Lumbar Sympathetic Block

A lumbar sympathetic block is an injection of medications into or around one or more sympathetic nerves in the low back. Sometimes, these nerves can transmit pain signals from peripheral tissues in the lower body to the central nervous system. The pain-relieving and anti-inflammatory medications contained in a lumbar sympathetic block can inhibit the ability of lumbar sympathetic nerves to transmit pain signals from the lower body.

Lumbar sympathetic nerves, which extend from both sides of the lumbar spine, belong to the sympathetic nervous system, which is involved in maintaining homeostasis. Sympathetic nerves begin as preganglionic neurons in the middle and lower regions of the spine. They synapse, or terminate, in a bundle of neurons called a ganglion, where they send their signals across a gap to a second group of neurons that travel to peripheral body tissues.

Injection of medications into lumbar sympathetic nerves may alleviate lower-body sympathetically mediated pain and other symptoms characteristic of sympathetically mediated conditions, such as swelling, numbness, skin discoloration, poor circulation and impaired mobility. Examples of such conditions include Reflex Sympathetic Dystrophy, Complex Regional Pain Syndrome and herpes zoster (shingles) affecting the lower limbs. Other conditions treated with this type of block are neuropathy and peripheral vascular disease.

The lumbar sympathetic block is an outpatient procedure that takes less than an hour to perform. The patient is given light sedation and the skin over the area to be injected is cleaned and numbed with local anesthetic. Using fluoroscopy (real-time x-ray) for guidance, the physician directs the injection into or around the target nerve. Then, after a short period of observation, the patient is released.

A successful lumbar sympathetic block is characterized by relief of pain and other symptoms of sympathetically mediated disorders. The duration of symptom relief varies between patients.

Since the block is impermanent, the patient will need another injection when symptoms return. The patient may also become a candidate for more complex treatments that quell pain and other symptoms over longer periods.

The lumbar sympathetic block:

• • Can provide relief of pain and other symptoms in sympathetically mediated disorders, which are often difficult to treat.
  • Can be conducted quickly, on an outpatient basis, due to the minimally invasive nature of the treatment.
• Involves very little, if any, recovery time.

Since a lumbar sympathetic block is a minimally invasive procedure, it is safer than more invasive interventions such as surgery. However, even minimally invasive procedures can produce complications. Some of the reported complications associated with this procedure include:

• Infection.
• Damage to surrounding tissues, such as blood vessels and spinal membranes.
• Temporary tenderness around the injection site.