Dr. Nick Scott performs Epidural Steroid Injection. Watch this video and watch Epidural Steroid Injection performed live.
Pain Doctor Nick Scott Performs Epidural Steroid Injection.
Healthcare research estimates that 90% or more of all adults will experience at least one bout of pain that has an effect on their ability to function or perception of life quality. The Centers for Disease Control (CDC) has released papers that confirm the profound potential effects on motion, functional status, and occupational status of chronic back pain in particular. It follows that chronic pain in general may result in negative economic consequences.
Estimates indicate that consistent back pain is associated with up to 100 billion U.S. dollars’ worth of lost earnings per year. This may be primarily made up of absences from work and occupational disability. This type of pain may also be related to the increased uptake of healthcare resources and impaired productivity at work. This has led to an increased demand for new developments and research in the treatment of chronic back pain. There have been considerable advances in pain treatments over the last few decades, in terms of clinical trial data and novel applications that have successfully completed development and made it to the post-marketing stage. Many of these are now recognized as conventional therapies in the field of chronic pain management.
An example of the above is epidural steroid injections. This is a technique associated with robust and effective treatment of chronic pain that is most likely to originate in the general region of the spine. Many U.S. spinal pain associations and societies recognize this treatment option as a valid component of pain management. Types of pain to which epidural steroid injections may be applied include chronic pain perceived as emanating from the back or neck, and pain that starts in the back or neck and then radiates through an extremity (i.e. radiculopathy). These bodies also support the role of epidural steroid injections in the improvement of disability and debility resulting from these types of chronic pain.
This technique has demonstrated the ability to decrease or even reverse persistent pain in many cases. Some patients may experience either of these effects after only one injection. However, others may require repeat injections over a period of time for the same result. Epidural steroid injections may result in some adverse effects. These are mainly produced by the steroids incorporated in their formulations. Common side effects of steroids may include abnormal increases in emotional irritation, bodyweight fluctuations, immune system depression, and increased risks of gastric ulcers.
Epidural injections were first documented in 1885 by James Leonard Corning, a neurologist. However, these injections delivered cocaine, not steroids. In 1901, this technique was specifically demonstrated as a treatment for pain. By then, other physicians had adopted this treatment, using an approach similar to some in use today. Their patients were recorded as having conditions known then as sciatica, but might be categorized today as a form of radiculopathy. About 30 years later, caudal epidural injections were described in many papers as an increasingly-established method to treat pain. These injections were completed using drugs other than steroids, however. Steroids were first injected into the epidural space in the 1950s. Since then, the evidence of their efficacy has grown in strength and quality. The procedure has been applied to many other disorders, although some researchers believe they are most effective in cases of radiculopathy.
Epidural steroid injections are administrations of pain-relieving drugs directly into the spine. However, they are performed in a way that promotes safety while effectively distributing steroids. The needle passes between the bones (or vertebrae) of the spine.
The Anatomy Of The Spine
The spinal column includes a number of bones that are shaped so as to allow the spinal cord to pass through them when they are in alignment. This is also known as the vertebral column, or what is commonly referred to as a backbone. The column runs from the base of the skull to the top of the pelvis. The vertebral column functions to give structure to the body in this region, and to protect the spinal cord.
The vertebral column is divided into a number of regions. The cervical region is made up of the first seven vertebrae and forms the neck. The thoracic region consists of the next 12 spinal bones. This is the upper to middle back region. The lumbar region comprises the lower back, and is made up of five vertebrae. The next region down is the sacral region, then the coccygeal region, which consist of four fused vertebrae, also known as the tailbone. These regions are defined by differences in the structure and properties of their respective vertebrae. When combined, this results in the normal curve and shape of the spine. Vertebrae also possess long, thin processes to connect to muscles and other bones, which may vary depending on region.
The spinal cord is a large tube containing nerves and other tissues that is located inside the vertebral column. It is responsible for the transmission of pain, sensation, and motor impulses to and from the brain. The spinal cord progresses downward from the brain and through the spinal column. It is associated with important roles in the ability to move, perceive the environment, and react to external stimuli. Spinal cord injury or disease may lead to long-term disability or loss of sensation. This is protected against by the spinal column, and by layers of tissue, known as the meninges, located around the cord.
The meninges are membranes that surround the spinal cord. They are also present in the brain. The function of the meninges is to separate the spinal cord and brain from bones, and to protect the cord. The meninges are the pia mater, the arachnoid, and the dura mater. The dura mater was named for its toughness (dura is Latin for tough). This membrane is strong and resilient. Cerebrospinal fluid is contained within this membrane. This liquid supplies some nutrients to the tissues of the brain and spinal cord, and also serves for supplementary shock absorption.
The epidural space is the area around or outside the dura mater. It is found close to the vertebrae. It also contains tissues such as lymph and small blood vessels (for nutrients and drainage), spinal nerve roots, and some fat. There is no epidural space in the brain, but it is present in all regions of the spine.
Spinal nerve roots are junctures at which spinal nerves split off from the spinal cord to branch out into the body. These run through and around vertebrae (and through the epidural space) to form the basis of the peripheral nervous system. Chronic pain may arise from mechanical or chemical damage to spinal nerve roots. These injuries may also be associated with increased muscle weakness (or paresis). In severe cases, this may extend to complete paralysis.
How Are Epidural Steroid Injections Performed?
The epidural space is a safe and appropriate injection target as it offers convenient access to spinal nerve roots without invasion of the areas around the central cord (e.g. near the arachnoid membrane), which has resulted in severe adverse events in earlier pain research. The epidural space is accessible to any approach in any spinal region. It is generally regarded as a reproducible and robust method of delivering pain-relieving medications in cases of chronic or intense pain.
Epidural steroid injections may be completed in a clinic, and doctors typically needs no more than 15 minutes per procedure. Intravenous sedation, in conjunction with equipment to monitor vital signs, may be used if required, but this is usually not necessary. The procedure may start with the disinfection of the skin through which the pain specialist plans to insert a needle. The patient lies face downward on a table or bed, which is the best position for all approaches and targets. The specialist will administer a local anesthetic to the disinfected skin to avoid any discomfort while the injection takes place. The procedure is usually accompanied by non-invasive imaging such as computed tomography. This gives a real-time picture of the epidural space and the position of the needle relative to the nerve root in question. Imaging may be further enhanced with contrast material, which may be injected with or before the steroids.
Next, the specialist delivers the formulation. This is only done when accurate, safe, and optimal needle placement is achieved. The specialist ensures that just enough of the drugs are injected to give an appreciable response and to cover enough of the area around a nerve root. Too much fluid introduced into the epidural space may increase the risk of complications.
There are three main forms of epidural steroid injection:
- Caudal—This approach involves the placement of a needle into the epidural space of the sacral region. It has been adapted from the classic techniques used in the development of the epidural injection as a pain treatment. This approach is associated with the possibility of using larger volumes of medication than the other techniques below. This is one of the main advantages of the caudal approach. It is also associated with reduced risks of inadvertent dural membrane damage. Several studies support the positive effects of the caudal approach in pain caused by many disorders. These include radiculopathy. The outcomes of caudal injections in other conditions are slightly lacking in the literature, but the existing data indicates some benefits in these cases. The caudal approach may be less specific in target than other techniques, however.
- Transforaminal—This approach brings the needle into the epidural space at the side of a spinal bone. This results in a unilateral injection, as opposed to the interlaminar approach, which is bilateral. This is useful for cases in which the patient has surgical hardware such as screws or rods that must be avoided or injected around. Transforaminal injections may be associated with a greater need for imaging technology, as the specialist has less points of reference when inserting a needle. Nevertheless, this approach is regarded as being comparable to the interlaminar approach in terms of accuracy. Transforaminal injections may also be associated with lower incidences of dural puncture. Some studies conclude that the transforaminal approach may be associated with increased pain relief in patients with nerve damage when compared to similar cases treated with the interlaminar or caudal approach.
- Interlaminar—This may be the most popular approach used to complete injections. In these cases, the needle is inserted in the epidural space between a pair of vertebrae. This allows the formulation to spread to nerve roots on both sides of the midline of the spinal column. Interlaminar injection is associated with pain relief in cases of patients with radiating pain resulting from damage to the cartilage found in the spinal column. The interlaminar approach is also associated with efficacy in many other forms of back pain. This technique is associated with increased specificity compared to some others. Research has shown that drugs delivered with the interlaminar approach may have a better chance of covering damaged nerve roots on the left and right of the spinal cord. The interlaminar approach may require less fluid to be injected in comparison to caudal procedures. However, it is also associated with great risk of dural puncture (i.e. damage to the dural membrane) in the course of a procedure.
These different techniques for epidural steroid injection administration are commonly used in medical practice and clinical studies. All three are associated with the rapid reduction of pain in many cases. The duration of pain relief following an injection procedure may range from a number of weeks to a number of months. The magnitude of this response is associated with many variables or factors, some of which are being studied in ongoing research. The number and frequency of injections that result in pain relief for the individual patient may also depend on many factors. In some cases, a single injection may not result in the expected treatment effect. These patients may require several repeat injections scheduled over a period of time. Some researchers have concluded that repeat injections may not yield pain relief. However, if one epidural steroid injection results in some relief, your pain specialist may recommend you arrange another shortly afterward to assess the possibility of any increase in this benefit.
Alternatives to epidural steroid injections include physical therapy and conventional oral medication. Some studies indicate that up to 90% of all patients with back or neck pain may not require interventional procedures following conservative first-line treatments. If these fail though, and the pain becomes or remains chronic and severe, further consultation with your pain specialist may result in an agreement to try epidural steroid injections.
Reductions in pain following an epidural steroid injection may be different for each patient, as outlined above. The factors that may modify a response to treatment can also be relevant to other procedures. These variables include:
- The training, experience, and skill of the pain specialist or physician carrying out the injection
- The duration of symptoms before diagnosis and treatment
- The underlying cause of the pain
These may affect the magnitude of the individual response and the prognosis of the patient. Research suggests that pain relief following an epidural steroid injection is inversely proportional to the latency to accurate diagnosis and treatment. In other words, the longer a patient goes untreated, the less likely a treatment such as epidural steroid injection will have the desired effect.
Risks And Benefits Of Epidural Steroid Injections
The functions of epidural steroid injections are to effectively reduce pain and treat impairments in movement or function that are often related to pain. It may appeal to patients who would prefer a relatively convenient procedure without undue comfort. Epidural steroid injections are often an alternative to or contingency against more extensive procedures.
Epidural steroid injections may improve the functional status of some patients. For example, patients who have needed to take a leave of absence from, or even have lost, their employment may be able to return after a successful course of epidural steroid injection.
Many researchers and physicians regard epidural steroid injections as a safe and robust procedure. However, others believe they are associated with serious risks. Side effects of steroid injections may include transient headache, pain, increased anxiety, sleep disturbances, and impairments in sleep quality. Perceived increases in temperature, known as steroid flushes or hot flashes, may persist for a few days after a procedure. Bloating and nausea may also occur as a result of epidural steroid injections. Diabetic patients should be aware that these procedures may result in a temporary increase in blood sugar levels.
An epidural steroid injection may result in increased numbness of the arm or leg in which pain is normally experienced. However, this effect typically abates in about eight hours. The FDA has recently mandated further serious adverse event warnings for steroids, although the incidence of these is rare. These include an increased risk of stroke, loss of motor control, and death. These may also include immune system abnormalities, the risk of heavy bleeding, and other neurological abnormalities. Some reports claim that epidural steroid injections resulted in the infection of the epidural space or the meninges. This may result in conditions such as epidural abscess and bacterial meningitis. These infections have also been linked to subarachnoid injections, which is part of the reason these are no longer recommended.
Another risk of epidural steroid injection concerns needle placement and the inadvertent or inappropriate injection of the wrong area or structure. For example, a needle may invade the subarachnoid space instead of the epidural space, as above. This may result in infective disorders, and also in chronic pain, discomfort, or sensory deficits. Another possibility is the injection into, or too near to, a blood vessel in the epidural space. This may result in disproportionately large responses to steroids (including possible toxicity) and discomfort. Dural puncture may also result in persistent pain and discomfort, and the escape of cerebrospinal fluid into the epidural space, which can result in acute severe headache.
Some patients are at a higher risk of developing complications following epidural steroid injections. In these cases, a pain specialist may recommend an alternative treatment. Some characteristics and conditions that influence these risks include cardiovascular conditions such as increased blood pressure and coronary artery disease. Those who regularly take blood-thinning drugs may be at an increased risk of blood loss after epidural steroid injection. Those who are immunocompromised or suffer from infective conditions may not be suitable for this procedure. Patients with diabetes may be advised against undergoing steroid injection, depending on their current glycemic status. Those who have found they are particularly sensitive to the effects of steroids in the past may benefit from avoiding epidural injections.
Epidural steroid injections are typically associated with a period of effect lasting approximately six weeks. Their effects and risks of complications after time and regular injection schedules are not as well documented. Some patients appear to tolerate steroids well after repeated injections. However, others may be more susceptible to adverse effects, which are associated with the regular administration of these drugs.
Treatment Success After Injection
The success of this treatment, or a response approaching or exceeding the reduction in pain expected, can be influenced by many factors. Factors in treatment outcome may include the individual patient’s response and reactions to pain. This is known as pain sensitivity. Reactions to pain may also include psychological components. Pain catastrophization is a psychological term for disproportionately negative subjective responses to pain. This may also include the harboring of beliefs that convince the patient that he or she has a reduced chance of regaining normal function and a life free of pain. An impaired ability to cope with pain may influence both catastrophization and response to treatment.
Other factors that may affect treatment response include a history of depressive or anxiety disorders. Smoking, prior treatment with opioids, and whether or not the patient has had back surgery may also influence the outcomes of treatment with epidural steroid injection. Increased age may also increase the risk of treatment failure. As mentioned above, the failure to seek diagnosis or treatment early on in the development of the painful condition may also increase the risk of epidural steroid injection failure.
Researchers conclude that epidural steroid injections may take effect through a number of different mechanisms. Prominent among these is the main pharmacological property of steroid drugs, which is to reduce inflammation, that is associated with pain through the effects of inflammatory molecules on nerves. Inflammation is associated with many disorders, including neuropathy and many forms of arthritis. Steroids inhibit the formation of these molecules, and thus may significantly affect the sensation of further pain. These drugs also have positive effects on the membranes around nerve fibers and regulate nerve-cell signaling. This may also have a positive impact on the perception of pain following injection.
Some research suggests that the process of epidural steroid injection can have other effects on pain. The injection of material into the epidural space may also reduce pain by stimulating blood flow in the vessels mentioned above. This may also reduce pain signaling to some extent. The flow of liquid into the space may also clear away the existing inflammatory molecules around nervous tissue.
Conditions Related To Epidural Steroid Injections
Many people find that they will develop some form of back or neck pain, acute or chronic, temporary or long-term, at some point. This probability is influenced by many factors, including conditions that affect the many tissues (e.g. bone or muscle) connected to the spine. These include bone and nervous tissue, as well as the cartilage, muscles, tendons, and ligaments that surround and stabilize the whole structure. On the other hand, some cases of pain are idiopathic, or have an onset independent of any discernible factors or conditions.
In many cases, damage to or disorders of spinal nervous tissue is associated with centralized neck or back pain, and also radiating pain in the extremities. This pain may be described as many types, or forms, of pain. These include:
- Dull or throbbing pains
- Sharp or stabbing sensations
- Spreading (or radiating) pain
These pain types may change from one form to another over time, although the underlying condition remains the same. The pain may also change in duration and frequency as the condition progresses. Some forms of pain, or other symptoms that accompany pain, are characteristics of certain disorders.
Others may be diagnostic criteria of more than one disorder. These include:
- Stiffness, tightness, or cramping felt in back muscles
- Radiating pain
- Sensory deficits, increased weakness, or tingling in a leg or arm
- Pain or increased reactions to palpitation or pressure
Chronic pain and many of its related conditions may not be adequately addressed with first-line treatments such as physical therapy. In these cases, a specialist may recommend epidural steroid injections.
Specific disorders often treated with epidural steroid injections include:
- Cervical radiculopathy: Cervical radiculopathy is a condition associated with nerve damage in the cervical region. This causes pain in the neck, which also radiates through the arm.
- Degenerative disc disease: Intervertebral discs are round structures of cartilage located between each pair of vertebrae. These exist to offer shock absorption, support, and protection to these bones. Degenerative disc disease is a condition in which a section of a disc splits into two, or nearly into two. Degenerative disc disease may occur in all regions of the spine. It can require surgery in some cases, but if not, the pain may be managed with epidural steroid injection.
- Failed back surgery syndrome: Spinal surgeries are often carried out to correct a painful condition affecting the back (most often the lower back). However, this can result in accidental nerve damage. This may be associated with a resurgence of existing pain or the onset of a new type. Surgery may also be associated with the formation of scar tissue close to a spinal nerve root. This may also result in chronic pain.
- Intervertebral disc herniation(s): These are structural weaknesses in intervertebral disc material that result in mechanical damage to spinal nervous tissue. Mild forms of this condition that do not pose a serious threat to the spinal cord may be managed with epidural steroid injections.
- Lumbar radiculopathy: Lumbar radiculopathy is similar to cervical radiculopathy, in that it affects a spinal nerve that may serve a leg.
- Osteoarthritis: This is a degeneration of cartilage, to the point where bones may no longer be protected by this material. Osteoarthritis is associated with chronic pain and inflammation.
- Spinal deformities: These are conditions that often cause abnormally pronounced curves or other structural disorders in the spine. These deformities result from genetic mutations or other disease. Spinal deformity can be observed in any spinal region and may be associated with lifelong pain.
- Spinal infections: Some cases of spinal pain may be diagnosed as microbiological infections of the spine. Patients who complain of back pain who have concurrent fever should be assessed for spinal infections. Factors that affect the probability of infection include recent back surgery, immune deficiencies, prolonged drug use, and drug addiction.
- Spinal stenosis: This is the accumulation of material such as scar tissue within the vertebral column, which impinges on the spinal cord or on nerve roots. Spinal stenosis may result in chronic pain.
- Spondylolisthesis: This is a deformation of the spine over time. It is associated with wear and tear on the interfaces between spinal bones over time. This condition may be associated with pain if the nervous tissue is impinged by the new locations of vertebrae. Some research suggests that the prevalence of spondylolisthesis is approximately 5%.
- Vertebral fractures: These may result from the erosion of bone from vertebrae. This may be caused by blunt-force trauma, reductions in bone density, or increasing age.
- Whiplash: This is chronic neck pain caused by high-velocity impact to tissues such as ligaments, bones, and muscles in the region. Whiplash is associated with events such as motor traffic collisions, skiing accidents, and rollercoaster rides.
Epidural steroid injections have been shown to be effective in the conditions listed above. This has resulted in their endorsement by the American Society of Interventional Pain Physicians as a valid and evidence-based treatment. Many reviewers and analysts conclude that this treatment is safe and effective in many cases. Epidural steroid injection is also used in the diagnosis of neck or back pain. This may help a pain specialist detect the presence of a particular condition, and to design treatment based on diagnosis.
Diagnosis Of Related Conditions
Epidural steroid injections are indicated in cases of pain associated with a number of disorders and conditions. A pain specialist may recommend this treatment following a diagnosis of one of these. Diagnosis may include the request of a full medical history by the specialist.
This can include questions such as:
- What type of pain is experienced?
- How intense is the pain?
- How does pain affect other areas of life, such as normal daily activity?
- Which region(s) of the spine (or other areas) are affected by the pain?
- How long has this pain persisted?
This analysis may contribute to a better diagnosis, and an idea of possible targets and approaches for an epidural injection. However, many cases do not have enough distinctive hallmarks to be defined as being associated with one condition or another based on medical history alone. In these cases, the specialist may proceed to other techniques, such as imaging or experimental procedures. The specialist may begin treatment by recommending conventional first-line options to see if these adequately treat the condition. If this is not successful, it may indicate that the patient should attempt an epidural steroid injection instead.
The specialist may also assess for the presence of factors that increase the risk of treatment failure and symptom resumption after treatment. These are often known as yellow flags that can influence the treatment goals and expectations of the patient and physician. These may be included on some patient assessment tools available to specialists.
Other Applications Of Epidural Steroid Injections
Some research concludes that epidural steroid injection may contribute to avoiding potentially unnecessary invasive procedures. One study compared the responses of patients with disc herniations who had received epidural steroid injections to those of patients with this condition without a history of these treatments. The results showed that 19% of the patients not receiving epidural injection did not wish to proceed with corrective surgery, compared to 56% of the patients who did receive injections.
Chronic pain is an ever-increasing economic and healthcare concern. Some reports suggest that 90% or more of the total population will be subject to pain capable of affecting normal activity and function at one point or other in their lifetimes. A pain specialist may initially prescribe conventional first-line therapy to assess the severity of a condition. Patients who find these treatments ineffective may then opt for an epidural steroid injection. Epidural steroid injections may address conditions associated with damage of the spinal cord or of spinal nerves that split off from the cord and extend into the rest of the body.
Epidural steroid injections are procedures associated with reduced invasion and safety, and may delay or prevent the need for more intensive surgery. Patients receiving this treatment may find that their pain is effectively reduced or even gone following the procedure. Epidural injections do not require long recovery times, and can be a part of a normal day’s schedule. These procedures are extensively documented and supported in scientific literature.
Many patients may experience effective pain relief after their first injection. In other cases, repeated injections in quick succession may be necessary. The specialist treating these patients can design a long-term plan based on this. The success of this treatment likely will be affected by many factors, including psychosocial and psychiatric factors. A specialist will be happy to assess your suitability for epidural steroid injections.
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