Epidural steroid injections are a common treatment option for many forms of lumbar pain and irradiating leg pain.
Epidural steroid injections are a common treatment option for many forms of lumbar pain and irradiating leg pain. This type of treatment was first used in 1952 and is still an integral part of non-surgical treatment for sciatica and low back pain. Sometimes a single epidural injection is enough to get rid of pain, but quite often drug therapy is used in conjunction with a comprehensive rehabilitation program, to achieve optimal results.
Most doctors would agree that the effectiveness of the injection is usually temporary, providing relief from pain for one week to one year. At the same time, an epidural injection can be very helpful in relieving acute low back pain and/or leg pain. It is important to note that the injection can provide sufficient pain relief to allow the patient to begin a rehabilitation program more quickly, particularly exercise. If the injection is used for the first time, its effectiveness may be longer from three months to one year.
It should be noted that epidural steroid injections are performed not only in the lumbosacral spine, but they are also quite often used to relieve pain in the neck and thoracic region.
Effectiveness of epidural injections
Many studies suggest short-term benefits of epidural steroid injection. As for data on the long-term effectiveness of epidural steroid injections for lumbar pain, the issue continues to be a matter of debate. This is exacerbated by the lack of properly conducted studies.
For example, many studies do not include the mandatory use of radiological control (fluoroscope) of the injection itself, which allows you to check the correctness of the drug administration. In addition, many studies do not classify patients according to their diagnosis, which makes it impossible to clearly trace the effectiveness of the treatment method for various spinal pathologies that are symptomatic with low back pain.These methodological shortcomings tend to make it difficult or nearly impossible to assess treatment outcomes.
Despite this, most studies indicate that in more than 50% of patients, the use of an epidural steroid injection has a pain-relieving effect and resolves the problem. Researchers also emphasize that the effectiveness of the procedure largely depends on the professionalism of the doctor performing the manipulation, as well as the need to always use fluoroscopy to ensure accurate needle placement.
Epidural steroid injections under radiological control allow the drug to be injected directly (or very close) to the source of pain generation. In contrast, oral steroids and analgesics get to the site of pain in low concentrations and have a less focused effect, which subsequently can manifest as side effects.
Since the vast majority of pain is caused by inflammation, an epidural injection can help control local inflammation by helping to “flush out” the chemical components that cause inflammation (proteins and chemicals) in the affected area that exacerbate pain.
Epidural injection procedure
The epidural injection procedure usually takes 15 to 30 minutes and follows a standard protocol:
- The patient lies on a table with a small pillow under the abdomen. If this position causes pain, the patient may be allowed to sit or lie on his side in a slightly bent position.
- The skin area in the lumbar region is treated with an antiseptic and then anesthetized with a local anesthetic.
- Under radiological control the needle is inserted under the skin and guided into the epidural space. Radiography ensures accurate insertion of the needle into the desired location in the epidural space. As studies have shown, in many (>30%) cases, when an epidural injection is performed without X-ray control, the treatment results have been negative.
- Once the needle is in the correct position, contrast is injected to confirm the position of the needle site. A solution of hormone and local anesthetic is then injected into the epidural space. Although the steroid solution is injected slowly, most patients feel some pressure and discomfort due to the amount of solution used (which can range from 3 to 10 ml when injected).
- After the injection, the patient is monitored by the doctor for 10-20 minutes before being discharged home.
During the procedure, sedatives may be used to ensure patient comfort. However, sedation is rarely necessary because epidural injections usually do not cause significant discomfort. If sedation is still used, some precautions must be observed, including that the patient should not eat or drink for several hours before the procedure. The patient should be instructed by a physician for specific instructions before the procedure.
Pain at the needle insertion site may persist for several hours after the procedure. If pain persists in the injection site, the injection site may be treated with ice for 10 to 15 minutes once or twice an hour. In addition, patients are usually advised to observe rest and rest for the remainder of the day after the procedure. Normal activities can usually be resumed the next day.Temporary soreness may persist for several days after injection due to fluid pressure trapped in the area of the procedure or because of localized chemical irritation.
The patient should also consult a physician about whether pain medications (or some other medications) can be taken on the day of the injection.
How an epidural block works
Epidural injection delivers a hormonal drug directly into the epidural space of the spine. Most often additional components, local anesthetics, are used.
The epidural space contains epidural fat and small blood vessels, and surrounds the dural sac. The dural sac holds the spinal cord, nerve roots, and cerebrospinal fluid (the fluid in which the nerve roots are located).
The injection usually uses a solution containing a hormone (cortisone) with a local anesthetic (lidocaine or bupivacaine) and/or a saline solution.
- The hormone is usually administered as an anti-inflammatory agent. Inflammation is a common component of the manifestation of lumbar pain. The hormone reduces the inflammation and thus helps to reduce the pain. Triamcinolone acetonide, dexamethasone, methylprednisolone acetate, and betamethasone are used as major steroid drugs.
- Lidocaine is a fast-acting local anesthetic that is used for temporary pain relief. Bupivacaine may also be used.
- Saline solution is used to dilute the local anesthetic or as a “flushing” agent to dilute chemical or immunologic agents that contribute to inflammation.
Epidural injections are often used to treat radicular pain, also called sciatica (pain that comes from a pinched nerve in the lumbar spine, radiating to the back of the leg or to the foot).
Inflammatory mediators (e.g., the substance PLA2, arachidonic acid, TNF-α, IL-1, and prostaglandin E2) and immune mediators can generate pain and related back problems such as herniated disc or facet arthritis. These conditions, and many others, cause inflammation, which in turn can cause significant nerve root irritation, swelling and soreness.
Hormones suppress inflammatory responses caused by chemical and mechanical sources of pain. They also reduce the immune system’s ability to respond to inflammation associated with nerve or tissue damage. The body’s typical immune response is the production of white blood cells and chemicals to protect it from infections and foreign substances such as bacteria and viruses. Inhibiting the immune response with an epidural steroid injection can reduce the pain associated with inflammation.