If you’re researching common reasons for knee pain, you may have come across the concept of malalignment.
It’s a term that often pops up in online forums and discussion boards. (You’ll also hear it called misalignment.) But what exactly is it – and how would you know if you have it?
Knee malalignment is actually a very broad area, with many different causes, variations and treatments. Also, it’s important to add at the outset that not having perfectly straight legs isn’t necessarily a problem (more on that below!). But there are some simple ways to break the subject down and consider the next steps…
First, a quick definition
What do we actually mean by malalignment? In simple terms, it’s when the bones in your leg don’t line up straight. Imagine a line that runs from your hip to your ankle. In a normal situation, we’d expect this line to run straight down from the centre of your hip joint through the middle of your knee joint to the centre of your ankle joint. (Doctors call this the “long axis of the leg”.) If any of the main leg bones – which are the femur (thighbone), patella (kneecap), tibia (shinbone) and fibula (the thinner bone running alongside the tibia) – deviate from this “neutral” axis, they can pull the knee joint out of kilter.
So what are the classic signs of knee malalignment?
Visual signs of malalignment
There are two main types of misalignment in the knees, and they may be obvious from a simple visual check. If you stand up straight with your feet together, are your knees pointing inwards or outwards?
- Varus malalignment – is when the knees angle outwards and the legs are curved (“bowlegged”)
- Valgus malalignment – is when the knees point inwards, towards each other (“knock knees”)
More rarely, it’s also possible to have varus malalignment in one knee and valgus in the other, so the legs appear to lean in one direction. This is known as “windswept deformity”. But malalignment isn’t always obvious to the naked eye. Another prominent alignment problem is tibial shift, a subtle change or rotation in the shinbone that changes the “fit” of the knee joint further up the leg.
Physical signals
The most obvious physical sign of misalignment is pain or discomfort. You might find this is focused on a particular part of the knee, for instance:
- Pain on the medial (inner) side – can be caused by varus malalignment, because your knee is being pulled outwards, which loads extra pressure onto the opposite side of the joint
- Pain on the lateral (outer) side – can be caused by valgus malalignment, because your knee is being pulled inwards, which overloads the outer aspect of the joint
- Pain on the joint line, where the knee bends – can be caused by tibial shift, because the rotated shinbone has changed the dynamics of your knee joint and the smooth movement of bones and muscles
These pain signals might also happen when you’re doing certain activities; for instance, weight-bearing movements – such as standing up from a chair or doing squats – often cause discomfort when there are alignment issues. Sometimes, also, the discomfort is accompanied by swelling and inflammation, as the knee reacts to the irritation by releasing protective fluid into the joint.
Functional issues
Since malalignment changes the mechanics of the knee, it can also give rise to functional problems. These include:
- Instability – your knee can feel unstable, as though it might be about to give way (especially when you’re putting pressure or weight on your knees)
- Gait problems – malalignment can cause changes in the way you walk or run, for instance if your feet are pointing inwards, or if you have to change your walking movement to avoid pain
- Crepitation – you may notice grinding or clicking noises where the bones aren’t aligning properly
- Kneecap issues – malalignment can cause the kneecap (patella) to track incorrectly – this is known as patellar maltracking
Is malalignment a problem?
Well… not necessarily. In fact it’s reassuring (in some ways!) to realise that very few of us have a perfect leg alignment. If you look at elite footballers, for instance, you may notice that some of them are quite “bandy-legged” (varus knees). This is probably due to a partial growth arrest on the inside of the shinbone, caused by playing lots of football during their younger, growth years – but it doesn’t automatically mean they’ll experience problems with function or pain. Many of us have mild misalignment and will lead full lives without experiencing symptoms. That said, significant malalignment does have the potential to cause issues with knees over time. If the mechanics of your legs mean more weight and pressure is being driven through one aspect of your knee, it increases the risk of injuries (such as a meniscal tear), wear-and-tear arthritis as the cartilage comes under more strain in that area, and other potential complications.
Taking the next step
The good news is that most knee malalignment can be managed effectively with the right approach. The key is getting an accurate diagnosis so you can address the issue appropriately, rather than living with unnecessary pain. Diagnosis of misalignment starts with a physical examination of your legs, followed by imaging – such as a long-leg alignment X-ray that profiles your body from hip to ankles – to see whether and where malalignment is causing problems. From there, we’ll have a clear picture of the next options, whether that’s physiotherapy, supportive bracing, or in rare cases, surgical intervention.
Are you worried about malalignment or pain in your knees? We’ll be very happy to take a look and see what we can do to help. Just make an appointment on the website or call assistant Anita on 01962 826107.
Where can I see you in clinic? Find your nearest location here.
