What is runner’s knee?
The most commonly injured body part in runners is the knee, so it’s going to be pretty likely that during your marathon training you may start to experience some discomfort in your knees. The most common injury affecting the knee, would you believe it, is called runners knee! This is a lay term for patellofemoral joint dysfunction, pain that you will feel around the kneecap – mostly at the front or the inner side of the kneecap, or behind the kneecap itself. It’s a condition brought about by two things, 1) biomechanics and 2) training load.
Biomechanics means how are you are built and how you move. In the case of kneecap pain there may be certain muscle imbalance which sets up a condition where the kneecap can rub on the underlying thigh bone irritating and wearing the cartilage on the underside of the kneecap. This makes the area inflamed and generates pain. What we typically see is tight and weak glutes, a tight IT band and a week VMO – the quadriceps muscle which sits just above and to the inner side of the kneecap. This smaller muscle is often underdeveloped or overpowered by the larger out thigh muscle. The remedy for this type of knee pain is to work on flexibility in the glutes and also strengthen the glutes and the VMO.
Top 3 exercises for runner’s knee
– Foam rolling the ITB and quads
– Strengthening the VMO
– Strengthening the gluteus medius
The VMO contributes to straightening the knee from a full knee bend and also locking the knee out straight. So, doing exercises which strengthen both portions of the range of motion is imperative. This means you need to do exercises such as step ups, just working on locking the knee out straight from a 20° bend, and also doing split squat or squats where you go into full flexion allowing the VMO to get you out of the bottom position.
The gluteus medius is best strengthened initially in an isolated position such as doing clams and top leg raises. Then the exercise should be progressed in to loaded weight bearing exercises such as step up and wall slides.
Another great trick for helping to manage the symptoms of patellofemoral joint syndrome is to use tape. There are different types and methods of typing, my preferred method is to use K tape and create a small horseshoe underneath the kneecap dragging it upwards and inwards to straighten the kneecap and allow a smooth movement with the underlying thigh bone. This can sometimes immediately unload the kneecap and alleviate the pain.
Load management for runner’s knee
My final trick for helping to resolve kneecap pain is to manage the loading it takes. People typically get their training volume wrong, overloading the patellofemoral joint creating the aggravation. Whilst you are correcting the muscle imbalance you need to decrease your training load sometimes by as much as 40 or 50%, especially running. In the meantime, you can take up cycling to maintain your fitness. Cycling is a great exercise as it helps to buff and polish the underside of the kneecap, smoothing the surface of it. This is known as chondral conditioning and along with physiotherapy treatment, taping and home exercises, it is very useful for managing your kneecap pain.
In the vast majority of cases the things listed above resolve the pain over the course of 4-8 weeks. If physiotherapy is not helping then there is one thing that might help. You would need to see a sports physician for this though. They may be able to inject the knee with Ostenil, a compound that contains sodium hyaluronate (hyaluronic acid is what make your joint cartilage and providing some raw material might actually help to re-generate some of the worn out area. It’s almost like injecting some lubricant in to the knee. I have had a few PFJ patients who have seen quite good results from this when MRI’s have shown quite extensive wear of the PF joint.