Knee Surgery

              Cranial Cruciate ligament rupture and Patellar luxation

Tearing of the cranial cruciate ligament (CrCL) and patellar luxation (medial or lateral patellar luxation) are the most common conditions of hind limb lameness in dogs and cats.

What is this cranial cruciate ligament?

Cranial cruciate ligament in dogs (ACL-anterior cruciate ligament in humans) is a ligamentous structure which connects the back of the femur bone (thigh bone) to the front of the bone below it which is called tibia. In simple language, this ligament prevents unnecessary movement of tibia by stabilizing the knee joint. 

Cranial cruciate injury: This injury in dogs and cats can result from traumatic injury but may develop without trauma as well, due to a degenerative process. Once the ligament is torn, the dog will become pronouncedly lame on the affected limb and may not even be able to bear weight. Cranial cruciate ligament injuries usually do not fully recover without surgical stabilization because the ligament is unable to heal once torn. Moreover if not repaired soon enough it can lead to similar lameness in other limb as well. At Mercer Street Veterinary Hospital, we recommend surgical repair as soon as the condition is diagnosed to avoid further damage to the knee joint and lameness in other hind limb.

Patellar luxation: The patella, or knee cap, can sometimes become loose and displaced in dogs and cats, a condition we refer to as patellar luxation. The displacement is mostly medial in small dogs and cats; lateral in large dogs. Patella serves to act as a pulley in redirecting and conducting the forces of the large quadriceps muscles of the thigh to extend the knee. If the patella is displaced, the animal can have difficulty using the knee appropriately and be painful. Diagnosis of this condition is made during the orthopedic examination and the completion of X-rays. A variety of surgical techniques can be employed to successfully correct this condition safely depending on the type and severity of the luxation.

Our Mercer Street Veterinary Hospital Kirkland Veterinarians are trained in various different techniques required to repair both of these common conditions successfully in both dogs and cats.

Please spend some time reading the sub-categories on this page for different surgical techniques for both of these conditions.

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