The epidural space lies just outside the special covering or dura, which encloses the spinal canal. An 'epidural' is a type of regional anesthetic in which a needle is positioned between the bones of the spine to allow the anesthesiologist to insert a small plastic tube (or catheter) into the epidural space. The needle is then removed and local anesthetic is injected through the catheter. This local anesthetic moves (or diffuses) across the dura. into the spinal canal, and temporarily stops the spinal nerves from working, so that sensation and movement in the area supplied by the nerves does not occur. When the effect of the local anesthetic wears off, sensation and movement will return. If a weaker solution of local anesthetic is used, then only painful sensations will be blocked.
This is very useful for controlling pain and is called epidural analgesia. Often continuous infusions of local anesthetic solutions are used, which allows the effect to be maintained as long as required. The catheter may be placed in the upper back (thoracic spine) or the lower back (lumbar spine), depending on where the effect is needed. This is a very useful and safe procedure, when performed with appropriate care by an experienced anesthesiologist.
The benefits from the first shot only lasted 2 weeks. The second and third set of injections lasted about 90 days. In November, I was ready to have surgery. My EMG and nerve conduction tests proved that the nerves were "sleeping" before I was. After another MRI, the neurosurgeon said I was a candidate for surgery but I was not able to get the endoscopic type surgery that is less invasive. I would have an incision about 6-8" long. Along with removing the herniation, they would have to increase the size of the hole where the nerve roots were going through.
The lumbar puncture procedure was taken to the United States by Arthur H. Wentworth an assistant professor at the Harvard Medical School , based at Children's Hospital . In 1893 he published a long paper on diagnosing cerebrospinal meningitis by examining spinal fluid.  However, he was criticized by antivivisectionists for having obtained spinal fluid from children. He was acquitted, but, nevertheless, he was uninvited from the then forming Johns Hopkins School of Medicine , where he would have been the first professor of pediatrics . [ citation needed ]