MPFL reconstruction

It is an abbreviation for a reconstruction of the medial patellofemoral ligament, which is the ligament on the inner side of the kneecap, and is the most common surgical procedure for a dislocated kneecap.

What is an MPFL reconstruction?

Here you will have the damaged inner ligament on the inside of the kneecap replaced. MPFL is the name of the ligament that holds the kneecap in place. It is an abbreviation for the Medial Patello Femoral Ligament . The new reconstructed ligament is stronger than the one you have naturally. The ligament runs from the inside of the kneecap/thigh muscle to the inner thigh bone. A tendon from the hamstring is often used to reconstruct this ligament. An artificial ligament can also be used. A tendon from the thigh muscle can also be used. It is important to point out that this is an operation for a loose kneecap and it is NOT an operation for anterior knee pain.  

MPFL reconstruction

The image illustrates what it looks like. However, the screw on the inner side is not yet screwed in. The screw should hold the new tendon in place until it has grown in after about 3 months.

What level of physical activity is safe after an MPFL reconstruction?

There is never any need for a splint, even though it sounds like a safe option. A splint increases the risk of deep vein thrombosis.

There is no need to restrict movement. It is important to bend and straighten the knee as soon as possible so that it does not become stiff.

They may also be allowed to support you with their full weight.

A few days after the surgery, physical therapy involving various exercises should begin.

If a surgeon offers to perform MPFL reconstruction surgery on you because you have pain around your kneecap, you should decline. Even if you’re told that the reconstructed ligament will help your kneecap move more properly.

MPFL reconstruction is good surgery

In most cases with a loose kneecap, this is a very good operation, but there are exceptions. That’s because in some situations, the strain on that ligament will be too great for it to hold up in the long run. In other words, you may need to correct the cause of your patella becoming loose. Therefore, it is important that you always have at least an MRI scan of the knee before your surgery. This is to check if you have trochlear dysplasia or  Patella Alta or Inward-turning kneecaps or another cause of the kneecap dislocating. If you have one of these conditions, there is a significant risk that the ligament won’t hold up over time or that you won’t achieve a good outcome. The same applies if your knee exhibits a so-called “J-sign,” as it is then usually necessary to correct something in your bones as well. Read more  here

After surgery?

What are you allowed to do after an MPFL reconstruction?

You should not wear a bandage or splint, as this increases the risk of deep vein thrombosis and the development of stiffness.

You are allowed to put your full weight on your leg.

You should move your knee up to the point where it starts to hurt; this helps prevent stiffness.

After just a few days, I recommend starting physiotherapy, including training your thigh muscles and learning to bend your knee. 

Sick leave after MPFL reconstruction?

How long do you need to be on sick leave from school or work? That’s a great question as some people are back at work after just 1 week, but it’s all about what you work with and how you transport yourself back and forth and there is a lot of individual variation. If you have a physically demanding job, expect it to take a few months or more.

A Return to Sports?

Where can you resume sports? Of course, it depends on the sport you play, but contact sports should only be resumed after 4 months and when your musculature and balance have recovered. The latter often takes more than 4 months.

Problems after MPFL reconstruction

Unfortunately, I see quite a few patients who have developed complications.

1. The ligament has torn, and the kneecap has become loose again. 
2. I have developed pain in the front of my knee.  

There are a variety of reasons why some people continue to have problems. For example, the ligament may not be attached in the right place on the femur or you may have trochlear dysplasia or you have misalignment of your leg bones, for example an increased femoral anteversion – which means that your femur turns too much inwards and you have  inward-pointing kneecap.

MPFL reconstruction with the use of artificial ligament

The image on the left illustrates an artificial ligament attached to the kneecap.

In recent years, I have routinely used an artificial ligament made of FiberTape. In simple terms, you could say it’s a kind of shoelace that allows your own scar tissue (a type of ligament tissue) to grow into the ligament, so it ends up functioning like your own ligament.

Back in 2005, when I first started performing these ligament reconstructions, I used a tendon from the back of the thigh (gracilis), and later, for a number of years, I used a tendon from the quadriceps muscle, and that worked reasonably well, too.

The new FiberTape method has the advantage that it is not necessary to “harvest” tissue from other parts of the body. Research shows that using artificial ligaments yields equally good long-term results. The downside is that, for the inexperienced, it really doesn’t work well unless the artificial ligament is placed precisely.