Thoracic Medial Branch Research Articles

Investigation of the anatomical course of articular branches to the thoracic zygapophysial joints

BackgroundRecent studies have questioned the validity of targeting the thoracic medial branch via anesthetic blocks or radiofrequency neurotomy for the diagnosis or treatment of pain from the thoracic zygapophysial joints. PurposeTo define the origin and course of the articular branches to the thoracic zygapophysial joints at all levels. DesignCadaveric dissection. SettingThe Gross Anatomy Laboratory at the University of New England College of Osteopathic Medicine. SubjectsOne cadaveric thoracic spine. MethodsGross and stereoscopic dissection of the bilateral dorsal rami T1–T12 was performed on one embalmed cadaver. The medial and lateral branches were traced from their cutaneous distribution to the origin at the dorsal ramus. The articular branches were identified using stereoscopic dissection by tracing their origin from the dorsal ramus or medial branch to the capsule of the zygapophysial joint. The images were recorded using digital photography. ResultsTwenty-two of the twenty-four articular branches were identified in a single cadaveric specimen. Articular branches at T7 on the right side and T9 on the left side were not identified. 5 of the 22 (18%) articular branches were observed to arise from the proximal segment of the medial branch of the dorsal ramus. Of the remainder, 17 of the 22 (78%) articular branches were observed to arise from the dorsal primary ramus itself. At levels T1-9, the articular branch coursed inferiorly along the lamina to reach the joint capsule. At levels T10-T12, the articular branch traversed the intervertebral foramen to reach the facet joint. The T12 medial branch on the left was seen to travel inferior to innervate the L1/L2 zygapophysial joint. ConclusionThe source of the innervation for the thoracic zygapophysial is variable and can arise from the dorsal ramus itself or from the proximal segment of the medial branch. Unlike the cervical and lumbar medial branches, which innervate two joints each, in this case, the thoracic dorsal rami appear to innervate only the zygapophysial joint at the level of the nerve exit. It should be noted that the findings may be limited in their generalizability due to the reliance on a single cadaver study.

Ultrasound-guided procedures for the management of chronic thoracic back pain: a technical review.

Pain arising from the thoracic region has been reported to be potentially as debilitating as cervical or lumbar back pain, and may stem from a vast number of spinal sources, including zygapophysial, costovertebral and costotransverse joints, intervertebral discs, ligaments, fascia, muscles, and nerve roots. Over the last two decades, the use of ultrasound in interventional spinal procedures has been rapidly evolving, due to the ultrasound capabilities of visualizing soft tissues, including muscle layers, pleura, nerves, and blood vessels, allowing for real-time needle tracking, while also reducing radiation exposure to both patient and physician, when compared to traditional fluoroscopy guidance. However, its limitations still preclude it from being the imaging modality of choice for some thoracic spinal procedures, notably epidural (interlaminar and transforaminal approaches) and intradiscal injections. In this technical review, we provide an overview of five thoracic spinal injections that are amenable to ultrasound guidance. We start by discussing their clinical utility, followed by the relevant topographic anatomy, and then provide an illustrated technical description of each of the procedures discussed: (1) erector spinae plane block; (2) intra-articular thoracic zygapophyseal (facet) joint injection; (3) thoracic medial branch block; (4) costotransverse joint injection; and (5) costovertebral joint injection.

ID:15924 Successful Treatment of T4 Syndrome With Thoracic Sympathetic Nerve Block: A Medically Complex Case

33-year-old man was referred for 10+ year history of intermittent right sided thoracic back pain, scapular stiffness and muscle spasms, as well as proximal right upper extremity pain. Pain described as spasms, throbbing, shooting, punishing and exhausting that lasts for days and occurs multiple times per week. Pain intensity was 6-8/10 on the numerical pain rating scale (NRS). Exercise exacerbates his symptoms. The patient failed previous conservative treatments and alternative therapies. No improvement with pain medications or previous interventional treatment including thoracic medial branch blocks and prolotherapy. Exam notable for tightness with radiation of the posterior shoulder girdle (between the thoracic spine and medial border of scapula), right biceps and into the first and second digits. Diagnostic testing including radiographs and CT were normal, ruling out musculoskeletal abnormalities. Cervical MRI demonstrated mild degenerative disc disease at C4-7, however thoracic MRI was within normal limits ruling out degenerative or discogenic etiology. EMG nerve conduction study was normal eliminating potential long thoracic nerve syndrome. After thorough evaluation and failing physical therapy costotransverse dysfunction was ruled out. Suspecting T4 syndrome, the patient underwent a diagnostic and therapeutic right T2 thoracic sympathetic block under fluoroscopic guidance.

Comparison of two needle versus one needle lesioning techniques for thoracic medial branch neurotomy

Background and objectivesNo prior studies have investigated an assumed advantage of creating a radiofrequency strip lesion for posterior element spinal axial pain using a two-needle technique (TNT) compared to a one-needle technique (ONT) that creates a single ovoid lesion. We explore the relationship of TNT compared to ONT on the magnitude and duration of pain relief following thoracic medial branch neurotomy (TMBN). MethodsThis study is a retrospective audit of consecutive patients treated with TMBN at a single site and interventionalist over ten years (2007–2017). All patients had undergone TMBN after failed conservative care and, with few exceptions, patient-reported ≥ 70% pain relief after thoracic medial branch block (TMBB). All patients had TMBN performed with a medial to lateral (MLA) radiofrequency cannula approach using either an ONT or TNT technique. We used parametric and nonparametric statistics and three levels of case analysis to assess for intergroup differences. ResultsThirty-five consecutive patients underwent their primary TMBN, and two underwent both on a subsequent repeat using the MLA approach, 19 using the ONT, 18 using the TNT. The TNT group had clinically and statistically greater pain relief magnitude and duration than the ONT subgroup. The difference resulted in non-overlapping 95% confidence intervals for both percent pain relief and duration of pain relief using three levels of case analysis. ConclusionThe comparison of TMBN techniques demonstrates a statistically significant separation of TNT to ONT sample mean values for magnitude and duration of pain relief when using TNT compared to ONT for TMBN using an MLA.

Combined thoracic medial branch radiofrequency and chemical neurotomy

ObjectiveExplore the effectiveness of thoracic medial branch neurotomy (MBN) using combined radiofrequency neurotomy and neurolytic lesioning. DesignA retrospective cohort of consecutive patients with chronic thoracic axial pain treated in a community setting. InterventionsWe included all patients who underwent MBN between 2010 and 2016, selected for MBN primarily based on 70% relief following single or dual diagnostic medial branch blocks. Using 18-gauge cannulas, we placed electrodes and made lesions at the suspected location of the thoracic medial branch based on anatomic knowledge at the time; the thermal lesions were supplemented with 50% dextrose to enhance the lesion radius. MeasuresWe defined success as ≥50% relief of their index thoracic pain not returning to baseline for at least six months. Patients not reached for follow-up were considered failures for worst-case analysis. ResultsTwenty-eight patients underwent an initial MBN between 2010 and 2016: Twenty-five of twenty-eight (89%) patients reported ≥70% pain reduction not returning to baseline for six months or longer. Using a worst-case analysis (WCA), patients reported average pain relief of 73% CI (63%,84%) with a mean duration of relief following the initial MBN of 9.9 months CI (6, 13.5). Seventeen of the initial 28 patients had a total of 31 repeat MBNs, 13/17 (76%) having pain relief reinstated after one or more repeat MBNs with an average duration of relief following a first repeat MBNs of 10.9 months CI (6.6,15.2). ConclusionThoracic MBN combined with a mild neurolytic is a potentially effective treatment for thoracic pain in patients selected with positive diagnostic MBB. There were no complications noted. One can reinstate pain relief with repeated MBN in most patients should their symptoms return.

Should a Coexisting or Suspected Diagnosis of Fibromyalgia Affect the Decision to Perform Diagnostic Blocks for Patients with Chronic Noncancer Pain — Results from an Observational Research Study

Diagnostic injections (blocks) are a valuable tool in the management of chronic noncancer pain. By precise blockade of specific neural structures and observation of pain responses, pain mechanisms can be accurately defined. With such information, therapeutic procedures targeting neural structures are possible. Fibromyalgia is a disorder of pain processing with characteristic symptoms. The 2010 American College of Rheumatologists fibromyalgia diagnostic criteria evaluates these symptoms in a scoring system, allowing more objectivity in the diagnosis. We hypothesize that patients with fibromyalgia phenotype fulfilling the 2010 American College of Rheumatologists criteria may respond to diagnostic blocks differently when compared to patients without fibromyalgia phenotype. This study was designed to establish whether diagnosis or suspected diagnosis of fibromyalgia should influence the decision to perform diagnostic blocks for chronic non-cancer pain. A prospective observational research study was performed at our institution. IRAS project ID: 231514. Tertiary pain clinic in the UK. Patients were selected to receive diagnostic block by usual clinical assessment after which they were asked to consent to take part in the study. All participating patients completed the 2010 American College of Rheumatologists fibromyalgia diagnostic questionnaire prior to the diagnostic block. Patients were divided into 2 groups A and B based on the outcome of block - primary outcome. Group A experienced a 70% or greater improvement in pain severity following the block for the anticipated duration of action of the local anesthetic, Group B experienced a less than 70% reduction in pain. Statistical analysis between groups A and B was conducted by comparing categorical data, described as percentages, with the chi squared test. Ordinal variables such as Widespread pain index and Symptom severity score are presented as median and analyzed with Mann-Whitney test. Seventy-seven patients were included in the study. Two patients were lost to follow-up. Of the 75 remaining patients, 44 received lumbar medial branch blocks, 19 genicular nerve blocks, 3 blocks to nerves supplying the sacroiliac joint, one suprascapular nerve block, and 6 cervical and 2 thoracic medial branch blocks. Group A contained 38 patients and group B contained 37 patients. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients between groups A (13 out of 38 patients) and B (13 out of 37 patients), P = 0.93. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients in subgroups undergoing the same type of diagnostic block (spinal pain and knee pain). Selection of patients prior to inclusion in the study may introduce bias. Patients were selected by individual treating clinicians using usual clinical practice; however, the exact selection criteria were not standardized. We conclude that after physician selection, the presence of fibromyalgia phenotype does not influence the outcome from diagnostic block. It is likely therefore that fibromyalgia phenotype should not influence the decision to perform diagnostic blocks if indicated based on assessment by an experienced pain physician.

Effect of Pulsed Radiofrequency Treatment on the Thoracic Medial Branch for Managing Chronic Thoracic Facet Joint Pain Refractory to Medial Branch Block with Local Anesthetics.

To evaluate the effect of pulsed radiofrequency (PRF) stimulation of the thoracic medial branch of the dorsal ramus in patients with chronic thoracic facet joint (TFJ) pain who were refractory to medial branch block (MBB). This was a prospective, observational study. The author retrospectively reviewed data from 72 patients who had received therapeutic MBB with 0.5 mL of 2% lidocaine mixed with 0.5 mL of 0.25% bupivacaine to treat TFJ-origin upper or midback pain. Of these patients, 20 were included to evaluate the effects of PRF on the thoracic medical branch to manage TFJ pain refractory to therapeutic MBB. PRF stimulation was administered at 5 Hz and a 5-millisecond pulsed width for 360 seconds at 45 V. The pain-reducing effect of the PRF procedure was evaluated via the numeric rating scale (NRS) at 1, 2, and 3 months after treatment. Successful pain relief was defined as ≥50% reduction in the NRS score compared with the score before treatment. The NRS scores changed significantly over time (pretreatment, 6.0 ± 1.0; 1 month, 3.3 ± 2.2; 2 months, 3.9 ± 2.1; and 3 months, 4.0 ± 2.2). At 1, 2, and 3 months after the PRF procedure, the NRS scores were significantly reduced compared with the scores before the treatment. Eleven (55%) of 20 patients reported successful pain relief at 3 months after PRF. The author suggests that PRF on the thoracic medial branch is an effective and safe interventional technique for the control of chronic TFJ pain.

Thoracic radiofrequency ablation

Thoracic spine pain is a relatively common condition. Pain in this region may be attributable to dysfunction of the thoracic facet joint. The true prevalence of thoracic facet pain remains somewhat elusive. Although challenging to diagnose at times, this joint is amenable to several therapeutic options. Radiofrequency neurotomy and thoracic medial branch blocks are normally used to treat facetogenic pain originating in the thoracic spine. Although demonstrating promise, larger, robustly designed trials are needed to further elucidate the appropriate treatment of this disorder.

An Update of Evaluation of Therapeutic Thoracic Facet Joint Interventions

Background: Chronic mid back and upper back pain caused by thoracic facet joints has been reported in 34% to 48% of patients based on responses to controlled diagnostic blocks. Systematic reviews have established moderate evidence for controlled comparative local anesthetic blocks of thoracic facet joints in the diagnosis of mid back and upper back pain, moderate evidence for therapeutic thoracic medial branch blocks, and limited evidence for radiofrequency neurotomy of thoracic medial branches. Study Design: Systematic review of therapeutic thoracic facet joint interventions. Objective: To determine the clinical utility of therapeutic thoracic facet joint interventions in the therapeutic management of chronic upper back and mid back pain. Methods: The available literature for the utility of facet joint interventions in the therapeutic management of thoracic facet joint pain was reviewed. The quality assessment and clinical relevance criteria utilized were the Cochrane Musculoskeletal Review Group criteria as utilized for interventional techniques for randomized trials and the criteria developed by the Newcastle-Ottawa Scale criteria for observational studies. The level of evidence was classified as good, fair, and limited (or poor) based on the quality of evidence developed by the U.S. Preventive Services Task Force (USPSTF). Data sources included relevant literature identified through searches of PubMed and EMBASE from 1966 to March 2012, and manual searches of the bibliographies of known primary and review articles. Outcome Measures: The primary outcome measure was pain relief (short-term relief = up to 6 months and long-term > 6 months). Secondary outcome measures were improvement in functional status, psychological status, return to work, and reduction in opioid intake. Results: For this systematic review, 13 studies were identified. Of these, 7 studies were excluded, and a total of 4 studies (after removal of duplicate publication) met inclusion criteria for methodological quality assessment with one randomized trial and 3 non-randomized studies. The evidence is fair for therapeutic thoracic facet joint nerve blocks, limited for thoracic radiofrequency neurotomy, and not available for thoracic intraarticular injections. Limitations: The limitation of this systematic review includes a paucity of literature. The only positive studies were of medial branch blocks performed by the same group of authors. Conclusion: The evidence for therapeutic facet joint interventions is fair for medial branch blocks, whereas it is not available for intraarticular injections, and limited for radiofrequency neurotomy due to lack of literature. Key words: Chronic thoracic pain, mid back or upper back pain, thoracic facet or zygapophysial joint pain, facet joint nerve blocks, medial branch blocks, therapeutic thoracic medial branch blocks, thoracic radiofrequency neurotomy, thoracic intraarticular facet joint injections

Complications of Fluoroscopically Directed Facet Joint Nerve Blocks: A Prospective Evaluation of 7,500 Episodes with 43,000 Nerve Blocks

Background: Chronic spinal pain is common along with numerous modalities of diagnostic and therapeutic interventions utilized, creating a health care crisis. Facet joint injections and epidural injections are the 2 most commonly utilized interventions in managing chronic spinal pain. While the literature addressing the effectiveness of facet joint nerve blocks is variable and emerging, there is paucity of literature on adverse effects of facet joint nerve blocks. Study Design: A prospective, non-randomized study of patients undergoing interventional techniques from May 2008 to December 2009. Setting: A private interventional pain management practice, a specialty referral center in the United States. Objectives: Investigation of the incidence in characteristics of adverse effects and complications of facet joint nerve blocks. The study was carried out over a period of 20 months including almost 7,500 episodes of 43,000 facet joint nerve blocks with 3,370 episodes in the cervical region, 3,162 in the lumbar region, and 950 in the thoracic region. All facet joint nerve blocks were performed under fluoroscopic guidance in an ambulatory surgery center by 3 physicians. The complications encountered during the procedure and postoperatively were evaluated prospectively. Methods: This study was carried out over a period of 20 months and included over 7,500 episodes or 43,000 facet joint nerve blocks. All of the interventions were performed under fluoroscopic guidance in an ambulatory surgery center by one of 3 physicians. The complications encountered during the procedure and postoperatively were prospectively evaluated. Outcomes Assessment: Measurable outcomes employed were intravascular entry of the needle, profuse bleeding, local hematoma, dural puncture and headache, nerve root or spinal cord irritation with resultant injury, and infectious complications. Results: There were no major complications. Multiple side effects and complications observed included overall intravascular penetration in 11.4% of episodes with 20% in cervical region, 4% in lumbar region, and 6% in thoracic region; local bleeding in 76.3% of episodes with highest in thoracic region and lowest in cervical region; oozing with 19.6% encounters with highest in cervical region and lowest in lumbar region; with local hematoma seen only in 1.2% of the patients with profuse bleeding, bruising, soreness, nerve root irritation, and all other effects such as vasovagal reactions observed in 1% or less of the episodes. Limitations: Limitations of this study include lack of contrast injection, use of intermittent fluoroscopy and also an observational nature of the study. Conclusion: This study illustrate that major complications are extremely rare and minor side effects are common. Key words: Spinal pain, facet joint nerve blocks, cervical medial branch or facet joint nerve blocks, thoracic medial branch or facet joint nerve blocks, lumbar facet joint nerve blocks, L5 dorsal ramus block complications

The Role of Thoracic Medial Branch Blocks in Managing Chronic Mid and Upper Back Pain: A Randomized, Double-Blind, Active-Control Trial with a 2-Year Followup

Study Design. A randomized, double-blind, active-control trial. Objective. To determine the clinical effectiveness of therapeutic thoracic facet joint nerve blocks with or without steroids in managing chronic mid back and upper back pain. Summary of Background Data. The prevalence of thoracic facet joint pain has been established as 34% to 42%. Multiple therapeutic techniques utilized in managing chronic thoracic pain of facet joint origin include medial branch blocks, radiofrequency neurotomy, and intraarticular injections. Methods. This randomized double-blind active controlled trial was performed in 100 patients with 50 patients in each group who received medial branch blocks with local anesthetic alone or local anesthetic and steroids. Outcome measures included the numeric rating scale (NRS), Oswestry Disability Index (ODI), opioid intake, and work status, at baseline, 3, 6, 12, 18, and 24 months. Results. Significant improvement with significant pain relief and functional status improvement of 50% or more were observed in 80% of the patients in Group I and 84% of the patients in Group II at 2-year followup. Conclusions. Therapeutic medial branch blocks of thoracic facets with or without steroids may provide a management option for chronic function-limiting thoracic pain of facet joint origin.

Poster 250 Should We Offer Thoracic Medial Branch Block Instead of Thoracic Vertebroplasty for Pain Management?

Poster 250 Should We Offer Thoracic Medial Branch Block Instead of Thoracic Vertebroplasty for Pain Management?

Comparative Effectiveness of a One-Year Follow-Up of Thoracic Medial Branch Blocks in Management of Chronic Thoracic Pain: A Randomized, Double-Blind Active Controlled Trial

Thoracic facet joints have been implicated as the source of chronic pain in the mid back or upper back in 34% to 42% of patients when the modified criteria of the International Association for the Study of Pain (IASP) is utilized. Various therapeutic techniques utilized in managing chronic thoracic pain of facet joint origin include intraarticular injections, medial branch blocks, and radiofrequency neurotomy of thoracic medial branch nerves. A randomized, double-blind, active controlled trial. A private practice, interventional pain management setting, and a specialty referral center setting in the United States. To determine the clinical effectiveness of therapeutic local anesthetic medial branch blocks with or without steroid in managing chronic function-limiting mid back or upper back pain of facet joint origin. The study was performed in an interventional pain management private practice, a tertiary referral center, in the United States. A total of 100 participants were included, with 50 participants in each of the local anesthetic and steroid groups. All of the participants met the diagnostic criteria of thoracic facet joint pain by means of comparative, controlled diagnostic blocks and the inclusion criteria. Group I participants received thoracic medial branch blocks with bupivacaine, whereas Group II participants received thoracic medial branch blocks with bupivacaine and non-particulate betamethasone. Outcomes measures included numeric rating scores (NRS), Oswestry Disability Index (ODI), opioid intake, and return to work status at baseline, 3 months, 6 months, and 12 months. Significant pain relief was defined as >/= 50% pain relief and/or a positive change in ODI scores. In Group I and Group II 90% of participants showed significant pain relief and functional improvement at 12 months. The majority of the participants experienced significant pain relief of 47.2 ± 10.1 weeks in Group I and 46.3 ± 8.4 weeks in Group II, requiring approximately 3.5 treatments per year with an average relief of 15.8 ± 10.5 in Group I and 13.6 ± 3.6 weeks in Group II per episode of treatment. Study limitations include the lack of a placebo group. Therapeutic thoracic medial branch blocks, with or without steroid, may provide a management option for chronic function-limiting mid back or upper back pain of facet joint origin. NCT00355706.

Systematic Review of Diagnostic Utility and Therapeutic Effectiveness of Thoracic Facet Joint Interventions

Chronic mid back and upper back pain caused by thoracic facet joints has been reported in 34% to 48% of the patients based on the responses to controlled diagnostic blocks. Systematic reviews have established moderate evidence for controlled comparative local anesthetic blocks of thoracic facet joints in the diagnosis of mid back and upper back pain, moderate evidence for therapeutic thoracic medial branch blocks, and limited evidence for radiofrequency neurotomy of therapeutic facet joint nerves. To determine the clinical utility of diagnostic and therapeutic thoracic facet joint interventions in diagnosing and managing chronic upper back and mid back pain. Systematic review of diagnostic and therapeutic thoracic facet joint interventions. Review of the literature for utility of facet joint interventions in diagnosing and managing facet joint pain was performed according to the Agency for Healthcare Research and Quality (AHRQ) criteria for diagnostic studies and observational studies and the Cochrane Musculoskeletal Review Group criteria as utilized for interventional techniques for randomized trials. The level of evidence was classified as Level I, II, or III based on the quality of evidence developed by United States Preventive Services Task Force (USPSTF) for therapeutic interventions. Recommendations were based on the criteria developed by Guyatt et al. Data sources included relevant literature of the English language identified through searches of Medline and EMBASE from 1966 to July 2008 and manual searches of bibliographies of known primary and review articles. Results of the analysis were performed for diagnostic and therapeutic interventions separately. For diagnostic interventions, studies must have been performed utilizing controlled local anesthetic blocks. For therapeutic interventions, the primary outcome measure was pain relief (short-term relief = up to 6 months and long-term relief > 6 months) with secondary outcome measures of improvement in functional status, psychological status, return to work, and reduction in opioid intake. Based on the controlled comparative local anesthetic blocks, the evidence for the diagnosis of thoracic facet joint pain is Level I or II-1. The evidence for therapeutic thoracic medial branch blocks is Level I or II-1. The recommendation is IA or 1B/strong for diagnostic and therapeutic medial branch blocks. The evidence for the diagnosis of thoracic facet joint pain with controlled comparative local anesthetic blocks is Level I or II-1. The evidence for therapeutic facet joint interventions is Level I or II-1 for medial branch blocks. Recommendation is 1A or 1B/strong for diagnostic and therapeutic medial branch blocks.

Reassessment of Evidence Synthesis of Occupational Medicine Practice Guidelines for Interventional Pain Management

Background: Appropriately developed practice guidelines present statements of best practice based on a thorough evaluation of the evidence from published studies on the outcomes of treatments, which include the application of multiple methods for collecting and evaluating evidence for a wide range of clinical interventions and disciplines. However, the guidelines are neither infallible, nor a substitute for clinical judgment. While the guideline development process is a complex phenomenon, conflict of interest in guideline development and inappropriate methodologies must be avoided. It has been alleged that the guidelines by the American College of Occupational and Environmental Medicine (ACOEM) prevent injured workers from receiving the majority of medically necessary and appropriate interventional pain management services. An independent critical appraisal of both chapters of the ACOEM guidelines showed startling findings with a conclusion that these guidelines may not be applied in patient care as they scored below 30% in the majority of evaluations utilizing multiple standardized criteria. Objective: To reassess the evidence synthesis for the ACOEM guidelines for the low back pain and chronic pain chapters utilizing an expanded methodology, which includes the criteria included in the ACOEM guidelines with the addition of omitted literature and application of appropriate criteria. Methods: For reassessment, randomized trials were utilized as it was in the preparation of the guidelines. In this process, quality of evidence was assessed and recommendations were made based on grading recommendations of Guyatt et al. The level of evidence was determined utilizing the quality of evidence criteria developed by the U.S. Preventive Services Task Force (USPSTF), as well as the outdated quality of evidence criteria utilized by ACOEM in the guideline preparation. Methodologic quality of each individual article was assessed utilizing the Agency for Healthcare Research and Quality (AHRQ) methodologic assessment criteria for diagnostic interventions and Cochrane methodologic quality assessment criteria for therapeutic interventions. Results: The results of reassessment are vastly different from the conclusions derived by the ACOEM guidelines. The differences in strength of rating for the diagnosis of discogenic pain by provocation discography and facet joint pain by diagnostic facet joint nerve blocks is established with strong evidence. Therapeutic cervical and lumbar medial branch blocks and radiofrequency neurolysis, therapeutic thoracic medial branch blocks, cervical interlaminar epidural steroid injections, caudal epidural steroid injections, lumbar transforaminal epidural injections, percutaneous and endoscopic adhesiolysis, and spinal cord stimulation qualified for moderate to strong evidence. Additional insight is also provided for evidence rating for intradiscal electrothermal therapy (IDET), automated percutaneous disc decompression, and intrathecal implantables. Conclusion: The reassessment and reevaluation of the low back and chronic pain chapters of the ACOEM guidelines present results that are vastly different from the published and proposed guidelines. Contrary to ACOEM’s conclusions of insufficient evidence for most interventional techniques, the results illustrate moderate to strong evidence for most diagnostic and therapeutic interventional techniques. Key words: Guidelines, evidence-based medicine, systematic reviews, ACOEM, interventional pain management, interventional techniques, guideline development, workers’ compensation, chronic pain guidelines, low back pain guidelines

Effectiveness of Thoracic Medial Branch Blocks in Managing Chronic Pain: A Preliminary Report of a Randomized, Double-Blind Controlled Trial; Clinical Trial NCT00355706

Background: Thoracic facet joints have been implicated as the source of chronic pain in the mid back or upper back in 34% to 48% of the patients. Various therapeutic techniques utilized in managing chronic thoracic pain of facet joint origin include intraarticular injections, medial branch blocks, and radiofrequency neurotomy of thoracic facet joint nerves. Objective: To determine the clinical effectiveness of therapeutic local anesthetic medial branch blocks with or without steroid in managing chronic function-limiting mid back or upper back pain of facet joint origin. Design: A randomized, double-blind, controlled trial. Setting: An interventional pain management private practice, a tertiary referral center, in the United States. Methods: A total of 48 patients were included, with 24 patients in each of the local anesthetic and steroid groups. All of the patients met the diagnostic criteria of thoracic facet joint pain by means of comparative, controlled diagnostic blocks and the inclusion criteria. Group I patients received thoracic medial branch blocks with bupivacaine, whereas Group II patients received thoracic medial branch blocks with bupivacaine and non-particulate betamethasone. Outcome Measures: Numeric pain scores (NRS), Oswestry Disability Index (ODI), opioid intake, and return to work status. All outcomes were assessed at baseline, 3 months, 6 months, and 12 months. Significant pain relief was defined as > 50% pain relief. Significant functional improvement was defined as 40% reduction of ODI. Results: In Group I, 79% of patients showed significant pain relief and functional improvement at 3 months, 6 months, and 12 months, a significant change from baseline. In Group II, 83%, 81%, and 79% of patients showed significant pain relief and functional improvement at 3 months, 6 months, and 12 months, a significant change from baseline. The majority of the patients experienced significant pain relief of 46 to 50 weeks, requiring approximately 3 to 4 treatments with an average relief of 16 weeks per episode of treatment. Conclusion: The majority of the patients in both groups experienced significant pain relief and improvement in functional status. Therapeutic thoracic medial branch blocks, with or without steroid, may provide a management option for chronic function-limiting mid back or upper back pain of facet joint origin. Key words: Chronic spinal pain, thoracic pain, thoracic facet or zygapophysial joint pain, facet joint nerve or medial branch blocks, comparative controlled local anesthetic blocks, therapeutic thoracic medial branch blocks

The Incidence of Intravascular Penetration in Medial Branch Blocks

Clinical observational study. To quantify the incidence of inadvertent intravascular injections in spinal medial branch blocks in a clinical setting. Previous research established the rate of inadvertent intravascular injection in lumbar medial branch blocks at 8%. The incidence of intravascular injection in cervical and thoracic medial branch blocks has not been reported previously. This study establishes the rate of inadvertent intravascular injection in patients receiving medial branch blocks of the cervical and thoracic spines. Further, this study reports a significantly lower rate of inadvertent intravascular injection for lumbar medial branch blocks than previously reported. Patients were originally referred to the clinic, for diagnosis and treatment of chronic spinal origin somatic pain. Medial branch blocks were then performed as diagnostic procedures to confirm the zygapophysial joint(s) as the suspected source of pain. Blocks were performed by experienced practitioners on nonidentified patients over a 3-year period. Clinical observations were recorded for 14,312 separate medial branch block levels. The level of the spine and the incidence of inadvertent intravascular injections were recorded. This study demonstrates that the overall incidence of intravascular penetration in medial branch blocks is rare, with an overall rate of 3.5%. This study also establishes the rate of intravascular injection for levels within the spine: the cervical spine is likely to be intravascular 3.9% of the time and the lumbar spine 3.7%, whereas the thoracic spine is significantly lower, with just 0.7% injections reported as intravascular. Significant differences were also observed between individual vertebral levels. The false-negative rate for medial branch blocks is likely to be lower than previously reported. The rate of inadvertent intravascular injection for thoracic medial branch blocks is 0.7%. Cervical and lumbar medial branch blocks are associated with an overall rate of 3.9% and 3.7%, respectively. Although these rates are lower than previously reported, the incidence of false-negative blocks still justifies the use of contrast to confirm nonvascular injection.

Evaluation of Therapeutic Thoracic Medial Branch Block Effectiveness in Chronic Thoracic Pain: A Prospective Outcome Study With Minimum 1-Year Follow Up

The prevalence of persistent upper back and mid back pain due to involvement of thoracic facet joints has been described in controlled studies as varying from 43% to 48% based on IASP criteria. Therapeutic intraventions utilized in managing chronic neck pain and low back pain of facet joint origin include intraarticular injections, medial branch nerve blocks, and neurolysis of medial branch nerves by means of radiofrequency. These interventions have not been evaluated in managing chronic thoracic pain of facet joint origin. To determine the clinical effectiveness of therapeutic thoracic medial branch blocks in managing chronic upper back and mid back pain of facet joint origin. A prospective outcome study. Interventional pain management setting in the United States. Fifty-five consecutive patients meeting the diagnostic criteria of thoracic facet joint pain by means of comparative, controlled diagnostic blocks were included in this evaluation. All medial branch blocks were performed in a sterile operating room under fluoroscopic visualization with mild sedation with midazolam and/or fentanyl. Statistical methods incorporated intent-to-treat analysis. Numeric pain scores, significant pain relief > or = 50%), Oswestry Disability Index, work status and Pain Patient Profile (P-3). Significant pain relief was defined as an average 50% or greater reduction of numeric pain rating scores. The results showed significant differences in numeric pain scores and significant pain relief (50% or greater) in 71% of the patients at three months and six months, 76% at 12 months, 71% at 24 months, and 69% at 36 months, compared to baseline measurements. Functional improvement was demonstrated at one year, two years, and three years from baseline. There was significant improvement with increase in employment among the patients eligible for employment (employed and unemployed) from baseline to one year, two years, and three years (61% vs 96% to 100%) and improved psychological functioning. Therapeutic thoracic medial branch blocks were an effective modality of treatment in managing chronic thoracic pain secondary to facet joint involvement confirmed by controlled, comparative local anesthetic blocks.

The surgical anatomy of thoracic facet denervation.

Thoracic percutaneous facet denervation has been employed for the treatment of thoracic zygapophysial joint pain. But the surgical anatomy of this procedure has been assumed to be the same as for lumbar medial branch neurotomy. To establish the anatomical basis for thoracic medial branch neurotomy, an anatomical study was undertaken. Using an X40 dissecting microscope, a total of 84 medial branches from 7 sides of 4 embalmed human adult cadavers were studied. The medial branches of the thoracic dorsal rami were found to assume a reasonably constant course. Upon leaving the intertransverse space, they typically crossed the superolateral corners of the transverse processes and then passed medially and inferiorly across the posterior surfaces of the transverse processes before ramifying into the multifidus muscles. Exceptions to this pattern occurred at mid-thoracic levels (T5-T8). Although the curved course remained essentially the same, the inflection occurred at a point superior to the superolateral corner of the transverse process. At no time during the dissection were nerves encountered crossing the junctions between the superior articular processes and transverse processes which have been the target points advocated for thoracic facet denervation. Rather, the results of this study indicate that the superolateral corners of the transverse processes are more accurate target points.