Tibial Plateau Leveling Osteotomy is a surgery performed on dogs to stabilize the stifle joint after ruptures of the cranial cruciate ligament (analogous to the anterior cruciate ligament [ACL] in humans, and sometimes colloquially called the same).
TTA - Tibial Tuberosity Advancement
Tibial Tuberosity Advancement (TTA) is an orthopedic procedure to repair deficient cranial cruciate ligaments in dogs. It has also been used in cats. This procedure was developed by Dr. Slobodan Tepic and Professor Pierre Montavon at the School of Veterinary Medicine, University of Zurich, in Zurich, Switzerland beginning in the late 1990s. – Wikipedia