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Spinal injections
The Spine Journal 1 (2001) 387–389
Spinal injections: past, present and future Jeffrey A. Saal, MD* Over the past 20 years, I have participated in and witnessed significant changes in the spine care field. In my opinion, some of these changes have been good, whereas others have been deleterious. A discussion of spinal injections can serve as a window to view this evolutionary process. Spinal injections have become mainstream and commonplace over the past 10 years. The events and developments, which helped create this phenomenon, are worthy of analysis. To understand where we are going, we must evaluate where we started. Early on, spine care was solely dictated by the concrete-structural/psyche paradigm. This has been replaced by a paradigm shift that emphasized functional optimization over structural alteration. This approach incorporated mediation of inflammation and neuromodulation as pathways to achieve pain control in order to pave the way for functional restoration. This new paradigm did not de facto require the surgical alteration of spinal structures.
The past Before the early 1980s, spine care was dominated by the myelogram. The premise was very simple. If someone had pain and a “defect” was noted on the myelogram, a surgery was immediately warranted. The idea of nonoperative care was thought to be frivolous bordering on quackery. When one looks at the nonoperative options available to patients at that time, the prevailing thoughts were probably correct. The most frequently employed nonoperative option was to confine the patient to strict bed rest while attached to traction. Mobilizing a patient was thought to be deleterious and physical rehabilitation downright harmful. As a consequence of this philosophy, when I first began in practice the chairman of a local university neurosurgical department brought me up on charges in front of the Medical Board of Quality Assurance for treating patients with active care and recommending against surgery. Over time, it became obvious that many patients did not improve after surgical intervention. The explanation frequently espoused was the patient’s psychological imbalance. The surgery was declared a FDA device/drug status: Not applicable. Nothing of value received from a commercial entity related to this research. * Corresponding author. 2884 Sand Hill Road, Suite 110, Menlo Park, CA 94025, USA. Tel.: (650) 926-1259; (650) 854-7398.
success, but the blame for the lack of improvement was placed squarely on the patient’s shoulders. Later, in an effort to improve outcomes and improve the selection criteria for surgery, “conservative” care was offered to more patients. In a limited fashion epidural corticosteroid injections to reduce pain were introduced. During this era, neural compression was considered to be the sole reason for all spinal pain. The compression could be the result of disc “prolapse” or hypertrophic changes. The evaluation of compression was considered to be very straightforward; it was either present on the myelogram or it was not. Axial pain was another matter. It was thought to be a result of segmental instability. Defining instability was akin to holding smoke in your hand. The surgical community firmly believed in its presence, and spinal arthrodesis was introduced into the surgical care of the spine. Radical discectomies and facetectomies performed to treat neural compression often led to true instability. Salvage fusions were developed to deal with this iatrogenic problem. Before the introduction of internal fixation hardware, fusion failure rates were quite high and multiple surgeries became commonplace. During this time, pain programs were introduced to deal with the chronic pain patients created by multiple failed surgeries. The pain clinics began using epidural injections performed without fluoroscopic localization. Some centers expanded their use of injections to preoperative patients. Interest in finding alternative diagnoses rather than relegating all spinal pain to the intervertebral disc created interest in the facet (zygapophyseal) joints and sacroiliac joint. Injection techniques were developed to evaluate and treat these proposed areas of pathology. A giant step in spine care was heralded by the introduction of advanced imaging techniques. For the first time, computed tomography allowed an accurate assessment of the lateral recess. This revealed that many surgical failures were probably secondary to a failure to recognize concomitant lateral canal stenosis. The computed tomographic scan also demonstrated the facet joints, facet joint cysts and many varied forms of disc pathology that were never adequately evaluated during the myelogram era. With the advent of magnetic resonance imaging, disc pathology could be more accurately classified and internal derangement of the disc could be demonstrated.
1529-9430/01/$ – see front matter © 2001 Elsevier Science Inc. All rights reserved. PII: S1529-9430(01)00 1 5 0 - 4
388
Editorial / The Spine Journal 1 (2001) 387–389
The improved imaging of spinal pathology led to the development of new approaches to diagnose and treat these conditions. Injection techniques became more precise. Epidural injections were delivered under fluoroscopic control. Transforaminal selective epidural injections were developed to deliver medications to the offending lateral recess and nerve root complex. Facet joint injections became more precise, and the anatomic work that defined the innervation of the facet joint led to the development of rhizolysis techniques. Neuroanatomic work opened the pathway to considering spinal pain along neurophysiologic lines, not just morphologic ones. The discovery of high levels of inflammatory enzymes in the disc, and the realization that a large percentage of patients with lumbar disc herniation could be treated nonoperatively, highlighted the biochemical aspects of pain generation and the capability of treating spinal pain without the necessity of altering spinal structure surgically. Additionally, the discovery of substance P in the disc and dorsal root ganglion led to a search for alternative ways to identify and treat spinal pain. On the basis of the imaging advances, the neuroanatomic findings, the chemical mediator discoveries and the reported nonoperative treatment successes, a new spine care paradigm began to evolve. The paradigm incorporated the focused use of corticosteroid injections and neuroablative procedures to facilitate the progression of functionally based rehabilitation programs. Additionally, injections were increasingly being used in an attempt to diagnose spinal pain generators more accurately. The focus shifted to one that promoted improved patient function as the pre-eminent outcome yardstick. Originally, there were very few spine specialists trained and experienced to perform spinal injections.
Jeffrey A. Saal, MD
As the popularity of injections grew, the need to train more physicians ensued. Anesthesia pain programs and physiatry training courses grew to meet this demand.
The present The treatment algorithm currently incorporates injection procedures to facilitate functional improvement. The concept is straightforward. If an inflammatory focus is present and can be incriminated as a dominant cause of the patient’s pain generation, then a precisely injected corticosteroid can be used to reduce the inflammation and permit progression of a physical rehabilitation program to enhance functional improvement and recovery. Simultaneously, surgeons are asking for more precise information regarding pain generation to plan operative interventions. Lumbar selective nerve injections, facet injections, medial branch dorsal ramus injections and diagnostic disc injections are used in many centers to sort out complex spinal pain patients. The growing demand for therapeutic and diagnostic injections has given birth to the injectionist (ie, the interventionist). This evolutionary phenomenon has led to a spread from the original core “values.” The interventionists have begun to use their procedures outside of the established algorithm. Multiple corticosteroid injections are being used in place of physical rehabilitation. Many patients are being treated with procedures and medications and are never exposed to rehabilitation efforts to improve function. Likewise, patients with “simple” back pain are undergoing facet rhizolysis procedures and discography at the top of the algorithm rather than at the originally intended later stages. “Shoot first, ask questions later” appears to be the prevailing motto. The number of injections performed on any individual patient was increased. One begins to see patients who have undergone 20 to 50 epidural injections. The cost of injection-based workups before surgery has increased to as high as $8,000 to 10,000, and it is not entirely clear that this has led to improved outcome. The proliferation of spine fusion to treat axial low back pain has led to the increased use of discography. However, as surgical failures are seen, discography has often been blamed as the culprit. It has been said that discography cannot predict the success of fusion surgery. Therefore, discography lacked specificity, and its benefits are questionable. This has raised further questions regarding the existence of symptomatic discogenic pain. The flaw in this reasoning is using a therapeutic intervention (especially one with mixed results) as the yardstick to measure the precision of a test finding or the presence of a diagnostic entity. Pain programs proliferated even further in an effort to absorb the chronic pain patients created by the spine care system. These developments have led to an increase in the use of injection procedures. Remarkably, this has all occurred during a time when there are no single randomized clinical trials validating the use of injection procedures or fusion surgery.
Editorial / The Spine Journal 1 (2001) 387–389
Inevitably, with procedure proliferation comes backlash. The lack of randomized trials to support injection therapy or injection pain localization has repeatedly been pointed out. Payers question the need for fluoroscopic localization and whether injections can affect the eventual outcome of the patient. Quality of life as it relates to pain relief and functional improvement are often ignored. Studies that evaluate injections as stand alone therapy often lead to questioning the effect of epidural and facet injections. Unfortunately, these studies have evaluated injections out of context to their intended use, because the intention of injection therapy is an adjunctive therapy to promote function-based rehabilitation. Many publicized studies have failed to test this hypothesis; instead they have tended to analyze injection procedures as a stand alone, all or none therapeutic intervention. Nihilists often state that because no one really knows where pain is coming from, injections, interventional diagnostics and fusion surgery are all useless. This has given license to the payers to shift spine care to general medicine physicians and deny access to specialists. A recent randomized clinical trial reported that epidural injections might help a significant number of patients avoid lumbar surgery. Studies validating thera-peutic facet injections, however, remain lacking, and there are no data to firmly support the use of selective epidural injections versus standard lumbar epidural injections. The future As we attempt to move the field forward, let us take a moment to look at questions raised from clinical experience using spinal injection procedures. In selected cases of lumbar disc herniation and spinal stenosis, epidural corticosteroid injections when coupled with physical rehabilitation may help promote recovery without surgery. In selected cases of lumbar spinal stenosis, selective nerve root block may be able to identify the offending spinal nerve. In select cases, the Z-joint complex may be identified as a pain generator, and neuroablative procedures may reduce pain from this source for a period of time. Selected patients with sacroiliac pain may be diagnosed with localized injection. Selected patients after motor vehicle accidents with cervical posterior ligamentous complex and facet joint injuries may be amenable to neuroablative procedures targeted at the offending dorsal ramus branch. Selected patients with discogenic pain may be identified by diagnostic disc injection (ie, discography). There is no one imaging marker that accurately and reproducibly identifies a painful disc, facet joint or any other spinal structure.
389
Psychological factors modify pain perception and should alter the interpretation of pain provocation diagnostic procedures. Poorly performed injection technique may increase and prolong a patient’s pain response. In order to improve the quality of spine care and injection procedures, future endeavors should include the following key elements: A return to patient-centered care that promotes functional optimization through the least invasive and risky therapeutic intervention available to that particular patient at that point in time. This should take into consideration the diagnosis, the degree of impairment and the level of chronicity. An effort to improve the clinical abilities of interventionists. This should include physical examination skills, and the prescription and monitoring of the rehabilitation program. Alternatively, interventionists should work in conjunction with skilled clinicians to handle the care of the patient before and beyond the intervention. The future of injection therapy will be predicated upon ongoing research efforts, which should include: Research to investigate the ability of injection procedures to improve patient outcomes; Research to investigate the ability of injection procedures to precisely, reproducibly and accurately identify spinal pain generators; Research to evaluate the efficacy of varying doses of different preparations of corticosteroids; Research to evaluate the value of precise epidural localization of medication in the various categories and types of disc herniations and spinal stenosis; Research to evaluate the true incidence and natural history of painful internal disc derangement; Research to determine the combined impact of exercise and injection efforts on the treatment of the various categories of painful spinal disorders; The discovery of new agents to specifically block the chemical mediators of pain and inflammation; Discovery of specific imaging markers of pain. The bottom line should be very clear. Our role as spine care practitioners is to improve our patients’ health and well being. Sometimes this path has potholes and pitfalls. In the ideal world all of the medicine we practice will be evaluated by RCTs. However, in the present real world, physician judgment is still required. Judgment can be defined as the making of a decision based on facts that are not clearly in evidence. Therefore, we must sharpen our judgment and never lose sight of the target, our patient.
Spinal injections: past, present and future Jeffrey A. Saal, MD* Over the past 20 years, I have participated in and witnessed significant changes in the spine care field. In my opinion, some of these changes have been good, whereas others have been deleterious. A discussion of spinal injections can serve as a window to view this evolutionary process. Spinal injections have become mainstream and commonplace over the past 10 years. The events and developments, which helped create this phenomenon, are worthy of analysis. To understand where we are going, we must evaluate where we started. Early on, spine care was solely dictated by the concrete-structural/psyche paradigm. This has been replaced by a paradigm shift that emphasized functional optimization over structural alteration. This approach incorporated mediation of inflammation and neuromodulation as pathways to achieve pain control in order to pave the way for functional restoration. This new paradigm did not de facto require the surgical alteration of spinal structures.
The past Before the early 1980s, spine care was dominated by the myelogram. The premise was very simple. If someone had pain and a “defect” was noted on the myelogram, a surgery was immediately warranted. The idea of nonoperative care was thought to be frivolous bordering on quackery. When one looks at the nonoperative options available to patients at that time, the prevailing thoughts were probably correct. The most frequently employed nonoperative option was to confine the patient to strict bed rest while attached to traction. Mobilizing a patient was thought to be deleterious and physical rehabilitation downright harmful. As a consequence of this philosophy, when I first began in practice the chairman of a local university neurosurgical department brought me up on charges in front of the Medical Board of Quality Assurance for treating patients with active care and recommending against surgery. Over time, it became obvious that many patients did not improve after surgical intervention. The explanation frequently espoused was the patient’s psychological imbalance. The surgery was declared a FDA device/drug status: Not applicable. Nothing of value received from a commercial entity related to this research. * Corresponding author. 2884 Sand Hill Road, Suite 110, Menlo Park, CA 94025, USA. Tel.: (650) 926-1259; (650) 854-7398.
success, but the blame for the lack of improvement was placed squarely on the patient’s shoulders. Later, in an effort to improve outcomes and improve the selection criteria for surgery, “conservative” care was offered to more patients. In a limited fashion epidural corticosteroid injections to reduce pain were introduced. During this era, neural compression was considered to be the sole reason for all spinal pain. The compression could be the result of disc “prolapse” or hypertrophic changes. The evaluation of compression was considered to be very straightforward; it was either present on the myelogram or it was not. Axial pain was another matter. It was thought to be a result of segmental instability. Defining instability was akin to holding smoke in your hand. The surgical community firmly believed in its presence, and spinal arthrodesis was introduced into the surgical care of the spine. Radical discectomies and facetectomies performed to treat neural compression often led to true instability. Salvage fusions were developed to deal with this iatrogenic problem. Before the introduction of internal fixation hardware, fusion failure rates were quite high and multiple surgeries became commonplace. During this time, pain programs were introduced to deal with the chronic pain patients created by multiple failed surgeries. The pain clinics began using epidural injections performed without fluoroscopic localization. Some centers expanded their use of injections to preoperative patients. Interest in finding alternative diagnoses rather than relegating all spinal pain to the intervertebral disc created interest in the facet (zygapophyseal) joints and sacroiliac joint. Injection techniques were developed to evaluate and treat these proposed areas of pathology. A giant step in spine care was heralded by the introduction of advanced imaging techniques. For the first time, computed tomography allowed an accurate assessment of the lateral recess. This revealed that many surgical failures were probably secondary to a failure to recognize concomitant lateral canal stenosis. The computed tomographic scan also demonstrated the facet joints, facet joint cysts and many varied forms of disc pathology that were never adequately evaluated during the myelogram era. With the advent of magnetic resonance imaging, disc pathology could be more accurately classified and internal derangement of the disc could be demonstrated.
1529-9430/01/$ – see front matter © 2001 Elsevier Science Inc. All rights reserved. PII: S1529-9430(01)00 1 5 0 - 4
388
Editorial / The Spine Journal 1 (2001) 387–389
The improved imaging of spinal pathology led to the development of new approaches to diagnose and treat these conditions. Injection techniques became more precise. Epidural injections were delivered under fluoroscopic control. Transforaminal selective epidural injections were developed to deliver medications to the offending lateral recess and nerve root complex. Facet joint injections became more precise, and the anatomic work that defined the innervation of the facet joint led to the development of rhizolysis techniques. Neuroanatomic work opened the pathway to considering spinal pain along neurophysiologic lines, not just morphologic ones. The discovery of high levels of inflammatory enzymes in the disc, and the realization that a large percentage of patients with lumbar disc herniation could be treated nonoperatively, highlighted the biochemical aspects of pain generation and the capability of treating spinal pain without the necessity of altering spinal structure surgically. Additionally, the discovery of substance P in the disc and dorsal root ganglion led to a search for alternative ways to identify and treat spinal pain. On the basis of the imaging advances, the neuroanatomic findings, the chemical mediator discoveries and the reported nonoperative treatment successes, a new spine care paradigm began to evolve. The paradigm incorporated the focused use of corticosteroid injections and neuroablative procedures to facilitate the progression of functionally based rehabilitation programs. Additionally, injections were increasingly being used in an attempt to diagnose spinal pain generators more accurately. The focus shifted to one that promoted improved patient function as the pre-eminent outcome yardstick. Originally, there were very few spine specialists trained and experienced to perform spinal injections.
Jeffrey A. Saal, MD
As the popularity of injections grew, the need to train more physicians ensued. Anesthesia pain programs and physiatry training courses grew to meet this demand.
The present The treatment algorithm currently incorporates injection procedures to facilitate functional improvement. The concept is straightforward. If an inflammatory focus is present and can be incriminated as a dominant cause of the patient’s pain generation, then a precisely injected corticosteroid can be used to reduce the inflammation and permit progression of a physical rehabilitation program to enhance functional improvement and recovery. Simultaneously, surgeons are asking for more precise information regarding pain generation to plan operative interventions. Lumbar selective nerve injections, facet injections, medial branch dorsal ramus injections and diagnostic disc injections are used in many centers to sort out complex spinal pain patients. The growing demand for therapeutic and diagnostic injections has given birth to the injectionist (ie, the interventionist). This evolutionary phenomenon has led to a spread from the original core “values.” The interventionists have begun to use their procedures outside of the established algorithm. Multiple corticosteroid injections are being used in place of physical rehabilitation. Many patients are being treated with procedures and medications and are never exposed to rehabilitation efforts to improve function. Likewise, patients with “simple” back pain are undergoing facet rhizolysis procedures and discography at the top of the algorithm rather than at the originally intended later stages. “Shoot first, ask questions later” appears to be the prevailing motto. The number of injections performed on any individual patient was increased. One begins to see patients who have undergone 20 to 50 epidural injections. The cost of injection-based workups before surgery has increased to as high as $8,000 to 10,000, and it is not entirely clear that this has led to improved outcome. The proliferation of spine fusion to treat axial low back pain has led to the increased use of discography. However, as surgical failures are seen, discography has often been blamed as the culprit. It has been said that discography cannot predict the success of fusion surgery. Therefore, discography lacked specificity, and its benefits are questionable. This has raised further questions regarding the existence of symptomatic discogenic pain. The flaw in this reasoning is using a therapeutic intervention (especially one with mixed results) as the yardstick to measure the precision of a test finding or the presence of a diagnostic entity. Pain programs proliferated even further in an effort to absorb the chronic pain patients created by the spine care system. These developments have led to an increase in the use of injection procedures. Remarkably, this has all occurred during a time when there are no single randomized clinical trials validating the use of injection procedures or fusion surgery.
Editorial / The Spine Journal 1 (2001) 387–389
Inevitably, with procedure proliferation comes backlash. The lack of randomized trials to support injection therapy or injection pain localization has repeatedly been pointed out. Payers question the need for fluoroscopic localization and whether injections can affect the eventual outcome of the patient. Quality of life as it relates to pain relief and functional improvement are often ignored. Studies that evaluate injections as stand alone therapy often lead to questioning the effect of epidural and facet injections. Unfortunately, these studies have evaluated injections out of context to their intended use, because the intention of injection therapy is an adjunctive therapy to promote function-based rehabilitation. Many publicized studies have failed to test this hypothesis; instead they have tended to analyze injection procedures as a stand alone, all or none therapeutic intervention. Nihilists often state that because no one really knows where pain is coming from, injections, interventional diagnostics and fusion surgery are all useless. This has given license to the payers to shift spine care to general medicine physicians and deny access to specialists. A recent randomized clinical trial reported that epidural injections might help a significant number of patients avoid lumbar surgery. Studies validating thera-peutic facet injections, however, remain lacking, and there are no data to firmly support the use of selective epidural injections versus standard lumbar epidural injections. The future As we attempt to move the field forward, let us take a moment to look at questions raised from clinical experience using spinal injection procedures. In selected cases of lumbar disc herniation and spinal stenosis, epidural corticosteroid injections when coupled with physical rehabilitation may help promote recovery without surgery. In selected cases of lumbar spinal stenosis, selective nerve root block may be able to identify the offending spinal nerve. In select cases, the Z-joint complex may be identified as a pain generator, and neuroablative procedures may reduce pain from this source for a period of time. Selected patients with sacroiliac pain may be diagnosed with localized injection. Selected patients after motor vehicle accidents with cervical posterior ligamentous complex and facet joint injuries may be amenable to neuroablative procedures targeted at the offending dorsal ramus branch. Selected patients with discogenic pain may be identified by diagnostic disc injection (ie, discography). There is no one imaging marker that accurately and reproducibly identifies a painful disc, facet joint or any other spinal structure.
389
Psychological factors modify pain perception and should alter the interpretation of pain provocation diagnostic procedures. Poorly performed injection technique may increase and prolong a patient’s pain response. In order to improve the quality of spine care and injection procedures, future endeavors should include the following key elements: A return to patient-centered care that promotes functional optimization through the least invasive and risky therapeutic intervention available to that particular patient at that point in time. This should take into consideration the diagnosis, the degree of impairment and the level of chronicity. An effort to improve the clinical abilities of interventionists. This should include physical examination skills, and the prescription and monitoring of the rehabilitation program. Alternatively, interventionists should work in conjunction with skilled clinicians to handle the care of the patient before and beyond the intervention. The future of injection therapy will be predicated upon ongoing research efforts, which should include: Research to investigate the ability of injection procedures to improve patient outcomes; Research to investigate the ability of injection procedures to precisely, reproducibly and accurately identify spinal pain generators; Research to evaluate the efficacy of varying doses of different preparations of corticosteroids; Research to evaluate the value of precise epidural localization of medication in the various categories and types of disc herniations and spinal stenosis; Research to evaluate the true incidence and natural history of painful internal disc derangement; Research to determine the combined impact of exercise and injection efforts on the treatment of the various categories of painful spinal disorders; The discovery of new agents to specifically block the chemical mediators of pain and inflammation; Discovery of specific imaging markers of pain. The bottom line should be very clear. Our role as spine care practitioners is to improve our patients’ health and well being. Sometimes this path has potholes and pitfalls. In the ideal world all of the medicine we practice will be evaluated by RCTs. However, in the present real world, physician judgment is still required. Judgment can be defined as the making of a decision based on facts that are not clearly in evidence. Therefore, we must sharpen our judgment and never lose sight of the target, our patient.