Sometimes also, due to the abnormal motion at the
knee after the ACL tears, the meniscus (cartilage cushion) in the
knee is also damaged. This may also need partial debridement at surgery. These manipulations are at least as important as the method of stabilization.
TPLO is "tibial plateau leveling osteotomy" and involves cutting the bone itself, changing the angles that the bones relate to each other in the knee and creating stability that way.