MOVE: 7/10/15 Heading South of the Land of Leverage - the Achy Knee

Spoiler Summary - heading south to the land of leverage....the achy knee.

After a short break last week, we're back on our journey around the functioning body.  This week, to one of the most commonly over-stressed, all-too-cranky and sometimes noisy parts of the body....the place where the tibeofemoral, the proximal tibeofibular and the patellofemoral joints all come together....the place where the ACL and PCL cross paths and the place where, if the rate of discomfort were to continue to increase at the rate it has from the 70's (up 65% from 1974 to 1994 for example) most of us will ache in retirement.....more commonly known as "The Knee".

 

The knee is another one of the marvels of the human body.  It allows us to get up, move around and walk tall.  However, with the relatively long boney levers (femur and tibia), the instability that comes with a round surface (femoral "condyles") sitting on top of a flat surface (tibial "plateau") it is inherently unstable and therefore at-risk for faulty movement.  Faulty movement that lasts long enough increases the odds of an injury and commonly grows up to become discomfort.

However there's VERY GOOD news - most of the knee pain that people experience, especially the kind that comes on without a specific traumatic event (they just begin to ache), is preventable entirely or can be corrected.  

It's in this arena that most of the effort has been placed for knee injuries.  Whether it be in athletes and attempts to reduce the rate of ACL tears, or in the more common (and sometimes obscure) "behind the kneecap" (patellofemoral) pain syndrome that so many experience, the greatest clinical impact tends to be "normalizing movement".  Even when compared to certain surgeries, when you consider the whole picture, normalizing the way the body works is best.

So what is "normalized movement"? Well....it's temping to say it should bend 130 degrees and extend fully, that's what you'd find in a textbook, but it's a bit more nuanced than that.  During every step you take the knee not only bends and straightens...it also twists slightly, moves side to side a little and the kneecap (patella) slides around a bit.  These are called accessory motions and they are critical for normal movement.  However, too much of a good thing can become a very bad thing, with these movements often becoming a source of dysfunction and eventually discomfort -- Too much motion in one (or a couple) accessory movements and things "ride" funny.  Too much motion in all areas and the entire joint may become unstable.  Too little movement because things are compressed, and things grind and wear-out faster than they should.  So...much like the rest of the body...it's a goldilocks premise:  not too little, not too much, just right.

Although it often takes a trained eye to tease out various "movement faults" and therefore suggest specific corrective strategies, here are six things anyone can do to minimize risk of injury and pain.

1. Keep your HIPS flexible and strong.  Yep....HIPS.  Although it seems to make sense that knee pain is a result of knee problem, this logic hasn't proven out in all cases.  Remember the "leverage". More commonly, hip motion (or lack of) dictates the position of the knee....and therefore how it moves.  Keeping hips flexible and strong can keep the forces on the knee more normal.

2. Keep your body weight in mind.  This one is pretty straight forward -- the more weight we are carrying, the more compression on the knees.

3. Stay hydrated.  The soft tissues between the knee and the ligaments that hold it together all rely heavily on water for health.  Without proper hydration they become more stiff than they should be and are more susceptible to injury.

4. Remember nutrition always matters. Not just from a calories or weight perspective, but also from an inflammatory one.  Certain foods contribute to inflammatory conditions and the joints are just as much at risk as other areas - gout is an excellent example (see "current understanding" here).

5. Protect your knees. Quick loading (like jumping on/off things), twisting (changing direction quickly) and high-load positions (like deep squatting) all increase risk.  Although these should probably be avoided outright in many situations, when not possible, minimize the reps or duration. 

6. Keep MOVING.  Remember, the body was built to move.  Stationary postures allow surfaces to get (relatively) dry and stiff. Consider motion breaks (i.e. "unwind" by going in the opposite direction) for 15-30 seconds here or there when you can.  If you're sitting, stand.  If you've been on your feet all day, sit.  If you're stationary, MOVE.

Of course, there are many more than we can list in one post....and we're happy to keep the conversation going.  Let us know if you have questions.

Have a great weekend,

Mike E.