To understand how knees can go bad, it is necessary to understand the relationship between all the joints. If one joint is a relatively stable and fixed joint, the joints above and below it are generally more mobile and flexible joints. Such is the relationship of the knee to its neighbors, the hip and ankle.
The knee is a mostly stable, fixed, hinge joint that moves in one plane (with a teensy, weensy bit of rotation), extending and flexing the lower leg. It allows us to sit and stand with ease, to climb and descend stairs, and even fold ourselves into tiny airplane seats. If we didn’t have hinge flexibility in our knees, imagine how unbelievably hard it would be to get up from a chair or climb stairs….seriously, imagine. At the same time, if we didn’t have the lateral stability of the knee as well, we’d be walking around like the scarecrow in our favorite movie about Oz. Part of the stability comes from the structure of the bones themselves, and part from the myriad of ligaments that stabilize the knee.
Above the knee is the hip -- a mobile circumducting joint, meaning it moves in pretty much all ranges around the radius of a circle – side to side, back and forth, at angles, around in a circle. It gives us the ability to move much more freely and with ultimate precision.
Below the knee is the ankle -- also a mostly mobile joint, pointing and flexing to allow us to walk and run and climb stairs, everting and inverting so we can make quick lateral movements as in tennis or quickly sidestepping.
The general relationship from top to bottom is Mobile (hip) – Stable (knee) – Mobile (ankle), and this is the general pattern that follows through the entire body. Happens in the arm, too: Mobile (shoulder) – Stable (elbow) – Mobile (wrist). Problems can arise when a mobile joint like the hip is compromised through injury, wear and tear, or tight muscles; it becomes stiff and less mobile. You know the people in whom this has happened: they shuffle or take shorter strides. Since the body likes to maintain efficiency, the mobile actions the joint used to perform now must fall on the next joint…in this case, the knee. What was previously a unidirectional stable joint, now must try to move in directions in which it wasn’t meant to move. The insidious creep toward dysfunction ensues, and one day we find ourselves suffering from increasingly aching knees and progressing into meniscus tears, cartilage damage, osteoarthritis and more.
The next time your knees ache, don’t assume this is simply an unfixable outcome of age or injury. You may be able to nip this pain in the bud by examining how ALL your joints are working together. Gaining correct mobility in your hip or ankle may be the solution to easing knee pain. Find a good massage therapist to help balance the body by easing tight, overly-facilitated muscles and activating the weak, inhibited ones. Further follow-up with a physical therapist, trainer, yoga instructor or Pilates studio can continue to improve function and range of motion in your hips and ankles so that your knees can go back to doing their job of stabilization.