Periacetabular osteotomy (PAO)

What is a periacetabular osteotomy (PAO)?

The hip joint is a ‘ball and socket’ joint, which is quite self explanatory. A periacetabular osteotomy (PAO) is a complex surgery which is only performed in specialised centres, and allows the surgeon to position the hip socket where it is needed.

What happens during surgery?

The orthopaedic consultant will make a single incision in front of the hip below the pant line, known as a bikini incision. Through this they make a series of accurate bone cuts to the pelvis (osteotomies) around the hip socket so that it moves freely and can be positioned where needed. It is then fixed in its new position with 3 or 4 screws. Over the next 6 to 8 weeks the bone heals and eventually the screws are no longer important.

What will my recovery be like?

This is one of the bigger operations performed in children’s orthopaedics and pain control is tackled from many angles. A pain catheter or epidural is often inserted during the operation to give 1 or 2 days relief in additional to regular light and strong pain killers. An expert pain team visits each day to help reduce pain to a manageable level.

After 1 to 2 days the physiotherapists start getting you out of bed. You may also have had a tube inserted into your bladder to drain urine and this is also removed after 1 to 2 days.

For the first 2 months you can only put a little bit of weight through the operated hip whilst it heals. You will be seen regularly in clinic to ensure the recovery is progressing well.

How long will I be in hospital for?

Somewhere between 4 to 7 days to allow time to manage your pain and to be safely signed off by the physiotherapy team. You will have a check X-ray before you go home.

What are the benefits?

The main goals are pain relief and improved quality of life. We hope that by doing this surgery we can preserve the life of your own hip and postpone or reduce the risk of hip replacement surgery later in life.

What are the risks?

There are risks with any operation. These risks are the same for any hip operation but will be explained to you in detail and you will have the opportunity to ask any questions. The key risks are explained below but the complete range will be discussed with you by the surgeon during the consenting process.

Blood loss

This is the most serious risk and there is always some bleeding when making multiple bone cuts and the surgery can take a few hours. We give a special drug to minimised blood loss, called tranexamic acid.

We also collect, clean and return your own blood using suction and a system called ‘cell salvage’. Occasionally we also need to give you donated blood and blood products during or after the surgery.

Infection

This risk exists for any operation. We minimise this risk with antibiotics. Mild infections settle with antibiotics but occasionally deep infections can occur, making you unwell enough to need surgery to drain any pus that may have collected.

Nerve injury

Around 1 in 4 people experience numbness on their thigh after surgery which most patients are not bothered about.

Major nerve injury is rare but can occur and is more serious. It can be temporary or lead to permanent pain, numbness and weakness of the leg requiring splints and or tendon surgery. Across the globe, the reported rate of this is somewhere between 0.5% and 2% which is 1 in 200 to one in 50 people.

Slow bone healing

After surgery the bones can be slow to heal. This is rare in young people but exposure to cigarette smoke will increase this risk. Sometimes the bone doesn’t heal which is called a non-union.

Blood clots

Blood clots in the leg, known as deep vein thrombosis (DVT), or lungs, known as pulmonary embolism (PE), are a very rare risk with pelvic surgery. If you have a family history of clots or take any medication (combined contraceptive pill for girls) discuss this with your surgeon.

Who can I contact if I have any questions?

If you have any questions please do not hesitate to make contact using the numbers below.