Axillary nerve: what anesthesiologists and pain physicians should know

Innervation of the shoulder joint is complex and remains poorly understood among regional anesthesiologists and chronic pain specialists. Current literature supports the important contribution of the axillary nerve to the total innervation of the shoulder, as well as its blockade for perioperative pain and denervation for chronic shoulder pain. However, a description of the entire course of the axillary nerve, the corresponding optimal targets, and the sonoanatomy pertinent to pain intervention is lacking. This educational article discusses in detail the functional anatomy and sonographic identification of possible windows for axillary nerve intervention. We discuss the contribution, extent, and type of innervation the axillary nerve provides to the shoulder joint, which is often misunderstood. Ultimately, this article serves to stimulate thoughts and ideas for future research in an area where literature is scarce.

Minimally invasive interventional procedures for osteoarthritis and inflammatory arthritis: A systematic review and meta-analysis

OBJECTIVE

to summarize the evidence on the efficacy of minimally invasive interventional procedures such as radiofrequency ablation (RFA) and transcatheter arterial embolization (TAE) in patients with osteoarthritis or inflammatory arthritis.

METHODS

a literature search was conducted in PubMed and Web of Science databases. Both randomized controlled trials (RCTs) and non-randomized studies of interventions (NRSI) were included. The results were organized according to the treated anatomical site: knee, hip, foot and ankle, shoulder, hand and wrist, sacroiliac joints. Data about treatment efficacy were extracted. The main outcome was change in pain intensity using the 0-10 visual analog scale (VAS) from baseline to 1 month. Additional timepoints at 3, 6 and 12 months were assessed. Change in functional status was evaluated. Pooled estimates were calculated as the mean difference (MD) and 95 % confidence interval relative to baseline. The meta-analyses of RCTs and NRSI were conducted separately.

RESULTS

of the 4599 retrieved articles, 164 were included in the review and, considering all the established timepoints, 111 (38 RCTs and 73 NRSI) were selected for the meta-analysis. Only one article described patients with inflammatory arthritis. In the meta-analysis of RCTs, one month after the procedure, MD in VAS was -3.98 (-4.41 to -3.55; k = 21) for knee RFA, and -3.18 (-3.96 to -2.39; k = 8) for sacroiliac joints RFA. In the meta-analysis of NRSI, MD in VAS was -4.12 (-4.63 to -3.61; k = 23) for knee RFA, -3.84 (-4.77 to -2.92; k = 7) for knee TAE, -4.34 (-4.96 to -3.71; k = 2) for hip RFA, -3.83 (-4.52 to -3.15; k = 3) for shoulder RFA and -4.93 (-5.58 to -4.28; k = 14) for sacroiliac joints RFA. Significant decrease in pain intensity was found also at 3, 6 and 12 months. Additionally, functional status improved at all the assessed timepoints.

CONCLUSION

minimally invasive interventional procedures can improve pain and functional status of patients affected by OA or chronic sacroiliac pain of degenerative origin. Further research is warranted in the field of inflammatory rheumatic diseases.

Two-Centre Retrospective Analysis on Selective Sensory Denervation of Shoulder Joint by Means of Cooled Radiofrequency in Chronic Shoulder Pain

Purpose

Radiofrequency ablation has been used to treat chronic shoulder pain with mixed results. Thanks to recent anatomical studies, the precise location of articular branches of the suprascapular, lateropectoral and axillary nerves has been determined. Cooled radiofrequency is a neuroablative modality of treatment which has been demonstrated as efficient in different anatomical locations, and targeting the aforementioned nerves could result in a complete and efficient denervation of the shoulder. The aim of this study is to assess the efficacy of a fluoroscopic guided cooled radiofrequency technique for chronic shoulder pain.

Patients and Methods

This is a retrospective observational study performed in two hospital in Wales and Italy (Wrexham NHS trust and Iseo Hospital). Forty-four patients were treated between December 2019 and January 2023. Follow-up was provided at 1-, 6- and 12-months post-procedure. Pain intensity was measured with a 0-10-point Numerical Rating Scale (NRS), and was assessed at rest and during movement. Disability was assessed with the Oxford Shoulder Score (OSS). All patients were treated with cooled radiofrequency under fluoroscopic guidance targeting the articular branches of the suprascapular, axillary and lateropectoral nerves.

Results

In the 44 patients treated, the mean NRS significantly decreased at all follow ups, pain relief of >50% was obtained in 70.4%, 61% and 51% of the patients at 1.6 and 12 month follow-ups, respectively. Disability improved significantly, with a mean OSS at 12 months follow up of 30 ±17.5, compared to 15 ± 3 at baseline. Medication intake (non-steroidal anti-inflammatory drugs (NSAIDS) and/or opioids) significantly decreased at all follow ups.

Conclusion

Cooled radiofrequency denervation can be an effective procedure to manage chronic shoulder pain, providing sustained pain relief and functional improvement in more than 50% of the patients.

Shoulder terminal sensory articular nerve radiofrequency ablation for nonsurgical refractory shoulder pain due to rotator cuff pathology and osteoarthritis: a technical note

BACKGROUND

Given the high prevalence of chronic shoulder pain and encouraging early results of terminal sensory articular branch radiofrequency ablation to treat shoulder pain, research is warranted to refine the procedural technique on the basis of updated neuroanatomic knowledge with the goal of further improving patient outcomes.

OBJECTIVE

We describe an updated radiofrequency ablation protocol that accounts for varied locations of the terminal sensory articular branches of the suprascapular, axillary, subscapular, and lateral pectoral nerves within individual patients.

DESIGN

Technical note.

METHODS

Cadaveric studies delineating the sensory innervation of the shoulder joint were reviewed, and a more comprehensive radiofrequency ablation protocol is proposed relative to historical descriptions.

CONCLUSIONS

The proposed radiofrequency ablation protocol, which is based on neuroanatomic dissections of the shoulder joint, will provide a safe means of more complete sensory denervation and potentially improve clinical outcomes compared with historical descriptions, the efficacy of the new protocol must be confirmed in prospective studies.

Ultrasound-guided pulsed radiofrequency for chronic shoulder pain: a prospective study

BACKGROUND AND OBJECTIVES

Chronic shoulder pain is a frequent cause of suffering and impaired quality of life. Treatment includes non-pharmacological and pharmacological therapies, and interventional procedures such as suprascapular nerve blocks and radiofrequency. This prospective study aims to evaluate the efficacy of ultrasound-guided pulsed radiofrequency of suprascapular nerve for chronic shoulder pain in a clinical setting.

METHODS

Therapeutic efficacy was evaluated through pain intensity using numeric pain rating scale at baseline, immediately, 3, and 6 months after, and patient...s motor function improvement. The secondary outcome was patient satisfaction.

RESULTS

A total of 34 patients were enrolled and all patients presented a reduction in the numeric pain rating scale immediately after treatment. Pain reduction from baseline to 6 months after the procedure was 34.4% and 36.9% static and dynamic, respectively. The median percentage reduction was statistically significant immediately, 3 and 6 months after. There was also an improvement in range of motion, 39.6% in abduction, 24.1% in flexion, and 29.5% in extension. Ninety percent of patients reported patient...s global impression of change superior to six.

CONCLUSION

This study concludes that ultrasound-guided pulsed radiofrequency of suprascapular nerve reduces pain intensity for at least 6 months, accompanied by improvement of motor function and higher levels of patients... satisfaction. Therefore, this technique represents a valid analgesic approach to chronic shoulder pain.

Image-Guided Radiofrequency Ablation for Joint and Back Pain: Rationales, Techniques, and Results

Image-guided minimally invasive radiofrequency ablation (RFA) of sensory nerves has emerged as a treatment option for pain and swelling associated with advanced symptomatic joint and spine degeneration to bridge the gap between optimal medical therapy and surgical treatments. RFA of articular sensory nerves and the basivertebral nerve use image-guided percutaneous approaches resulting in faster recovery time and minimal risks. The current published evidence indicates clinical effectiveness; however, further research must be performed comparing other conservative treatments with RFA to understand further its role in different clinical settings, such as osteonecrosis. This review article discusses and illustrates the applications of RFA for treating symptomatic joint and spine degeneration.

Phenolysis for Advanced Shoulder Osteoarthritis: A Case Series of a Novel Ultrasound-Guided Approach to Anterior and Posterior Glenohumeral Articular Nerve Branches

INTRODUCTION

The shoulder is one of the joints most affected by osteoarthritis, with a prevalence of almost 20% in adults over 65 years of age. Various treatments have been proposed to control osteoarthritis pain, including radiofrequency, pulsed and thermal, and recently cryoanalgesia. We propose in this series of cases a new approach to analgesic therapy with chemical denervation with phenol.

MATERIALS AND METHOD

Patients who underwent phenolysis for shoulder osteoarthritis at our institutions in Italy and Australia between August 2022 and May 2023 were included. All patients included in our report provided written consent for publication. This chemical neurolysis technique consisted of two injections. First, the anterior shoulder capsule was denervated by a modified deep SHAC (Shoulder Anterior Capsule) approach to cover the anterior terminal articular branches of the axillary nerve, lateral pectoral nerve, and subscapularis nerve. Second, the posterior shoulder capsule was denervated by a posterior glenoid approach to cover the terminal articular branches of the suprascapular nerve (SSN).  Results: We included a total of 11 patients in this case series. Ten of 11 patients were affected by shoulder osteoarthritis, of which three had rotator cuff tendinopathy and three had full-thickness cuff tears. One patient had chronic subluxation of a shoulder prosthesis. After treatment, all patients significantly reduced pain immediately after treatment and, two weeks later, recovered joint movement and improved quality of life. No adverse events or loss of motor function following treatment.

CONCLUSION

We presented a novel chemical approach to shoulder denervation, which was shown to be another effective way of improving pain and function in advanced glenohumeral arthritis.

Pilot study for treatment of symptomatic shoulder arthritis utilizing cooled radiofrequency ablation: a novel technique

OBJECTIVE

To introduce cooled radiofrequency nerve ablation (C-RFA) as an alternative to managing symptomatically moderate to severe glenohumeral osteoarthritis (OA) in patients who have failed other conservative treatments and who are not surgical candidates or refuse surgery.

MATERIAL AND METHODS

This prospective pilot study includes a total of 12 patients experiencing chronic shoulder pain from moderate to severe glenohumeral OA. Patients underwent anesthetic blocks of the axillary, lateral pectoral, and suprascapular nerves to determine candidacy for C-RFA treatment. Adequate response after anesthetic block was over 50% immediate pain relief. Once patients were deemed candidates, they underwent C-RFA of the three nerves 2-3 weeks later. Treatment response was evaluated using the clinically validated American Shoulder and Elbow Surgeons (ASES) score and visual analog scale (VAS) to assess pain, stiffness, and functional activities of daily living. Follow-up outcome scores were collected up to 6 months after C-RFA procedure.

RESULTS

Twelve patients underwent C-RFA procedure for shoulder OA. VAS scores significantly improved from 8.8 ± 0.6 to 2.2 ± 0.4 6 months after the C-RFA treatment (p < 0.001). Patient's ASES score results significantly improved in total ASES from 17.2 ± 6.6 to 65.7 ± 5.9 (p < 0.0005). No major complications arose. No patients received re-treatment or underwent shoulder arthroplasty.

CONCLUSION

Image-guided axillary, lateral pectoral, and suprascapular nerve C-RFA has minimal complications and is a promising alternative to treat chronic shoulder pain and stiffness from glenohumeral arthritis.

The painful shoulder arthroplasty: appropriate work-up and review of interventional pain treatments

Shoulder arthroplasty is a successful surgical procedure for several conditions when patients become refractory to conservative management modalities. Unfortunately, some patients experience persistent chronic pain after shoulder arthroplasty. These individuals should undergo a comprehensive evaluation by an orthopedic surgeon to determine whether structural pathology is responsible for the pain and to decide whether reoperation is indicated. At times, a surgical solution does not exist. In these circumstances, a thorough and specific plan for the management of persistent chronic pain should be developed and instituted. In this article, we review common reasons for persistent pain after shoulder arthroplasty and outline the evaluation of the painful shoulder arthroplasty. We then provide a thorough review of interventional pain management strategies. Finally, we hypothesize developments in our field that might provide better outcomes in the future for patients suffering with chronic intractable pain after shoulder arthroplasty.

Alternative treatment of hip pain from advanced hip osteoarthritis utilizing cooled radiofrequency ablation: single institution pilot study

OBJECTIVE

To establish the effectiveness of cooled radiofrequency ablation in managing hip pain from osteoarthritis at 6 months after receiving treatment in patients who failed conservative treatments and are not surgical candidates due to comorbidities or unwillingness to undergo arthroplasty surgery by targeting the femoral and obturator branches and assessing the degree of hip pain relief and change of function.

MATERIALS AND METHODS

This prospective pilot study includes a total of 11 consecutive patients experiencing persistent chronic hip pain in the setting of advanced osteoarthritis. Patients initially underwent anesthetic blocks of the obturator and femoral nerve branches to determine cooled radiofrequency ablation candidacy. After adequate response to the anesthetic blocks (> 50% immediate pain relief), patients were subjected to the procedures 2-3 weeks later. Treatment response was evaluated utilizing clinically validated questionnaires and visual analog score in order to assess impact on pain severity, stiffness, and functional activities of daily living. Follow-up outcome scores were collected up to 6 months after cooled radiofrequency ablation procedure.

RESULTS

A total of 11 hips were treated consecutively between August 2019 and March 2020 (mean patient age 61.4 years; 8 M:3F). The mean total HOOS score improved significantly from baseline at 17.0 ± 6.0 to 52.9 ± 5.4 at a mean of 6.2 months after treatment (p < 0.0001), with significant improvement in mean pain score from 16.1 ± 6.6 to 53.4 ± 7.4 (p < 0.0001) and mean stiffness score from 15.0 ± 8.1 to 53.6 ± 11.0 (p < 0.0001). No major complications were encountered. No patients went on to re-treatment, surgery, or other intervention.

CONCLUSION

Image-guided obturator and femoral nerve cooled radiofrequency ablation is effective and safe in treating chronic hip pain/stiffness in the setting of advanced osteoarthritis.

Cooled Radiofrequency Ablation for Chronic Joint Pain Secondary to Hip and Shoulder Osteoarthritis

Osteoarthritis (OA) of the shoulder and hip is a leading cause of physical disability and mental distress. Traditional nonsurgical management alone is often unable to completely address the associated chronic joint pain. Moreover, a large number of patients are not eligible for joint replacement surgery owing to comorbidities or cost. Radiofrequency ablation (RFA) of articular sensory nerve fibers can disrupt the transmission of nociceptive signals by neurolysis, thereby providing long-term pain relief. A subtype of RFA, cooled RFA (CRFA), utilizes internally cooled electrodes to generate larger ablative zones compared with standard RFA techniques. Given the complex variable innervation of large joints such as the glenohumeral and hip joints, a larger ablative treatment zone, such as that provided by CRFA, is desired to capture a greater number of afferent nociceptive fibers. The suprascapular, axillary, and lateral pectoral nerve articular sensory branches are targeted during CRFA of the glenohumeral joint. The obturator and femoral nerve articular sensory branches are targeted during CRFA of the hip. CRFA is a promising tool in the interventionalist's arsenal for management of OA-related pain and symptoms, particularly in patients who cannot undergo, have long wait times until, or have persistent pain following joint replacement surgery. An invited commentary by Tomasian is available online. ^©RSNA, 2022.

A Novel Treatment Approach of Ultrasound-Guided Radiofrequency Ablation of the Greater Trochanteric Sensory Nerve for Recalcitrant Greater Trochanteric Pain Syndrome

This report describes a novel technique for the treatment of recalcitrant greater trochanteric pain syndrome (GPTS) by radiofrequency ablation (RFA) of the greater trochanteric sensory nerve (GTsn). Here, we describe one patient suffering from recalcitrant GTPS treated with RFA of the GTsn in the outpatient pain clinic setting. Over the eight months subsequent to treatment, the patient was monitored for changes in the Numerical Pain Rating (NPR) and Lower Extremity Functional Score (LEFS). The patient demonstrated meaningful symptomatic and functional improvement as measured by both NPR and LEFS. GTsn RFA may be a viable treatment option for recalcitrant GTPS. Larger comparative trials are needed to establish improved results over conventional treatments.

Review of Extraosseous Applications of Thermal Ablation in the Treatment of Moderate to Severe Large Joint Osteoarthritis

Osteoarthritis (OA) is the most common joint disease worldwide, leading to significant pain, restricted range of motion, and disability. A gap exists between short- and long-term symptom-relieving therapies. Although arthroplasty is an effective treatment for symptomatic end-stage disease, most patients ultimately do not receive a joint replacement due to suboptimal surgical qualifications, comorbidities, or an aversion to surgery. The lack of additional treatment options in this setting makes opioid agonists a commonly used pharmacologic agent, contributing to the addiction epidemic that greatly afflicts our communities. Cooled radiofrequency ablation (CRFA) has arisen as a treatment modality in the setting of moderate to severe OA among patients refractory to conservative management, generally showing greater efficacy compared with other existing strategies. This review focuses on the benefits of CRFA and its technical feasibility as a management option among patients experiencing debilitating large joint OA with limited clinical options.

Shoulder Ablation Approaches

The shoulder is structurally and functionally complex. Shoulder pain may be refractory to conventional treatments, such as physical therapy, pharmacotherapy, and corticosteroid injections. In such cases, radiofrequency ablation may serve as an alternative treatment plan. Current literature has demonstrated 4 target nerves for ablative therapy: the suprascapular nerve, axillary nerve, lateral pectoral nerve, and subscapular nerve. Special caution is needed when targeting these nerves in order to avoid motor denervation. This article summarizes the current evidence for radiofrequency ablation as a useful treatment option for chronic shoulder pain as well as the described techniques for performing this promising procedure.

New ultrasound-guided techniques in chronic pain management: an update

PURPOSE OF REVIEW

The introduction of ultrasound guidance in interventional pain management leads to the development of new interventional pain management techniques. Ultrasound-guided (UG) interventional pain management is rapidly developing and increasingly more commonly used, due to its many advantages over traditional radiologic imaging modalities. This review will summarize recent literature around novel interventional pain techniques with ultrasound guidance published over the last 18 months.

RECENT FINDINGS

Many new interventional pain management methods have been described in the last few years in the literature. The use of ultrasonography in interventional pain management played a crucial role in these developments. This review includes newly described interventional methods in the literature. The review particularly focussed on the methods that are used to treat the pain in the hip, shoulder, knee, and lumbar area. These new techniques hold promise for significant improvements in the efficacy and safety of interventional pain management.

SUMMARY

There have been many innovations in UG interventional procedures, however, some of them require more rigorous validation before their widespread use.

Putting Our Shoulder to the Wheel: Current Understanding and Gaps in Nerve Ablation for Chronic Shoulder Pain

Shoulder pain is prevalent, burdensome, and functionally limiting, with diverse pathology and associated treatments. This narrative review provides a summary of relevant neuroanatomy, proposed ablation targets, safety and efficacy concerns for ablation targets, and current research gaps. Radiofrequency ablation (RFA) of peripheral sensory nerves is a well-established treatment for chronic joint and spine pain, but it is relatively nascent for shoulder pain. Cadaveric studies demonstrate the shoulder joint is innervated by articular branches of the suprascapular nerve, axillary nerve, lateral pectoral nerve, and upper and lower subscapular nerves. Shoulder articular branch RFA appears to be a safe and effective treatment for chronic shoulder pain, but there are currently no widely accepted protocols for ablation targets. There are also no randomized controlled trials (RCT) assessing safety and efficacy of proposed targets or the prognostic value of articular blocks. Future research studies should prioritize categorical data, use appropriate functional measures as primary endpoints, and would ideally include a large-scale RCT.