Selective Nerve Root Blocks

Nerve roots exit the spinal cord and form nerves that travel into the arms and legs. These are the nerves that allow you to move your legs, arms, and chest. These nerves may become compressed or injured as a consequence of herniated discs, stenosis (spinal nerves are compressed) or injuries, resulting in pain and inflammation. Nerve roots are attached to the spinal cord. One exits each side of the spine at every vertebral level. These nerves carry signals throughout the body from the skin to the muscles. When one of the nerve roots is irritated, patients may have pain, numbness, tingling, and weakness down an arm or leg. Selective nerve root block, or SNRB, is a procedure used for both diagnostic (to obtain whether a specific spinal nerve root is the source of pain) and therapeutic (to reduce inflammation, thus relieving or reducing pain) purposes. A selective nerve root block may be performed in any area of the spine, (cervical, thoracic, and lumbar). Selective nerve root blocks are performed under fluoroscopic guidance. A needle is inserted into the epidural space in the foramen of the suspected spinal level, and medications such as, a local anesthetic and/or steroids are injected to bathe the nerve root. If a patient’s pain improves, that nerve is likely the cause of pain. Although a lumbar epidural steroid injection may produce the same effect, a SNRB is a more focused injection that has a better diagnostic value than an epidural steroid injection, especially in surgical planning. It provides information allowing for proper treatment, which may include additional nerve blocks or surgery at a specific level.