Often a group of nerves, called a plexus or ganglion, that causes pain to a specific organ or body region can be blocked with the injection of medication into a specific area of the body. The injection of this nerve-numbing substance is called a nerve block.
There are different kinds of nerve blocks used for various purposes.
Therapeutic nerve blocks are used to treat painful conditions. Such nerve blocks contain local anesthetic that can be used to control acute pain.
Diagnostic nerve blocks are used to determine sources of pain. These blocks typically contain an anesthetic with a known duration of relief.
Prognostic nerve blocks predict the outcomes of given treatments. For example, a nerve block may be performed to determine if more permanent treatments (such as surgery) would be successful in treating pain.
Preemptive nerve blocks are meant to prevent subsequent pain from a procedure that can cause problems including phantom limb pain.
Nerve blocks can be used, in some cases, to avoid surgery.
Types of Nerve Blocks
Various areas of pain require different nerve block types. Below are a few of the available nerve blocks and some parts of the body where they are used.
Sympathetic nerve block: A sympathetic nerve block is one that is performed to determine if there is damage to the sympathetic nerve chain. This is a network of nerves extending the length of the spine. These nerves control some of the involuntary functions of the body, such as opening and narrowing blood vessels.
Stellate ganglion block: This is a type of sympathetic nerve block performed to determine if there is damage to the sympathetic nerve chain supplying the head, neck, chest, or arms and if it is the source of pain in those areas. Although used mainly as a diagnostic block, the stellate ganglion block may provide pain relief in excess of the duration of the anesthetic.
Facet joint block: Also known as a zygapophysial joint block, the facet joint block is performed to determine whether a facet joint is a source of pain. Facet joints are located on the back of the spine, where one vertebra slightly overlaps another. These joints guide and restrict the spines movement.