What are Facet Joint Injections And Medial Branch Blocks?

 Facet joint injections and medial branch blocks explained by Denver, Golden, Aurora, Boulder, Broomfield, Jefferson, and Littleton Colorado’s top pain doctors

In general, patients who are referred for facet joint injections have exhibited symptoms of a degeneration of the facet joint. This degeneration can be linked with a number of conditions, such as lumbar facet syndrome. It has been estimated that approximately two-thirds of all adults will experience difficulties associated with back or neck pain at some point in their lives. Indeed, the most common form of pain for people in the U.S. has been reported to be chronic spine pain. The primary goal of both facet joint injections and medial branch blocks is to provide patients with relief from these forms of pain. In fact, facet joint injections and medial branch blocks have been regarded as being a key feature in the conservative pain management treatment plan for treating lower back and neck pain.

Not only are facet joint injections and medial branch blocks beneficial in terms of their analgesic properties, they also assist physicians with a more accurate identification of the source for the patient’s pain. Using image-guided techniques for proper placement of the needle, physicians inject a solution of corticosteroid medication and local anesthetics. This solution is believed to reduce inflammation within the facet joint area. This reduction in inflammation thereby provides confirmation that the area surrounding the facet joint is likely the cause for the patient’s pain and discomfort.

Once the source of the pain is identified through either the facet joint injection or medial branch block, physicians and patients are able to make more informed decisions with regard to ongoing pain management planning. Moreover, successful facet joint injections and medial branch blocks are expected to improve an individual’s ability to function, thus, may provide some patients with significant improvements in their overall quality of life. These treatments have also been shown to be beneficial in preventing premature or unwarranted invasive back surgery.

There are a number of conditions that can be successfully treated using facet joint injections or medial branch blocks. For instance, pain in the facet joint area can commonly be caused by either injury or trauma. Additionally, arthritis has also been shown to benefit from facet joint injections, as the condition is the result of a degeneration of the facet joint through the gradual loss of synovial fluid. Arthritis is generally found to occur frequently among populations of older adults, though individuals at any age may become afflicted with pain and discomfort associates with this condition. Finally, many have linked poor posture or genetic spinal abnormalities to symptoms of chronic back and neck pain.

Facet Joint Anatomy

Also known as the zygaphphysial joint, the facet joint can be found in the lower back at the back of the spinal column. Facet joints can also be found on either side of the vertebra located within the neck. Facet joints are what allow an individual to bend and twist at the waist. Further, facet joints can provide some degree of stability within the trunk. These joints are comprised of bony tissue formed in the shape of small knobs, and a thin layer of cartilage separates the joint itself. As with many other joints within the body, there is a capsule surrounding the facet joint that contains a lubricating fluid called synovial fluid. The purpose of this fluid is to assist with reducing the amount of friction between the bones of the joint and to provide some degree of protection. This area is also known as the synovial area, and degenerative changes in this area can result in difficulties with chronic pain and discomfort. Overtime, degeneration within the synovial facet joint area can lead to a decrease in mobility and ongoing difficulties with pain. The anatomy of the facet joint, however, can help delineate the underlying function of facet joint injections and medial branch blocks, and how they can provide relief from chronic pain in these regions.

What is a Facet Joint Injection?

Facet Joint Injection ProcedureFacet joint injections have generally been used to treat both cervical pain (i.e., neck pain) and lumbar pain (i.e., back pain) associated with a number of conditions. First described over 50 years ago for the treatment of back pain, facet joint injections are nerve root blocks. They are nonsurgical, thus have been regarded as a conservative approach for treating pain within the lower back. Previous studies have suggested that nearly half of all reported instances of neck and back pain can be attributed to the facet joint area.

Patients undergoing a facet joint injection procedure will be prepped for the injection by having the area thoroughly cleaned. A topical anesthetic may be used in order to reduce the discomfort associated with the injection needle. The physician will then inject a solution of corticosteroid, such as dexamethasome, and a local anesthetic, typically lidocaine, bupivacaine, or mepivacaine. This injection is made in the facet joint itself, in order to reduce the degree of inflammation within the area, thereby reducing the associated pain.

To aid in determining the source of pain, lumbar and cervical facet blocks are also commonly used as a diagnostic tool. More specifically, if the degree of reported pain is reduced following the procedure, it can be assumed that the inflammation in that area was the primary source.

Literature examining the effectiveness of facet joint injections has generally supported their use in diagnosing and relieving chronic pain. One particular study examined back pain patients who were between the ages of 20 and 70 years of age. Patients received a facet joint injection containing a solution of the local anesthetic, bupivacaine, and the steroid, methylprednisolone. At a three-month follow-up examination, almost three-quarters of the patients had reported immediate relief from pain. Moreover, 19% of patients had reported that they experienced compete relief from pain. It was concluded from these findings that facet joint injections are a useful treatment alternative to either back or neck surgery.

What Is A Medial Branch Block?

Facet Joint InjectionRegarded as effective for treating pain that originates within the facet joint of the spine, medial branch blocks utilize corticosteroids, such as dexamethasome, in their function as an analgesic. During most procedures, a local anesthetic, such as lidocaine, bupivavaine, or mepivacaine, is also used. The medial branch block targets the medial branch nerves, which are known to provide sensory information to the facet joint. More specifically, there are two medial nerves that connect to each facet joint. These nerves provide motor control and sensory feedback to the small muscles in the back and neck regions. In terms of the cervical, or neck area, these medial branch nerves can be found within the bony groove of the neck or in the lower back area. The nerves in the lower back region are also known as lumbrosacral medial branch nerves. Within the upper back area are the thoracic medial branch nerves.

During the medial branch block procedure, a needle is inserted directly into the nerve. This needle then injects the solution of medication in order to provide relief from inflammation and pain. Support has been found for medial branch blocks to be as safe and effective as both back and neck pain. Moreover, medial branch blocks can even aid in the prevention of surgery.

Previous studies have suggested that between 10-15% of patients suffering from chronic lumbar pain also exhibit inflammation and degeneration within the facet joint that is likely to account for the patient’s pain and discomfort. Thus, lumbar medial branch blocks are ideal for treating this population of patients as the intervention targets the nerves within the facet joint themselves. Similarly, cervical branch blocks provide relief from upper back and neck pain, as well as headaches, owing to damage or irritation within the cervical area.

As with facet joint injections, medial branch blocks can be used in diagnostic decision-making. Should the patient’s pain and inflammation remit following the injection, the facet joint then is most likely to be the cause. This may also aid in treatment planning. Physicians may use information garnered from the injection to plan for physical therapy recommendations, future injection procedures, or even performing a radiofrequency facet ablation.

How Are Facet Joint Injections Performed?

To prep for a facet joint injection, patients are first positioned lying face down on an X-ray table. The skin in the area of the injection site is then thoroughly cleaned and sterilized. Should the patient have opted for the use of sedation (generally to ensure that the patient is comfortable during the procedure), they are given the sedation medication through an IV and their vital signs (heart rate, respiration, and blood pressure) are closely monitored during the entire procedure.

The area around the injection site is then anesthetized and an X-ray device, known as a fluoroscopy, is used to assist the physician with proper needle placement. During placement, a dye may also be injected that can be seen through the X-ray device. This can further assist the physician with proper needle placement. Once the physician has placed the injection needle in the proper location, the anesthetic and cortisone solution is inserted. The entire procedure lasts approximately 15 minutes and can be done in an outpatient setting.

In general, facet joint injections are conducted as a way to locate and treat joint pain. Diagnosis confirmation can be made through successful facet joint injections. Indeed, a controlled trial, examining patients with complaints of lumbar pain, revealed that between 42% and 92% of reported reductions in subjective pain within four weeks of undergoing a facet joint injection can be attributable to the procedure. Further, other studies have corroborated these findings, as well as have supported the use of facet joint injections in the prevention of premature or unwarranted surgery.

Though facet joint injections are minimally invasive, there are some risks associated with the procedure. In general, these risks are mild (such as minor bleeding at the injection site) and disappear within a few hours or days. Many patients report a mild soreness at the site of the injection also. This soreness generally disappears within a week of the procedure and may be treated with over-the-counter pain relievers should the patient experience discomfort. More serious complications may occur, though this is quite rare. These complications include headaches, bleeding, infection, allergic reactions, and nerve damage.

Technical errors owing to the procedure itself can also lead to potential complications. For instance, the performing physician may misplace the needle. Given that physicians use a fluoroscopic device or ultrasound device, along with contrast dye, to ensure the proper placement of the needle, this complication is quite rare. Other side effects following facet joint injections are generally associated with individual reactions to the corticosteroid medication or other medications used during the procedure. These include facial flushing (known as the steroid flush), elevated blood sugar, weight gain, and insomnia. Patients are encouraged to talk with their doctor about any history of reaction to medications or known allergies. Finally, the use of local anesthetics has been shown to cause a gradual desensitization of the nerve over time in a small group of patients.

How Are Medial Branch Blocks Performed?

The procedure for medial branch blocks is similar to that of the facet joint injection. First, the patient is instructed to lie down on an X-ray table. The skin in the area of the injection is cleaned and thoroughly sterilized. Should the patient opt for sedation, the sedation medication is delivered using an IV and the patient’s vital signs (heart rate, respiration, and blood pressure) are closely monitored during the entire procedure. In most cases, a topical anesthetic is applied to the skin to avoid any discomfort from the injection itself.

Proper needle placement is ensured in much the same way as the facet joint injection. Contrast dye and fluoroscopy assists the physician with guiding the needle into the proper location. Once the needle is in place, the physician will inject a solution of anesthetic and corticosteroid medication into the facet area. Generally, patients will experience minor bleeding at the site of the injection, thus a band-aide is applied to the area. The entire procedure generally takes approximately 15 minutes. Prior to discharging the patient, they are monitored for approximately 30 minutes. This is to ensure that the patient does not experience any adverse side effects as a result of the injection. Patients typically report experiencing immediate or nearly immediate relief from their symptoms of pain and discomfort.

Most risks associated with this procedure relate to technical errors, in particular, improper needle placement. Though very rare, accidental insertion of the needle into a blood vessel may occur in medial branch blocks within the neck or upper back (occurring in only 3% of patients). This is typically avoided with the use of technology to ensure proper placement. Infection, bleeding, and nerve damage are other potential risks associated with medial branch blocks.

The medial branch block itself is also associated with potential side effects. These are similar to facet joint injections and include elevated blood sugar, arthritis, stomach ulceration, weight gain, and a reduction in immune response. Further, local anesthetics have been associated with a gradual desensitization of the nerve. Although very rare, temporary neurological symptoms have been associated with the use of local anesthetics (occurring in less than 2% of patients). These symptoms may include chest pain or discomfort or nausea. It is recommended that patients speak with their physician about the risks associated with medial branch blocks when considering this treatment option.

Preparation For The Procedures

In preparation for the facet joint injection procedure, patients are generally instructed to discontinue their current medication regime, which includes the use of non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen. The reason for this is that it reduces the risk of bleeding during and after the facet joint injection procedure. Patients are not allowed to eat or drink anything for a specified period of time prior to the procedure. Patients are instructed to arrange for transportation following the procedure, as it is not recommended that patients drive afterwards. Patients will generally be seen for a follow-up evaluation to assess the patient’s degree of pain and discomfort and to make any other follow-up recommendations.

Conditions Related To Facet Joint Injections And Medial Branch Blocks

Neck Pain - Facet JointsWhile there are a number of conditions that have been identified as being the source of back and neck pain, in some cases the source may not be identified. Indeed, back and neck pain can often been quite difficult to diagnose given the variation between individuals and the number of possible conditions. Currently, there are a number of techniques that can assist physicians with diagnosing the source of a patient’s pain. Typically, physicians utilize imaging studies, such as an X-ray device or an MRI, in order to identify spinal abnormalities. Additionally, facet joint injections and medial branch blocks can be used diagnostically. Thus, should the injections effectively identify the source of the pain and inflammation, the therapeutic procedure can then be scheduled. Nonetheless, it may be necessary for physicians to perform additional examinations to properly diagnose the patient’s pain condition.

In general, patients suffering from lumbar facet pain generally report complaints of pain in the lower back, hips, or buttock region. In contrast, patients suffering from neck facet pain generally describe that their neck muscles will spasm and that they experience headaches. In both lumbar facet pain and cervical facet pain, it is not uncommon for the symptoms of pain and discomfort to worsen with movement.

Facet joint injections and medial branch blocks can be employed to treat a wide variety of conditions. As such, one goal of the assessment process is to rule out any other conditions that may be potential sources of pain. These may include degenerative disc disease, herniated disc disease, spondylolysis, and spinal stenosis. However, most facet joint injections and medial branch blocks are performed on patients who have primary symptoms of facet syndrome.

Facet Syndrome

Patients who have been referred for medial branch blocks typically exhibit symptoms of facet degeneration owing to facet syndrome. The facet joint provides flexibility at the waist, as well as stability in the back during movement. They are approximately the size of a thumbnail and can be found in between the vertebrae of the spine. A thin layer of cartilage generally separates the facet joints and a sac of lubricating synovial fluid encapsulates the entire joint. The nerves within the joint are known as medial branch nerves and transmit pain information to the brain.

Facet joints are very active. Thus, they experience physical stress on a constant basis. As the individual ages, the protective cartilage begins to weaken and degenerate. This can lead to painful bone spurs that may emerge on the edge of the facet joint. This degeneration and damage can cause significant inflammation, pain, tenderness, and joint stiffness.

Typically, facet joint syndrome is the result of a natural aging process, though it may also occur as the result of injury or overuse during childhood. Other risk factors include excessive weight, family history of facet joint difficulty, or traumatic injury.

Patients who suffer from lumbar facet syndrome typically report experiencing pain within the lower back region. Further, they may describe that their pain radiates from the lower back to the hip and buttock region. Should the facet joint within the cervical area be affected, the pain can manifest itself within the upper back, neck, shoulders, or even within the head.

Generally, pain associated with facet syndrome is described as a dull, achy pain that is exacerbated by physical activity. Over time, as the condition persists, pain episodes may last for longer periods of time. Other symptoms that may accompany the pain include:

  • Pain that radiates from the lower back to the thighs, pelvic areas, or buttocks
  • Pain that radiates from the neck to the shoulders, arms, or head
  • Pain that peaks in the morning or evening
  • Pain that is aggravated during weather changes
  • Worsening pain during walking, standing, and sitting for long periods of time
  • Abnormal curvature of the spine
  • Arm or leg weakness
  • Numbness
  • Sluggish reflexes

Individuals with facet syndrome generally suffer from other comorbid conditions. The conditions may include herniated disc disease, osteoarthritis, degenerative disc disease, or spinal stenosis.

Spinal Osteoarthritis

Typically affecting the lower back, spinal osteoarthritis is caused by the breakdown of the cartilage found within the facet joint. This cartilage acts as a buffer between the bones of the spine and is comprised of a smooth and elastic tissue. Without this protective cartilage, the vertebrae of the spine would be at risk for constant damage or irritation owing to everyday activities.

Indeed, the precise cause of spinal osteoarthritis is generally unknown. Nonetheless, there are several known factors that likely contribute to the development of spinal osteoarthritis, including genetics, age, weight, gender, and comorbid medical conditions. Those who are known to be most at risk for the condition are individuals in their mid-30s who have a history of being highly involved in athletics or who have a history of work requiring repetitively moving heavy objects.

Most patients with spinal osteoarthritis describe pain in the lower back and neck that is quite severe. Over time, as the cartilage continues to age and degenerate, the patient’s pain is likely to increase. This condition is likely to be accompanied by limited back mobility and flexibility. Patients with spinal osteoarthritis are also at risk for developing painful bone spurs. More specifically, as the protective cartilage degenerates, the bones of the facet joint are at risk for rubbing together leading to bone spurs. Bone spurs are particularly painful as they compress and pinch the nerves of the spine.

Patients suffering from spinal osteoarthritis may benefit from a number of specific stretching exercises targeted at increasing flexibility and mobility of the back. Further, patients may be encouraged to regularly practice abdominal stretches to increase the strength of the abdomen. This, in turn, provides the spine with increased support and is believed to decrease symptoms of pain and discomfort associated with spinal osteoarthritis. Moreover, facet joint injections and medial branch blocks have received support as being beneficial to treating the pain associated with this condition.

Degenerative Disc Disease

Another condition associated with significant back and neck pain is degenerative disc disease. Along with typical aging, the intervertebral discs of the spine can become worn down and deteriorate over time. These discs can be found in between the vertebrae of the spine. Their primary function is to protect the bones of the spine from damage during normal day-to-day activities. Thus, this daily wear and tear damages the disc, causing it to bulge beyond the space between vertebrae. The bulging disc then places pressure on nearby spinal nerves, which can lead to irritation of the nerve, inflammation, and ultimately pain.

Typically, patients with degenerative disc disease report pain that may begin in the back and radiate outward to the buttocks and legs. While the area near the bulged disc is typically the initial location of pain, the discomfort is likely to spread to all areas of the spine over time. Most commonly related to sciatica, or pain experienced in the leg, are damaged discs in the lumbar area. Damage to the intervertebral discs in this area can also lead to sensations of numbness, tingling, and pain in the lower extremities. In contrast, damaged intervertebral discs in the cervical region can lead to these same symptoms in the upper extremities. Physicians typically refer to the pain associated with damaged intervertebral discs as discogenic pain. Other significant complications can also occur with a damaged intervertebral disc. For instance, the intervertebral disc can tear, develop fissures, and even burst.

Diagnosis of degenerative disc disease involves a detailed evaluation of the patient’s course of symptoms, medical history, and a physical examination. Physical examination for degenerative disc disease typically necessitates for range of motion and rigidity of the spine and neck. Further, the physician will assess for any signs of weakness, tenderness, or pain. The use of other forms of evaluation may be required, such X-rays and MRI, in order to determine the degree of deterioration of the individual’s intervertebral discs.

There are a number of potential treatments for patients struggling with chronic pain associated with degenerative disc disease. Patients are typically encouraged to attempt more conservative treatments, such as over-the-counter medications or rest. Occasionally, physicians may recommend physical therapy or other specific exercise routines. For patients experiencing pain that has not responded to these interventions, it may be necessary for these patients to begin a short-term pain management plan that includes the use of narcotic medications. Other options, including epidural steroid injections, may be recommended.

Herniated Disc

Typically occurring when a portion or all of an intervertebral disc ruptures, herniated disc disease is associated with severe pain, lower extremity numbness, or overall general weakness. These symptoms likely occur due to the compression placed on the spinal cord and other spinal nerves as the result of the bulging intervertebral disc. These symptoms generally are reported within the lower back, but may also radiate to the hips, buttocks, or legs. Further, the symptoms of a herniated disc may not emerge immediately. Indeed, many patients report that their symptoms occurred gradually and were exacerbated by sitting or standing for long periods of time.

As with the other conditions, a full initial assessment is required for the diagnosis of a herniated disc. Physicians assessing for this condition will pay particular attention to any reported numbness, weakness, or lack of strength or dampened reflexes, as well as assess posture. An individual’s muscles and nerves can be assessed for health using an electromyography test. Further, the size and location of the herniated disc can be determined using a myelogram. MRIs and CT scans may be necessary to assist the physician with proper diagnosis.

Similar to other pain conditions, herniated disc pain may be treated in a number of ways. Initial treatment recommendations may require rest and physical therapy. Patients may also wish to take over-the-counter pain medications to ease their discomfort. Typically, patients with a herniated disc will need to make significant lifestyle changes, such as regular stretching and limiting heavy lifting or other strenuous exercises. For refractory pain, patients may be candidates for epidural steroid injections or other nerve blocks.

Spinal Stenosis

By the age of 50, it has been estimated that nearly 95% of adults will experience degenerative changes within the spine, known as spinal stenosis. Typically, the emergence of difficulty with regard to pain and discomfort associated with this condition tends to occur among individuals over 60 years of age. During aging, the bones in the spine, known as vertebrae, can harden and become overgrown. As this occurs, the spinal canal, which protects the spinal nerves, narrows. This narrowing of the spinal canal places pressure on the spinal cord and other spinal nerves. This pressure can irritate the nerves, which can lead to sensations of pain, numbness, or weakness.

Degeneration can also involve the intervertebral discs, which contain protective synovial fluid. This process involves a gradual loss of the protective synovial fluid that also leads to a narrowing of the spinal canal. The decrease in synovial fluid generally occurs naturally with aging. Once the spinal canal narrows, there is some risk for the development of arthritis. In fact, arthritis is one of the most common causes of spinal stenosis.

Diagnosis of spinal stenosis can be done through a number of methods. The physician generally will rely upon the patient’s account of recent activity and description of symptoms. Further, the physician is also likely to take into account the patient’s medical history. Physicians will generally inquire about any previous injuries to the spine and other general health problems. This will help ensure that the physician arrives at the most accurate diagnosis. Along with an oral history, physicians will generally also conduct a physical examination. This exam typically includes an assessment of the individual’s degree of muscle strength, mobility, and flexibility. Other tests can be conducted in order to aid in the physician’s diagnosis, including X-rays, MRIs, and CAT scans. These procedures utilize both three-dimensional and two-dimensional imagery, along with cross-sectional images, to diagnose the underlying cause of spinal stenosis. Physicians can also inject a dye, illuminating any abnormalities within the spinal canal in a procedure known as a myelogram.

Spinal stenosis can be treated in a number of ways and many of them do not involve the use of surgery. For instance, many individuals will experience relief from the pain and discomfort associated with spinal stenosis through the use of non-steroid anti-inflammatory drugs (NSAIDs) or other over-the-counter pain relieving medications. Physical therapy may also be recommended, which involves a series of prescribed exercises to improve strength and flexibility of the abdomen and muscles of the back. Other alternative therapies are also available, including acupuncture and other chiropractic techniques that have shown promise in treating spinal stenosis pain. Should a patient’s symptoms of pain and discomfort be unresponsive to these non-surgical techniques, surgery to relieve pressure on the spinal cord may be the only option.

Recent Research On Facet Joint Injections And Medial Branch Blocks

Extant literature has provided support for the use of facet joint injections and medial branch blocks in the treatment of back and neck pain. Further, it has also been suggested that these treatments can help prevent a patient from requiring surgery to relieve the pain and discomfort owing to a medical condition. One benefit of these treatments is that they can be used in combination with other conservative therapeutic techniques, such as physical therapy or over-the-counter medication. This may help reduce the recovery time for patients to return to their previously held levels of functioning and enjoy an improved quality of life.

Previous literature on the use of lumbar medial branch blocks for the management of facet joint pain has supported the efficacy of this intervention. Indeed, previous studies have suggested that the combination of corticosteroids and local anesthetics account for the overall effectiveness of these procedures. Interestingly, there are a number of controlled trials whose results have provided some support for the role of facet joint injections and medial branch blocks in the diagnosis of facet joint conditions. At this time, best practice guidelines support using these techniques in conjunction with imaging studies in order to most accurately diagnosis the individual’s condition.

A recently conducted study involving patients with low back pain revealed that facet joint injections were successful in relieving the pain of 74% of the population. Moreover, a two-year follow-up of patients that had received diagnostic lumbar medial branch blocks revealed that this technique was successful in diagnosing 93% of the population of individuals selected to be in the study. Indeed, following a one-year observational period, nearly 90% of these individuals continued to benefit from the therapy targeted at the facet joint. Other studies have also corroborated these findings. Facet joint injections and medial branch blocks are regarded as particularly ideal given that they have a very low incidence of side effects. Moreover, the effects of these interventions can be experienced almost immediately.

Research to date has suggested that patients undergoing these interventions are expected to achieve a 50% improvement in lost function. Further, the American Society of Regional Anesthesia and Pain Medicine (ASRAPM) recently published an article on data examining clinical outcomes of patients diagnosed with facet syndrome by way of cervical medial branch blocks. Results from this study indicated that nearly 94% cases of facet syndrome were positively identified. Taken together, these findings provide ample support for the effectiveness of facet joint injections and medial branch blocks in the diagnosis and treatment of facet pain.

Conclusion

Both facet joint injections and medial branch blocks have received support for managing chronic pain within the neck and back. In particular, these techniques are recommended for pain that originated within the facet joints of the vertebrae of the upper and lower back, as well as the neck. These procedures involve injecting a solution of anesthetic and corticosteroids into the joint, which reduces inflammation and pain in the surrounding area. Previous work has supported the use of these procedures in aiding diagnosis of pain conditions. Both facet joint injections and medial branch blocks provide patients with significant reductions in pain and can help the patient regain their ability to carry out necessary daily functions. These interventions are regarded as safe and effective treatment options and are believed to play a significant role in preventing premature or unnecessary invasive back surgery.

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