High Tibial Osteotomy
What is a High Tibial Osteotomy
A high tibial osteotomy seems like a medical tongue twister, intentionally complicated to confuse the average person. In fact, the title is a descriptive one, detailing the operation itself. In medical jargon, the suffix 'otomy' means 'to cut or incise' and 'osteo' refers to bone. An osteotomy is therefore the cutting of a bone. The location of the cut is also stated as the tibia is the shin bone in the lower leg.
Osteotomy is a surgical procedure designed to change the alignment of a specific bone. Osteotomies are performed all throughout the body, one of the more common being the operation that corrects severe bunions in feet.
Osteotomies can be used to correct unwanted angulation or rotation of the bone. In osteoarthritis, it is the angle that is important and the angle that needs correcting.
Indications for High Tibial Osteotomy
A High Tibial Osteotomy is used to treat unicompartmental osteoarthritis of the knee. Unicompartmental means the arthritis only affects one part of the knee. In this case, either the inside half, or outside half of the knee.
Once the smooth cartilage lining of the joint starts to wear away, the angle at the knee joint can begin to change. If the inside of the knee is being worn (the most common occurrence) the result is becoming "bow-legged". If the outside of the knee is being worn, the knee becomes "knock-kneed".
This slight change in angulation results in all of the body's weight being taken through the affected side. This results in dramatically increased wear on the already worn side, but good preservation of the unaffected side.
A High Tibial Osteotomy aims to realign the bones to restore even weight bearing between the inside and outside of the knee. It does not make the affected side "unworn", it just stops it from taking the overwhelming majority of the weight.
High Tibial Osteotomy - What is Involved?
There are two ways to perform a high tibial osteotomy, an opening wedge or a closing wedge.
An opening wedge cuts the bone, increases the angle and fixes it in its new position filling the gap with a bone graft.
A closing wedge osteotomy removes a wedge of bone to achieve the change of angle.
Either way an osteotomy is a major operation, effectively fracturing the main weight bearing bone of the lower leg and surgically fixing it afterwards.
The rehabilitation is lengthy and involves a prolonged period avoiding all weight bearing through the leg. Pain, stiffness and swelling are all experienced after the operation.
Having this surgery (for most people) requires a significant period off work and a major disruption to lifestyle. Mobility will be limited for 6 weeks and it will take 3 - 6 months to resume full activity.
Why Have A High Tibial Osteotomy?
A high tibial osteotomy is a time saving operation. It is generally performed on people too young to have a total knee replacement. Knee replacements wear out quickly when placed in young people so the osteotomy is performed to try and provide increased function and relieve pain until the person is old enough to have a total joint replacement.
It is important to note that an osteotomy does not address the wear on the affected side. It decreases the load on that half of the knee but it will remain worn and therefore cause some pain. This makes it somewhat different to a knee replacement that directly aims to relieve pain.
Should I Have A High Tibial Osteotomy?
This is a question that has many variables. The decision can only be made by you after discussing your particular medical history with an orthopedic surgeon who specializes in high tibial osteotomies.
Good candidates have a tolerance of pain, are active, not overweight and have a good understanding of why the procedure is being performed and therefore have appropriate expectations.
This operation is not for everyone but for many people it will let them delay a total knee replacement for many valuable years.