Sciatica, Part 1: How Your Body’s Brilliant Design Keeps You Free of Sciatic Pain Almost All the Time

The nerves of your leg do some­thing that’s near­ly impos­si­ble. If there were a Guin­ness World Record for “action at a dis­tance,” the motor neu­rons of your low back would be in line for it.

A teen­sy ween­sie nerve cell – the motor neu­ron — lives in the spinal cord in the upper part of your low back. It’s so tiny you couldn’t see it with your naked eye – it’s less than 6 hun­dredths of a mil­lime­ter across.

That tee­ny cell con­trols a long skin­ny exten­sion (called the axon) that grows out of it. The axon gets bun­dled togeth­er with zil­lions of oth­er axons to form the sci­at­ic nerve.

As a com­po­nent of the sci­at­ic nerve, the indi­vid­ual axon reach­es from the spinal cord all the way down to con­trol your big toe – about three feet away.

Pro­por­tion­al­ly speak­ing, that’s com­pa­ra­ble to you stand­ing in Times Square and reach­ing out a long fin­ger to con­trol what’s going on in White Plains, dozens of miles away.

The motor neu­ron does far more than just trans­mit an elec­tri­cal nerve sig­nal as far as White Plains. It also keeps nour­ish­ment and hor­mon­al sig­nals flow­ing all the way out there, repairs dam­age as it occurs, pro­vides immune sys­tem sup­port, and sup­plies every­thing else the fin­ger needs to con­tin­ue as an inte­grat­ed liv­ing body part.

And that’s the easy part

There are haz­ards galore that the sci­at­ic nerve has to avoid while it’s doing its job of con­trol­ling the mus­cles of your big toe.

  • Your body can bend and stretch in any direc­tion, caus­ing strain­ing or kink­ing of the nerve.
  • The nerve has to pass through many mus­cles and con­nec­tive tis­sue sheaths, any one of which could tight­en or swell to put undue pres­sure on the nerve.
  • The discs of the low back could bulge out, putting pres­sure on the nerve just as it emerges from the spine.
  • Your min­er­als could be out of bal­ance, with too much (or too lit­tle) sodi­um, mag­ne­sium, cal­ci­um, or potas­si­um dis­turb­ing the nerve’s peace.
  • Poor nutri­tion could starve the nerve cell at its core in the spinal cord, and make it a chal­lenge to keep send­ing chem­i­cal sig­nals along its long axon.
  • Impaired blood flow could leave the end of the nerve short of ener­gy, oxy­gen, or oth­er nutri­ents.

How does the nerve cell per­form its near­ly-impos­si­ble task while cop­ing with these poten­tial haz­ards?

Brilliant biological design – the basis of health

Before you ever expe­ri­ence a symp­tom, much less phone your doctor’s office for an appoint­ment, the health process is already hard at work inside you. Inter­nal rebuild­ing and repair goes on all the time with­out you even notic­ing.

With­out the robust repar­a­tive nature of your bio­log­i­cal sys­tems, you’d be toast.

But for­tu­nate­ly for you, you have mil­lion years of evo­lu­tion­ary opti­miza­tion built into your body. The redun­dan­cies, con­tin­gency plans and con­trol sys­tems are exceed­ing­ly sub­tle and com­plex — far beyond what sci­ence has so far been able to grasp.  Nobel Prizes in Med­i­cine and Phys­i­ol­o­gy will still be wait­ing to be won a thou­sand years from now.

One could say that sci­en­tists have only deci­phered the first few pages of a long, long Russ­ian nov­el.

It’s not the pills you take, your phys­i­cal ther­a­pist, acupunc­tur­ist, or even your doc­tor of chi­ro­prac­tic.  The cure for sci­at­ic pain is already at work, auto­mat­i­cal­ly, inside you.

That’s the rea­son why your sci­at­ic nerve per­forms just fine almost all of the time.


Deepen Your Body of Knowledge

More on home­o­sta­t­ic con­trol sys­tems

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About Ronald Lavine, D.C.

Dr. Lavine has more than thirty years' experience helping patients alleviate pain and restore health using diverse, scientifically-based manual therapy and therapeutic exercise and alignment methods.

His website,, provides more information about his approach.

Please contact him at or at 212-400-9663.

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