What is an MPFL Reconstruction?

The medial patello-femoral ligament (MPFL) is the main stabiliser of the inside edge (medial) of the patella (knee cap). This ligament prevents the patella from dislocation to the outer (lateral) side of the knee. With any lateral displacement of the patella the MPFL can be injured or torn, leading to recurrent dislocations or partial dislocation (subluxation). These types of injuries typically occur during a twisting or turning mechanism of the leg. Repair of the MPFL is a surgical reconstruction to return the patella to its normal state within the knee.

Left Knee

The Procedure

The operation is done under general anaesthetic (when you are asleep). It is done using a minimally invasive technique called an arthroscopy, meaning that scarring and risk of infection is minimised.

5 small incisions (cuts) are made around the knee to access the joint.  An instrument, called an arthroscope (a long thin telescope with a video camera), can is inserted into the knee. The surgeon will examine the joint by looking at images sent by the arthroscope to a computer screen and repair damaged structures as necessary.  A small portion of the hamstring is then passed through small drill holes in the knee cap. The other end is then inserted into the inner aspect of the thigh bone using a plastic screw to hold it in place. This stabilises the movement of the knee cap. This procedure takes around one hour.

The benefit of operating through small incisions like this is that there is minimal disruption to the surrounding tissues allowing you to progress quickly with rehabilitation and return to normal function as rapidly as possible.

Benefits of Surgery

Success rates are high in terms of improving function and reducing instability of the patella:

  • Improved knee stability with reduced chance of patella dislocation
  • Improved function/mobility
  • Reduced pain
  • It may take up to 12 months for a full recovery and return to sport

Some people will have persisting symptoms depending on the anatomy of their knee joint, any damage already done to the bone surface and how well they engage with their post-operative rehabilitation in physiotherapy.

This leaflet will help to explain what you can do to ensure that you have a good recovery and minimise complications. It will also help you understand what to expect and what is normal after an MPFL reconstruction. A member of the physiotherapy team will generally see you prior to your surgery to provide advice, exercises and to issue you with crutches.

Immediately after theatre

You can start your exercises as soon as you remember to when you return from theatre, you will find them in this booklet. Your knee will be wrapped in a thick bandage but you should try to start moving your knee as much as the bandage allows. Staff will help you to get up with the crutches when you have recovered sufficiently from the anaesthetic.

Before you are discharged you will be given specific advice about your wound care and pain relief. The leaflet contains general information about this. It is normal to be discharged the day after your surgery.

Wound care

The small wounds from the arthroscopy will usually be closed with a single stitch and a paper strip. These are covered with a see-through dressing and your knee is then wrapped in a layer of cotton wool and a crepe bandage. You should keep this bandage dry and leave it undisturbed until your clinic appointment two weeks post-op. This is where your wound will be reviewed and stitches removed.

If at any time you notice any discharge, smell, irritation, or redness around the wounds/dressings, you must contact your GP.

Managing your pain

Although you will only have small scars, this procedure can be painful due to the surgery performed inside your knee. Although the operation is to relive pain, it may be several weeks until you begin to feel the benefit. It is important that you keep the pain under control with regular pain relief medication.

It is likely that your pain will be well controlled immediately post operatively as local anaesthetic is usually placed into the joint during the procedure. It is therefore sensible to take some regular pain relief so that when the local anaesthetic wears off you remain comfortable.

Should you experience any increase in pain and swelling not relieved by elevation and rest, or any pain in the calf, please consult your GP.


Ice can be a very useful tool to help with both swelling and pain.

You should be cautious with its use to ensure that you do not damage your skin. We suggest that you follow the precautions below:

  • You should ensure that the area to be treated is sensitive to temperature by placing a cold and then a warm object against it and making sure you can tell the difference.
  • Use crushed ice, gel packs or even frozen peas as an icepack but always ensure that there are 2 layers of towel between your skin and the ice pack.
  • Check the skin beneath the ice pack after 10 minutes, the skin is likely to be red but should not be white or blue. If you are concerned then the ice pack should be removed immediately. If your skin is frail or has poor circulation then you should check it after 5 minutes. If there is no adverse reaction then the pack can be reapplied for a total of 20 minutes
  • Ice packs are most effective when applied for 10-20 minutes every 3-4hours.


Managing swelling

Your knee may swell for a couple of months or even longer after the surgery. It is normal to have occasional swelling for up to a year. This is a normal part of healing but if it does become excessive this can lead to increased pain and slower return to activities. To prevent this, sit with your foot elevated higher than your hip whenever possible and pace your activities (especially for the first week after the surgery).

If at any time you notice any discharge, smell, irritation, or redness around the wounds/dressings, you must contact your GP as this could be a sign of infection.

Swelling naturally peaks at 3-5 days following an injury or surgery.

Using crutches

You will be issued with and taught to use crutches by a member of the physiotherapy team, usually before your operation. You will be able to fully weight bear unless told otherwise. This will help the healing process.

Normally you will place the crutches forward first, followed by the operated leg and then the un-operated one. The nursing staff will ensure you are walking safely with your crutches before you are discharged.

As a general guide you only need to use the crutches for comfort and to prevent you limping. You need a good walking pattern with knee control before you discard your crutches (this is usually between 3-6 weeks after the sruegry). If you decide you only need to use one crutch we advise that you use the one on the side away from the operated leg to keep you well balanced. You should only move on from 2 crutches to 1 crutch or 1 crutch to no crutches when you are able to do so without limping.

When going upstairs we suggest that you take one step at a time lead with the UNOPERATED (strong) leg. Follow with the OPERATED leg and the crutch, one step at a time. When going downstairs place the crutch(es) on the step below, followed by the OPERATED leg before bringing down the UNOPERATED (strong) leg to join it.

Always use a hand rail or bannister, if there is one available, during your recovery.

Post-operative follow – up

You will require to have outpatient physiotherapy following your surgery to improve strength and stability around the joint. We will usually contact you at home to arrange this appointment within a few days of discharge. The surgeon will decide after the operation when he wants to see you again. You will usually return to the orthopaedic clinic 2 weeks after your surgery. This is so your stitches can be removed and your wound reviewed. Future appointments are made after this as required.


It is important to start exercising soon after your surgery to ensure that you return to normal movement, strength and activities as soon as possible. After your injury the muscles surrounding the knee would have become weak. The strength of the thigh muscle (the quadriceps) is vital to knee stability and reduce risk of further injury. It is important to perform the following exercises 4-6 times per day. We suggest that you exercise little and often throughout the day. Slow controlled exercises are more effective and more comfortable than quick movements. You may experience some discomfort initially with these exercises but it is important not to push into pain. If your pain persists please contact your GP or physiotherapist.

1. In sitting or lying with your leg supported, tighten thigh muscles and straighten the knee as far as you can. Repeat 10 times.

2. Sit or lie with your legs out straight. Gently and slowly slide your heel towards your bottom until it feels tight, then slowly straighten your leg. Do this as pain allows. As your knee bend gets easier you can practice bending your knee while sitting in a chair. Repeat 10 times.

3. Rest your ankle on a small rolled-up towel and let your knee rest into a straight position. To get even straighter, tighten your thigh muscle and push the back of the knee towards the bed. Repeat 10 times.

4. Place a rolled up towel under your knee. Lift your foot and lower leg up to exercise the thigh muscle. Repeat 10 times.

5. Keeping weight evenly distributed between both legs, gently bend both knees a little way as comfort allows and then push up tall again. These exercises help to strengthen the thighs. Some people will find them easier to do while leaning against a wall or holding a work surface. Repeat 10 times.

Returning to normal activities:


People normally return to driving 4-6 weeks after their surgery.

You have to be able to do an emergency stop in a car to be safe to return to driving. It may be worthwhile contacting your insurance company to find out when they would be happy for you to return.


Your return to work will depend on your job. Please discuss this with your doctor or physiotherapist.


Your return to sport will depend on the type of activity and the level you play at. Please discuss with your Physiotherapist what sports you can do and when. You may commence light jogging after 3 months, with a return to sport 4-6 months.


We advise you to refrain from flying for at least 6 weeks after surgery.

Contact details If you have a query about exercises or movements, or have not seen a Physiotherapist before being discharged home please contact: Yeovil District Hospital Therapy Department on 01935 384358

Ref: 34/20/01 
Review: 10/22