HIGH TIBIAL OSTEOTOMY (HTO)
A Tibial Osteotomy is an operation in which your tibia (shinbone) is surgically broken (this means that it is broken under the control of a surgeon), and realigned into a better position. The purpose of this is to alter the way that forces cross the knee and takes pressures off certain areas of the joint surface.
Once healed, the body weight is transmitted mainly through undamaged cartilage resulting in less pain and swelling for the patient. This operation is sometimes carried out when knee arthritis is present in young and middle-aged patients. It is only effective if the arthritis is confined to ONE area of the knee, the rest of the joint must be healthy.
An osteotomy is usually only considered as a treatment option if things such as Physiotherapy and Anti-Inflammatory medication has not helped with the patients symptoms.
A high tibial osteotomy (HTO) is usually performed when there is localised medial compartment osteoarthritis of the knee and mal-alignment (this is where the medial or lateral side of the knee is loaded excessively). Sometimes it can be a difficult choice whether to perform a HTO or a medial Unicompartmental knee replacement (UKR). HTO is a better option for younger patients (under 50 years of age) and those who are very active (particularly if you have a heavy manual profession).
The decision for HTO is made following a detailed discussion with your surgeon.
Mal-alignment is seen on the right image. In a normal knee, a line drawn from the centre of the hip to the centre of the knee will go through the middle of the knee joint (left hand image). In mal-alignment, (right) the line goes through one side of the knee joint (medial in this case) indicating that side of the knee is being loaded excessively. The principle of a HTO is to shift the load to the other side of the knee.
THE PROCEDURE
An osteotomy is carried out under General Anaesthetic. An incision of approximately 15cm is made over the upper part of the tibia. Using X-ray images as guidance, the bone is then cut ALMOST all the way across. This cut allows the surgeon to re-align the tibia. The bone is then held in its new place with a plate and screws
Pre and post-op images showing medial osteoarthritis (on the left hand picture) and the correction Held with plates and screws (on the right hand side).
Measurements are taken to decide how much to re-align the leg, the bones are then held with plates and screws
THE RECOVERY
Normally you will go home 2 days after this operation. To begin with, you can partially weight bear on the leg, you will be allowed to progress to full weight bearing after 6 weeks as long as your X-Ray shows that the bone is healing. Once fully weight bearing you can stop using your crutches as soon as you have no discomfort. Total recovery is expected to take around 3 months. Looking at long-term prognosis, 90% of patients have a good outcome at 5 years and 70-80% have a good outcome at 10 years.
