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Pet Surgeons

Veterinary Surgery

Acton Veterinary Clinic does everything in our power to keep your pet healthy. If your beloved pet requires surgery, you can depend on us for exemplary care.


Torn ACL in Dogs (Cranial Cruciate Ligament Injury)

Most people have heard of a human athlete injuring their anterior cruciate ligament, or ACL, which is one of the critical stabilizing ligaments of the knee joint.

An ACL injury is also one of the most common injuries we see in dogs. With dogs, we call the knee joint the "stifle" and their "ACL" the cranial cruciate ligament (or CCL).

Partial or full tear of the cranial cruciate ligament can happen at any age and is frequently seen in middle to large breed dogs, particularly those that are overweight. This CCL injury is similar to a torn ACL in humans.

When the cranial cruciate ligament is ruptured, the dog's knee joint becomes unstable. If left untreated, chronic instability leads to the development of arthritis and, as a result, pain. A torn cranial cruciate ligament cannot be repaired without surgery.

It is best to evaluate a patient for an ACL or CCL injury after an injection of sedation and pain medication, so the dog is relaxed, and we can manipulate the joint to demonstrate a "positive drawer test" and the presence of "tibial thrust."

If these are present, a rupture of the cranial cruciate ligament can be confirmed.

Once a torn CCL has been diagnosed, the next step is to determine which surgical cranial cruciate ligament repair procedure best suits the patient's anatomy. We make a decision based on calculations from the patient's knee joint x-rays, as well as lifestyle factors (activity levels, for example).


There are three canine ACL repair options:

1. External Capsular Repair
This was the original repair technique and essentially involves placing bands of very strong suture material around the stifle to stabilize the knee joint. This can be a good option for canine ACL repairs in smaller or less active dogs.

2. Tibial Tuberosity Advancement Surgery (TTA)
This procedure involves cutting the front part of the top of the tibia (the bone between the stifle and the tarsus, or ankle joint). The fragment is rotated slightly forward and upward, then held in place with a metal plate and screws. This surgery changes the forces acting on the stifle and recruits the large, powerful quadriceps muscles to keep the tibia in its normal position during standing. The TTA procedure is considered by many veterinary orthopedic surgeons to be one of the best methods for repairing a torn ACL in dogs.

3. Tibial Plateau Leveling Osteotomy (TPLO)
This technique involves cutting the back part of the top of the tibia. The fragment is rotated slightly backward and downward, then held in place with a metal plate and screws. This surgery creates a flat surface, as opposed to a sloped surface, for the femur (thigh bone) to sit on, so it does not slip backwards on the tibia during standing.

Our Expertise in Veterinary Orthopedics

Dr. Hess has performed hundreds of successful extra-capsular repairs during his career. After being trained by one of the top veterinary orthopedic surgeons in Canada, he is proud to also offer Tibial Tuberosity Advancement Surgery (TTA) for our patients.

Dr. Hess and the team at Acton Veterinary Clinic have performed many surgeries for cranial cruciate ligament repair with the TTA procedure, all with very successful outcomes. After a diagnosis of CCL rupture, Dr. Hess will be happy to discuss your dog's individual case and recommend the procedure best suited for your dog. Our goal is to return function of the injured leg to as close to normal as possible.


The Surgeon

Dr. Stephen Hess has always had a keen interest in surgery and has performed thousands of successful procedures since graduating from the Ontario Veterinary College in 1985. In addition to performing soft tissue surgeries, Dr. Hess has received training certificates in orthopedics, including AO/ASIF Fracture Repair and TTA Cruciate Repair. He prides himself on being able to offer a wide variety of routine and specialized surgical procedures for our patients.


What To Expect

If your pet is scheduled for surgery at Acton Veterinary Clinic, we request that you and your pet arrive at the hospital between 8:30 a.m. – 9:00 a.m. In some cases, it may be more convenient for your pet to stay at the clinic overnight before the procedure. During the pandemic we will not be allowing clients into the building. Please call from the parking lot when you arrive.

The day before the procedure one of out veterinary assistants will give you a call. They will verbally complete authorization forms for the procedure, confirm contact information should we need to get in touch with you during the day, and answer any questions you may have about your pet's surgery.

Your pet will be examined by one of our veterinarians in order to identify any concerns that need to be addressed prior to administering anesthesia. If you have opted for pre-anesthetic bloodwork, the results will be reviewed by a veterinarian before the procedure.

Surgery Room

If there are any concerns, you will contacted by the veterinarian to discuss their recommendation(s). If serious concerns are identified, your pet's procedure may be postponed. Our primary goal is always to maximize your pet's safety.

A registered veterinary technician will monitor your pet during anesthesia. We provide I.V. fluids during surgery, which help keep your pet's blood pressure in the normal range and provides us with an access port to administer medications. We have state-of-the-art monitoring devices including EKG, Pulse oximetry which measures your pet's heart rate and oxygenation, and a respiratory/CO2 monitor which alerts us to any changes in their breathing pattern. We also closely monitor Blood pressure and temperature.

Injectable pain medication(s) will be administered to ensure your pet is as comfortable as possible during recovery. We use warm blankets, heating pads, and a heating lamp to help your pet's body temperature return to normal after anesthesia. If indicated, your pet will go home with oral pain medication and/or antibiotics.

Depending on the type of surgery your pet has, they may be able to go home the same day. In some cases, we recommend that they stay in the hospital overnight or for several days so that we can monitor their recovery and make sure they will be comfortable once they go home.

Laser therapy is an option after certain surgeries to help reduce pain and inflammation, speed healing, and increase circulation to the wounded area.