Many people are familiar with an anterior cruciate ligament injury from what happened
to various football players(Adrian Ross, Mike Seidman, Kevin Curtis , Damian LaVergne, etc).
Similar injury happens in dogs and cats, typically from the same cause of over stressing
the knee during playful exercise, such as sudden jumps from high places, or landing
on the leg wrong. Except in few dogs where it may show as a slow, ongoing lameness
of a rear leg, in most dogs it is characterized by sudden onset of lameness.
The lameness happens from rupture of the anterior cruciate ligament causing
instability, inflammation, arthritis and pain of the knee joint. This instability
will sometimes cause a tearing of the
meniscus
causing additional pain and lameness.
Treatments
Several methods including self grafted ligament placement or installing sutures to act
as a replacement ligament are used. TPLO surgery is a technique that is being used to stabilize
the joint and get the maximum stability with least joint intervention. TPLO appears
to have several benefits over other treatments that are being performed.
TPLO
Dr. Slocum, the developer of the TPLO technique, used an approach different than repairing the injury.
After analyzing the forces of the knee, he realized that restructuring of the joint
could prove more beneficial. The natural shape of the knee is such that when weight
is placed on it, shear forces and the slope of the angle causes the joint bones to slip.
Normally, the ACL ligament counters these forces. The TPLO surgery is an operation in
which the tibia is cut and the knee joint rotated so that the slope is leveled,
thus negating the need for the ACL.
Normal slope of knee
Post-op slope of knee negated the need for the ligament
Benefits
On short term basis, results of repairing or replacing the ligament are comparable
to the results of the TPLO surgery. However, those methods still permit
future joint instability from additional injuries. The main goal of the TPLO is
to re-align the knee joint so that the torn ligament is no longer needed -
thus the possibility of future injury is greatly lessened.
