When you stand, your weight travels in a straight line from the centre of your hip joint to the centre of the ankle joint. If one of the leg bones is bowed or deformed, this “weight bearing line” may not cross through the middle of the knee joint and put abnormal ressure on one side of the knee joint. This is most common in people with osteoarthritis which has worn out part of the knee joint, but can also happen after a fracture.

The inner or medial knee is the most common part to be worn out, leading to a more bow-legged appearance (varus). The surgery used to fix this is a high tibial osteotomy (HTO).

If the outer (lateral) compartment is worn instead, it can create a more knock-kneed appearance (valgus). The surgery used to fix this is a distal femoral osteotomy (DFO).

You are most likely to benefit from realignment surgery if you are:

• Younger (40-55 years old)
• Working in a physical job
• Too young or too active for a knee replacement surgery
• Not too stiff in the knee
• Not overweight (BMI less than 35)

The surgery corrects the weight-bearing line so your body weight passes through the middle of the knee when standing or walking. It aims to give you pain relief, especially for weight-bearing or impact activities (such as running).

If you’re considering osteotomy surgery, it’s likely that you have been in pain for a long time. This can lead to hip and thigh muscle weakness which causes functional loss. You might have put on weight, not be able to walk as far, need a buggy for the golf course, or find stairs tricky.

Your recovery will be easier and quicker if we can reverse some of these changes. At MTP Health we have dedicated ‘prehab’ programs that involve assessing exactly what has been weakened and using individualised therapies to target your specific needs and prepare you for surgery and beyond.

You will need time off work and driving afterwards, so it’s important to consider the timing of surgery. It might affect:

• Family events and holidays
• Work trips or busy periods

It’s important to ensure that the skin on your painful leg remains free from scratches. Scratches are an infection risk and can delay surgery. To prevent them, avoid leg shaving in the week before and don’t do any last-minute gardening.

As part of planning the surgery, you should have had alignment imaging either in an EOS or a CT scanner. Your surgeon will have all these on their computer.

Depending on your other medical conditions, you may need to be reviewed by other specialists to make sure the anaesthetic is safe for you.

Before your surgery, the hospital will contact you to confirm the time you need to arrive and when you need to start fasting. If you are on a morning list, you need to stop all food from midnight and drink clear fluids only until 5:30 AM or two hours before the planned start, whichever comes first. For afternoon lists, that time is 11 AM.

Clear fluids include water, clear apple juice with no bits, or clear energy drink such as Gatorade. It does not include milk or cloudy juice with pulp.

You will arrive at the hospital between 1 and 2 hours before your surgery. One of our anaesthetists will give you a general anaesthetic, meaning you will be ‘asleep’ for the whole procedure. They may also put local anaesthetic around some of the nerves in your leg (nerve block) to reduce your pain after you wake up.

Small incisions are made in the middle of the front of the thigh and in the shin. Your surgeon uses these to place pins in the bones, which allows them to monitor your leg alignment in real-time using computer navigation.

A tourniquet will be inflated around your upper thigh to reduce blood flow and allow a clear view inside the knee. Your surgeon will then make 2 to 3 small incisions (1cm) at the front of the knee and fill it with sterile saline (salty water).

The telescope (arthroscope) is then attached to a camera and inserted into the knee to look for damage and injured areas. These can be treated with a selection of small instruments. The landmarks inside the knee are then marked out for the computer navigation system.

An incision is made over either the top of your shin bone (HTO) or the bottom of the thigh bone (DFO), close to the knee joint. Cuts are made in the bone and a wedge of bone is either removed or introduced to change the leg’s alignment. The correction is confirmed using x-ray and computer navigation throughout the procedure. Once completed, a plate and screws are fixed to the bone to hold the new position.

The next step is preparing the tibial tubercle through a 10-15cm incision over the front of your shin bone (just below the knee joint). A 6cm section of bone with the patella tendon attached is moved towards the inner knee or further down the shinbone before being fixed back to the bone with screws.

At this point, extra procedures such as an MPFL reconstruction can be performed if needed.

At the end of the procedure, the incisions are injected with local anaesthetic, closed with dissolvable sutures, and glued to provide a strong waterproof closure.

The surgery takes 90-120 minutes on average with additional time before for anaesthetics and after for recovery. Relatives or partners will usually need to wait 3-4 hours between leaving the admissions area and getting back to the day stay ward.

Most patients experience discomfort after waking up from realignment surgery. This is usually well managed with painkillers and the Game Ready machine.

Length of stay

You will be discharged 1-2 days after surgery when it is safe and you feel comfortable.

Walking

You will need to use crutches for the first 6 weeks (If you have your own, feel free to bring them). Following osteotomy surgery, patients are usually not allowed to put any weight through that leg and need to remain in the brace for the first 6 weeks.

Bracing

A brace is used to protect the fixation for 6-8 weeks in total.

Dressings

The bulky dressings can be removed the morning after surgery. You will have small, waterproof dressings underneath (insert picture) that you should leave on until your wound check at 10-14 days. It is common for some fluid to ooze out into the dressings over the first 24-48 hours and this can have a faint red colour to it. If it happens, the waterproof dressings may need changing.

You can shower with these dressings but avoid soaking in the bath,  pool, or the ocean. If they come loose or get soaked, please replace them.

Game Ready

If you have been supplied with a Game Ready. We advise using it on program 2 or 3 and for up to two hours at a time. You can use it as often as you like in a day as long as you manage to complete your rehabilitation exercises. If your pain and swelling are well controlled, you don’t need to use it.

When supplied by MTP Health, you have the Game Ready for 2 weeks. At the end of this time it will be picked up by a courier unless you want to continue to rent it yourself.

Surgeon follow up

You will have your first post-operative visit with your surgeon at two weeks. This appointment is critical for checking your wound healing, assessing your knee’s stiffness, and answering any questions you may have.

Further follow up with your surgeon with x-rays at each visit until the bone has healed:

• 6 weeks after surgery
• 12 weeks after surgery
• 6 months after surgery
• 1 year after surgery and annually ongoing

After one year post-op you will discuss returning to higher levels of activity with your surgeon. After that, you will follow up with your surgeon on a yearly basis.

Return to driving

Returning to driving takes a minimum of eight weeks for right knee surgery and two weeks for left knee surgery in an automatic car. You must be able to safely perform an “emergency stop” and you must have stopped all painkillers other than over-the-counter medications (such as Panadol or Nurofen). There is no specific documentation on this by licensing authorities, but checking with your car insurance company is recommended.

Return to work

After an osteotomy, the knee may remain swollen for up to 6 weeks. The incision sites are often puffy and firm for up to 3 months, and recovery to a point that the knee feels relatively normal for day to day activities can take 3-4 months.

The amount of time it takes to return to work depends on your level of activity. Most office workers can return to work after 2-4 weeks. Heavy manual workers may require 2-3 months before resuming full duties.

Return to sports

Low-impact activities such as walking, bike riding, golf, swimming, and using an elliptical trainer and can start around 3-4 months from surgery. Higher impact activities such as running and sports cannot be started safely until 8-12 months.

Realignment surgery is a very safe procedure, but all joint surgeries carry some general risks.

The most common side effect is temporary pain and bruising. Other complications can include:

Reoperation

There may be a need for another operation if the bone fails to heal, the screws break, or if a large haematoma forms in the wound. The most common reason for reoperation is to remove screws or metalwork that cause irritation after the bone has healed.

Over or undercorrection

Thorough planning and computer navigation are used to make the correction as accurate as possible, but sometimes it can be too changed much or not enough. This may cause ongoing symptoms in the affected side of the knee or the other side of the knee, and another procedure may be needed to adjust the correction.

Blood clots in the leg

These happen in about 5-10% of realignment surgery cases and can cause severe swelling and pain. Clots that develop in the calf are called deep vein thrombosis (DVT) – these can travel to the lungs and cause a pulmonary embolism (PE). If a clot develops, you may need to take blood thinners for several months

Infection

This is very uncommon after osteotomy surgery (1-3%). If it’s just in the wound, antibiotic tablets or an IV drip may be needed. If the infection gets into the knee joint, further surgery be needed to wash the joint out.

Skin numbness

There are very small nerve fibres in the skin around the knee that are always cut during the surgery. This leaves a small numb patch on the outer part of the leg past the scar. This numb patch tends to shrink over time and permanent nerve damage is rare, especially to the larger nerves that supply muscles.

Joint stiffness

Most patients are stiff following osteotomy surgery. This usually settles within the first few days to weeks. Even though modern techniques and early joint mobilisation prevents most stiffness, some patients suffer from excessive internal scarring called arthrofibrosis.

Delayed and non-union of the bone

The repositioned bone may take longer to heal than normal (10-20% of cases). The risks for this are higher in smokers and diabetics. In 1-5% of cases, it doesn’t heal at all and might need further operations.

Other uncommon complications include:

• Anaesthetic risks
• Allergic reaction to medications
• Heart damage
• Stroke

As always with the health system, the answer is ‘it depends.’

At MTP Health, our aim is to simplify healthcare through a better understanding of the system upfront. Therefore, while you can discuss the options specific to you with the team when you see your specialist -

If you are having surgery using your private health cover, the standard fees for the surgeon, anaesthetist, and assistant usually lead to a total out-of-pocket payment of around $4,500. This is the ‘gap’ that is left after Medicare and your insurance company has given you back their rebates.

Note that the anaesthetist is an independent practitioner and can charge a different gap which could affect this figure. We always provide you with their details and recommend you check their quote before committing to surgery.

The surgeons at MTP Orthopaedics participate in the various reduced gap schemes run by different health insurance providers. However, please check for the availability of surgical time slots first as there is often a wait of many months for this option.

Your insurance may also have an excess to pay, so please check. This is usually $500.

If you are having the operation through the public system, there is no out-of-pocket cost.
Unfortunately, you are likely to have to wait up to a year for surgery.