Lumbar Sympathetic Block

A lumbar sympathetic block is an injection of local anesthetic around a group of nerves in your lower back (see figure below). It may be done if you have Reflex Sympathetic Dystrophy, (RSD), a disease involving a disturbance of circulation to the skin or neuropathic pain (pain caused by a disorder of the nervous system) , Sympathetically Maintained Pain, Complex Regional Pain Syndrome, and Herpes Zoster (shingles) involving a single extremity or head and face.

The injection tp block the sympathetic nerve signals consists of a local anesthetic (like lidocaine or bupivacaine) and epinephrine (adrenaline) to prolong the effects of the injection. The injection may in turn reduce pain, swelling, color, and sweating changes in the lower extremity and may improve mobility. Immediately after the injection, you may feel your lower extremity getting warm. In addition, you may notice that your pain may be gone or quite less. The local anesthetic wears off in a few hours. However, the blockade of sympathetic nerves may last for many more hours. Usually, the duration of relief gets longer after each injection. If you respond to the first injection, you will be recommended for repeat injections. Usually, a series of such injections is needed to treat the problem. Some may need only 2 to 4 and some may need more. The response to such injections varies from patient to patient.

It is very difficult to predict if the injection(s) will indeed help you or not. The patients who present early during their illness tend to respond better than those who have this treatment after about six months of symptoms do. Patients in the advanced stages of disease may not respond adequately.