Minimally invasive lumbar decompression: a review of indications, techniques, efficacy and safety

Pacific Spine and Pain Society (PSPS) Evidence Review of Surgical Treatments for Lumbar Degenerative Spinal Disease: A Narrative Review

INTRODUCTION

Interventional treatment options for the lumbar degenerative spine have undergone a significant amount of innovation over the last decade. As new technologies emerge, along with the surgical specialty expansion, there is no manuscript that utilizes a review of surgical treatments with evidence rankings from multiple specialties, namely, the interventional pain and spine communities. Through the Pacific Spine and Pain Society (PSPS), the purpose of this manuscript is to provide a balanced evidence review of available surgical treatments.

METHODS

The PSPS Research Committee created a working group that performed a comprehensive literature search on available surgical technologies for the treatment of the degenerative spine, utilizing the ranking assessment based on USPSTF (United States Preventative Services Taskforce) and NASS (North American Spine Society) criteria.

RESULTS

The surgical treatments were separated based on disease process, including treatments for degenerative disc disease, spondylolisthesis, and spinal stenosis.

CONCLUSIONS

There is emerging and significant evidence to support multiple approaches to treat the symptomatic lumbar degenerative spine. As new technologies become available, training, education, credentialing, and peer review are essential for optimizing patient safety and successful outcomes.

Predictors of Admission to Post-Acute Rehabilitation Following Multi-Level Spinal Decompression and Fusion Surgery and Its Associated Outcomes

OBJECTIVE

To investigate predictive factors and outcomes in those admitted to post-acute rehabilitation (PAR) versus those that discharged home following multi-level spinal decompression and fusion surgery.

METHODS

Retrospective case review study of adults that underwent multi-level spinal decompression and fusion surgery between 2016 and 2022 at an academic institution. Preoperative, perioperative, postoperative, and outcomes variables were compared between those discharged home versus PAR. Finally, multiple logistic regression was used to determine factors contributing to PAR admission.

RESULTS

Of 241 total patients, 89 (37%) discharged home and 152 (63%) discharged to PAR. Among home discharge patients, 45.9% used an assistive device, while among PAR patients, 61.5% used 1 (P = 0.041). Mean pre-operative Oswestry Disability Index score was significantly lower in the home discharge group compared to the PAR discharge group (40.3 vs. 45.3 respectively, P = 0.044). Females were 2.43 times more likely to be discharged to PAR compared to males (95% CI: 1.06, 5.54, P = 0.04). Patients with a mood disorder had 2.81 times higher odds of being discharged to PAR compared to those without (95% CI: 1.20, 6.60, P = 0.02). Other variables evaluated were not statistically significant.

CONCLUSIONS

Female sex and presence of a mood disorder increase the likelihood to PAR discharge following multi-level spinal decompression surgery.

Impact of American Society of Anesthesiologists' Classification on Postoperative Satisfaction and Clinical Outcomes Following Lumbar Decompression: Cohort-Matched Analysis

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim was to compare patient-reported outcomes (PROMs), minimum clinically important difference (MCID) achievement, and postoperative satisfaction following minimally invasive lumbar decompression in patients stratified by American Society of Anesthesiologists (ASA) classification.

SUMMARY OF BACKGROUND DATA

Some guidelines recommend against performing elective procedures for patients with an ASA score of 3 or greater; however, long-term postoperative outcomes are not well described.

METHODS

Primary, single-level, minimally invasive lumbar decompression procedures were identified. PROMs were administered at preoperative, 6-week, 12-week, 6-month, 1-year, 2-year timepoints and included Patient-Reported Outcomes Measurement Information System-Physical Function, visual analog scale (VAS) back/leg, Oswestry disability index (ODI), and 12-item short form physical component score. Satisfaction scores were collected postoperatively for VAS back/leg, ODI, and individual ODI subcategories. Patients were grouped (ASA<3, ASA≥3), and propensity scores were matched to control for significant differences. Demographic and perioperative characteristics were compared using χ 2 and the Student's t test. Mean PROMs and postoperative satisfaction were compared at each time point by a 2-sample t test. Postoperative PROM improvement from the preoperative baseline within each cohort was calculated with a paired t test. MCID achievement was determined by comparing ΔPROMs to established thresholds and comparing between groups using simple logistic regression.

RESULTS

One hundred and twenty-nine propensity-matched patients were included: 99 ASA<3 and 30 ASA≥3. No significant demographic differences were observed between groups. ASA≥3 patients experienced significantly increased length of stay and postoperative narcotic consumption on surgery day ( P <0.048, all). Mean PROMs and MCID achievement did not differ. The ASA<3 cohort significantly improved from the preoperative baseline for all PROMs at all postoperative time points. ASA<3 patients demonstrated higher levels of postoperative satisfaction at 6 weeks for VAS leg, VAS back, ODI, sleeping, lifting, walking, standing, sex, travel, and at 6 months for VAS back ( P <0.045, all).

CONCLUSION

ASA≥3 patients may achieve similar long-term clinical outcomes to ASA<3 patients, though they may show poorer short-term satisfaction for disability, leg pain, and back pain, which could be related to differing preoperative expectations.

The MOTION study: Two-year results of a real-world randomized controlled trial of the mild® procedure for treatment of lumbar spinal stenosis

OBJECTIVE

The MOTION study is designed to measure the impact of percutaneous image-guided lumbar decompression as a first-line therapy on patients otherwise receiving real-world conventional medical management for lumbar spinal stenosis with neurogenic claudication secondary to hypertrophic ligamentum flavum. This prospective, multicenter randomized controlled trial uses objective and patient-reported outcome measures to compare the combination of the mild® percutaneous treatment and nonsurgical conventional medical management (CMM) to CMM-Alone.

METHODS

Test group patients received the mild procedure after study enrollment. Test and control groups were allowed conventional conservative therapies and low-risk interventional therapies as recommended by their physicians. Subjective outcomes included the Oswestry Disability Index, Numeric Pain Rating Scale, and Zurich Claudication Questionnaire. Objective outcomes included a validated Walking Tolerance Test, the rate of subsequent lumbar spine interventions, and safety data.

RESULTS

Two-year follow-up included 64 mild + CMM and 67 CMM-Alone patients. All outcome measures showed significant improvement from baseline for mild + CMM, whereas the majority of CMM-Alone patients had elected to receive mild treatment or other lumbar spine interventions by 2 years, precluding valid 2-year between-group comparisons. Neither group reported any device- or procedure-related adverse events.

CONCLUSIONS

The durability of mild + CMM for this patient population was demonstrated for all efficacy outcomes through 2 years. Improvements in walking time from baseline to 2 years for patients treated with mild + CMM were significant and substantial. The lack of reported device or procedure-related adverse events reinforces the strong safety profile of the mild procedure. These results provide support for early interventional treatment of symptomatic LSS with the mild procedure.

Quantum Molecular Resonance Radiofrequency Disc Decompression and Percutaneous Microdiscectomy for Lumbar Radiculopathy

Within the practice of pain management, one of the most commonly encountered events is low back pain. Lumbar radiculopathy (LR) is a pain syndrome caused by the compression or irritation of the nerve roots in the lower back due to lumbar disc herniation, vertebra degeneration, or foramen narrowing. Symptoms of LR include low back pain that propagates toward the legs, numbness, weakness, and loss of reflexes. The aim of this study is to assess the long-term effectiveness of quantum molecular resonance disc decompression and its combination with a percutaneous microdiscectomy using Grasper© forceps (QMRG) in patients with persistent lumbar radiculopathy (LR) in relation to patient physical stress status. The main outcome measures of this prospective observational study were DN4, NRS, ODI, SF12, PGI, CGI, and MOS Sleep Scale. An improvement 12 months post-intervention was observed in patients without physical stress, presenting better overall results. The mean change was over the minimal clinically important difference in 64.3% of outcome measures studied for the whole sample. QMRG appears to be an effective treatment option for LR, but a reduction in physical stress is needed to ensure long-term effectiveness.

Lumbar Epidural Hematoma as a Rare Complication From Minimally Invasive Lumbar Decompression

Lumbar spinal stenosis (LSS) is a common and debilitating pathology globally. Conservative and surgical treatment options exist for patients. Recently, minimally invasive lumbar decompression (MILD) has been described as a less invasive technique for the treatment of early spinal stenosis ≥2.5mm ligamentum thickening or in patients at high risk for general anesthesia. Often, MILD is performed by interventional pain providers and shows low complication rates. We describe a 76-year-old woman who presented to the emergency department immediately after undergoing a MILD procedure at an outside surgery center with lower back/sacral pain resulting from an acute epidural hematoma extending from T12-L3. Early recognition and surgical evacuation resulted in a good outcome with no complications. Our goal is to increase awareness of this rare complication and encourage multidisciplinary approaches to managing LSS between spine surgeons and pain providers.

Lumbar Spinal Stenosis and Minimally Invasive Lumbar Decompression: A Narrative Review

Background

Lumbar spinal stenosis (LSS) is a common pain condition that causes lumbar back pain, radiating leg pain, and possible functional impairment. MILD is an emerging minimally invasive treatment for LSS. It is an image-guided percutaneous procedure designed to debulk hypertrophied ligamentum flavum. However, the exact short- and long-term efficacy, safety profile, indication criteria, and certain procedure details reported in medical literature vary.

Objective

This narrative review was to elucidate efficacy, safety profile, certain procedure details, advantages, and limitations of MILD.

Study Design

This is a narrative review.

Setting

All included articles are clinic trials including analytic studies and descriptive studies.

Methods

PubMed, Cochrane Library, and Scopus were searched. Only clinical trials of MILD procedure were included. Information of indications, contraindications, VAS scores, ODI scores, effective rate, efficacy durations, and certain procedure details was focused on.

Results

According to the literature, for the MILD procedure, the VAS score could be reduced from a pre-treatment level of 6.3-9.6 to a post-treatment level of 2.3-5.8. The ODI score could be reduced from a pre-treatment level of 38.8-55.3 to a post-treatment level of 27.4-39.8. The effective rate of the MILD procedure was reported to be 57.1%-88%. A 2-year postoperative stability of efficacy was also supported. One RCT study testified superior efficacy of MILD over epidural steroid injection.

Limitations

There is few high-quality literature in the review. Moreover, the long-term efficacy of MILD cannot be revealed according to the current literature.

Conclusion

Based on the reviewed literature, MILD is an effective and safe procedure. MILD can reduce pain intensity and improve functional status significantly. Therefore, it is a preferable option for LSS patients who failed conservative treatments, but not for those who require immediate invasive decompression surgery.

Pain Management Interventions in Lumbar Spinal Stenosis: A Literature Review

Lumbar spinal stenosis (LSS) occurs due to the narrowing of the space within the vertebral canal and or intervertebral foramina. This results in the compression of the spinal cord and possibly the roots of the spinal nerves. Lower back pain and neurogenic claudication (NC) are major symptoms of spinal stenosis. This is a literature review that summarizes the important findings pertaining to pain management of spinal stenosis. Twenty-four original articles were assessed. Pain can be treated through non-invasive or surgical methods. Conservative techniques include physical exercises, epidural corticosteroid injection, local anesthetic injection therapy, and oral analgesics. Surgical intervention deals with the decompression of the affected spinal region, with or without vertebral fusion surgery. Other novel surgical techniques include implantation of specific equipment, known as interspinous spacer devices and minimally invasive lumbar decompression (MILD). Most studies offering a comparative analysis have demonstrated that surgical intervention is more efficacious than non-surgical interventions to manage pain associated with spinal stenosis.

Nonsurgical Interventional Spine Pain Procedures: Outcomes and Complications

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Nonsurgical interventional spine pain procedures provide an additional treatment option for lower back pain at the traditional bifurcation of conversative vs. operative management.

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Transforaminal epidural steroid injections, radiofrequency ablations, intrathecal drug delivery, and spinal cord stimulation were found to be effective and safe techniques when applied to their specific indication.

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Thermal annuloplasty and minimally invasive lumbar decompression showed mixed support.

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Discography, sacroiliac joint injections, and spinous process spacers lacked sufficient evidence to support efficacy.

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Medial branch blocks and facet joint injections were found to be useful diagnostic tools.

Impact of Sleep Disturbance on Clinical Outcomes in Lumbar Decompression

OBJECTIVE

To examine the impact of Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance (PROMIS-SD) on clinical outcomes in patients undergoing lumbar decompression.

METHODS

Patients undergoing lumbar decompression with preoperative PROMIS-SD scores were retrospectively included. Patients were separated into 2 cohorts: none to slight sleep disturbance (PROMIS-SD <55) and mild to severe sleep disturbance (PROMIS-SD ≥55). Patient-reported outcome measures including PROMIS Physical Function, PROMIS Anxiety, PROMIS Pain Interference, PROMIS SD, 9-item Patient Health Questionnaire, visual analog scale back/leg, and Oswestry Disability Index were collected preoperatively and up to 1 year postoperatively.

RESULTS

Of 87 patients identified, 48 patients had PROMIS-SD scores ≥55. Regardless of preoperative PROMIS-SD score, patients reported significant improvement in physical function, anxiety, pain interference, depression, pain, and disability outcomes in at least 1 time point. Patients in the PROMIS-SD ≥55 cohort reported postoperative improvement in sleep disturbance. Patients in the PROMIS-SD <55 cohort reported superior preoperative patient-reported outcome measures in all domains and superior postoperative improvement in pain interference and sleep disturbance. Minimum clinically important difference attainment rates were higher in the PROMIS-SD ≥55 cohort in physical function, anxiety, pain interference, sleep disturbance, and pain.

CONCLUSIONS

Patients undergoing lumbar decompression demonstrated significant postoperative improvement in most clinical outcomes regardless of preoperative sleep disturbance. Patients with mild to severe sleep disturbance had higher minimum clinically important difference attainment rates for physical function, mental function, and pain. Patients undergoing lumbar decompression with greater preoperative sleep disturbance may experience more clinically noticeable improvement.

The American Society of Pain and Neuroscience (ASPN) Evidence-Based Clinical Guideline of Interventional Treatments for Low Back Pain

Introduction

Painful lumbar spinal disorders represent a leading cause of disability in the US and worldwide. Interventional treatments for lumbar disorders are an effective treatment for the pain and disability from low back pain. Although many established and emerging interventional procedures are currently available, there exists a need for a defined guideline for their appropriateness, effectiveness, and safety.

Objective

The ASPN Back Guideline was developed to provide clinicians the most comprehensive review of interventional treatments for lower back disorders. Clinicians should utilize the ASPN Back Guideline to evaluate the quality of the literature, safety, and efficacy of interventional treatments for lower back disorders.

Methods

The American Society of Pain and Neuroscience (ASPN) identified an educational need for a comprehensive clinical guideline to provide evidence-based recommendations. Experts from the fields of Anesthesiology, Physiatry, Neurology, Neurosurgery, Radiology, and Pain Psychology developed the ASPN Back Guideline. The world literature in English was searched using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Scopus, and meeting abstracts to identify and compile the evidence (per section) for back-related pain. Search words were selected based upon the section represented. Identified peer-reviewed literature was critiqued using United States Preventive Services Task Force (USPSTF) criteria and consensus points are presented.

Results

After a comprehensive review and analysis of the available evidence, the ASPN Back Guideline group was able to rate the literature and provide therapy grades to each of the most commonly available interventional treatments for low back pain.

Conclusion

The ASPN Back Guideline represents the first comprehensive analysis and grading of the existing and emerging interventional treatments available for low back pain. This will be a living document which will be periodically updated to the current standard of care based on the available evidence within peer-reviewed literature.

Meeting Patient Expectations and Achieving a Minimal Clinically Important Difference for Back Disability, Back Pain, and Leg Pain May Provide Predictive Utility for Achieving Patient Satisfaction Among Lumbar Decompression Patients

OBJECTIVE

Our study evaluates minimum clinically important difference (MCID) achievement for back pain/leg pain/disability and meeting preoperative expectations as predictors of patient satisfaction after minimally invasive lumbar decompression (MIS-LD) surgery.

METHODS

Single/multilevel MIS-LD procedures were identified. Patient-reported outcome measures (preoperative/postoperative), expectations (preoperative), and satisfaction (postoperative) were collected for visual analog scale (VAS) back/VAS leg/Oswestry Disability Index (ODI). Student's t-test assessed patient-reported outcome measure improvement from preoperative baseline. Correlations between outcome and satisfaction scores were evaluated using the Pearson correlation coefficient and categorized according to strength of relationship. MCID achievement and meeting expectations were evaluated as predictors of postoperative patient satisfaction with simple linear regression. Comparison of meeting expectations or achieving MCID as predictors of satisfaction scores was performed using a post hoc Suest test comparison of standardized β-coefficients.

RESULTS

A total of 329 patients were included. All outcomes improved from baselines (P < 0.001, all) at all postoperative time points and demonstrated strong and negative correlations with satisfaction scores (P < 0.001, all). Majority of patients had their expectations met for ODI/VAS back/VAS leg and achieved MCID for ODI/VAS back/VAS leg at all time points and overall. Both MCID achievement and meeting preoperative expectations demonstrated significant associations with satisfaction scores at all time points for ODI/VAS back/VAS leg. Post hoc analysis of predictors of patient satisfaction in pain and disability demonstrated that MCID achievement was an equivalent predictor to meeting patient preoperative expectations at all postoperative time points.

CONCLUSION

Pain/disability improved after MIS-LD; improvement was strongly correlated with postoperative satisfaction. Meeting expectations/MCID achievement is associated with satisfaction. MCID achievement was equivalent to meeting expectations in predicting satisfaction at all postoperative time points for pain/disability.

Best Practices for Minimally Invasive Lumbar Spinal Stenosis Treatment 2.0 (MIST): Consensus Guidance from the American Society of Pain and Neuroscience (ASPN)

Introduction

Methods

Results

Discussion

Conclusion

The MOTION Study: A Randomized Controlled Trial with Objective Real-World Outcomes for Lumbar Spinal Stenosis Patients Treated with the mild® Procedure: One-Year Results

OBJECTIVE

The purpose of this study is to provide Level-1 objective, real-world outcome data for patients with lumbar spinal stenosis suffering from neurogenic claudication secondary to hypertrophic ligamentum flavum.

DESIGN

The MOTION Study is a prospective, multicenter, randomized controlled trial comparing the mild® Procedure (minimally invasive lumbar decompression; Vertos Medical, Aliso Viejo, CA, USA) as a first-line therapy in combination with nonsurgical conventional medical management (CMM) vs CMM alone as the active control.

METHODS

Patients in the test group received the mild Procedure at baseline. Both the mild+CMM group and the control group were allowed unrestricted access to conventional real-world therapies. Patient-reported outcomes included the Oswestry Disability Index, the Zurich Claudication Questionnaire, and the Numeric Pain Rating Scale. A validated Walking Tolerance Test, the incidence of subsequent lumbar spine interventions, and the occurrence of adverse events were used to measure objective outcomes.

RESULTS

Sixty-nine patients in each group were analyzed at 1-year follow-up. No device- or procedure-related adverse events were reported in either group. Results from all primary and secondary outcome measures showed statistical significance in favor of mild+CMM.

CONCLUSIONS

One-year results of this Level-1 study demonstrated superiority of mild+CMM over CMM alone for patients with lumbar spinal stenosis who were suffering from neurogenic claudication secondary to hypertrophic ligamentum flavum. Use of the validated Walking Tolerance Test to objectively measure increased ability to walk without severe symptoms provided evidence of statistically significantly better outcomes for mild+CMM than for CMM alone. With no reported device or procedure-related adverse events, the long-standing safety profile of the mild Procedure was reaffirmed. mild is a safe, durable, minimally invasive procedure that has been shown to be effective as an early interventional therapy for patients suffering from symptomatic lumbar spinal stenosis.

Change in Patient-Reported Outcome Measures as Predictors of Revision Lumbar Decompression Procedures

Objective

To assess change in Patient-Reported Outcome Measures (PROM) as predictors for revision lumbar decompression (LD).

Methods

Patients who underwent primary, single or multilevel LD were retrospectively reviewed. Patients were categorized according to whether or not they underwent revision LD within 2 years of the primary procedure. Visual analogue scale (VAS), Oswestry Disability Index (ODI), 12-item Short Form Health Survey and 12-item Veterans RAND physical component score (SF-12 PCS and VR-12 PCS), and Patient-Reported Outcome Measurement Information System physical function (PROMIS-PF) were recorded. Delta PROM scores were evaluated for differences between groups and as a risk factor for a revision LD.

Results

The study included 135 patients, 91 undergoing a primary procedure only and 44 undergoing a primary and revision procedure. Matched patients did not demonstrate any significant differences in demographics or perioperative characteristics. Patients who underwent a revision had a mean time to revision of 7.4 ± 5.7 months. Primary cohort significantly improved for all PROMs (all p < 0.05), while the primary plus revision cohort significantly improved for VAS back, ODI, and PROMIS-PF (all p < 0.05). However, cohorts differed in VAS back and PROMIS-PF (p < 0.05). Delta PROMs were not a significant risk factor for revision except at 6 months for PROMIS-PF (p = 0.024).

Conclusion

LD has been associated with reliable outcomes, but early identification of patients at risk for revision is critical. This study suggests that tools such as PROMIS-PF may serve a role in predicting who is at risk and the 6-month follow-up period may be valuable for counseling patients who are not experiencing improvement.

Minimally invasive direct decompression for lumbar spinal stenosis: impact of multiple prior epidural steroid injections

Background: A modified algorithm for the treatment of lumbar spinal stenosis with hypertrophic ligamentum flavum using minimally-invasive lumbar decompression (mild^®)was assessed, with a focus on earlier intervention. Patients & methods: Records of 145 patients treated with mild after receiving 0-1 epidural steroid injections (ESIs) or 2+ ESIs were retrospectively reviewed. Pain assessments as measured by visual analog scale (VAS) scores were recorded at baseline and 1-week and 3-month follow-ups. Results: Improvements in VAS scores at follow-ups compared with baseline were significant in both groups. No statistically significant differences were found between the two groups. Conclusion: Multiple ESIs prior to mild showed no benefit. A modified algorithm to perform mild immediately upon diagnosis or after the failure of the first ESI is recommended.

A Retrospective, Single-Center, Quantitative Analysis of Adverse Events in Patients Undergoing Spinal Stenosis with Neurogenic Claudication Using a Novel Percutaneous Direct Lumbar Decompression Strategy

Introduction

Low-back pain with accompanying neurogenic claudication is a common diagnosis in pain and spine centers around the world, with an evolving algorithm of treatment. One option for the treatment of neurogenic claudication by decompressive strategies centers on percutaneous direct decompressive techniques. Although commonly employed in clinical practice, there have been no formal investigations looking at safety of percutaneous direct decompression without the use of an epidurogram and relying on osteal landmarks. The purpose of this study was to investigate the safety of percutaneous direct decompression performed without the use of the epidurogram.

Methods

After an IRB exemption had been obtained from the Western Investigational Review Board, data were retrospectively analyzed from July 2018 to August 2020 on patients that had undergone percutaneous direct decompression using the Mild procedure in a single center by a single physician. Data were analyzed quantitatively for reported complications within 3 months of the procedure, including nerve injury, hematoma, infection, death, or allergic reaction to contrast use.–

Results

Chart review yielded 147 individual patients who had undergone percutaneous direct decompression from July 2018 to August 2020. In this data set, women outnumbered men, with an average age of 76 years, with L4–L5 followed by L3–L4 being the most common levels decompressed. Of the 147 patients was performed, utilizing an epidurogram versus no epidurogram for decompression, with no complications. These data are the first to describe the safety of percutaneous direct lumbar decompression without the use of contrast.

Conclusion

This study strongly suggests the use of an epidurogram is not necessary for the safe decompression of a patient with symptomatic spinal stenosis and neurogenic claudication utilizing percutaneous direct decompression.

Objective Real-World Outcomes of Patients Suffering from Painful Neurogenic Claudication Treated with the mild® Procedure: Interim 6-Month Report of a Randomized Controlled Trial

Background

Lumbar spinal stenosis (LSS) is a serious degenerative condition of the spine that can cause significant functional disability. Therapies for these patients generally begin with conservative management, since more invasive interventions such as open surgery and spinal implants are associated with higher complication rates. Early in the treatment algorithm for LSS patients, multiple conventional medical management (CMM) therapies are often combined as an initial low-risk treatment strategy. This composite first-line treatment plan may include conservative care together with early interventional treatment options such as epidural steroid injections, radiofrequency ablation and the mild^® Procedure.

Methods

This prospective randomized controlled trial evaluates patients aged 50 to 80 years treated with mild plus CMM, compared to those treated with CMM alone, as the active control. Walking tolerance test outcomes and incidence of subsequent disallowed procedures provided objective real-world outcome data. The incidence of device or procedure-related adverse events was analyzed. Follow-up includes 6-month, 1-year and 2-year assessments, with 1-year being primary. Patients in the mild+CMM group are followed at 3, 4, and 5 years. This is a report of interim 6-month outcomes.

Results

Of 155 patients enrolled at 19 US interventional pain management centers, 78 were allocated to CMM-Alone, and 77 to mild+CMM. At 6-months, the validated walking tolerance test demonstrated statistical superiority of mild+CMM versus CMM-Alone (p<0.001). The incidence of patients receiving a subsequent disallowed procedure, and thereby considered treatment failures in their study group, was statistically significantly higher in CMM-Alone versus mild+CMM (p<0.001). There were no device or procedure-related adverse events in either group.

Conclusion

At 6-months, the mild Procedure combined with CMM provided statistically superior objective real-world outcomes versus CMM-Alone. There were no device or procedure-related adverse events reported in either study group. With its excellent safety profile and superior efficacy, mild is uniquely positioned as early first-line therapy.

Welcome to the 11th Volume of Pain Management

I would like to welcome our readers to volume 11 of Pain Management. Since the launch of the journal in 2011, the title has gone from strength to strength, and we are delighted to bring you a new year of content. We are starting off this issue with a look back on some of our article highlights from 2020, alongside some of this month's key content.