Humana Injections for Chronic Pain Conditions - Medicare Advantage Form

Please refer to CMS website for the most current applicable National Coverage Determination (NCD)/ Local Coverage Determination (LCD)/Local Coverage Article (LCA)/CMS Online Manual System/Transmittals. Injections for Chronic Pain Conditions Page: 2 of 34 Title ID Number Jurisdiction Medicare Administrative Contractors (MACs) Applicable States/Territories Type NCD LCD LCA Acupuncture for Chronic Lower Back Pain (cLBP) Epidural Steroid Injections for Pain Management Facet Joint Interventions for Pain Management Sacroiliac Joint Injections and Procedures Trigger Points, Local Injections Epidural Steroid Injections for Pain Management Facet Joint Interventions for Pain Management LCD LCA Peripheral Nerve Blocks Sacroiliac Joint Injections and Procedures Pain Management Epidural Steroid Injections for Pain Management LCD LCA Facet Joint Injections for pain Management Sacroiliac Joint Injections and Procedures LCD LCA Epidural Steroid Injections for Pain Management Facet Joint Injections for pain Management 30.3.3 L39054 A58777 L38841 A58477 L39475 A59257 L34588 A56909 L39036 A58745 L35936 A57826 L36850 A57452 L39455 A59233 L33622 A52863 L39015 A58731 L38773 A58364 L39383 A59154 L39240 A58993 L38801 A58403 L39462 J5, J8 - Wisconsin Physicians Service Insurance Corporation IA, KS, MO, NE IN, MI J6, JK - National Government Services, Inc. (Part A/B MAC) IL, MN, WI CT, NY, ME, MA, NH, RI, VT J15 - CGS Administrators, LLC (Part A/B MAC) KY, OH JE - Noridian Healthcare Solutions, LLC CA, HI, NV, American Samoa, Guam, Northern Mariana Islands Sacroiliac Joint Injections and Procedures Trigger Point Injections Epidural Steroid Injections for Pain Management Facet Joint Injections for Pain Management Sacroiliac Joint Injections and Procedures Trigger Point Injections Epidural Steroid Injections for Pain Management LCD LCA LCD LCA Facet Joint Injections for Pain Management LCD LCA Trigger Point Injections Epidural Steroid Injections for Pain Management Facet Joint Injections for Pain Management Sacroiliac Joint Injections and Procedures Trigger Point Injections Epidural Steroid Injections for Pain Management Facet Joint Injections for Pain Management LCD LCA Peripheral Nerve Blocks Injection of Trigger Points A59244 L34211 A57701 L39242 A58995 L38803 A58405 L39464 A59246 L36859 A57702 L36920 A56681 L34892 A56670 L35010 A57751 L38994 A58695 L38765 A58350 L39402 A59192 L37635 A56745 L33906 A56651 L33930 A57787 L33933 A57788 L33912 A57114 Injections for Chronic Pain Conditions Page: 3 of 34 JF - Noridian Healthcare Solutions, LLC AK, AZ, ID, MT, ND, OR, SD, UT, WA, WY JH, JL - Novitas Solutions, Inc. (Part A/B MAC) AR, CO, NM, OK, TX, LA, MS DE, DC, MD, NJ, PA JJ, JM - Palmetto GBA (Part A/B MAC) AL, GA, TN NC, SC, VA, WV JN - First Coast Service Options, Inc. (Part A/B MAC) FL, PR, US VI Injections for Chronic Pain Conditions Page: 4 of 34 Description Injections for chronic pain conditions may be given for either diagnostic or therapeutic (treatment) purposes and may include epidural steroid injections, facet joint injections, regional sympathetic nerve blocks, sacroiliac joint injections, trigger point injections, dry needling of trigger points and/or peripheral nerve blocks. These injections are often included as part of a pain management program. Epidural Steroid Injections An epidural steroid injection (ESI) is used to help reduce radicular spinal pain that may be caused by pressure on a spinal nerve root as a result of a herniated disc, degenerative disc disease or spinal stenosis. This treatment is most frequently used for low back pain, though it may also be used for cervical (neck) or thoracic (midback) pain. An anesthetic medication, with or without a steroid (eg, corticosteroid, dexamethasone), is injected into the epidural space near the affected spinal nerve root with the assistance of computed tomography (CT) or fluoroscopy which allows the physician to view the placement of the needle. The goal of this treatment is to reduce inflammation and block the spinal nerve roots to relieve radicular pain or sciatica. It can also provide sufficient pain relief to allow the individual to progress with their rehabilitation program. Approaches to the epidural space for the injection include: • Caudal – The needle is placed near the coccyx (tailbone) into the sacral hiatus, allowing the treatment of pain which radiates into the lower extremities. This approach is commonly used to treat lumbar radiculopathy after prior surgery in the low back (post-laminectomy pain syndrome). • Interlaminar – The needle is placed between the lamina of two vertebrae directly from the middle of the back. Medication is delivered to the nerve roots, via the epidural space, on both the right and left sides of the inflamed area at the same time. • Selective nerve root block (SNRB) – The needle targets a specific nerve root, rather than the epidural space, delivering an anesthetic along the nerve itself. These injections generally should only be used for diagnostic purposes, often as part of surgical planning. While SNRBs are technically not an ESI, they are frequently discussed with them, and the terms may also erroneously be used interchangeably. They may also be referred to as diagnostic selective nerve root blocks (DSNRBs). • Transforaminal – The needle is placed under radiographic guidance in such a way as to allow the medication to be directly applied onto the affected spinal nerve via the intervertebral foramen that lodges the nerve. This method treats one side at a time but, depending on the volume of the medication used, it may spread to one or multiple levels; it has been proposed to inject one or multiple levels during the same session, and either one or both sides. Facet Joint Injections Facet injections, also known as facet blocks or medial branch blocks, are injections of a local anesthetic, with or without a steroid medication, into the facet joints or their nerve supply, the medial branch nerve. Injections for Chronic Pain Conditions Page: 5 of 34 Facet injections may be given for diagnostic purposes to determine if the facet joint is the source of pain16 and must be performed under CT- or fluoroscopy-guidance. If the pain is relieved, the physician will know that the facet joint is likely to be the source of pain. A therapeutic facet block or a facet denervation may follow a successful diagnostic facet block. Regional Sympathetic Nerve Blocks Regional sympathetic nerve blocks are performed by injecting a local anesthetic into the region of the relevant sympathetic ganglia, for the treatment of complex regional pain syndrome ([CRPS], previously known as reflex sympathetic dystrophy [RSD]). At the cervical level, these blocks may be referred to as stellate ganglion blocks and in the thoracic or lumbar level as paravertebral sympathetic blocks. As with other blocks, these may both aid in diagnosis of CRPS and be given as a therapeutic injection. Sacroiliac Joint Injections Sacroiliac (SI) joint injections are performed by injecting a local anesthetic, with or without a steroid medication, into the SI joints. These injections may be given for diagnostic purposes to determine if the SI joint is the source of the low back pain or may be performed to treat SI joint pain that has previously been diagnosed. If the pain is relieved, the physician will know that the SI joint appears to be the source of pain. This may be followed up with therapeutic injections of anti-inflammatory (steroid) and/or local anesthetic medications to relieve pain for longer periods. Trigger Point Injections Trigger point injections (TPI) are injections of a local anesthetic, with or without a steroid medication, into a painful area of a muscle that contains the trigger point. The purpose of a TPI is to relax the area of intense muscle spasm, effectively inactivate the trigger point and provide prompt symptomatic pain relief. Dry Needling of Trigger Points Dry needling differs from traditional acupuncture, even though it does make use of acupuncture-type needles. Acupuncture follows the principles of energy flow as a guide to where the needles will be inserted; in dry needling, needles are inserted directly into a myofascial trigger point, in an attempt to inactivate it, thereby theoretically decreasing the associated pain. Dry needling, even though it targets a trigger point, does differ from a trigger point injection, as there is no injection of medication or fluid. Peripheral Nerve Block Peripheral nerve blocks consist of injection of a local anesthetic, with or without a steroid, into a peripheral nerve or a nerve ganglion, in an attempt to block pain signals and in theory provide prolonged relief from pain. Examples of peripheral nerve blocks include, but may not be limited to, cluneal nerve block, coccygeal nerve block, ganglion impar block, genicular nerve block, obturator nerve block or splanchnic nerve block. Other Therapeutic Injections Injections may also be given into other structures in an attempt to alleviate chronic pain. Examples include, but may not be limited to, iliotibial (IT) band injection, intradiscal injection, pedicle screw block/hardware block of instrumentation used in spinal fusion or sacrococcygeal junction/sacrococcygeal ligament injection. Injections for Chronic Pain Conditions Page: 6 of 34 Coverage Determination Humana follows the CMS requirement that only allows coverage and payment for services that are reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member except as specifically allowed by Medicare. In interpreting or supplementing the criteria above and in order to determine medical necessity consistently, Humana may consider the following criteria. NOTE: The scope of this policy is limited to CHRONIC pain management; it is NOT intended for use in consideration of acute postoperative pain control. Epidural Steroid Injections Please refer to the above CMS guidance for information regarding epidural steroid injections. Facet Joint Injections/Medial Branch Nerve Blocks Please refer to the above CMS guidance for information regarding facet joint injections/medial branch nerve blocks. Regional Sympathetic Nerve Blocks Regional sympathetic nerve blocks will be considered medically reasonable and necessary when the following requirements are met: • Diagnosis when sympathetically mediated CRPS is suspected as evidenced by ALL of the following criteria being met: o Continued, ongoing pain, disproportionate to any inciting event (eg, surgery, trauma); AND o ONE or more symptoms from EACH of the following categories:  Sensory: hyperesthesia, allodynia  Vasomotor: temperature asymmetry, skin color changes, skin color asymmetry  Sudomotor/edema: edema, sweating changes, sweating asymmetry  Motor/trophic: decreased range of motion (ROM), motor dysfunction (weakness, tremor, dystonia), trophic changes (hair, nails, skin); AND o ONE or more findings on physical exam in TWO or more of the following categories:  Sensory: evidence of: hyperalgesia (to pinprick), allodynia (to light touch) Injections for Chronic Pain Conditions Page: 7 of 34  Vasomotor: evidence of: temperature asymmetry, skin color changes, skin color asymmetry  Sudomotor/edema: evidence of: edema, sweating changes, sweating asymmetry  Motor/trophic: evidence of: decreased ROM, motor dysfunction (weakness, tremor, dystonia), trophic changes (hair, nails, skin); AND • Failure to improve after 12 weeks of conservative treatment under the direction of a healthcare professional, including ALL of the following: o Activity/lifestyle modification; AND o Medications (eg, nonsteroidal anti-inflammatory drugs [NSAIDs], non-narcotic analgesics) if medically appropriate and not contraindicated; AND o Physical therapy (PT), including a home exercise program (HEP); AND • Real-time imaging guidance (CT scan or fluoroscopy) must be used to assure proper needle placement for either diagnostic or therapeutic injections (this is considered integral to the primary procedure and not separately reimbursable55); AND • Utilization of these blocks is to be with the intent to allow participation in an active rehabilitation program Diagnostic Phase: • A diagnostic block is performed to confirm (or disprove) the presence of sympathetically mediated CRPS; AND • A second diagnostic block may be performed if the initial block was successful (a 50% reduction in pain and improved function) and if performed within the first 2 weeks of the initial block; AND • If the diagnostic phase is completed and unsuccessful (less than 50% pain relief and no improvement in function), no further injections will be covered Therapeutic Phase: • If the diagnostic phase is completed and successful (at least a 50% reduction in pain and improvement in function), therapeutic injections may be initiated; AND • Up to a maximum of 6 total blocks may be performed at a frequency of no more than one per week (per rolling 12 month period*): AND all of the following: o A 50% reduction in pain is achieved; AND Injections for Chronic Pain Conditions Page: 8 of 34 o Decrease in pain medication use; AND o Improved/increased functional ability (increased ROM, strength and use of the extremity in activities of daily living [ADLs], increased tolerance to touch); AND o Ongoing participation in an active rehabilitation program *A rolling 12 month period is 12 months after an event, regardless of what month the initial event took place (eg, first diagnostic injection is given August 1, 2023, the rolling 12 month period would end July 31, 2024). Limitations: Regional sympathetic nerve blocks will not be considered medically reasonable and necessary for any indications other than those listed above including, but may not be limited to: • Diagnostic block was not successful (less than 50% reduction in pain); OR • Individual is not capable of or willing to participate in an ongoing, active rehabilitation program; OR • Regional sympathetic nerve blocks performed without imaging guidance; OR • Repeat therapeutic block when there has not been any decrease in pain medication use, increased function/participation in ADLs or increased tolerance to touch; OR • When other types of injections are performed on the same date of service including, but not limited to, epidural steroid injections, facet joint blocks/medial branch nerve blocks, sacroiliac joint injections and/or trigger point injections. (Multiple injections on the same day could lead to an inaccurate or lack of diagnosis) Ultrasound guidance for needle placement will not be considered medically reasonable and necessary for performing regional sympathetic nerve blocks.32-39 Monitored anesthesia care (MAC), moderate or deep sedation or general anesthesia for regional sympathetic nerve blocks will not be considered medically reasonable and necessary. Even in an individual with a needle phobia and anxiety, typically oral anxiolytics suffice.24-39,44-49 Sacroiliac Joint Injections Intra-articular sacroiliac joint injections will be considered medically reasonable and necessary when the following requirements are met: • Chronic moderate to severe low back pain (pain below L5 without radiculopathy and over the anatomical location of the SIJ) when the sacroiliac joint is suspected to be the source of pain; AND Injections for Chronic Pain Conditions Page: 9 of 34 • Pain duration of at least 3 months; AND • Failure to improve or inability to tolerate noninvasive care despite a minimum of 4 weeks of conservative therapies (may include, but not be limited to, medications [eg, nonsteroidal anti-inflammatory drugs (NSAIDs), non-narcotic analgesics] if medically appropriate and not contraindicated, physical therapy, etc.); AND • The SIJ procedure(s) should be performed in conjunction with conservative treatments; AND • Individual should be a part of an ongoing, and be actively participating in, a rehabilitation program, HEP or functional restoration program; AND • Positive response (reproduction of individual’s typical SIJ pain) to at least 3 of the following provocative tests/maneuvers: o Compression test o Distraction test o FABER test (also referred to as Patrick test) o Gaenslen’s test o Thigh thrust test (also referred to as posterior pelvic pain provocation o Yeoman test; AND • Sacroiliac joint injections are to be performed with imaging guidance (CT scan or fluoroscopy) to assure correct needle placement (this is considered integral to the primary procedure and not separately reimbursable55), except ultrasound guidance may be considered reasonable and necessary when there is a documented contrast allergy or pregnancy44-49 Diagnostic Phase: • During the diagnostic phase, an individual may receive 2 injections at intervals of no sooner than 2 weeks; AND • If injections are to be done for different joints (left versus right) they are to be done at intervals of no sooner than one week apart (though it is recommended that both joints be injected at the same time); AND • If the diagnostic phase is completed and unsuccessful (less than an 75% reduction in pain and/or symptoms), no further injections will be covered Therapeutic Phase: • Subsequent therapeutic SIJ injections are considered medically reasonable and necessary when the subsequent SIJ injections are provided at the same anatomic site as therapeutic SIJ injection; AND • The therapeutic SIJ injection produced at least consistent 50% pain relief or at least 50% consistent improvement in the ability to perform previously painful movements and activities of daily living (ADLs) Injections for Chronic Pain Conditions Page: 10 of 34 for at least 3 months from the proximate therapeutic SIJ injection procedure and compared to baseline measurements for ADLS and painful movements or pain relief using the same pain scale** AND • No more than 4 therapeutic SIJ injection sessions, unilateral or bilateral, will be reimbursed per rolling 12 months*. To clarify, a therapeutic SIJ injection session if performed on one side first and then on the opposite side at a different session would qualify as 2 sessions for the limitation of 4 therapeutic SIJ sessions per rolling 12 months* **The scales used to measure of pain and/or disability must be documented in the medical record. Acceptable scales include but are not limited to: verbal rating scales, Numerical Rating Scale (NRS) and Visual Analog Scale (VAS) for pain assessment, and Pain Disability Assessment Scale (PDAS), Oswestry Disability Index (ODI), Oswestry Low Back Pain Disability Questionnaire (OSW), Quebec Back Pain Disability Scale (QUE), Roland Morris Pain Scale, Back Pain Functional Scale (BPFS), and the PROMIS profile domains to assess function. Limitations: Sacroiliac joint injections will not be considered medically reasonable and necessary for the following indications: • Lateral branch nerve blocks to the SI joint for diagnostic or therapeutic purposes OR for diagnostic purposes prior to a neuroablative procedure to the SI joint.; OR • Repeat SI joint injections when significant improvement has occurred after the initial injection or any subsequent injections. Repeat injections should only be performed upon return of pain and deterioration in the functional status; OR • SI joint injections performed without imaging guidance44-49; OR • When other types of injections are performed on the same date of service including, but not limited to, epidural steroid injections, facet injections, sympathetic blocks and/or trigger point injections. (Multiple injections on the same day could lead to an inaccurate or lack of diagnosis)44-49 Monitored anesthesia care (MAC), moderate or deep sedation or general anesthesia for SIJ injections will not be considered medically reasonable and necessary. Even in an individual with a needle phobia and anxiety, typically oral anxiolytics suffice.44-49 Trigger Point Injections Trigger point injections will be considered medically reasonable and necessary for the treatment of myofascial pain syndrome when the following requirements are met: • Failure to improve or inability to tolerate noninvasive conservative care (may include, but not be limited to, medications [eg, NSAIDs, muscle relaxants, etc.] if medically appropriate and not contraindicated, PT, activity modification, home exercise instruction, etc.); AND Injections for Chronic Pain Conditions Page: 11 of 34 • Documentation in the medical record should reflect all treatment methods attempted and the results; if treatments are contraindicated, the medical record should indicate why the trigger point(s) is not amenable to other therapeutic modalities; AND • Repeat trigger point injections may be necessary when there is evidence of persistent pain or inflammation. Evidence of partial improvements to the range of motion in any muscle area after an injection would justify a repeat injection; AND • In addition, several studies indicated that when additional injections are required in a series, other therapies (eg, medications, PT) in addition to the injections may be beneficial Limitations: Trigger point injections will not be considered medically reasonable and necessary for the following: • The frequency at which trigger point injection(s) are performed is dependent on the clinical presentation of the individual. However, it is generally expected that the individual’s response to the previous injection is important in deciding whether to proceed with additional injections. If the individual has achieved significant benefit after the first injection, an additional injection would be appropriate for reoccurring symptoms. (Repeated injections may be justified by evidence of improvement, such as reduction in pain, muscle tenderness, spasm; or improvement in the range of motion)40; • Multiple trigger points may be injected during any one session. Some trigger points may need to be re- injected weekly or monthly for brief intervals consisting of a few months, depending on the results of the injections and the relief of pain that the injection provides40; • If therapeutic effect is achieved, medical literature supports that no more than 3 sets (or sessions) of injections should be performed during 1 year40; • If the individual experiences no symptom relief or functional improvement after 2 to 3 injections into a muscle, repeated injections into that muscle are not recommended40; • It is not recommended that trigger point injections be used on a routine basis for patients with chronic non-malignant pain syndromes40; • Prolotherapy, the injection into a damaged tissue of an irritant to induce inflammation, is not covered by Medicare. Billing this under the trigger point injection codes is misrepresentation50-53 Monitored anesthesia care (MAC), moderate or deep sedation or general anesthesia for trigger point injections will not be considered medically reasonable and necessary. Even in an individual with a needle phobia and anxiety, typically oral anxiolytics suffice.24-39,44-49 The use of the criteria in this Medicare Advantage Medical Coverage Policy provides clinical benefits highly likely to outweigh any clinical harms. Services that do not meet the criteria above are not medically Injections for Chronic Pain Conditions Page: 12 of 34 necessary and thus do not provide a clinical benefit. Medically unnecessary services carry risks of adverse outcomes and may interfere with the pursuit of other treatments which have demonstrated efficacy. In interpreting or supplementing the criteria above and in order to determine medical necessity consistently, Humana may consider MCG Guidelines. Coverage Limitations US Government Publishing Office. Electronic code of federal regulations: part 411 – 42 CFR § 411.15 - Particular services excluded from coverage Dry Needling Dry needling (needle insertion without injection) will not be considered medically reasonable and necessary for any indications other than chronic low back pain including, but may not be limited to, trigger points.50, 52 A review of the current medical literature shows that the evidence is insufficient to determine that this service is standard medical treatment. There remains an absence of randomized, blinded clinical studies examining benefit and long-term clinical outcomes establishing the value of this service in clinical management. Other Miscellaneous Injections for Pain Conditions The following injections will not be considered medically reasonable and necessary for any indication, including for management/treatment of chronic pain: • Coccygeal nerve block; OR • Iliotibial (IT) band injection; OR • Intradiscal injection with ANY substance (eg, allogenic cellular product, allogenic tissue-based product, mesenchymal stem cells, methylene blue, notochordal cell-derived matrix, oxygen/ozone, platelet rich plasma [PRP], steroids, tumor necrosis factor [TNF] alpha, VIA disc allograft [may also be referred to as VIA disc matrix]); OR • Obturator nerve block; OR • Paravertebral block for chronic pain (paravertebral blocks may be appropriate when used for immediate postoperative pain management, for specific surgical procedures, however, this indication is outside of the scope of this Medical Coverage Policy) A review of the current medical literature shows that the evidence is insufficient to determine that this service is standard medical treatment. There remains an absence of randomized, blinded clinical studies examining benefit and long-term clinical outcomes establishing the value of this service in clinical management. Injections for Chronic Pain Conditions Page: 13 of 34 The following injections will not be considered medically reasonable and necessary for any indication, including for management/treatment of chronic pain: • Pedicle screw block/hardware block of instrumentation used in spinal fusions; OR • Repetitive peripheral nerve blocks for chronic nonmalignant pain; OR • Sacrococcygeal junction/sacrococcygeal ligament injection (for any indication, including coccydynia); OR • Splanchnic nerve block A review of the current medical literature shows that there is no evidence to determine that these services are standard medical treatments. There is an absence of randomized, blinded clinical studies examining benefit and long-term clinical outcomes establishing the value of these services in clinical management. Monitored anesthesia care (MAC), moderate or deep sedation or general anesthesia for coccygeal, obturator or splanchnic nerve blocks, IT band, intradiscal or sacrococcygeal junction/ligament injections or paravertebral or pedicle screw/hardware blocks will not be considered medically reasonable and necessary. Even in an individual with a needle phobia and anxiety, typically oral anxiolytics suffice.24-39,44-49 Summary of Evidence Coccygeal Nerve Block UpToDate gave a weak recommendation with low quality evidence for use of coccygeal injections containing local anesthetic or local anesthetic plus glucocorticoid in patients with persistent coccydynia of greater than 2 months.148 Iliotibial (IT) Band Injection There is a small quantity of high-quality evidence available regarding treatment of iliotibial band syndrome (ITBS). A limitation in treating ITBS is uncertainty regarding where the pain originates from and whether the cause is due to a tendon injury or inflammation. The recommended treatment from UpToDate is based mostly from case series, expert opinions, and clinical experience. They recommend glucocorticoid injections for patients with persistent significant pain despite being compliant with 6 to 12 weeks of acute and subacute treatment. There is limited evidence that suggest that glucocorticoid injections provide short- term relief of pain caused by ITBS, however long-term benefits are questionable.151 Intradiscal Injection UpToDate does not recommend intradiscal injection of glucocorticoid, anti-tumor necrosis factor (TNF) or methylene blue for chronic low back pain. One study that found that intradiscal glucocorticoid injections may provide short-term pain relief in patients with chronic low back pain associated with radiologic evidence of active discopathy, but this clinical scenario is a small percentage of subacute or chronic low back pain. Another prospective, double-blind, randomized controlled trial with 135 patients found that a single intradiscal injection of prednisone and contrast resulted in higher rates of response at one month compared with an injection of only contrast. At 12 months, the groups did not differ in pain intensity or any Injections for Chronic Pain Conditions Page: 14 of 34 other secondary outcomes including activity limitations, quality of life, anxiety and depression, employment status and use of analgesics at 1 or 12 months. Additional research is needed to assess efficacy and safety and to demonstrate reproducible beneficial effects of intradiscal glucocorticoid injection. A small pilot study concluded that intradiscal injections of etanercept which interferes with TNF-alpha did not improve pain or disability scores for patients with lumbosacral radiculopathy or chronic discogenic low back pain. Methylene blue is a compound used as a dye or stain and has been studied for various therapeutic purposes. The results of trials evaluating intradiscal methylene blue injections are varied. One randomized trial with 72 patients with discogenic back pain showed a large improvement in pain and function with intradiscal methylene blue injection compared with a placebo intradiscal injection. However, in another randomized trial with 81 patents and similar inclusion criteria there were no differences between the intradiscal methylene blue versus placebo in pain intensity, likelihood of >30 percent improvement in pain, function, quality of life, or function through 6 months. Similarly, in another small, randomized trial including 24 patients, there was no difference between intradiscal methylene blue versus placebo intradiscal injection in pain or function after one month, and over half of the patients treated with methylene blue reported severe pain immediately after the injection.160 AHRQ completed a comparative effectiveness review on interventional treatments for acute and chronic pain. Intradiscal methylene blue for low back pain of presumed discogenic was evaluated in two trials that compared methylene blue versus sham intradiscal therapy. It was found in one trial that intradiscal methylene blue for presumed discogenic back pain was associated with no difference versus shame at 6 weeks and 3 months. In both trials, the evidence was insufficient to determine effects of intradiscal methylene blue at 6 months. In one of the trials, the evidence was insufficient to determine the effects at 12 months or longer.2 Intradiscal ozone injection for radicular low back pain or nonradicular low back pain of presumed discogenic origin was also evaluated by the AHRQ using 3 trials with follow up at 6 months. It was found that evidence was insufficient to assess intradiscal oxygen-ozone for radicular low back pain in one trial with 159 patients. None of the trials evaluated intradiscal oxygen-ozone injection without corticosteroid or oxygen-ozone injection for presumed nonradicular discogenic low back pain. All 3 trials compared oxygen-ozone plus corticoid versus corticosteroid without oxygen-ozone. One trial additionally evaluated a local anesthetic without corticosteroid control injection. There was fair quality in one of the trials while the other 2 had poor quality. Limitations noted in all trials included unclear randomization and allocation methods.2 Lewandrowski et al, assessed the efficacy and safety of allogenic mesenchymal stem cell (MSC) injection into painful lumbar intervertebral discs and associated clinical outcomes in a retrospective, observational cohort study. No patient required additional treatments for low back pain stemming from the level treated with MSC injections. The study was limited by patient selection, hindsight bias and low patient numbers with 33 patients. It was concluded that the study suggested that the injection of allogeneic MSCs to treat patients with painful intermediate-stage degenerative disc disease has value, but they recommend additional randomized prospective studies to validate this research.109 The American Society of Interventional Pain Physicians (ASIPP) graded the evidence as a level III for intradiscal injections of platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs). Level III evidence is defined as fair with evidence obtained from at least one relevant high quality nonrandomized trial or observational study with multiple moderate or low-quality observational studies.15 Injections for Chronic Pain Conditions Page: 15 of 34 Obturator Nerve Block Hayes reported that there currently is not enough published peer-reviewed literature to evaluate the evidence related to nerve blockade of the articular branches of the femoral and obturator nerves for treatment of hip arthritis in a full assessment.76 Paravertebral Block for Chronic Pain Hayes gave a C rating which they define as a potential but unproven benefit for paravertebral blocks (PVBs) administered in perioperative period for prevention of chronic pain in patients with American Society of Anesthesiology physical status classification I to III who undergo surgery for breast cancer. This rating was given due to the low-quality body of evidence. A D2 rating, defined as insufficient evidence, was given for PVBs administered in the perioperative period for prevention of chronic pain in patients who undergo breast surgery for noncancer-related indications. This rating was due to the insufficient evidence available for this indication.93