Percutaneous Peripheral Nerve Stimulation of the Medial Branch Nerves for the Treatment of Chronic Axial Back Pain in Patients After Radiofrequency Ablation.

OBJECTIVE: Lumbar radiofrequency ablation is a commonly used intervention for chronic back pain. However, the pain typically returns, and though retreatment may be successful, the procedure involves destruction of the medial branch nerves, which denervates the multifidus. Repeated procedures typically have diminishing returns, which can lead to opioid use, surgery, or implantation of permanent neuromodulation systems. The objective of this report is to demonstrate the potential use of percutaneous peripheral nerve stimulation (PNS) as a minimally invasive, nondestructive, motor-sparing alternative to repeat radiofrequency ablation and more invasive surgical procedures. DESIGN: Prospective, multicenter trial. METHODS: Individuals with a return of chronic axial pain after radiofrequency ablation underwent implantation of percutaneous PNS leads targeting the medial branch nerves. Stimulation was delivered for up to 60 days, after which the leads were removed. Participants were followed up to 5 months after the start of PNS. Outcomes included pain intensity, disability, and pain interference. RESULTS: Highly clinically significant (≥50%) reductions in average pain intensity were reported by a majority of participants (67%, n = 10/15) after 2 months with PNS, and a majority experienced clinically significant improvements in functional outcomes, as measured by disability (87%, n = 13/15) and pain interference (80%, n = 12/15). Five months after PNS, 93% (n = 14/15) reported clinically meaningful improvement in one or more outcome measures, and a majority experienced clinically meaningful improvements in all three outcomes (i.e., pain intensity, disability, and pain interference). CONCLUSIONS: Percutaneous PNS has the potential to shift the pain management paradigm by providing an effective, nondestructive, motor-sparing neuromodulation treatment.

Treatment of chronic axial back pain with 60-day percutaneous medial branch PNS: Primary end point results from a prospective, multicenter study.

BACKGROUND: The objective of this prospective, multicenter study is to characterize responses to percutaneous medial branch peripheral nerve stimulation (PNS) to determine if results from earlier, smaller single-center studies and reports were generalizable when performed at a larger number and wider variety of centers in patients recalcitrant to nonsurgical treatments. MATERIALS & METHODS: Participants with chronic axial low back pain (LBP) were implanted with percutaneous PNS leads targeting the lumbar medial branch nerves for up to 60 days, after which the leads were removed. Participants were followed long-term for 12 months after the 2-month PNS treatment. Data collection is complete for visits through end of treatment with PNS (primary end point) and 6 months after lead removal (8 months after start of treatment), with some participant follow-up visits thereafter in progress. RESULTS: Clinically and statistically significant reductions in pain intensity, disability, and pain interference were reported by a majority of participants. Seventy-three percent of participants were successes for the primary end point, reporting clinically significant (≥30%) reductions in back pain intensity after the 2-month percutaneous PNS treatment (n = 54/74). Whereas prospective follow-up is ongoing, among those who had already completed the long-term follow-up visits (n = 51), reductions in pain intensity, disability, and pain interference were sustained in a majority of participants through 14 months after the start of treatment. CONCLUSION: Given the minimally invasive, nondestructive nature of percutaneous PNS and the significant benefits experienced by participants who were recalcitrant to nonsurgical treatments, percutaneous PNS may provide a promising first-line neurostimulation treatment option for patients with chronic axial back pain.

Allogeneic Disc Progenitor Cells Safely Increase Disc Volume and Improve Pain, Disability, and Quality of Life in Patients With Lumbar Disc Degeneration-Results of an FDA-Approved Biologic Therapy Randomized Clinical Trial.

BACKGROUND: Progenitor cells derived from intervertebral disc tissue demonstrated immunomodulatory and regenerative properties in preclinical studies. We report the safety and efficacy results of a US Food and Drug Administration-approved clinical trial of these cells for the treatment of symptomatic degenerative disc disease. METHODS: Sixty patients with symptomatic single-level lumbar degenerative disc disease (mean age 37.9 years, 60% men) were enrolled in a randomized, double-blinded, placebo-controlled Phase I/Phase II study at 13 clinical sites. They were randomized to receive single intradiscal injections of either low-dose cells (N = 20), high-dose cells (N = 20), vehicle alone (N = 10), or placebo (N = 10). The primary endpoint was mean visual analog scale (VAS) pain improvement >30% at 52 weeks. Disc volume was radiologically assessed. Adverse events (AEs), regardless of whether they were related to treatment, were reported. Patients were assessed at baseline and at 4, 12, 26, 52, 78, and 104 weeks posttreatment. RESULTS: At week 52, the high-dose group had a mean VAS percentage decrease from baseline (-62.8%, P = 0.0005), achieving the endpoint of back pain improvement >30%; the mean change was also significantly greater than the minimal clinically important difference of a 20-point decrease (-42.8, P = 0.001). This clinical improvement was maintained at week 104. The vehicle group had a smaller significant decrease in VAS (-52.8%, P = 0.044), while the low-dose and placebo groups showed nonsignificant improvements. Only the high-dose group had a significant change in disc volume, with mean increases of 249.0 mm3 (P = 0.028) at 52 weeks and 402.1 mm3 (P = 0.028) at 104 weeks. A minority of patients (18.3%) reported AEs that were severe. Overall, 6.7% of patients experienced serious AEs, all in the vehicle (n = 1) or placebo (n = 3) groups, none treatment related. CONCLUSIONS: High-dose allogeneic disc progenitor cells produced statistically significant, clinically meaningful improvements in back pain and disc volume at 1 year following a single intradiscal injection and were safe and well tolerated. These improvements were maintained at 2 years post-injection. CLINICAL TRIAL REGISTRATION: NCT03347708-Study to Evaluate the Safety and Preliminary Efficacy of Injectable Disc Cell Therapy, a Treatment for Symptomatic Lumbar Intervertebral Disc Degeneration.

Multivariable analyses of the relationships between age, gender, and body mass index and the source of chronic low back pain.

OBJECTIVE: To examine the combined relationships between age, gender, and body mass index (BMI) and the specific source of chronic low back pain. DESIGN: Retrospective chart review. SETTING: University spine center. PATIENTS: Charts from 378 cases from 358 consecutive patients were reviewed and 157 independent cases from 153 patients who underwent definitive diagnostic injections were analyzed. INTERVENTIONS: Discography, dual diagnostic facet joint blocks, sacroiliac joint injections, anesthetic interspinous ligaments/opposing spinous processes/posterior fusion hardware injections, percutaneous augmentation. OUTCOME MEASURES: Chronic low back pain source was the primary outcome variable. Predictor variables included age at initial presentation, gender, and BMI. RESULTS: Age, gender, and BMI were each significantly associated with the source of chronic low back pain, after controlling for the effects of each other. Increases in age were associated with significant decreases in the odds of internal disc disruption (IDD) vs facet joint pain (FJP), sacroiliac joint pain (SIJP), and other sources and decreases in the odds of FJP and SIJP vs other sources. Being female was associated with significant increases in the odds of SIJP vs IDD, FJP, and other sources. Increased BMI was associated with significant increases in the odds of FJP vs SIJP. CONCLUSIONS: These findings suggest a significant relationship among gender, age, and BMI and structural causes of chronic low back pain. Lumbar IDD is more prevalent in young males while FJP is more prevalent in females with increased BMI. Female gender and low BMI are associated with SIJP.

Comparison of four different analgesic discogram protocols comparing the incidence of reported pain relief following local anesthetic injection into concordantly painful lumbar intervertebral discs.

OBJECTIVE: To compare the incidence of pain relief following injection of local anesthetic (LA) into lumbar discs that caused concordant pain during provocation testing. DESIGN: Prospective collected data review from two centers and compare with published results. OUTCOME MEASURES: We compared subjective reported pain relief following provocative testing using the following protocols at three separate facilities: 23 patients undergoing routine provocative discography using contrast alone (PD); 47 patients undergoing provocative discography performed using an equal combination of LA and contrast (CPD); 120 patients injected with LA following routine PD (ADPD); 33 patients undergoing stand-alone analgesic discography (SAAD); and 28 patients injected with LA through a catheter (FAD) placed during provocative discogaphy testing. RESULTS: Pressure-controlled PD showed a positive response rate of 34% per disc in patients with a clinical diagnosis of discogenic pain. None of the PD group without LA had pain relief and less than 10% of the CPD group reported pain relief. Forty percent of the SAAD group with positive pain reproduction reported ≥50% relief and 20% reporting ≥80% relief. Forty-six percent of the ADPD group reported ≥50% relief and 30% reporting ≥80% relief. The FAD group had a greater 80% patients reporting ≥50% pain relief although fewer 26% reporting more convincing ≥80% relief. CONCLUSIONS: If the criterion standard to confirm painful annular tears is concordant pain provocation and 80% or greater pain relief following LA injected into lumbar discs, the SAAD, ADPD, and FAD protocols show statistically similar 20% to 30% prevelance.

Effect of age on outcomes after allogeneic disc tissue supplementation in patients with chronic discogenic low back pain in the VAST trial.

Aim: To explore the effects of viable allogeneic disc tissue supplementation in younger patients with discogenic chronic low back pain (CLBP). Patients & methods: VAST was a randomized placebo-controlled trial of disc allograft supplementation in 218 patients with discogenic CLBP. We conducted a post hoc analysis of change from baseline to 12 months in Oswestry Disability Index (ODI) and visual analog scale for pain intensity scores stratified by patient age. Results: Patients aged <42 years receiving allograft experienced greater improvement in ODI (p = 0.042) and a higher ODI response rate (≥10-, ≥15- and ≥20-point reductions in ODI) than those receiving saline (p = 0.001, p = 0.002 and p = 0.021, respectively). Conclusion: Young patients with discogenic CLBP may have significant functional improvement following nonsurgical disc allograft supplementation.

The VAST trial evaluated a new treatment for patients with chronic back pain resulting from one or two degenerated spinal discs. The treatment consists of a single injection of disc tissue supplement. A total of 218 adults participated in the study; most received the active treatment, while a smaller number (39 patients) received an injection of saline. In this paper we explain what happened over the 12 months after the injections. Patients who were younger (<42 years old) experienced more functional benefits (i.e., ability to perform daily tasks) after active treatment compared with those who received the saline injection, as measured by disability score. In contrast, older patients (≥42 years old) experienced functional benefits with both active and saline treatments, with no differences between the groups. There were more side effects in both age groups in those who received the active treatment compared with those who received saline, but almost all of the side effects were temporary and not serious. Clinical Trial Registration number: NCT03709901 (ClinicalTrials.gov).

What is the source of chronic low back pain and does age play a role?

OBJECTIVE: The objective of this study was to estimate the prevalence, mean age, and association of prevalence and age of lumbar internal disc disruption (IDD), facet joint pain (FJP), sacroiliac joint pain (SIJP), spinal and pelvic insufficiency fractures, interspinous ligament injury/Baastrup's Disease, and soft tissue irritation by fusion hardware. DESIGN: The study's design was a retrospective chart review. SETTING: The study was set in an academic spine center. PATIENTS: A total of 378 cases from 358 patients were reviewed of which 170 cases from 156 patients who underwent diagnostic procedures were included. INTERVENTIONS: Discography, dual diagnostic facet joint blocks, intra-articular sacroiliac joint injections, anesthetic injections of painful interspinous ligaments/opposing spinous processes/posterior fusion hardware, or percutaneous augmentation were performed. OUTCOME MEASURES: Prevalence and age were analyzed for each diagnosis group. METHODS: Patients with recalcitrant low back pain underwent diagnostic procedures based on their clinical presentation until the pain source was identified. RESULTS: The prevalence of internal disc disruption, facet joint pain and sacroiliac joint pain was 42%, 31%, and 18%, respectively. Patients with internal disc disruption were significantly younger than those with facet joint pain or sacroiliac joint pain. Increased age was associated with a decreased probability of internal disc disruption and increased probabilities of facet joint pain and sacroiliac joint pain as the source of low back pain until approximately age 70. CONCLUSION: Our data confirm the intervertebral disc as the most common etiology of chronic low back pain in adults. Based on our sample, the younger the patient, the more likely low back pain is discogenic in origin. Facetogenic or sacroiliac joint pain is more likely in older patients.

Etiology of chronic low back pain in patients having undergone lumbar fusion.

OBJECTIVE: To estimate the prevalence of lumbar internal disc disruption, zygapohyseal joint pain, sacroiliac joint pain, and soft tissue irritation by fusion hardware in post-fusion low back pain patients compared with non-fused patients utilizing diagnostic spinal procedures. DESIGN: Retrospective chart review. SETTING: University spine center. PATIENT SAMPLE: Patients presenting to a community-based, multidisciplinary, academic spine center (65.9% female, mean age 54.4 years, median pain duration 12 months). INTERVENTIONS: Charts of consecutive low back pain cases completing diagnostic spinal procedures including provocation discography and zygapohyseal joint, sacroiliac joint, and fusion hardware blockade were retrospectively reviewed. OUTCOME MEASURES: Based on the results of discography and/or diagnostic blockades, subjects were classified with internal disc disruption, zygapohyseal joint pain, sacroiliac joint pain, or fusion hardware related pain. RESULTS: The diagnoses of 28 fusion cases identified from 170 low back pain patients undergoing diagnostic procedures included 12 with sacroiliac joint pain, seven with internal disc disruption, five with zygapohyseal joint pain, and four due to soft tissue irritation from fusion hardware. No significant differences were noted in zygapohyseal joint mediated pain with and without fusion history. Mean ages of patients were similar with and without fusion history for cases diagnosed as internal disc disruption. CONCLUSION: In patients' recalcitrant to non-interventional care, the sacroiliac joint is the most likely source of low back pain after lumbar fusion followed by internal disc disruption, zygapohyseal joint pain, and soft tissue irritation due to fusion hardware. Sacroiliac joint pain is more common after fusion, while internal disc disruption is more common in non-fusion patients.

Use of Bone Marrow Concentrate to Treat Pain and Musculoskeletal Disorders: An Academic Delphi Investigation.

BACKGROUND: Acute and degenerative musculoskeletal disorders are among the most common etiologies of disability worldwide. Recently, there has been interest in the field of regenerative medicine to bridge the gap between conservative and surgical management of these conditions. Autologous bone marrow concentrate is one type of injectate that has increased in popularity over the last few decades. Though there is promising evidence supporting its efficacy, standard of care practice guidelines to govern the appropriate use and implementation of such technology are currently lacking. OBJECTIVES: The aim of this article is to report findings from a survey administered using the Delphi technique to a group of physicians using bone marrow concentrate in practice to determine best practice consensus regarding optimization of patient safety and education. STUDY DESIGN: Delphi panel technique. SETTING: The study was first announced at a national meeting and continued remotely across the United States via 4 rounds of online surveys. METHODS: An initial panel of 30 expert members was convened and a 5-member steering committee was established. Four rounds of consensus questionnaires totaling 11 unique questions were distributed. Ten questions included a 5-point Likert scale from "Strongly Agree" to "Strongly Disagree," and one question had a selection of 5 options regarding minimum level of evidence required. The anonymized aggregate results of each round were shared with the group prior to voting in the subsequent round in accordance with the Delphi process. Consensus was defined as 80% agreement of the statements indicating either "Strongly Agree" or "Agree" for the 10 questions with the Likert Scale and 80% agreement among 2 of 5 choices in the question regarding levels of evidence. RESULTS: Three invited participants were excluded by the second round of questions due to lack of response in a timely manner, leaving 27 physicians queried. Nine of the 11 questions met criteria for > 80% consensus. Areas of agreement included importance of a treatment registry, candidacy grading, expanded informed consent, scientific accuracy in advertising, institutional review board approval for novel uses, performance of procedures by only licensed physicians or mid-level providers with direct physician oversight, use of image guidance for injections, data submission for publication in peer reviewed literature, and a minimum requirement of case-series level of evidence for use of bone marrow concentrate in musculoskeletal medicine. The 2 areas that did not meet criteria for consensus included online publishing of individual clinic data and standards around cell counting for dosing. LIMITATIONS: The Delphi panel of experts was convened on a voluntary basis rather than a nomination process. Our panel of experts were all physicians who use bone marrow concentrate in practice, therefore it is possible that a different panel of experts within other disciplines would reach different conclusions. CONCLUSIONS: There is significant consensus among a panel of physicians performing bone marrow concentrate injections regarding best practice guidelines for musculoskeletal conditions.

Are outer annular fissures stimulated during diskography the source of diskogenic low-back pain? An analysis of analgesic diskography data.

OBJECTIVE: This study aimed to clarify whether painful annular fissures stimulated during provocation diskography are the likely source of diskogenic pain. DESIGN: A retrospective analysis was conducted of prospectively collected data. SETTING: Multidisciplinary, academic spine center. PATIENTS: The study was completed in a cohort of 28 consecutive patients were enrolled presenting with 6 months duration of axial low-back pain recalcitrant to physical therapy, oral analgesics, and epidural steroid injections and who have diskogenic pain based on history, exam, magnetic resonance imaging, and diskography. INTERVENTIONS: Subjects underwent provocation diskography and analgesic diskography utilizing a balloon-tipped intradiskal catheter allowing intradiskal injection of anesthetic. OUTCOME MEASURES: Visual analog scale, finger-to-floor distance were utilized as outcome measures. RESULTS: 80% of painful intervertebral disks as detected by provocation diskography were sufficiently anesthetized resulting in >50% reduction in low-back pain during analgesic diskography. CONCLUSION: Diskogenic pain is in varying degrees caused by the sensitized nociocepters within annular tears.

Evidence-informed management of chronic low back pain with epidural steroid injections.

The management of chronic low back pain (CLBP) has proven very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing amongst available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to chronic low back pain, the North American Spine Society has sponsored this special focus issue of The Spine Journal, titled Evidence-Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP.

Percutaneous sacroplasty for osteoporotic sacral insufficiency fractures: a prospective, multicenter, observational pilot study.

BACKGROUND CONTEXT: Sacral insufficiency fractures (SIFs) can cause low back pain in osteoporotic patients. Symptomatic improvement may require up to 12 months. Treatment includes limited weightbearing and bed rest, oral analgesics, and sacral corsets. Significant mortality and morbidity are associated with pelvic insufficiency fractures. Percutaneous injection of polymethylmethacrylate (PMMA) into the fractured ala, sacroplasty, is an alternative treatment for SIF patients. Under fluoroscopic control, 13-G bone trochars are inserted into the fractured ala while the patient is maintained under conscious sedation. Initial reports have documented safe and effective performance of sacroplasty. Yet, these uncontrolled findings do not allow any precision in estimating complication rates or expected outcome. PURPOSE: Assess rates of complications and observe outcomes after sacroplasty in a medium-sized uncontrolled cohort of SIF patients. STUDY DESIGN/SETTING: A prospective observational cohort study of consecutive osteoporotic SIF patients. PATIENT SAMPLE: Consecutive, osteoporotic patients with symptomatic SIFs electing to enter the study. OUTCOME MEASURES: Visual Analogue Scale (VAS) score, analgesic utilization, and patient satisfaction. METHODS: Baseline VAS rating, analgesic usage, and duration of symptoms were recorded. Subsequent VAS ratings were assessed within 30 minutes after the procedure, at 2-, 4-, 12-, 24-, and 52-week postprocedure. Analgesic usage and patient satisfaction were assessed at final follow-up. Each procedure was performed under light intravenous conscious sedation using fluoroscopy. Two bone trochars were inserted between the sacral foramen and sacroiliac joint through which 2 to 3 cc of PMMA were injected. RESULTS: Fifty-two patients, 40 females, were treated. The mean age was 75.9 years with a mean symptom duration of 34.5 days. All patients were available at each follow-up interval except one patient who died because of unrelated pulmonary disease before the 4-week follow-up. The mean VAS score at baseline was 8.1 and 3.4 within 30 minutes after the procedure, 2.5 at 2, 2.1 at 4, 1.7 at 12, 1.4 at 24, and 0.8 at 52 weeks. Improvement was statistically significant using a repeated measures single-factor analysis of variance. One case of transient S1 radiculitis occurred but resolved completely with one transforaminal epidural steroid injection. CONCLUSIONS: Sacroplasty for SIF appears to be associated with rapid and sustained pain relief in most patients with few complications. More rigorous trials are warranted to provide definitive evidence of the safety and efficacy of sacroplasty for SIFs.

Cervical disc degeneration and neck pain.

Cervical intervertebral disc has long been considered a common source of neck pain. However, the pain caused by the disc itself has not been clearly defined so far, and its diagnosis and treatment has always been controversial. Degenerative cervical disc has a rich supply of nerve fibers, is prone to inflammatory reactions, and is susceptible to pain that can be provoked by disc stimulation or distention, and can be eliminated by block. Overwhelming clinical evidence demonstrates that neck pain in patients with degenerative cervical radiculopathy or myelopathy can be subsided rapidly by anterior cervical surgery, further indicating that this neck pain stems from the pathology of cervical disc itself. Cervical discography is advocated as the only test that connects disease to symptoms, but the procedure remains controversial. If strict criteria and technique are maintained, discography can discriminate painful, symptomatic discs from nonpainful, asymptomatic discs. Discogenic neck pain alone without cervical disc herniation or cervical spondylosis accounts for a large proportion of chronic neck pain. For these patients who continue to have refractory neck pain and fail to respond to conservative treatment, anterior cervical fusion surgery or artificial cervical disc replacement may be a better choice, and preoperative cervical discography can guarantee the excellent surgical results. Existing basic and clinical studies have scientifically shown that cervical intervertebral disc degeneration can lead to neck pain.

Nonspondylolytic etiologies of lumbar pain in the young athlete.

Approximately 50% of adolescent athletes with persistent lumbar pain can be diagnosed with spondylolysis or spondylolisthesis. The remaining 50% will have suffered injury of the vertebral body, intervertebral disc, ring apophysis, pelvis, articular processes, spinous processes, interspinous ligament, or other soft tissues of the lumbar spine. The adolescent spine is prone to these injuries as a consequence of the growth spurt and skeletal immaturity. Accurate diagnosis is mandatory in order to achieve successful treatment. History, physical examination, imaging modalities, and precision spinal injections can be employed to accurately diagnose the source of the symptoms. Appropriate treatment measures can then be prescribed to optimally treat the adolescent spine injury.

Cellular supplementation technologies for painful spine disorders.

Low back pain affects more than 80% of adults. A proportion of these adults develops chronic low back pain (CLBP) and becomes disabled by their condition. CLBP is expensive to diagnose and treat and in terms of associated loss of productivity in the work place setting by affected individuals. Although challenging, the source of CLBP can be identified. Contemporary literature contains several studies that have established prevalence estimates for various structural sources of CLBP. In young adults, the intervertebral disk is a common source of CLBP, once it incurs annular injury that heals incompletely. Effective treatment for painful disks currently is an unmet clinical need. In older adults, the facet and sacroiliac joints are more commonly responsible for CLBP. Although certain minimally invasive techniques do exist for these painful joints, an effective restorative intervention has yet to be established. Annular injury precipitates a physiologic response that can lead to a catabolic state within the disk that impairs disk restoration. Cell loss is a feature of this process as well as the pathophysiology associated with painful facet and sacroiliac joints. Cellular supplementation is an attractive treatment strategy to initiate the repair of an injured lumbosacral structure. The introduction of exogenous cells may lead to increased extracelluar matrix production and reduced pain and disability in diskogenic CLBP. Compelling data in animal studies have been produced, stimulating Food and Drug Administration-regulated trials in humans. Numerous questions remain regarding cell viability and sufficient native nutrients to support these cells. Clinical research protocols have focused predominantly on diskogenic CLBP, and very few have addressed painful facet and/or sacroiliac joints.