TPLO:  The tibial plateau leveling osteotomy surgery has been around for about 20 years.  The idea behind it is to change the angle of the tibia so that the femur above it no longer slips backwards.  The ACL is suppose to prevent this from happening but when it tears, the femur tends to slip backwards from the tibia and this causes pain and inflammation.  This surgery has a very high success rate.  The downside is cost.  At our clinic, the total cost tends to be $3200-$4200.

 

TTA:  The tibial tuberosity advancement has been around for over 10 years.  The idea behind this surgery is to move the patellar tendon forward so that the forces acting on the knee cancel out - the backwards slope of the tibia pushing the femur backwards is counteracted by the patellar tendon pulling the femur forwards.  The tendon is moved forward by cutting the place it connects to on the tibia and pushing it forward.  The cut is made in a non-weight bearing area of the bone, and so the recovery tends to be faster and less painful.  There is currently a controversy among sugeons as to which surgery (TPLO or TTA) is better.  The overall cost of the TTA is $3000.


IsoLock CrCL:  Another variant of this surgery is known as the tightrope technique.  This technique has been around for about 5 years.  The idea behind this surgery is to recreate the torn ligament with an artificial one.  The material used is high-strength and is used extensively in human surgeries.  It is resistant to stretching or breaking.  The artificial ligament is passed from the femur to the tibia in a location that is isometric - meaning that it is under equal stress when the leg is flexed or extended.  The reported complication rates and clinical outcomes are similar to the TPLO surgery.  The benefit to this surgery is that no bones are cut, so the procedure is less invasive or painful.  Also, it tends to be less expensive.  The overall cost at our clinic is $2000. 


Extracapsular Technique:  Other words for this include lateral fabellar suture, lateral suture stabilization, and "fishing-line technique".  This surgery has been around for about 50 years.  This tends to be one of the more common ways to repair an ACL tear because many general practitioners feel comfortable performing it and it tends to be less expensive overall.  However, recent studies have found that while the surgery does lead to better outcomes than doing nothing, it is inferior to the other surgeries listed here.  This is for a few reasons:  1)  The implanted wire runs around soft tissues that break down over a few weeks to months, causing the implant to become loose, 2) The nylon used tends to stretch over just a few days, and forever becomes loose and in-effective, 3) The positions on the knee where the wire is placed have different degrees of stress acting on it depending on flexion or extension of the knee - which is not ideal.  This surgery is best only performed in dogs under 40 lbs, as the nylon is more likely to break in larger animals.