Why Your Knees are Your Biggest Weakness

Knees are the most commonly treated joints at WLP and, unfortunately, this is unlikely to change. If you’re at all active, you’re at risk of a knee injury and though you can prevent the likelihood of suffering one, the weaknesses of the knee are simply down to its anatomy.

Let’s start by comparing to the hip, a deep ball and socket joint where a concavity in the pelvis (called the acetabulum) wraps around the rounded head of the femur, enclosing it in solid bone. Not only is this joint incredibly sturdy, it also allows for a circular range of motion that makes it well suited to twisting and turning.


The knee, on the other hand, is a hinge joint. The rounded bottom of the femur (your thigh bone) sits on top of the relatively flat surface of the tibia (shin bone) and are held together by ligaments and muscle, which – unlike the bone of the acetabulum – can be sprained and torn. Floating on top is the kneecap, which slides up and down through a groove in the femur called the patella groove.

Seif_knee anatomy01

Not only is the knee structurally less stable than the hip, it’s also far more restricted. As a hinge joint, the knee can move forwards and backwards with a very limited amount of twisting. The moment the knee is no longer aligned with the foot it relies on the ligaments and muscles for its stability. Push them too far and they become injured.

That’s why – as David showed with Leigh Halfpenny’s ACL injury – even the most hardened athletes are so often knocked out by a knee injury.

This weakness is a problem in any activity that involves a lot of twisting and turning, with the risk of injury further increased if it’s a team sport where someone might fall across you. Tennis and running pose some danger while football and rugby are high risk.

Worst of all is skiing, where not only do you constantly twist and turn but your ankle is locked in the boot. One nasty fall, and your knee can twist while your ankle will be unable to absorb some of the load.

If you’re a woman, you’re more susceptible to knee problems, as the angle (it’s called the Q angle) of your thighs from your pelvis naturally causes the knee to twist slightly more frequently. You’re also more at risk of the kneecap sliding out of its patella groove (called patellofemoral maltracking), often caused by imbalances in muscle strength pulling it out of place.


Male or female, young or old, you should always get knee pain checked out. Some aches and pains are normal if you exercise but if you’re feeling them in the knee then something’s not right. Don’t shrug off knee pain, even if it’s mild. Treatment is much quicker if we can work on the problems before they result in an injury, which can require months of rehabilitation.

So, what can you do to prevent knee injury?

The most obvious answer is that if you’re relying on muscles and ligaments to support the knee, you want the muscles to be as strong as possible.

Exercises such as lunges and squats are often the simplest exercises to keep the knee and hip strong and supported.  However for the joint itself one of the most important things you can do is improve your “proprioception”.

What is proprioception?

Look straight ahead and raise your arm out to the side without looking at it.  Try and make it horizontal.  Now look at your arm.  Amazing! You made your arm horizontal without needing to look.  It is “proprioception” that enables us to know the position of our joints, without looking.  The joints and ligaments are dense with nerve fibres that tell our brain exactly what position they are in.

It’s important, because if your proprioception or joint sense isn’t good enough you significantly increase the risk of injury.  The better your proprioception, the more your body can correct itself without you having to think about it. That means that when you’re running and your stride lands on an uneven surface, your body knows how to respond without damaging your knee. At a more advanced level, it’s how athletes are able to make their incredible feats seem so effortless.

Proprioception can be improved in many ways, however if we’re talking about the knee then we need to talk about balance.  Balance exercises do more than just increase physical strength, they also improve your proprioception. For the knee joint itself, simply standing on one slightly bent leg with your eyes closed is excellent for improving your joint sense as the knee and muscles around it have to work constantly to keep you upright. Moving your head side to side makes this even more difficult by depriving you of inner ear balance.

By removing sight and inner ear balance, you’re training your brain to keep track of where each of your joints is positioned without help from your eyes and ears.

Proprioception is fascinating and one of the many benefits of regular exercise and activity. Simply put, the more you use your body, the more it knows what to do without you telling it. If you feel like your body isn’t doing what you want, then it’s time to come and see us.

Keep Moving!

cameron tudor physio notting hill   Cameron Tudor

    Clinical Director, West London Physiotherapy

For any other questions regarding this topic please do not hesitate to contact West London Physio on 0207 937 1628 or email me at cameron@westlondonphysio.co.uk