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Patient Education: Diseases Conditions Treatments & Procedures

Back pain


Did you know that there are two kinds of people in this world? Those with back pain, and those who will get back pain. Back problems are a common and unfortunately an unavoidable fact of life. Ever since we started walking upright on our back legs, we were doomed to back pain. But you need not despair! Your body has actually compensated for this upright posture, but with occasional overuse or abuse, OUCH! There goes that back.
To understand the most common form of back pain, or as we call it myofascial pain, a short lesson in physics and levers is in order.

A lever is like a teeter todder. The middle is the axis (or center of rotation) and each end is a seat where you sit. Here is a test: Let us assume that both kids (Jack and Jill) in the seats are the same weight. If instead of the axis being right in the middle, if it is moved to toward Jack, would Jack now need to be heavier or lighter than Jill in order to balance on the teeter todder like before?

Well if you flipped a coin, guessed or calculated with a pencil and ruler no matter. The answer is more weight. That is because Jill is further from the center of rotation and the effect of her weight that Jack must counterbalance is magnified by a greater distance. A simple equation states that force is equal to mass times distance. Jack must counterbalance the forces that Jill’s side has by his own equation Force = Mass X Distance; but his distance is shorter so his weight needs to be more.

Part II of the quiz is, who initially described that principle. (Hint, he wasn’t a spine surgeon but thanks to him we understand back pain).
Answer: Sir Isaac Newton

So what does this have to do with back pain? Your body is like a teeter totter. The spine is the axis and the muscles in your back are balancing your weight in your front. The back muscles must exert a constant force (or contraction) to hold you upright and counterbalance your front load ie stomach and anything else you carry.
If you carry objects in front of you, the more weight or the greater distance in front of you will increase the force your back muscles must exert. So now you can appreciate when your doctor says, lift with bent knees and a straight back, get rid of that belly or suggests exercise to strengthen your back muscles.

Overview (click the video player below to view):

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