Medial patellofemoral ligament (MPFL) reconstruction
MPFL reconstruction surgery used to treat kneecap dislocations or instability.
The surgery uses a graft to reconstruct that ligament. This helps stabilise the kneecap and reduce the risk of more dislocations.
It’s most effective in patients who had no issues with their kneecap before a traumatic kneecap dislocation, then find they cannot trust their knee anymore.
MPFL reconstruction surgery used to treat kneecap dislocations or instability.
When the kneecap dislocates, it stretches or tears the ligament that sits on the inner (medial) knee and connects the kneecap (patella) to the thigh bone (femur). The ligament usually keeps the kneecap in its groove as the knee bends – when it’s torn, the kneecap is at higher risk of popping out of its groove again (dislocating).
The surgery uses a graft to reconstruct that ligament. This helps stabilise the kneecap and reduces the risk of more dislocations.
It’s most effective in patients who had no issues with their kneecap before a traumatic kneecap dislocation, then find they cannot trust their knee anymore.
Other procedures are sometimes needed alongside an MPFL reconstruction. These include:
- Tibial tubercle osteotomy (TTO)
- Trochleoplasty
- Knee arthroscopy
The most important preparation is to have a ‘settled’ knee with no effusion (extra fluid) and to get the quadriceps (thigh muscles) as strong as possible. The best results are achieved when working with a sports specialist physiotherapist who is in communication with your surgeon.
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 and can usually go home on that same day (day case 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.
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 next step is preparing the graft material. This is usually synthetic, but the surgeon might harvest one of your hamstring tendons to use as a graft in some cases. To access the hamstrings, a 3-5cm incision is made over the inside of your shin bone (just below the knee joint).
The graft is passed under the skin and soft tissues, going from a 3-4cm incision on the inner edge of the kneecap to a 2-3cm incision on the knee joint’s inner edge. The graft is then fixed to the kneecap with sutures: these are secured into patella bone using anchors and screwed into a tunnel drilled in the femur.
At the end of the procedure the incisions are injected with local anaesthetic, closed with dissolvable sutures, and glued. This creates a strong waterproof closure.
The surgery takes 1-2 hours 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.
You should experience little more than mild discomfort after waking up from an MPFL reconstruction. Recovery is usually fast and you will only need painkillers for a short period.
Length of stay
It is safe for you to go home on the day of your surgery. If surgery is later in the day, you may wish to stay in the hospital overnight for comfort.
Walking
You will be given crutches to use before leaving hospital for your safety (If you have your own, feel free to bring them). Most patients can put all their weight through their leg immediately after an MPFL reconstruction and are walking normally within 2-4 weeks.
Most patients can walk normally 7 days after surgery and can return to most activities in 6-8 weeks. Check with your surgeon before starting any impact activity such as running to avoid damaging the knee.
Bracing
A brace is used to restrict bending in some cases. If needed, it will be used for about 8 weeks 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, please click here for information on how to set it up. 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.
It is vital that you engage with a physiotherapist to maximize your early recovery from surgery.
At MTP Health, we recommend booking your first post-operative Physio appointment as soon as we have a confirmed surgical date. This should be 2-5 days from the surgery. We will communicate the rehab plan with your treating physio, whether they’re one of our team or your own. They will help you manage swelling and stiffness before working on your leg strength and function. Finally, they will help improve your level of function for your chosen sport or activity and develop your program to reduce the risk of further injury.
The MPFL rehabilitation protocol we use is based on years of research and experience.
Return to driving
Returning to driving takes a minimum of six 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 licencing authorities, but checking with your car insurance company is recommended.
Return to work
After MPFL reconstruction, the knee may remain swollen for up to 6 weeks. The incision sites are often puffy and firm for up to 3 months. Recovery to a point that the knee feels relatively normal for day to day activities takes 6 months. The full rehabilitation program to reduce the risk of graft failure and further dislocations takes 1 year.
The amount of time it takes to return to work depends on your level of activity. Most office workers can return to work after 1-2 weeks. Heavy manual workers may require 2-3 months before resuming full duties.
Return to sports
Returning to high risk sports such as netball, soccer, footie and basketball takes at least 4-6 months. Achieving this involves sticking to your rehab program under the guidance of your Physiotherapist and Exercise Physiologist. Returning to sport earlier than 9 months or before you’ve achieved your strength, balance, and function targets will increase the risk of the graft failing and further dislocation.
MPFL reconstruction 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:
Blood clots in the leg
These are uncommon after MPFL reconstruction but 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
Pain at the hamstring graft site
You may feel pain or discomfort at the site the donor tendon was taken from. This is generally not too severe and can be managed with painkillers. If it persists or can’t be managed, make sure to notify your doctor.
Infection
This is very uncommon after MPFL surgery. 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 MPFL 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.
Rupture of the graft
The reconstructed ligament is at a greater risk of re-rupture during the first 3 months of rehab (whiles it regains a blood supply and the quadriceps is strengthened and retrained).
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 mission 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 $3,500. This is the ‘gap’ that is left after Medicare and your insurance company have 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 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.