“Sciatica” is a very general term used for any pain in the sciatic nerve. The sciatic nerve is the longest nerve in the body, arises from the spinal cord low down in the back, and proceeds down the back of the leg, breaking up into divisions which go dear to the toes.
It is reasonable to expect, therefore, on account of its length, that many irritative factors could produce pain in this nerve. Indeed, it is customary in medical circles to consider sciatic pain under two divisions: (1) pain of the nerve itself, and (2) pain of the nerve due to inflammation or pressure on the nerve from disease of the structures through which it passes.
Among these latter might be dislocation of the sacro-iliac bones in the pelvis, such inflammation as from appendicitis, or inflammatory disease of the female organs.
Probably the most frequent cause of pain of the nerve itself is due to infection somewhere in the body far away from the sciatic nerve itself, such as in a tooth or tonsil or gallbladder.
The treatment of sciatica will obviously depend on the cause. In the case of dislocation of the pelvic bones, support to these by means of corsets, or pads, or casts, usually gives relief.
In few cases of the disease is it possible to give very much relief by means of drugs by mouth. In the primary form of neuritis of the sciatic nerve, removal of focal infection frequently does good. But by all odds the best treatment in the acute stage and the treatment most often neglectedis rest in bed.
It is possible to kill the pain in the sciatic nerve by injecting anesthetic substances directly into it. A long hypodermic needle can be thrust down through the skin until it reaches the nerve: then it is pushed into the body of the nerve itself, and a solution of quinine-urea injected into the nerve. This deadens all sensations in the region of the nerve.
Besides this, the use of heat is a well established form of treatment. In the old days, the best way to do this would be to have the patient lie down on his stomach and have his wife put a piece of flannel over the place where the pain was, and with a moderately hot iron, iron over the flannel until she had produced redness and relief. Nowadays electrical treatments by means of diathermy seem to be better than this old-fashioned treatment, perhaps because they are more mysterious.