Buck Creek Veterinary Clinic, P.C.

10972 North State Rd. 3
Knightstown, IN 46148





A tear of the Anterior (Cranial) Cruciate Ligament is the most common knee injury in dogs. In most cases, the dog will present with a sudden reluctance to bear weight on a rear leg. Over the course of a week or two, the owner may notice an improvement. However, the knee will be swollen and arthritis will begin to build up. An ACL tear almost always leads to osteoarthritis and continued problems for the dog.



After reviewing the pet's history, the veterinarian will try to get the dog to exhibit a "drawer sign". This is done by stabilizing the femur while maneuvering the tibia. If the tibia slides forward while being manipulated, the dog has a ruptured ACL. In some cases it may be necessary for the dog to be sedated to check for the "drawer sign" since a trip to the veterinarian makes some dogs nervous and tense.


Tearing an ACL

A torn ACL in dogs is similar to a torn ACL in people. Many times it occurs with a wrong step by an excited pet, a quick turn in the yard while playing, or rough play. In an older, large breed dog that is overweight, it can occur by jumping off the couch or bed. Being middle aged and overweight are predisposing conditions that make an ACL tear more likely. Once a dog has ruptured an ACL, they are at greater risk for rupturing the ACL in the opposite leg than dogs with no previous tear.



Repairing a torn ACL is a surgical procedure. Just like our other surgeries, preanesthetic bloodwork is recommended (required in older pets). Also, a radiograph showing the dog's knees and pelvic area is required prior to surgery. This allows the doctor to see the amount of arthritis in the hip joints and the knees and to make sure there is not any other damage in the knee joint.


There are a few different surgical procedures to repair a torn ACL. Dr. Caldwell performs what is known as an extracapsular repair. In this surgery, the strands of torn ligament are removed completely and a large, strong suture is inserted to replace the ligament. The suture is anchored by passing it around the fabella behind the knee and through a hole drilled in the front of the tibia. This stabilizes the joint and prevents the "drawer sign."


Post-Surgical Care

Ultimately the success of the ACL repair lies with the owner and the at home care they provide. When your pet is discharged, we will review the instructions for at home recovery with you and answer any questions you may have. Standard post operation instructions include:

  • First Week Post Op: The operated leg will be tender and most pets will avoid using it. Some pets appreciate ice packs wrapped in a towel placed over the incision area 2-3 times a day for 10 minutes at a time. This can be helpful for those who tolerate it.

  • Physical Therapy: Gentle, passive movement of the operated leg will reduce stiffness, keep the joint mobile, and speed the healing process. Gently flex and extend the leg and gradually work up to bicycle like movements, as your pet tolerates it. You can push gently against your pet's foot and let them push back. Aim for 3-4 sessions per day of 5 minutes per session.

  • Exercise Guidelines: Slow leash walking only for the first week, gradually increasing time and distance as your pet tolerates it comfortably. He or she will gradually start touching their toes to the ground and start bearing weight on the leg. Absolutely NO running, jumping, playing with other animals or off leash exercise for the first 6 weeks. Swimming is a wonderful form of physical therapy for pets who like it. No swimming until the incision is healed completely, usually about 10 days.

  • If there are other pets in the home, we may suggest cage rest and only supervised play.

  • Your pet will also receive pain medication to aid their recovery