Selective Nerve Root Block
Lumbar Selective Nerve Root Block - Nerve Pain in the Back
A lumbar selective nerve root block is used to diagnose and in some cases, treat nerve pain in the back. A variety of conditions can affect the nerves in the back, which not only can cause pain in the back, but pain that spreads to the legs and feet. A lumbar selective nerve root block places medication directly around a suspected nerve to help determine if it is the source of pain. If the selective nerve root block relieves the pain, then the doctor can proceed with treatment, which may include additional medication injections or surgery.
The lumbar area of your spine is located in your lower back. Five small bones (vertebrae) make up the lumbar spine. A disc between each bone allows movement, provides stability, and acts as a shock absorber. The opening in the center of each bone forms the spinal canal.
Your spinal cord is located within the protective spinal canal. The spinal cord extends from the brain and is a major part of your nervous system. The spinal cord does not fill the entire space in the spinal canal. Instead, the spinal cord is surrounded by the epidural space (cavity), which contains tissue, nerves, and blood vessels.
Spinal nerves extending from the spinal cord travel out of openings or “tunnels” in the bones (foramina) to exchange nerve signals with your brain about specific parts of your body. The five nerves at the lumbar level control bowel and bladder function, as well as muscles and sensation for your lower body, including buttocks, legs, and feet.
A lumbar selective nerve root block is used to identify if a particular spinal nerve root is the source of pain. Ruptured (herniated) discs and spinal nerve root diseases (radiculopathy) can contribute to pinched or compressed nerves and lead to pain. Another possible cause, spinal stenosis, is a condition that causes the spinal canal to narrow and put pressure on the spinal cord and nerves.
The symptoms that you experience depend on the cause of your back pain. Pinched nerves in the lumbar spine can cause back pain, tingling, and numbness that radiates to the buttocks, legs, and feet. The pain may become worse when you move your back, cough, or laugh. Your back muscles may spasm. Your legs may feel weak.
Your doctor will examine you and conduct tests to determine the cause of your back pain. Imaging tests, lab tests, and nerve studies may be used to provide your doctor with more information. A lumbar selective nerve root block is used to determine if a specific nerve is the source of pain. In addition to being a diagnostic tool, a lumbar selective nerve root block can help temporarily relieve pain.
A lumbar selective nerve root block uses an injection to place medicine directly around a suspected nerve. A local anesthetic medication is used to “turn off” the nerve, stopping its ability to send pain signals. Steroid medication may be added to help decrease nerve inflammation.
A lumbar selective nerve root block is an outpatient procedure. You will wear a gown for the procedure and be positioned sitting up or lying on your side or stomach. Before you receive the selective nerve root block, the lower part of your back will be sterilized and numbed with an anesthetic. You will receive relaxation medicine before your procedure.
Your doctor will use a live X-ray image (fluoroscopy) to carefully insert and guide the needle to the foraminal space “tunnel” of the suspected spinal nerve. A contrast dye is used to confirm the needle placement. Next, the medication is injected around the nerve, and the needle is removed.
You will be monitored for several minutes before you can return home. You should have another person drive you home because you received sedation medication. Your doctor will instruct you on how to relieve temporary pain at the injection site. You will be asked to keep track of your pain over the next several days.
If the lumbar selective nerve root block relieved your pain, then the suspected nerve was the source of the problem. Your doctor may repeat the injections as a form of treatment or discuss surgery if necessary. If the lumbar selective nerve root block did not relieve your pain, the process may be repeated at a different nerve to help determine the source of the problem.