Types of Interventional Pain Management
Epidural Steroid Injection (ESI)
An ESI is a common type of injection that is given to provide relief from certain types of low back and neck pain. The “epidural space” is the space between the covering of the spinal cord (dura mater) and the
inside of the bony spinal canal. It runs the entire length of your spine. When injected into this area the medication moves freely up and down the spine to coat the nerve roots and the outside lining of the facet joints near the area of injection. For example, if the injection is given in the lumbar spine, the medication will usually affect the entire lower portion of the spine.The epidural needle is inserted into the back until the doctor feels sure it is in the epidural space. The doctor will then place a small amount of lidocaine into the epidural space and wait to see if you feel warmth and numbness in your legs. If so, the needle is most likely in the correct position. The remainder of the medication is injected and the needle is withdrawn.
There are three different ways to perform an epidural injection:
transforaminal/selective nerve root block
A caudal block is placed through the sacral gap
(a space below the lumbar spine near the sacrum).
The injection is placed into the epidural space.
This type of block usually affects the spinal nerves at
the end of the spinal canal near the sacrum. This
collection of nerves is called the cauda equina.
One of the benefits of this type of injection is less chance of puncturing the dura.
The interlaminar approach is the most common way of performing an epidural injection. This type of injection is performed by placing a needle between two vertebrae from the back. The needle is inserted
between the spinous processes of two vertebrae. You can actually feel the bumps that make up the spinous process by feeling along the back of your spine.
Transforaminal/Selective Nerve Root Block (SNRB)
The transforaminal approach is a very selective injection
around a specific nerve root. The foraminae are small
openings between your vertebrae through which the
nerve roots exit the spinal canal and enter the body.
By injecting medication around a specific nerve root,
the doctor can determine if this nerve root is causing
the problem. This type of epidural injection is used most
often for diagnostic purposes, and may also be performed
in the neck or lower back.
Facet Joint Injections
Facet joint injections are used to localize and treat low back pain caused by problems of the facet joints. These joints are located on each side of the vertebrae. They join the vertebrae together and allow the spine to move with flexibility. The facet joint injections form a pain block that allows the doctor to confirm that a facet joint is causing the pain. The medication used also decreases inflammation that occurs in the joint from arthritis and joint degeneration.It is important to make sure that the injection goes directly into the facet joint. Fluoroscopy can be used to confirm that the needle is in the right position before any medication is injected. A fluoroscope uses X-rays to show a TV image. You doctor can watch on the screen as the needle is placed into the joint and magnify the image to increase accuracy. There are two types of facet joint injections.
Intra-articular are injected directly into the joint to block the pain and reduce inflammation.
Medial branch nerve blocks help determine whether the joint is indeed a source of pain by blocking the
small nerves that connect with the joint.Specific Indications A facet joint injection is perhaps the best way to diagnose facet joint syndrome. Joints that look abnormal on an X-ray may in fact be painless, while joints that look fine may actually be a source of pain. This is a rather simple procedure with little risk.
Radiofrequency (RF) lesioning is considered to be a safe, proven way of treating chronic facet joint pain. It is generally indicated for individuals who have had spinal pain for at least 3 months and the source of the pain has been determined to be the facet joint, usually by performing medial branch blocks (see above). Under X-ray guidance, the doctor will then place a small needle near the tiny nerves which innervate the facet joints causing the pain. A small electrode is inserted through the needle to lesion the specific nerve. Very light electrical stimulation will be performed to confirm the exact location.
SI Joint Injections
Sacroiliac (SI) joint pain is easily confused with back pain
from the spine. The SI joint is located between the sacrum
and pelvic bones. Sometimes injecting the SI joint with
lidocaine may help your doctor determine whether the
SI joint is the source of your pain. If the joint is injected
and your pain does not go away, it is probably coming
from somewhere else. If the pain goes away immediately,
your doctor may also inject cortisone into the joint before
removing the needle. Cortisone is added to treat inflammation
from SI joint arthritis. The injection usually gives temporary relief for several weeks or months.
SI joint injections can be used both to treat pain and to determine the source of the pain. This injection usually requires the use of fluoroscopic guidance or a CT scan in order to make sure the needle is placed correctly in the joint.
Differential Upper and Lower Extremity Injections
Various types of injections into certain areas of the upper and lower extremities can help your doctor
decide where the pain is starting. Pain that comes from problems with the back and the spinal nerves can mimic many other conditions. Sometimes it is impossible to tell if the pain you are experiencing is due to a back or neck condition or a problem in your shoulder, elbow, wrist, hip, knee, or foot.
To help determine whether a joint of your lower limb is causing you pain, your doctor may suggest
injecting medication, such as lidocaine, into the joint to numb the area. Once the medication is injected, if the pain goes away immediately, that joint is more likely to be the source of the pain than your back. Your doctor can then focus on finding the problem in the joint.
Proliferative therapy, also know as prolotherapy, is a method of injecting an anesthetic and an irritant(usually containing dextrose and fish oil) into joints, ligaments or tendons that are weakened, torn or pulled. It is a non-surgical method by which ligaments and tendons are repaired, resulting in strengthening of the weakened connective tissue by using the body’s own healing powers.
It is important to understand that the purpose of this treatment is to strengthen these weakened areas, and not to decrease pain. The decrease in pain usually results from the increased stabilization and ability for the muscles to relax. Prolotherapy is useful in the treatment of:
Ligament or tendon dysfunction (sprain, strain, and tendonitis)
Myofascial Trigger Point Injections
Trigger point is a localized, irritable, taut band of muscle that has become a source of considerable pain because it will not relax. When a trigger point is pressed, it will feel sore in the area and can also refer pain over to another part of the body.Trigger points can develop as a result of:
Traumatic injury to the muscle
Strain due to repetitive use
Spine conditions (herniated disc)
Trigger points will eventually affect mobility and posture and will compromise normal movement
patterns, leading to soft tissue dysfunction as well as more trigger points, intensifying the pain pattern and dysfunction.
Injecting a trigger point with anesthetic, saline, or a corticosteroid can relax the muscle and help to eliminate the trigger point. Relaxing the muscle improves blood flow and healing. Without the injection, a trigger point can lead to the development of other trigger points.
What is the procedure like?
We will insert a small needle into your trigger point that will deliver a local anesthetic. You may feel a sharp pain during the injection and you may also feel the muscle jump or “grab.” Usually, right after the trigger point is injected there is a significant decrease in pain and often less stiffness in the muscles.
You may also experience some numbness over the pattern of referral of the muscle injected for about an hour after the injection. There may be some stiffness and soreness, which should not last longer than 24hours. Within two or three days you should experience a significant decrease in pain.General Contraindications
When certain medical conditions are present, doctors may determine it is unsafe to perform a spinal
injection. Your doctor will discuss any concerns with you before making a final decision.
If you have a tendency to heavy bleeding or are on anti-coagulant therapy (medication that prevents blood clotting), you are not a good candidate for spinal injections. The physician might ask you to stop all medications such as aspirin and ibuprofen five days before the injection. These medications can decrease the ability of the blood to clot and lead to problems. Make sure your provider has a list of your medications well ahead of your scheduled procedure.
If you have a local or systemic infection, a spinal injection may put you at greater risk for spreading the infection into the spine, causing meningitis (inflammation in the covering that surrounds the spinal cord).
Make sure to tell your health care provider if you have any infected wounds, boils, or rashes anywhere on your body.
Unstable Medical Conditions
Injections are usually an elective procedure offered to patients without life-threatening conditions. A medically unstable patient should have his or her medical condition treated before any elective injections are given.
General Precautions for Injections
Consider these basic warnings before choosing to have a spinal injection.
If you are chronically taking a platelet-inhibiting drug, such as aspirin or NSAIDs (non-steroidal anti-inflammatory drugs), you have an increased risk of bleeding and might not be a candidate for a spinal injection.
If you are hypersensitive or have certain allergies to medications, you may have a negative reaction to the drugs used in the injection. Make sure to give your provider a list of your allergies.
If you have an accompanying medical illness, you should discuss the risks of spinal injections with your physician. For instance, patients with diabetes mellitus might experience an increase in blood sugar after an injection with cortisone. Patients with congestive heart failure, renal failure, hypertension, or a significant cardiac disease may have problems due to the effects of fluid retention several days after an injection.