL tear, a common but painful injury in dogs. In this blog post, we will discuss what an ACL tear is, its causes, symptoms, and treatment options, as well as how to prevent this injury. By understanding this condition, you’ll be better prepared to support your canine friend’s recovery and help them return to a healthy, active lifestyle.
Anterior Cruciate Ligament (ACL) and Cranial Cruciate Ligament (CCL) tears are injuries to the ligaments that stabilize your canine’s knee joint. The torn ACL in dogs attaches to the front of the knee joint, which connects to the tibia bone. At the same time, CCL fastens at the back of the knee joint, near the top of the tibia bone.
ACL and CCL tears occur when excessive stress is put on the knee joint from running, jumping, twisting, etc. It occurs most commonly at the point where the two sides of the knee connect. This is called the “knee” area. ACL tear in dogs are injuries common in dogs. They occur most often in older and larger dogs, especially those overweight.
There are two types of ACL rupture: acute and chronic.
- Acute complete Tear in Dogs (AATD)
This is a condition where there is eye inflammation due to injury from foreign bodies such as sand, dirt, grass seeds, etc., which causes pain and swelling and can heal without surgery.
- Chronic ACL Tears
These injuries occur when the knee joint’s anterior cruciate ligament tear (ACL) is torn. Dogs with chronic tears often result in arthritis and osteoarthritis. The ACL connects the femur to the tibia and prevents excessive knee movement. It helps your dog stabilize the knee during physical activity such as jumping, running, climbing stairs, and squatting.
What Causes Canine Cranial Cruciate Ligament Tears?
ACL rupture is common in active dogs. This happens when a dog moves its leg quickly, such as running, jumping, or playing fetch. This sudden movement causes the knee joint to bend sharply backward, causing cruciate ligament rupture.
This traumatic injury usually occurs in two ways: the dog lands awkwardly on the front of the tibia, jumps off a curb or steps down onto a driveway.
An injured leg caused by these accidents is called a traumatic tear. A traumatic or partial tear may cause pain, swelling, bruising, and limping.
Complete tears caused by excessive exercise are known as degenerative tears. Degenerative tears are less painful but still cause damage to the knee and may cause joint disease.

Degenerative ruptures are usually seen in middle-aged or older dogs. They tend to develop slowly over the years and are often associated with arthritis.
Symptoms of ACL Tear in Dogs
A dog with a torn ACL may experience the following:
- limping
- lameness
- stiffness
- pain
- swelling
- loss of normal function
These symptoms usually appear within 24 hours after injury in dogs.
How do Veterinarians Diagnose ACL Injury in Dogs?
To diagnose dogs with ACL or CCL rupture, veterinarians use x-rays, ultrasound imaging, arthroscopic surgery, physical examination, and surgery. In addition, an MRI scan is often used to confirm the diagnosis.
Physical Examination
Your dog needs a thorough physical exam to determine whether he has torn his ACL. The vet should be able to tell you this based on your dog’s symptoms and behavior.
If your dog shows signs of pain when walking, limping, or jumping, he may have a torn CCL. Your veterinarian can perform a simple test called the tibial thrust test. This involves gently pushing down on your dog’s knee joint. Likewise, if your dog yelps or cries in pain, he likely has a ruptured ACL.
X-rays
An X-ray is a diagnostic tool to detect bone fractures, tumors, and other abnormalities. An X-ray uses radiation to internal image structures inside the body.
When diagnosing canine ACL tears, vets use an X-ray machine called a radiograph. Then, the dog lies on a table, and the veterinarian takes pictures of its knee joint. This helps determine whether there is damage to the ligament (ACL) and if surgery is needed.
Ultrasound Imaging
Ultrasounds are great tools for diagnosing canine injuries. They’re noninvasive, painless, and relatively inexpensive. In addition, ultrasounds allow vets to view internal structures and organs in real-time.
Orthopedic Surgery
An orthopedist will determine if your dog needs surgery to stabilize the knee. For severe cases, vets recommend surgical intervention. Surgery involves cutting open the skin over the knee and removing damaged tissue. Graft replacement involves replacing the torn ACL with a synthetic material. Afterward, the surgeon stitches the wound closed. It has been reported that 85% of all orthopedic injuries in dogs are some form of ACL injury.
After the surgery, most dogs recover quickly and resume regular activity within two weeks. However, some dogs experience stiffness, swelling, bruising, and soreness at the incision site. These symptoms typically resolve within one week. Dogs who undergo arthroscopy should be monitored closely for signs of infection.
Treatment Options for Dog ACL Tears
The best treatments for ACL tears in dogs include rest, physical therapy, anti-inflammatory medications, and surgery. Surgery for dogs is typically recommended for severe cases.

- Physical Therapy (PT) focuses on healthcare services that help people and animals recover from illness or injury through exercise, manual manipulation, and movement. In addition, PTs work closely with patients to develop and implement treatment plans that address their specific goals and needs.
- Anti-Inflammatory Medications (AIMs) treat inflammation and pain caused by ACL, arthritis, gout, bursitis, tendonitis, carpal tunnel syndrome, rheumatoid arthritis, osteoarthritis, lupus, psoriasis, and many others. They reduce swelling and relieve pain.
- Surgery is performed to repair dog tears. Several dog ACL surgery procedures are available, including arthroscopic surgery, open surgery, and graft replacement.
- Arthroscopy is a type of surgery involving tiny instruments to view the inside of the joint. Arthroscopic surgery allows veterinarians to see the damaged area and remove any debris.
- TPLO surgery (Tibial plateau leveling osteotomy) is a surgical treatment option for treating ACL injuries in dogs. TPLO surgery aims to realign the tibia and femur bones and stabilize the knee joint. This allows the dog to walk normally again after the injury.
To perform this operation, a veterinarian makes a small incision over the injured area and removes bone fragments that may be causing pain. Then he uses a unique tool to cut through the ligament and reattach the two bones.
This simple procedure takes only a couple of hours to complete. However, there are some risks associated with TPLO surgery. One risk is infection. Another is that the dog may not heal properly and develop arthritis later in life.
For partially torn ACL, owners can treat the injured area themselves. After surgery, you should expect your dog to recover from a torn ACL after several weeks. Owners should expect their pets to limp for a few days following surgery. During this time, they should avoid strenuous activity and exercise.
Prevention Tips for CCL Injuries in Dogs
You can do several things to prevent CCL or “cranial cruciate ligament tears in dogs.
- Make sure your dog has plenty of exercises. Exercise helps strengthen muscles and bones and reduces stress levels.
- Make sure your dog wears proper footwear. Shoes should fit properly and provide support for the foot. If your dog is overweight, it may benefit from wearing a boot or wrap to protect the injured area. Many dogs today are clinically overweight. Unfortunately, they’re usually not just fat but also obese.
- Ensure your dog doesn’t jump too far or run too fast. Finally, make sure your dog walks on a leash whenever possible.
- Don’t let your dog play rough games like tug-of-war. These games can lead to torn ACLs.
Frequently Asked Questions
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