TPLO stands for Tibial Plateau Levelling Osteotomy. It is a surgery for dogs that have snapped a ligament in their knee (stifle), called the cranial cruciate ligament (CCL). The CCL is a band of tough fibrous tissue within the joint. It is commonly torn in humans during sporting activities such as football. In dogs the CCL usually ruptures after it has degenerated to a weakened state and it is often a regular force acting on a diseased ligament that results in the injury.

Dogs walk on the tips of their toes and this results in the CCL being under tension during normal walking and running. The tendency is for the bottom end of the thigh bone to slide down the top of the shin bone resulting in stretching and pain in the stifle joint. TPLO surgery changes the angle of this slope eliminating this tendency. The top of the shin bone is angled forwards by making a circular cut in the bone, rotating it and applying a metal plate to hold the top section in the new position until it heals.

There are different surgeries available to treat a ruptured CCL and the most appropriate procedure will depend mainly on the weight of the dog. Age, activity level, conformation and the surgeon’s experience and preference are also important considerations, along with the owner’s finances. Alternative procedures might include TTA (tibial tuberosity advancement) or even a “lateral suture”.

TPLO surgery is the procedure of choice of many specialist orthopaedic surgeons for most cases of CCL rupture, especially for heavier dogs (over 30kg). Smaller dogs (under 15kg) can often recover with just pain relief medicine and time. Unfortunately in many cases, the recovery is often slow and incomplete and the joint is likely to develop arthritis earlier and more severely than after an effective surgical procedure. For large dogs lameness is very likely to persist permanently without an operation and can be quite severe. There is a high chance of the CCL rupturing in the other leg (about 40% within two years) resulting in severe immobility if the original leg has not been treated effectively. Without surgery dogs are likely to require lifelong anti-inflammatory medication.

The aim of a TPLO is that after the requisite recovery period, the patient will suffer no lameness and will not need exercise restrictions or long-term pain relief medicines. In 95% of patients, this is achieved with no complications. The joint will be left “dynamically stable”, which means there is no stretching during walking or running.

Complications of TPLO surgery are rare but possible. These can include bleeding and infection around the metal plate. Infections can be managed with antibiotics and the plate can be removed after the bone has healed in the majority of cases with a good long term outcome. Some dogs can go on to injure the cartilage within the joint (known as a “late meniscal injury”) which can be treated inexpensively and is not a complication of the surgery itself, but a consequence of residual instability in the stifle.

CCL rupture affects some breeds much more than others. Labradors, Rottweilers and Boxers are very over-represented whereas whippets, lurchers and greyhounds are almost never affected. However, no breed is immune and any dog can suffer a CCL injury.

At the time of writing, and as a guide, the procedure is priced at £2,800 including follow-up x-rays at 6-8 weeks after the operation.

Further reading/resources:

• Fitzpatrick Referrals
• YouTube
• Willows