What is an Epidural Block?
An epidural block or epidural spinal injection is a non-surgical treatment option for relieving back pain and other symptoms. It is not the same as epidural anesthesia given before birth to decrease labor pain.
Epidural blocks contain a strong anti-inflammatory agent called corticosteroid and an anesthetic for pain relief. It is administered into the epidural space of the spine, the space between the outermost covering of the spinal cord (dura mater) and the wall of the spinal canal. The epidural space is approximately 5 mm wide and is filled with spinal nerve roots, fat tissue and small blood vessels.
Indications of Epidural Blocks
Spine degenerative conditions such as herniated disc, spinal stenosis and many others may induce back pain due to the compression of the associated spinal nerves. The pain or numbness may extend to other parts of the body such as the hips, buttocks and legs. Your doctor first recommends non-surgical methods to treat back pain. Epidural blocks are one of these preferences.
An epidural spinal injection may be employed both for diagnostic and therapeutic reasons.
- Diagnostic: Helps determine the specific nerve root involved in the spinal problem
- Therapeutic: Induces short or long-term relief from pain and inflammation
Goal of Epidural Blocks
Epidural spinal injections are not a curative intervention, but a treatment tool to reduce discomfort so that rehabilitation programs such as physical therapy may be well executed. If no relief is obtained from an epidural block or other non-surgical methods, surgery may be recommended.
How are Epidural Blocks Administered?
Epidural blocks are usually administered on an outpatient basis. The procedure involves the following steps:
- You will be taken to the pre-op area where trained nursing staff check your vitals, review your medications and prepare you for the procedure. Blood sugar and coagulation status may also be evaluated if needed.
- You are then taken to the procedure room and will lie face down on a table.
- The injection site is cleaned and a local numbing agent administered so that you don’t feel pain during the procedure.
- A thin hollow needle is then inserted into the epidural space, guided by fluoroscopic X-ray to place the needle in the correct position. This system gives real time X-ray images of the position of the needle in the spine on a monitor for your surgeon to view.
- A contrast material is then injected through the properly placed hollow needle to confirm that the drug flows to the affected nerve when injected.
- When your doctor is satisfied with the position of the needle, the anesthetic drug and corticosteroid are injected through the same needle inserted in the spine.
- Finally, the needle is removed and the injection site covered with a dry, sterile bandage.
It takes about 15-30 minutes to complete.
What will I Experience Following an Epidural Block?
You may feel some pressure during the injection but the procedure is mostly painless. You will feel numbness in the arms or legs just after the procedure due to the anesthetic component. This usually wears off within 1-8 hours, following which you may feel some back pain. The steroid component of the epidural block takes about 24-72 hours before showing its pain-relieving action.
In some cases, if the desired effect is not obtained reinjection may be recommended. The standard guidelines for steroid injections state a maximum of 3 injections per year. In case no relief is obtained from spinal injection, then surgery is considered.
Post-procedure Instructions Following Epidural Blocks
After the procedure, you should not drive or go back to work. You should rest and avoid any vigorous activities. Your doctor may give specific post-care instructions. Please follow the instructions for a faster recovery.
Risks and Complications Associated with an Epidural Block
As with any procedure, epidural blocks may be associated with certain complications such as:
- Bleeding or infection at the injection site
- Pain during or after injection
- Post-injection headache
- Nerve injury
- Bladder dysfunction
- Fluid retention
- Respiratory arrest
- Epidural hematoma
- Spinal cord infarction
Discuss with your doctor if you have any concerns prior to the procedure.