What is a Tibial Plateau Leveling Osteotomy (TPLO)?
A Tibial Plateau Leveling Osteotomy (TPLO) is a surgery performed to repair a cranial cruciate ligament (CCL) rupture in dogs. Cranial cruciate ligament ruptures are one of the most common injuries in the dog and the major cause of degenerative joint disease (DJD) in the stifle joint. The CCL is one of the most important stabilizers inside the canine knee, it connects the femur and tibia together so that the knee works as a stable, hinged joint.
The two most common causes of CCL ruptures are trauma and degeneration of the ligaments within the joint. Acute or traumatic cruciate rupture is caused by a twisting injury to the knee joint; this twisting occurs most often when the dog is running and suddenly changes direction. A cruciate ligament rupture is usually extremely painful and the knee joint becomes unstable, resulting in lameness.
A more chronic form of cruciate damage occurs due to progressive weakening of the ligaments due to repeated trauma or arthritic disease. Initially, the ligament becomes stretched or partially torn and lameness may be only slight and intermittent. With continued use of the joint, the condition gradually gets worse until a complete rupture occurs.
Diagnosis
- Radiographs
- Clinical symptoms; toe touching, lameness, limping, etc.
- Demonstration of cranial drawer motion using direct and indirect palpation techniques
Surgical Technique
TPLO surgery involves changing the angle of the tibia (the bone below the stifle) so that the cranial cruciate ligament is no longer needed.
Each patient’s tibial plateau angle and the rotation needed to achieve an end point of 5 to 6.5 degrees are calculated preoperatively using radiographs. We use pre-surgical planning for every TPLO to ensure consistency intra-operatively.
An arthrotomy is performed and the ligaments are checked, the ruptured cranial cruciate ligament is debrided and the meniscus ligament is checked.
A curved osteotomy is performed using a biradial saw blade and the proximal tibia is rotated to the proper degree angle and stabilized with a TPLO bone plate.
The photo with the R shows a TPLO post-op radiograph with the plate and screws visible
The photo with the L shows the tibia after having the curved osteotomy done with the plate in place
Recovery
- Activity levels are restricted to short, slow leash walks only for several weeks
- Recheck appointments are in place to check before slowly increasing activity levels
- 8 week post-op radiographs are done to confirm bone healing