Wednesday, November 23, 2016

Sciatica - Too Broad A Term For Leg Pain

By Dr. R. Greg Lusk, DC
Over the years I have listened to many patients tell me that they have "sciatica".  Either they think they do based on what they found after a Google search, another healthcare professional has told them that they do, or a well-intentioned friend or family member has made the suggestion.  Sciatica is a term often used broadly to refer to pain or other symptoms, such as tingling or numbness, in one or both legs.  However, it is often used incorrectly to describe pain from another nerve and in and of itself offers very little value in understanding the source of one's symptoms.  It's similar to being told that you have tendonitis.  Tendons attach muscles to bones, and because we have many muscles we also have many tendons.  Saying that you have an inflamed tendon ("itis" = inflammation) doesn't inform someone where certain treatments (e.g. laser/ultrasound/soft tissue therapies) should be applied or what actions/exercises should be avoided, or done, to assist with recovery.  The same holds true for sciatica, but understanding the source is crucial to successfully managing the condition.
The sciatic nerve is like the trunk of a tree.  There are various roots that come together to form the "trunk" and then the trunk offers up many branches.  This nerve is the longest and widest in the entire body and forms deep in the pelvis as 5 nerve roots (L4&5,S1,2,3) come together.  It exits the back of the pelvis through deep buttock muscles and then runs down the back of the leg where it distributes its various branches.  It is responsible for sensation of the skin on the back of the thigh, the outside front and back of the calf, and most of the foot.  It does not supply the inside, front, or outside parts of the thigh, or the inside of the shin and foot.  Therefore, if that is where your symptoms are, you do not have "sciatica".  Furthermore, the sciatic nerve is the power source for the muscles on the back of the thigh (i.e. hamstrings) and all muscles of the shin and foot.
If you do have symptoms in the correct area(s) the question still remains - "Where is the source of irritation?"  Frequently, where you feel symptoms (i.e. the leg) is not where the problem is and often pain relieving efforts are directed at the smoke but not the fire.  Often a nerve root in the back is the site of irritation and this is more properly named a radiculopathy.  This could be due to spinal disc degeneration and resulting arthritic changes (a.k.a. stenosis), a disc bulge/herniation, or slippage/excessive movement between vertebrae (spondylo-listhesis).  Sorry for the tongue-twisting mouthful!  In each case, the management of symptoms could involve aspects that are quite different.  For instance, disc bulges often respond best to exercises where you bend backward whereas relief from stenosis symptoms usually occurs by bending forward.  This illustrates why "sciatica" as a diagnosis doesn't really cut it while something like "L4/5 Disc Bulge with a right L5 Radiculopathy" is much more informative.  Furthermore, this doesn't even consider the fact that muscles and joints, namely the sacro-iliac (SI) joint or hip joint, other soft tissues (e.g. bursae), or irritation to the sciatic nerve and its branches along its path, can refer symptoms into the leg as well.
Differentiating the cause of your "sciatica" is empowering as it clarifies what activities you should refrain from or participate in, providing you with a sense of control over your symptoms. 
This article is for general information purposes only and is not to be taken as professional medical advice.

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