My JHS: Everything's Connected series aims to educate how hypermobility affects not only isolated body parts but also to connect the dots in order to show how it leads to problems that may seem unrelated.
Today we're talking about the knee! I wanted this to be the first body part to tackle because I've never really had any problems with my knees, until recently so I wanted to get to the bottom of it. Turns out the relation to knees in hypermobility is more complicated that I could have ever imagined. You might be surprised that hyperextended knees can cause flat feet, hollow back, and hip pain. First, let's take a look at how the knees work for us and what exactly a hyperextended knee is.
A normal knee can only extend to the point where the thigh and the lower leg are aligned in a straight line. In this picture, you see the many sturdy ligaments at the back of the knee which serve to block the knee from extending beyond a straight line.
If these ligaments are lax, the knee can extend beyond a straight line aka hyperextension. The knee on the left is normal range versus the hyperextended knee on the right. Hyperextended is typically determined by the joint moving 10 degrees passed its normal range.
Google supplied a perfect example of what knee hyperextension looks like - almost like a broken leg!
Developmentally wise, children who stand with their knees in hyperextension will have a hollow back with an anterior tilted pelvis (tilted forwards). The hollow back can turn into lordosis, a serious spinal deformation. It's characterized by the excessive inward curving of the spine, which causes your belly to push forward and your booty to stick out more. The tilted pelvis can lead to a tight or strained piriformis muscle, a small muscle at the base of the pelvis (in the bum). It can also cause a feeling of tightness in the hip flexors as the hips are strained by the angle they're forced into. In my case, my hips are also hypermobile, so even though they feel tight they still have a considerible amount of flexibility, making stretching them more harmful than beneficial until they're strengthened.
Lordosis is something I started to develop as a result of my hyperextended knees. Before I knew what it was, it became a point of personal insecurity because it made me feel like my stomach was fat/bloated when in fact it was my spine curving. It made no sense to me why I would look "bloated" in photos when I really wasn't. I thought it was natural for my body to curve that way until I started to compare my back to what a normal spine looks like. I get muscle spasms in my back frequently, so I'm actively working to strengthen it. It's an issue I'm still working to correct in my own body. I have to be conscious of my posture 100% of the time because my body still wants to slip into that position. You can see what I'm talking about in the photo below in the side bend I was demoing.
How can you correct it?
Strengthening your muscles is vitally important - throughout your entire body but in this case specifically in the abdominal region to help counter the curve of the spine. Engaging the abs in both yoga poses and in daily life will eventually work to correct it over time. Not hyperextending your knees is key since it's what caused the problem in the first place. In forward fold, locking my knees all the way probably leads to me not being able to feel the stretch. I have to microbend my knees and sometimes even modify with rag dolls and an extreme bend in the knees to really actually feel a hamstring stretch! The last key here is to tuck your pelvis under to correct the tilt. Strengthening your hip flexors and glutes helps with this! In the graphic below you can see how hyperextending the knees stack the joints further back so the body has to balance by pushing the pelvis forward. This subsequently causes the upper abdominals to shift forward which puts compressive force on the lower back, causing lordosis.
Increasing your proprioception (your awareness of your body's positions and movements) is another huge way to help correct it. Hypermobile people have a severe lack of proprioception and the only way to gain it is through exposure and practice. When I first started, I had to exclusively work out in front of a mirror so I could see the motions my body was making to ensure my body was making the right movement and my form was correct. I also hired a trainer to help coach my form because I had absolutely no idea what my body was doing. It took many sets, but eventually muscle memory took over to the point where I really only need to be in front of a mirror if I'm trying a new exercise.
Flat Feet + Weak Ankles
Weak ankles can lead to chronic sprains. Weak ankle ligaments coupled with tight hips and hyperextended knees can lead to flat feet. Flat feet aren't genetic, but the result of how you use your body. The tucked pelvis causes your femurs to roll in so the feet tend to turn out which literally crushes your arches into the ground during standing and walking. It also comes full circle by allowing your knees to bypass their normal range and continue to extend past straight to lo and behold: hyperextend. This is how knee hyperextension can happen or develop as a problem when walking!
The quick correction for this is to focus on keeping your feet straight while you're walking and externally rotate your legs. If you're not sure how to externally rotate your legs, try sitting down with your legs stretched in front of you and try to get your pinky toes to touch the ground while keeping your legs straight - your hips should start externally rotating your legs. Now, try it while standing and you'll find that you feel your arches slightly pulling up - effectively being activated and correcting the flat foot problem!
Make sure you sneak in some ankle and calf strengthening exercises into your routine too!