Almost everyone has had a knee injury at some point in their life, and even if they haven’t, they probably know someone who has. Is it because people have weak ACLs, MCLs, PCLs, or is it that our patellas are in the wrong position? Is it that the cartilage behind the kneecap and the menisci are just poor quality, and therefore prone to injury? Is it some combination of these factors? Or is it just that the knee is the scapegoat for the rest of the leg? The knee is out there all alone. It gets the brunt of the force going through the leg, meaning the knee’s neighbours (the hip, ankle and foot) may not be doing their job well enough, and this means there’s overloading of the knee joint. Let’s look at the knee’s neighbours for a sec… The design of the foot is pretty amazing. It is designed for:
- Stability: to be the foundation of support for the rest of the body
- Mobility: to be able to accommodate uneven terrain, yet continue to maintain stability
- Propulsion: to move forward, or in any direction!
And the foot can do all of these things simultaneously, a feat of engineering! The design of the foot allows for a stable foundation to be created across an undulating and changing terrain, and to apply a force to a surface, moving the body. How cool is that? The design of the hip is pretty awesome too. It is designed for:
- Mobility: being a ball and socket joint, the hip can move in every direction
- Stability: it has great stabilising muscles intimately surrounding all 360 degrees of the hip
- Strength: it has the huge gluteals and iliopsoas to generate massive power
But if you lose foot or hip mobility (say, because you sit at a desk all day, or you wear flat shoes and walk on flat surfaces), you will still need mobility from somewhere else in your leg to do normal things (like getting in and out of your car, walking up and down stairs, or putting on your shoes). Often you will attempt to get this lost mobility from your knee joint. The knee, however, is not designed for masses of mobility, in the same way the foot and hip are. The knee is really only designed to work in one plane (flexion and extension). And as you continue to move around, and use the strong muscles of your hips and legs, you will continue to transfer that power through your leg – through the knee. So you can see how the knee will get blamed, because it is the sore bit – when most of the time, the real problem is coming from your hip or ankle. If you have a knee injury, you should expect to have more than just your knee looked at by your physio – to ensure all these other contributing factors are sorted out.