Realignment Osteotomy
What is a realignment osteotomy?
A realignment osteotomy of the knee involves making a saw cut in the bone to allow the alignment in the bone to change. This is usually performed in the context of arthritis affecting one side of the knee where the alignment of the knee is such that more force passes through that side. Occasionally, osteotomies are performed to help with the knee's stability or offload the site of a cartilage regeneration or ligament reconstruction procedure.
What is involved in realignment osteotomy surgery?
The steps involved in realignment osteotomy surgery include:
Pre-operative planning
X-rays and CT scans are organised to determine the degree of correction required with the osteotomy. This data is analysed, and a custom-made jig is prepared for your osteotomy surgery.
Bone cuts made (osteotomy)
The custom-made jig is applied to the bone (tibia or femur). A saw is used to cut through the bone for which the osteotomy is planned.
Change in the bone alignment
Opening wedge osteotomy: This involves opening the gap where the osteotomy has been made to change the alignment (as shown in the diagram).
Closing wedge osteotomy: This involves removing a wedge of bone at the osteotomy site to change the alignment.
Fixation of the osteotomy
A metallic plate with screws is used to hold the bone in its new position. In opening wedge osteotomy, a bone graft is sometimes packed at the osteotomy site to fill the gap. This is usually performed if a significant correction is required.
What is my follow-up schedule after the operation?
Approximately 3-4 weeks of leave from work is required for a desk-based job.
2 weeks
The wound dressings will be removed, and the wound will be reviewed to ensure it has healed. The sutures will be removed at this stage. Crutches are to be used for weight-bearing until 4 weeks after the operation.
8 weeks
The range of motion in the knee will be assessed. It is expected that you will be able to fully straighten the knee and bend it more than ninety degrees. A special X-ray is taken from the hip to the ankle to confirm the alignment of your knee has been changed to a satisfactory position. Another X-ray is taken of the knee to ensure the osteotomy site is healing. Complete healing of the osteotomy is not expected at this stage.
4 months
An X-ray is performed to ensure the osteotomy site is healing. The knee should have a full range of motion but may have residual swelling around it.
8 months
A final X-ray is performed to ensure the osteotomy site has healed. Return to sports will commence 6-8 months post-operatively. At this stage, Mr Pai will discuss the benefits of removing the osteotomy plate.
Frequently Asked Questions
What are the risks of having realignment osteotomy surgery?
General complications of realignment osteotomy surgery can include:
Infection
The risk is less than 1 in 400 of developing an infection. This can occur despite using a sterile surgical technique and giving pre-operative intravenous antibiotics.
If the infection involves only the wound (superficial), it may just need treatment with a course of antibiotics.
If a deep knee joint infection occurs, it may require more surgery to wash out the knee as well as intravenous antibiotics. If the osteotomy site has healed, the plate and screws may be removed to facilitate treatment of the infection.
Bleeding
Bleeding can occur around the incision or into the knee joint itself. This is usually self-limiting but on rare occasions will require another operation to wash out the accumulated blood.
Deep vein thrombosis
Clots can occur in the deep veins of the leg that may dislodge and occlude the arteries in the lungs. DVT presents as leg pain and swelling after your operation. The diagnosis is confirmed with an ultrasound scan and, depending on the type of DVT, may require treatment with blood thinners.
Specific complications of realignment osteotomy surgery can include:
Metalware irritation
The metal plates inserted to hold the osteotomy can sometimes irritate the overlying skin. If this occurs and is bothersome, the plate can be removed once the osteotomy heals. This is not usually performed for at least one year after the osteotomy.
Non-union
Healing of the bone at the osteotomy site can take as long as 3-6 months. Sometimes healing does not occur, and patients experience ongoing pain. In this situation, a revision procedure may need to be performed to roughen the surfaces of the osteotomy and insert a bone graft to stimulate healing.
Disease progression
An osteotomy is usually performed in the context of arthritis affecting one side of the knee to redirect the load of the body away from this side. Sometimes, the arthritis can progress to involve other parts of the knee and can cause a recurrence of knee pain. In certain cases, this may require a revision procedure to a total knee replacement.
Fracture
An osteotomy involves weakening the integrity of the bone so that the alignment can be changed. Sometimes the weakness can cause a fracture of the bone, which can spread to involve the knee joint. This situation is usually identified during the operation, and the fracture may require stabilization with a staple or plate and screws.
Damage to the popliteal artery or vein
This is a rare complication that can occur when the osteotomy is being performed. The popliteal artery passes behind the knee joint. During the osteotomy, retractors are used to protect the artery from damage. In rare cases, whilst the osteotomy is being performed the saw blade can injure the artery or vein, causing profuse bleeding. This will require a repair or bypass surgery performed by a vascular surgeon.
Damage to the common peroneal nerve
This is a rare complication that can occur when the osteotomy is being performed. The common peroneal nerve wraps around the fibula close to the knee joint. Rarely, whilst the osteotomy is being performed the saw blade can injure the nerve. Sometimes, if a major change in alignment is being made, the tethered common peroneal nerve is stretched. In either case, the result is a foot drop. If this occurs, it may require surgery to explore and decompress or repair the nerve.
Stiffness
The knee can become stiff after surgery due to the formation of scar tissue. This stiffness usually resolves with physiotherapy but can sometimes persist. If the knee is not bending or straightening adequately 6-8 weeks post-operatively, a manipulation procedure may be required. This involves putting the patient to sleep and pushing on the knee in order to break the scar tissue.
Does a realignment osteotomy surgery cure my arthritis? +
An osteotomy is designed to redirect the weight of the body away from the part of the knee with arthritis. It does not however, cure the arthritis or cause the cartilage to regenerate. In a carefully selected patient, an osteotomy will significantly relieve the pain from arthritis. This effect can last for several years following the surgery.
Are there limitations on my activity an osteotomy? +
Once you have recovered from your osteotomy there will be no restrictions on your activities. The osteotomy is designed to allow you to remain as active as possible.
Do I need to wear a brace on return to activity? +
No, a brace is not required for activity after an osteotomy has healed.
How long will I use these crutches and brace post-operatively? +
Crutches tend to be used for 4 weeks after an osteotomy is performed. They are designed to offload some force away from the osteotomy site in order to make your rehabilitation in the early stages more comfortable.
Will I need my osteotomy plate removed? +
Having your plate removed is not a neccesity but is recommended.
The plates used to hold the osteotomy are rigid and thick as they are designed to withstand the force of your body weight. Sometimes the plate can be prominent and people can feel the plate under their incision. In these situations, removal of the plate can help with these symptoms.
In the future, you may need more surgery to your knee such as a knee replacement. The presence of a plate can make this more difficult. Removing a plate several years after surgery can be more challenging as there may be bony ingrowth and overgrowth.
Plate removal is usually performed 9-12 months after your initial surgery once the osteotomy site has completely healed and is a day case.
Will my leg look different after osteotomy surgery? +
Performing an osteotomy will change the alignment at the knee joint and therefore the appearance of the affected limb. The operated knee will look straighter after the operation.
Will an osteotomy make a knee replacement in the future more difficult? +
There are certain technical considerations that need to be taken into account such as removal of the plate and the scarring in the knee caused by the osteotomy. However, a knee replacement performed after having an osteotomy does not perform differently compared to patients that have just had a knee replacement.
What are the long term results of a high tibial osteotomy? +
For patients with osteoarthritis, a tibial osteotomy will last for at least 10 years and prolong the need for a knee replacement in 8 out of 10 patients.
When can I drive after realignment osteotomy surgery? +
You will not be able to drive for 6 weeks following an osteotomy. You must be off strong painkillers, be walking without crutches and have a relatively painfree range of motion in the affected knee before your commence driving.
When can I swim after realignment osteotomy surgery? +
The wound should be kept dry for two weeks following the operation. Once the wound healing is reviewed at your 2-week post-operative consultation you will be able to shower with no wound dressings on. Participating in pool based rehabilitation or swimming is not recommended for 4 weeks after your operation as it may increase the risk of infection.