Suprascapular nerve block: a narrative review

The suprascapular nerve block (SScNB) is easily administered using a landmark-based technique: A cadaveric study to assess nerve staining post-injection

Aims

The suprascapular nerve is an ideal target for nerve blockade to alleviate shoulder pain given its widespread innervation to the shoulder girdle. To widen availability of this treatment, we investigate whether an anatomical landmark technique can be adopted by novice injectors to provide efficacious blockade.

Methods

Five injectors were recruited with varying experience. 10 shoulders of Thiel embalmed cadavers were injected with blue dye. Written instructions and an illustration of the Dangoisse landmark technique were provided prior to injection. Cadavers were dissected and the presence or absence of dye staining reported by three observers and a consensus agreement reached.

Results

Dissection demonstrated diffuse staining in the suprascapular fossa. 90% of shoulders had adequate staining of the suprascapular nerve directly, or distal branches, which would provide adequate anaesthesia. Inter-observer agreement was good (k = 0.73) for staining at the supraspinous fossa and excellent (k = 0.87) for staining distally. The technique was performed by novice injectors with a good success rate.

Conclusion

This technique is reproducible by a range of clinicians to effectively provide anaesthesia of the SScN. Within a resource strained healthcare environment greater uptake of this technique is likely to be of benefit to a wider group of patients.

Anesthesia for the Patient Undergoing Shoulder Surgery

Shoulder surgery introduces important anesthesia considerations. The interscalene nerve block is considered the gold standard regional anesthetic technique and can serve as the primary anesthetic or can be used for postoperative analgesia. Phrenic nerve blockade is a limitation of the interscalene block and various phrenic-sparing strategies and techniques have been described. Patient positioning is another important anesthetic consideration and can be associated with significant hemodynamic effects and position-related injuries.

Comparative Randomized Study Between Pulsed Radiofrequency and Suprascapular Nerve Block for the Treatment of Chronic Shoulder Pain

OBJECTIVES

The primary objective of this study was to compare pain intensity after pulsed radiofrequency (RF) or suprascapular nerve block for the treatment of chronic shoulder pain. The secondary objectives were to compare the shoulder range of motion and supplementary analgesic requirement.

METHODS

This randomized and prospective study included 40 patients, with chronic shoulder pain allocated into 2 groups. One group underwent pulsed RF, and the other group was submitted to block (B) of the suprascapular nerve, guided by ultrasound. They were assessed for 12 weeks regarding pain intensity, the need for analgesia supplementation, and shoulder range of motion. Side effects were recorded.

RESULTS

Pain intensity on movement was lower in the RF group after 2, 4, and 8 weeks. At rest, pain intensity was lower in group RF than in group B after 12 weeks. Pain intensity was lower than before the procedure at all times evaluated, in both groups. There was no difference between groups in the range of motion. There was a need for tramadol supplementation in 1 patient in group RF and 2 in group B. Adverse effects observed were local pain (RF: 1), hematoma (RF: 1; B: 1), and lipothymia (B: 2).

DISCUSSION

Pulsed RF on the suprascapular nerve promoted an analgesic effect for 12 weeks. Regarding the intensity of pain on movement and at rest, there was a trend toward a better effect with RF than with nerve blockage treatment. In both groups, there was a reduction in pain intensity without serious adverse effects.

Continuous suprascapular nerve blockade to potentiate intensive rehabilitation for refractory adhesive shoulder capsulitis: a cohort study

PURPOSE

Evaluating the short- and long-term efficacy of a continuous ten day suprascapular nerve block combined with daily multidisciplinary rehabilitation on shoulder range of motion (ROM), pain, and function in patients with refractory adhesive capsulitis (AC).

METHODS

In this retrospective cohort study, patients admitted to a specialized pain clinic for refractory AC for more than 6 months underwent continuous suprascapular nerve blockade for ten days and received 2 hours of physiotherapy and occupational therapy daily. Standardized assessments were performed at baseline, at days three, six, ten, 30, 90, and 180, and included active and passive ROM measurements, the visual analog scale (VAS) for pain and the disabilities of the arm, shoulder and hand (DASH) questionnaire to assess pain, disability, and quality of life. Improvements over time were assessed using ANOVAs.

RESULTS

Thirty-two patients were followed (age: 52 ± 8 years, 25 females, mean symptoms duration of two years). There was a significant improvement in ROM for all amplitudes at day ten (short-term; range: 20-35°, p < 0.001) and at day 180 (long-term; range: 18-47°, p < 0.001). The pain and disability scores significantly reduced by day 180 (mean VAS reduction: 2.6 units, p < 0.001; mean DASH reduction: 9.5 points, p < 0.001).

CONCLUSION

Continuous SSNB combined with intensive multidisciplinary rehabilitation represents an efficient therapeutic option for patients with chronic AC who did not respond to conventional treatments.

A Randomized Comparison Between Interscalene and Combined Interscalene-Suprascapular Blocks for Arthroscopic Shoulder Surgery: A Prospective Clinical Study

Background

To compare the analgesic effect of ISB with a combination of ISB-SSNB and patients who were given opioids with PCA without block in adult patients undergoing shoulder surgery, as measured by opioid consumption and pain intensity in the first 24 hours postoperatively.

Methods

Ninety patients who underwent shoulder surgery were randomly divided into three groups. Group I in which ISB was performed and patient-controlled analgesia (PCA) was inserted, Group II with; ISB and SSNB combined, and PCA was inserted, and Group III where; only PCA was used. Visual analog scale (VAS) pain scores at the second, fourth, sixth, 12th, and 24th hours, morphine consumption, additional analgesic requirement, and patient satisfaction were evaluated.

Results

Compared with Group III, the VAS pain score was significantly lower in Group I and Group II at 2, 4, 6, 12, and 24 hours postoperatively. In Group I, the VAS score at rest at the 6th hour was found to be higher than in Group II. The 24-hour total morphine consumption was higher in the control group than in Group I and Group II. The satisfaction score of the control group was lower than Group I and Group II.

Conclusion

The combined application of ISB and SSNB block is beneficial in shoulder surgery to provide both intraoperative and postoperative analgesia and opioid consumption.

Level of Evidence

Level I; Randomized Controlled Trial; Treatment Study.

Infraspinatus-teres minor (ITM) interfascial block: a novel approach for combined suprascapular and axillary nerve block

BACKGROUND

Combined suprascapular and axillary nerve block could be an analgesic option for shoulder pain control. The current description of this technique requires performing the block procedures at two different sites without consideration for catheter placement. We hypothesized that a single site injection to the interfascial plane between the infraspinatus and teres minor would result in an injectate spread to the suprascapular and axillary nerves.

METHODS

We performed 10 injections with this approach using 25 mL dye solution in 10 shoulders of five unembalmed cadavers. Also, we described three case reports, two single-injection cases and one catheter-placement case, using this approach in patients with acute postsurgical pain and chronic pain in their shoulder region.

RESULTS

In cadaveric evaluations, dye spreading to the suprascapular nerves on the infraspinatus fossa and the spinoglenoid notch cephalad and axillary nerves in the quadrilateral space caudally were observed in all injections. In addition, the most posterolateral part of the joint capsule was stained in 8 out of 10 injections. There was no dye spreading on the nerves to the subscapularis or lateral pectoral nerves. Clinically successful analgesia with no adverse events was achieved in all three cases.

CONCLUSION

Our anatomical and clinical observations demonstrated that an injection to the interfascial plane between the infraspinatus and teres minor consistently achieved injectate spreading to both suprascapular and axillary nerves, which innervate the glenohumeral joint.

Assessment of 2 distinct anatomical landmarks for suprascapular nerve injection: a cadaveric study

BACKGROUND

The suprascapular nerve block (SSNB) is a commonly used procedure for the management of pain in various shoulder pathologies. Both image-guided and landmark-based techniques have been utilized successfully for SSNB, though more consensus is needed regarding the optimal method of administration. This study aims to evaluate the theoretical effectiveness of a SSNB at 2 distinct anatomic landmarks and propose a simple, reliable way of administration for future clinical use.

METHODS

Fourteen upper extremity cadaveric specimens were randomly assigned to either receive an injection 1 cm medial to the posterior acromioclavicular (AC) joint vertex or 3 cm medial to the posterior AC joint vertex. Each shoulder was injected with a 10 ml methylene blue solution at the assigned location, and gross dissection was performed to evaluate the anatomic diffusion of the dye. The presence of dye was specifically assessed at the suprascapular notch, supraspinatus fossa, and spinoglenoid notch to determine the theoretic analgesic effectiveness of a SSNB at these 2 injection sites.

RESULTS

Methylene blue diffused to the suprascapular notch in 57.1% of the 1-cm group and 100% of the 3-cm group, the supraspinatus fossa in 71.4% of the 1-cm group and 100% of the 3-cm group, and the spinoglenoid notch in 100% of the 1-cm group and 42.9% of the 3-cm group.

CONCLUSION

Given its superior coverage at the more proximal sensory branches of the suprascapular nerve, a SSNB injection performed 3 cm medial to the posterior AC joint vertex provides more clinically adequate analgesia than an injection site 1 cm medial to the AC junction. Performing a SSNB injection at this location allows for an effective method of anesthetizing the suprascapular nerve.

Impact of Peripheral Nerve Block Technique on Incidence of Phrenic Nerve Palsy in Shoulder Surgery

Peripheral nerve blocks are an increasingly common method of providing postoperative analgesia for shoulder surgeries. However, the standard technique, the interscalene block (ISB), inevitably causes hemidiaphragmatic paresis (HDP), secondary to phrenic nerve palsy. This can cause morbidity in patients with preexisting respiratory compromise, prompting investigation into alternative "phrenic-sparing" nerve blocks. The aim of this review was to give an overview of these blocks and critically evaluate the current literature to determine if any are suitable replacements for ISB. The incidence of HDP and analgesic efficacy were considered. We queried four electronic databases and one register. Twenty-eight original articles were selected for review. The use of ultrasound guidance, lower volumes of local anaesthetic (LA), and injection 4 mm outside the brachial plexus fascia reduced HDP incidence for the ISB; however, no single modification did so sufficiently. While the anterior suprascapular nerve block (SSNB) showed comparable analgesic effects to the ISB, HDP prevalence was also high. The posterior SSNB produced consistently low HDP incidences but also inferior analgesia to ISB, except when combined with an infraclavicular brachial plexus block. The superior trunk block (STB) provided equivalent analgesia to the ISB while reducing HDP incidence, but not significantly. Lower LA volumes consistently led to lower HDP incidence across all blocks, likely due to a reduced ability to spread to the phrenic nerve. Further investigation into the minimum effective volumes of the extrafascial ISB, anterior SSNB, STB, and combined posterior SSNB with infraclavicular block is warranted to determine if any of these blocks can successfully balance HDP prevention with analgesic efficacy.

Stellate Ganglion Block Reduces Anxiety Symptoms by Half: A Case Series of 285 Patients

The stellate ganglion block (SGB) procedure has been used successfully for over twelve years to treat thousands of patients suffering from posttraumatic stress disorder (PTSD). Level 1b evidence supports this use of SGB, but no studies to date have reported specifically on anxiety symptom improvements following SGB. We collected Generalized Anxiety Disorder questionnaire (GAD-7) scores pre-procedure and at 1-week and 1-month post-procedure from 285 patients. The mean baseline GAD-7 score of 15.9 (indicating severe anxiety) declined significantly following SGB treatment. Changes in GAD-7 scores ≥ 4 were considered clinically meaningful. From baseline to 1 week, the GAD-7 scores dropped by 9.0 points (95% CI = 8.3-9.7, p < 0.001, d = 1.8), with 211 (79.6%) patients demonstrating clinically meaningful improvement. Furthermore, from baseline to 1 month, the GAD-7 scores dropped by 8.3 points (95% CI = 7.6-9.0, p < 0.001, d = 1.7), with 200 (75.5%) patients demonstrating clinically meaningful improvement. The stellate ganglion block treatment resulted in a decrease of GAD-7 scores of over twice the minimal clinically important difference in treating anxiety for at least 1 month following SGB. Given the results from this retrospective observational study, larger prospective studies should be conducted to determine the effects of SGB treatment as a novel therapeutic treatment for generalized anxiety disorder and other anxiety disorders.

Regional Anesthesia Techniques for Shoulder Surgery in High-Risk Pulmonary Patients

Patients with pre-existing pulmonary conditions are at risk for experiencing perioperative complications and increased morbidity. General anesthesia has historically been used for shoulder surgery, though regional anesthesia techniques are increasingly used to provide anesthesia and improved pain control after surgery. Relative to regional anesthesia, patients who undergo general anesthesia may be more prone to risks of barotrauma, postoperative hypoxemia, and pneumonia. High-risk pulmonary patients, in particular, may be exposed to these risks of general anesthesia. Traditional regional anesthesia techniques for shoulder surgery are associated with high rates of phrenic nerve paralysis which significantly impairs pulmonary function. Newer regional anesthesia techniques have been developed, however, that provide effective analgesia and surgical anesthesia while having much lower rates of phrenic nerve paralysis, thereby preserving pulmonary function.

Suprascapular Nerve Block (SSNB) improves the outcome in exercise based management of Primary Adhesive Capsulitis (PAC): A prospective randomized comparative study

Background and Aims

Increased pain and associated stiffness hinders the advantages of exercise and process of recovery in primary adhesive capsulitis. We hypothesized that suprascapular nerve block may positively affect the outcome due to its role in pain relief of acute or chronic shoulder pain. We compared the effect of suprascapular nerve block and exercise with only exercise on the recovery of primary adhesive capsulitis.

Material and Methods

A total of 96 patients of both sexes presenting with primary adhesive capsulitis were divided by computer randomization in two equal groups (n = 48). Group A received exercise only and Group B received suprascapular nerve block followed by exercise. Oral paracetamol was given for analgesia as desired. Patients were followed up at 4, 8, 16, and 24 weeks. Pain was assessed by visual analog scale; functional outcome by Shoulder Pain and Disability Index and range of movement by goniometer.

Results

The pain scores and Shoulder Pain and Disability Index scores were significantly lower at all observation points of 4, 8,16, and 24 weeks in Group B than Group A (P < 0.05). The range of movement in all the ranges of forward flexion, extension, internal and external rotation, and abduction at all observation points was significantly higher in Group-B (P < 0.05) compared to Group A. The consumption of analgesics was significantly more in Group A than Group B at 4 and 8 weeks (P = 0.020 and P = 0.044) but comparable at 12 and 24 weeks (P = 0.145 and P = 0.237 respectively).

Conclusion

Combining SSNB with exercise is more effective in treatment of primary adhesive capsulitis than exercise alone and reduces the use of analgesics. SSNB it is effective and safe to use in primary adhesive capsulitis.

The upper extremity regional anaesthesia trifecta: three upper extremity nerve blocks for awake upper-limb surgery in a patient with a history of contralateral pneumonectomy

While regional anaesthesia plays a pivotal role in the perioperative management of patients undergoing upper extremity surgery, its utility can be limited by the risk of hemi-diaphragmatic paresis. Furthermore, each approach to blocking the brachial plexus has associated limitations that may result in incomplete upper extremity anaesthesia. We describe the combination of three upper extremity nerve blocks to achieve surgical anaesthesia of the whole arm for a patient who had previously undergone a contralateral pneumonectomy. On this occasion, she required upper arm lipectomy and arteriovenous fistula formation. Adequate blockade was achieved with no significant perioperative complications. This case demonstrates the potential of this approach for patients with respiratory compromise undergoing upper limb procedures.

Evaluation of intensive rehabilitation under continuous suprascapular nerve blockade for the treatment of refractory adhesive shoulder capsulitis. Case series

INTRODUCTION

Treatment of refractory adhesive shoulder capsulitis is a challenge. This observational retrospective study evaluated the long-term effectiveness of intensive physiotherapy protocol under a continuous peripheral blockade of the suprascapular nerve (cSSNB).

METHOD

We reviewed 29 medical records of patients suffering from adhesive capsulitis and treated with intensive physiotherapy under cSSNB during 10 days. The "disabilities of the arm, shoulder and hand" outcome questionnaire (DASH score) and shoulder movements were recorded at the beginning, 10 days after local anesthetic infusion and three months after.

RESULTS

Twenty six patients significant improved shoulder movements after 10 days of treatment. Sixteen patients were followed completely until 3 months after rehabilitation program. Range of four shoulder motion compatible with a normal daily life was acquired in nine patients at three months. There is no significant difference in shoulder motion between the end of LA infusion and at three months. At the end of infusion, DASH score is significantly decreased to 59.3 (n = 26), and persists three months 42.1 (n = 16). At three months, 33% of the initial population objectively reach the 4 goals, compatible with a correct quality of life.

CONCLUSION

Rehabilitation under cSSNB is associated with a significant long term improvement in shoulder motion and quality of life in patients with adhesive capsulitis. Randomized controlled trials will be necessary to demonstrate our encouraging results.

Osseous suprascapular canal: rare variant that would hinder suprascapular nerve block and posterior surgical approach

PURPOSE

To report atypical anatomical variation of an osseous suprascapular canal, and to elaborate on its clinical significance as a potential anatomical factor that could obscure a direct posterior surgical approach and suprascapular nerve block.

METHODS

Osteological observational study of the scapula with emphasis on the suprascapular space. The pool of investigated sample size was collectively 768 specimens composed of 529 adult dry scapulae (240 paired, 289 un-paired), 54 children dry scapulae, 135 wet scapulae observed during cadaveric dissections, 47 retrospective 3D CT reconstructions, and 3 retrospective full sequence shoulder MRI. The two reported cases came from the 240 (120 skeleton) observed paired scapulae. Furthermore, the osseous suprascapular canal was examined by X-rays and its internal path was exposed by CT sections. A narrative review was conducted to investigate any relevant reports on the subject matter.

RESULTS

Two left dry bone scapulae with unilateral osseous suprascapular canal were found. The incidence of this atypical morphology of an osseous canal is probably five cases reported in three studies including this cases study.

CONCLUSIONS

The reported cases aid in explaining additional possible anatomical factors that could lead to below threshold anesthetic effect in posterior suprascapular nerve block procedures. Therefore, it is more practical to visualize the suprascapular canal by some imaging method before attempting to blindly access the suprascapular nerve in nerve block or posterior surgical approach due to the rare potential existence of an ossified barrier hindering the procedure.

LEVEL OF EVIDENCE

V Basic Science Research.

Suprascapular nerve block for the treatment of adhesive capsulitis: a randomised double-blind placebo-controlled trial

Objective

Adhesive capsulitis is a common painful shoulder condition. Treatment for the condition remains unsatisfactory. Suprascapular nerve block (SSNB) shows promise as a treatment option for adhesive capsulitis but there are no randomised controlled trials that examine its effect on pain or duration of the condition. The objective of this study was to examine the efficacy of SSNB for the management of adhesive capsulitis.

Methods

A randomised double-blind placebo-controlled trial of SSNB and standard therapy versus placebo and standard therapy was performed. In total, 54 patients were enrolled in the study. 27 patients received a glenohumeral joint (GHJ) injection and physiotherapy plus a 3-month SSNB, and 27 patients received a GHJ injection and physiotherapy plus a 3-month placebo injection. Patients were followed to resolution of their symptoms as measured by a combination of range of movement, pain scores, Shoulder Pain and Disability Index (SPADI) scores and perceived recovery scores. The primary outcome measure was time to resolution of symptoms.

Results

Participants who received the SSNB reduced the duration of their symptoms of adhesive capsulitis by an average of 6 months (mean time to resolution 5.4 (95% CI 4.4 to 6.3) months vs 11.2 (95% CI 9.3 to 13) months) in the placebo group. They also had reduced pain scores, improved range of movement and lower SPADI scores compared with the placebo group across all time points.

Conclusion

SSNB reduced the duration of adhesive capsulitis and resulted in improved pain and disability experience for patients.

Trial registration number

Australian New Zealand Clinical Trials Registry (ANCTRN 12615001378516).

Randomized controlled trial of suprascapular nerve blocks for subacute adhesive capsulitis

BACKGROUND

Shoulder pain and loss of function remain a therapeutic challenge in adhesive capsulitis. Suprascapular nerve blocks, a common treatment in adhesive capsulitis, are considered a safe and effective method for the resolution of pain and restoration of shoulder range of motion (ROM). To our knowledge, no data are available on the use of suprascapular nerve blocks in adhesive capsulitis in the subacute phase.

AIM

The aim of this study was to compare the efficacy of ultrasound-guided suprascapular nerve blocks versus saline injections for treating adhesive capsulitis in the subacute phase.

DESIGN

Randomized double-blinded controlled trial; level of evidence 2.

SETTING

Out-patient consultation of Physical and Rehabilitation Medicine in a general hospital.

POPULATION

Thirty-five patients with subacute adhesive capsulitis.

METHODS

Patients were randomly allocated to receive either 3 successive (1-week interval) ultrasound-guided suprascapular nerve blocks with ropivacaine 5 mL 2 mg/mL (intervention group) or ultrasound-guided injections of 5 mL sterile saline solution (NaCl 0.9%) (control group), at the floor of the suprascapular fossa. Primary outcome was shoulder function assessed by the Constant-Murley Score. Secondary outcomes were shoulder ROM and shoulder pain intensity. Assessments were performed before each injection and 4 weeks after the last injection.

RESULTS

A significant increase of Constant-Murley Score (P<0.001), increase of shoulder ROM (all directions: P<0.011) and decrease of pain (P<0.001), were observed over time in both study groups. However, no significant differences were observed between the intervention and the control group.

CONCLUSIONS

Three successive suprascapular nerve blocks did not provide a better outcome than saline injections on shoulder function, ROM, and pain in subacute adhesive capsulitis. These negative findings warrant some considerations on the natural history of adhesive capsulitis, as well as timing, type, and placebo effects of injections.

CLINICAL REHABILITATION IMPACT

The current place of suprascapular nerve blocks in the treatment strategy of adhesive capsulitis needs to be rediscussed.

The Use of a Suprascapular Nerve Block to Facilitate the Reduction of an Anterior Shoulder Dislocation: An Alternative for Elderly and Patients With Cardiopulmonary Comorbidities?

BACKGROUND

Anterior shoulder dislocation is a common presentation to the emergency department (ED). Dislocations are spontaneous or traumatic. Generally, a reduction is performed under procedural sedation and analgesia (PSA). Other approaches include the use of intra-articular lidocaine or, in rare instances, nerve blocks. Here we discuss the case of a 66-year-old female patient who presented with left shoulder pain and limited range of motion after a fall. After discussing potential treatment options to reduce the dislocation, the patient agreed to a nerve block.

DISCUSSION

The dislocation was reduced successfully with a suprascapular nerve block (SSNB) without complications. The duration of the patient's ED stay was shorter than those who had received PSA.

CONCLUSIONS

SSNB could be an alternative method for shoulder dislocation reduction, particularly for patients who are obese, older, or have cardiopulmonary comorbidities.

US for Traumatic Nerve Injury, Entrapment Neuropathy, and Imaging-guided Perineural Injection

US is commonly performed to help diagnose traumatic peripheral nerve injury and entrapment neuropathy, particularly with superficial nerves, where higher spatial resolution provides an advantage over MRI. Other advantages of US include dynamic evaluation, easy contralateral comparison, fewer implant contraindications, less artifact from ferromagnetic debris, and facile needle guidance for perineural injections. The authors review peripheral nerve US for traumatic peripheral nerve injury with an emphasis on injury grading and entrapment neuropathy and describe best-practice techniques for US-guided perineural injections while highlighting specific techniques and indications. Online supplemental material is available for this article. ^©RSNA, 2022.

Ultrasound-Guided Suprascapular Nerve Block at Spinoglenoid Notch and Glenohumeral Joint Hydrodilation

Hydrodilation of the glenohumeral joint is commonly employed as a nonsurgical intervention for the frozen shoulder. Accuracy and pain during the procedure can be regarded as difficulties in performing this procedure. Ultrasonography (USG) guided injection and suprascapular nerve block can improve the accuracy and can decrease pain during the hydrodilation procedure. We present the step-by-step method for performing USG-guided injections for suprascapular nerve block and hydrodilation.

Ultrasound-guided continuous radiofrequency ablation of the suprascapular nerve for chronic shoulder pain secondary to osteoarthritis: a retrospective cohort study

OBJECTIVES

The objective of this study is to retrospectively evaluate the use of ultrasound-guided continuous radiofrequency (CRF) lesioning of the suprascapular nerve for treating chronic shoulder pain, due to osteoarthritis. We describe a modified distal and selective ablation technique in the spinoglenoid notch, with motor and sensory stimulation, which protects the motor branch of the nerve from ablation.

METHODS

A retrospective analysis was performed of patients, who underwent ultrasound-guided CRF lesioning of the suprascapular nerve from October 2013 to January 2020. During the procedure, the CRF electrode is placed in the spinoglenoid notch, at the distal suprascapular nerve capsular branch. Motor and sensory stimulations are used to confirm the position. CRF lesioning is applied up to three times, at 3 different points, for 1 min each time, at 80^° C.

RESULTS

In total, 127 first CRF suprascapular nerve lesioning procedures were performed on 101 patients with chronic shoulder pain secondary to osteoarthritis. One hundred nineteen diagnostic ultrasound-guided suprascapular nerve corticosteroid injections were performed prior to ablation. Mean pre-injection Visual Analogue Scale pain score (VAS) was 8.3, with post-injection VAS score of 4.4 at 24 h and 4.5 at 2 weeks. Mean pre-CRF lesioning VAS pain score was 7.7 with post-CRF lesioning VAS score of 4.4 at 24 h and 4.5 at 2 weeks.

CONCLUSIONS

Ultrasound-guided CRF lesioning of the suprascapular nerve in the spinoglenoid notch is a safe treatment for chronic osteoarthritic shoulder pain, with repeat treatments infrequently required. It is associated with significant improvement in VAS pain scores.

KEY POINTS

• Ultrasound-guided continuous radiofrequency lesioning of the suprascapular nerve in the spinoglenoid notch is a safe treatment for chronic shoulder pain in degenerative disease, with repeat treatments infrequently required. • The procedure is performed under ultrasound guidance, without the use of ionising radiation.

Anesthesia for the Patient Undergoing Shoulder Surgery

Shoulder surgery introduces important anesthesia considerations. The interscalene nerve block is considered the gold standard regional anesthetic technique and can serve as the primary anesthetic or can be used for postoperative analgesia. Phrenic nerve blockade is a limitation of the interscalene block and various phrenic-sparing strategies and techniques have been described. Patient positioning is another important anesthetic consideration and can be associated with significant hemodynamic effects and position-related injuries.

Ultrasound-Guided Treatments for the Painful Shoulder

Shoulder pain is an extremely common condition. The painful shoulder may be the result of a wide spectrum of underlying pathological conditions, including calcific tendinopathy of the rotator cuff, subacromial-subdeltoid bursitis, acromioclavicular or glenohumeral arthritis, tenosynovitis of the long biceps tendon, rotator cuff lesions, and many other less common conditions. Ultrasound imaging is an effective tool for the diagnosis and also for the image guidance of treatment of the majority of these conditions. Several ultrasound-guided procedures are effective for pain relief, such as percutaneous irrigation, intra-bursal or intra-articular drugs injection, fluid aspiration, neural block. This review article aims to summarize and discuss the most common treatment possibilities with ultrasound guidance for the painful shoulder.

A systematic review of the methods and drugs used for performing suprascapular nerve block injections for the non-surgical management of chronic shoulder pain

Suprascapular nerve block (SSNB) injections are growing in popularity as a treatment option for people with chronic shoulder pain. The optimal method of injection and aftercare is unknown. This review describes the current methods and drugs used for performing SSNB injections in the non-surgical management of adults with chronic shoulder pain in order to inform future research in this area. Systematic searches of CINAHL, MEDLINE (OVID), AMED, Embase databases and the Cochrane Library were undertaken from inception to June 2020. Data on the method and drugs used for injection and aftercare were extracted and summarised for areas of commonality and discrepancy. We included 53 studies in this review. In total, eight different injection methods were reported within the included studies. Indirect surface land-marked methods were the most common method reported in 21 studies. Direct surface land-marked methods were reported in 12 studies. Ultrasound-guided methods used alone were reported in 16 studies. Both fluoroscopy and computed tomography methods used alone were reported in one study each. Electromyography was used in combination with other injection methods in nine studies. Wide variation in the composition of the injectate was observed between studies. Local anaesthetic was used within injectate preparations in all studies. Local anaesthetic used alone was reported in 20 studies, combined with steroid in 29 studies and combined with various other components in 5 studies. Physiotherapy following injection was reported in 26 studies. Reported details of physiotherapy varied considerably. This review identified substantial variation in the methods and drugs used to perform SSNB injection in clinical trials. Current literature demonstrates a wide range of methods used for SSNB injection administration. Consensus research defining standardised practice for SSNB injection is now needed to guide future clinical practice and research.

Effectiveness of Suprascapular Nerve Block in the Treatment of Hemiplegic Shoulder Pain: A Systematic Review and Meta-Analysis

Purpose: We aimed to investigate the effectiveness of suprascapular nerve block (SSNB) in patients with hemiplegic shoulder pain (HSP).

Background: SSNB is widely used in various shoulder pains, but whether it is effective in HSP remains unknown.

Methods: PubMed, Cochrane Library, and Embase databases were searched to identify potential citations. Randomized controlled trials meeting the eligible criteria were included in our analysis. The primary endpoint was Visual Analog Scale (VAS) with a maximum value of 100 and a minimum value of 0. Secondary endpoints were passive range of motion (PROM) that pain starts, and the PROM mainly included abduction, flexion, and external rotation. In addition, the upper extremity Fugl-Meyer assessment (FMA) was also included in our secondary endpoints.

Results: Eight studies with 281 patients were included in our analysis. For VAS, there was no obvious difference between SSNB group and control group regardless of the follow-up period (<4 weeks or ≥4 weeks), which were −6.62 (−15.76, 2.53; p = 0.16) and 1.78 (−16.18, 19.74; p = 0.85). For shoulder function, the PROM of abduction, flexion, and external rotation was similar between groups. However, motor function indicator FMA is lower in SSNB control than that in control group, with a mean difference (and 95% CI) of −2.59 (−4.52, −0.66; p = 0.008).

Conclusion: SSNB is an effective way for HSP patients.

Systematic Review Registration: Registration ID: CRD42021252429.

Multimodal nerve injection provides noninferior analgesic efficacy compared with interscalene nerve block after arthroscopic rotator cuff repair

PURPOSE

This randomized noninferiority trial aimed to evaluate whether combined suprascapular, axillary nerve, and the articular branch of lateral pectoral nerve block (3NB) is noninferior to interscalene nerve block (ISB) for pain control after arthroscopic rotator cuff repair (ASRCR).

MATERIALS AND METHODS

Eighty-five patients undergoing ASRCR were randomized to either 3NB (n = 43) or ISB (n = 42) group. We used 5 and 15 ml of 0.2% ropivacaine for each nerve in the 3NB and ISB groups, respectively. The primary outcome was the visual analog scale (VAS) pain score at 4 h postoperatively measured assessed on an 11-point scale (ranging from 0 = no pain to 10 = worst pain) that was analyzed using noninferiority testing. The secondary outcome was VAS pain scores in the recovery room and at 8, 12, 24, 36, 48, and 72 h postoperatively. Rebound pain, IV-PCA usage during 48 h, dyspnea, muscle weakness, and satisfaction were evaluated.

RESULTS

Regarding the primary outcome, the mean difference in VAS pain scores between the 3NB (2.5 ± 1.6) and ISB (2.2 ± 2.3) groups at 4 h postoperatively was 0.3, with a 95% confidence interval (CI) of -0.56 to 1.11. The upper limit of 95% CI is lower than the noninferiority margin of 1.3 (p < 0.001). At all other time points, except in the recovery room, 3NB showed noninferior to ISB. Rebound pain, IV-PCA usage during the second 24 h, and muscle weakness were lower in the 3NB group (all p < 0.005). The satisfaction was similar in both groups (p = 0.815).

CONCLUSION

Combined 3NB is noninferior to ISB in terms of pain control after ASRCR; and is associated with low levels of rebound pain, IV-PCA usage, and muscle weakness.

LEVEL OF EVIDENCE

Randomized controlled trial, Level I.

Ultrasonography-Guided Common Musculoskeletal Interventions from Head to Toe: Procedural Tips for General Radiologists

The expanding scope of interventional musculoskeletal procedures has resulted in increased pressure on general radiologists. The confidence of general radiologists in performing ultrasound-guided musculoskeletal procedures varies with their clinical exposure. This didactic review provides a methodologically and clinically oriented approach to enhancing user understanding and confidence in performing ultrasound-guided musculoskeletal procedures. The body of the text is accompanied by figures depicting the procedural approach, injection site, and labeled ultrasonography images. This paper aims to provide a teaching and bedside aid for education on and the execution of musculoskeletal procedures to ensure the provision of quality health care.

Suprascapular nerve block is a clinically attractive alternative to interscalene nerve block during arthroscopic shoulder surgery: a meta-analysis of randomized controlled trials

BACKGROUND

The interscalene brachial plexus block (ISB) is a commonly used nerve block technique for postoperative analgesia in patients undergoing shoulder arthroscopy surgery; however, it is associated with potentially serious complications. The use of suprascapular nerve block (SSNB) has been described as an alternative strategy with fewer reported side effects for shoulder arthroscopy. This review aimed to compare the impact of SSNB and ISB during shoulder arthroscopy surgery.

METHODS

A meta-analysis was conducted to identify relevant randomized controlled trials involving SSNB and ISB during shoulder arthroscopy surgery. Web of Science, PubMed, Embase, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CNKI, and Wanfang database were searched from 2010 through March 2021.

RESULTS

We identified 1255 patients assessed in 17 randomized controlled trials. Compared with the ISB group, the SSNB group had higher VAS at rest in PACU (P = 0.003), 1 h after operation (P = 0.005), similar pain score 2 h (P = 0.39), 3-4 h (P = 0.32), 6-8 h after operation (P = 0.05), then lower VAS 12 h after operation (P = 0.00006), and again similar VAS 1 day (P = 0.62) and 2 days after operation (P = 0.70). As for the VAS with movement, the SSNB group had higher pain score in PACU (P = 0.03), similar VAS 4-6 h after operation (P = 0.25), then lower pain score 8-12 h after operation (P = 0.01) and again similar VAS 1 day after operation (P = 0.3) compared with the ISB group. No significant difference was found for oral morphine equivalents use at 24 h (P = 0.35), duration of PACU stay (P = 0.65), the rate of patient satisfaction (P = 0.14) as well as the rate of vomiting (P = 0.56), and local tenderness (P = 0.87). However, the SSNB group had lower rate of block-related complications such as Horner syndrome (P < 0.0001), numb (P = 0.002), dyspnea (P = 0.04), and hoarseness (P = 0.04).

CONCLUSION

Our high-level evidence established SSNB as an effective and safe analgesic technique and a clinically attractive alternative to interscalene block with the SSNB'S advantage of similar pain control, morphine use, and less nerve block-related complications during arthroscopic shoulder surgery, especially for severe chronic obstructive pulmonary disease, obstructive sleep apnea, and morbid obesity. Given our meta-analysis's relevant possible biases, we required more adequately powered and better-designed RCT studies with long-term follow-up to reach a firmer conclusion.

Diagnostic block and radiofrequency ablation of the acromial branches of the lateral pectoral and suprascapular nerves for shoulder pain: a 3D cadaveric study

BACKGROUND AND OBJECTIVES

Acromial branches of the lateral pectoral and suprascapular nerves have been proposed as targets for diagnostic block and radiofrequency ablation to treat superior shoulder pain; however, the nerve capture rates of these procedures have not been investigated. The objectives of this study were to use dissection and 3D modeling technology to determine the course of these acromial branches, relative to anatomical landmarks, and to evaluate nerve capture rates using ultrasound-guided dye injection and lesion simulation.

METHODS

Ultrasound-guided dye injections, targeting the superior surface of coracoid process and floor of supraspinous fossa, were performed (n=5). Furthermore, needles targeting the superior and posterior surfaces of the coracoid process were placed under ultrasound guidance to simulate needle electrode position (n=5). Specimens were dissected, digitized, and modeled to determine capture rates of acromial branches of lateral pectoral and suprascapular nerves.

RESULTS

The course of acromial branches of lateral pectoral and suprascapular nerves were documented. Dye spread capture rates: acromial branches of lateral pectoral and suprascapular nerves were captured in all specimens. Lesion simulation capture rates: (1) when targeting superior surface of coracoid process, the entire acromial branch of lateral pectoral nerve was captured in all specimens and (2) when targeting posterior surface of coracoid process, the acromioclavicular and bursal branches of acromial branch of suprascapular nerve were captured in all specimens; coracoclavicular branch was captured in 3/5 specimens.

CONCLUSIONS

This study supports the anatomical feasibility of ultrasound-guided targeting of the acromial branches of lateral pectoral and suprascapular nerves. Further clinical investigation is required.

A systematic review and meta-analysis of radiofrequency procedures on innervation to the shoulder joint for relieving chronic pain

BACKGROUND AND OBJECTIVE

Studies have reported relief of chronic shoulder pain with non-ablative pulsed neuromodulatory (pRF) or ablative radiofrequency (aRF) procedures on innervation of the shoulder joint but interpretation of these reports is hampered by inconsistent indications, anatomic targets and follow-up. This systematic review was conducted to synthesize the existing literature on procedures employing pRF or aRF for treating chronic shoulder pain.

DATABASES AND DATA TREATMENT

MEDLINE and other medical literature databases were reviewed up to 31 December 2019 for publications on pRF or aRF procedures on shoulder joint innervation to relieve chronic pain. Data on analgesic and functional outcomes measured at any time point following the interventions were extracted. Existing knowledge on innervation of the shoulder joint with relevance to RF procedures was also synthesized.

RESULTS

In all, 42 publications, 7 randomized controlled trials (RCTs) and 35 observational studies, case series or reports were identified. Thirty-six of these publications were on pRF procedure and 29 of these reported procedures exclusively targeting the suprascapular nerve. A meta-analysis of the seven RCTs evaluating pRF indicated no analgesic benefit or functional improvement with this treatment over conventional medical management. Case series and reports on aRF indicate a potential for analgesic benefit but the quality of this evidence was low.

CONCLUSIONS

RF treatments targeting the sensory innervation of the shoulder joint affected by degenerative conditions have the potential to reduce pain but the current evidence does not suggest analgesic or functional benefit (GRADE certainty of evidence-low). Studies of high methodological quality are required to further investigate the role of these interventions.

SIGNIFICANCE

This is a comprehensive review of literature on pulsed (non-ablative) and ablative radiofrequency (RF) procedures for chronic shoulder pain. The systematic review and meta-analysis of 7 trials found that pulsed RF for chronic shoulder pain provided similar analgesia and functional improvement as conservative medical management at three months after the procedures. The case series and reports on ablative RF for shoulder pain indicate possible analgesic benefit but their quality was low. This review highlights the need for studies of a high quality on ablative RF treatments for chronic shoulder pain.

Proximal vs Distal Approach of Ultrasound-guided Suprascapular Nerve Block for Patients With Adhesive Capsulitis of the Shoulder: Prospective Randomized Controlled Trial

OBJECTIVES

To evaluate the early clinical outcomes of ultrasound (US)-guided suprascapular nerve block (SSNB) using a proximal approach compared with a distal approach for outpatient treatment of adhesive capsulitis.

DESIGN

Randomized controlled trial.

SETTING

Outpatient clinic PARTICIPANTS: Participants (N=47) with symptomatic adhesive capsulitis.

INTERVENTIONS

Participants were randomly assigned to either US-guided SSNB using a proximal approach (n=23, proximal group) or a distal approach (n=24, distal group).

MAIN OUTCOME MEASURES

The primary outcome measure was the visual analog scale (VAS) for pain at week 12. Secondary outcomes included the American Shoulder Elbow Surgeon's (ASES) score, University California Los Angeles score, Short Form-36 mental and physical component summaries, and range of motion. All patients completed clinical follow-up at 2, 6, and 12 weeks after treatment. On US images, depth and insertion angle of needle during injection were measured.

RESULTS

The VAS significantly improved in both groups at week 12. After treatment, no significant differences were found in early clinical outcomes (weeks 2, 6, and 12) between groups (all P>.05), except that ASES at 2 weeks showed a significantly higher score in the distal group than in the proximal group (87.1±4.8 and 83.0±6.3, respectively; P=.014). The mean depth and insertion angle of needle was significantly lower (depth: 13.4±3.9 and 30.6±4.3 mm, respectively; P<.001; insertion angle: 19.6°±6.4° and 38.7°±5.8°; P<.001) in the proximal group than in the distal group.

CONCLUSIONS

This study demonstrated that proximal approach of US-guided SSNB provided favorable short-term outcomes of pain and functional improvement and that outcomes were comparable to those of the distal approach in adhesive capsulitis. The suprascapular nerve was located more superficially and easily identified in the proximal approach, suggesting that this method might improve the accuracy of injection.

Ultrasound-Guided Interscalene Brachial Plexus Block for Pathological Humerus Fracture due to Multiple Myeloma with Systemic Manifestation: Useful Option for Management in Low-Income Countries

Anesthetic management of pathological fracture due to multiple myeloma with systemic manifestation poses a perioperative challenge especially in low-resource setups like Nepal. Regional anesthesia using ultrasound-guided block can improve the accuracy, reduce complications, and improve overall perioperative management of pathological fractures due to malignancy with systemic spread in resource-deprived setups. We present a case of a 53-year-old lady with pathological fracture of left humerus shaft, a diagnosed case of multiple myeloma with compression fracture of multiple lumbar spine with chest wall metastasis with resolving acute kidney injury with chest infections. Ultrasound-guided interscalene brachial plexus block with sedation was done for open reduction internal fixation of humerus shaft fracture taking in consideration the overall high perioperative risk of patient. Intraoperative hemodynamic was uneventful, with no neurological sequelae and good recovery status perioperatively. Ultrasound-guided interscalene brachial plexus block if done cautiously can be a very useful alternative technique for better perioperative outcome in patients with malignancy with systemic spread in areas where expertise is scarce and resource is limited.

Ultrasound-guided pulsed radiofrequency treatment for distal suprascapular neuropathy: A case report

RATIONALE

Suprascapular neuropathy is a rare cause of shoulder pain, and patients usually presents with posterosuperior shoulder pain and weakness on forward flexion and external rotation. Suprascapular neuropathy associated with rotator cuff pathology has received attention as an emerging cause of this condition. Suprascapular nerve (SSN) block can be used in these patients, and pulsed radio frequency (PRF) can be applied to achieve a long-term effect. Several studies have reported on PRF treatment of the SSN for shoulder pain, but most applied treatment to the nerve trunk under the transverse scapular ligament. This report describes a patient with suprascapular neuropathy treated with selective application of PRF to the distal SSN under ultrasound guidance.

PATIENT CONCERNS

A 68-year-old woman suffered from right posterior shoulder pain after traumatic full thickness rotator cuff tear. Her pain was not diminished despite of 2 surgeries.

DIAGNOSES

She was diagnosed with entrapment of the distal SSN in the spino-glenoid (SGN) notch and suprascapular neuropathy.

INTERVENTIONS

She underwent surgery to decompress the entrapped SSN in the SGN. After that, we applied PRF on the distal SSN under ultrasound guidance for persistent pain. This treatment was repeated 3 times.

OUTCOMES

PRF treatment resulted in a slight reduction in the visual analogue scale (VAS) pain score from 7-8/10 to 5-6/10 at the 2 weeks follow-up, and to 2-3/10 at the 1 month follow-up. The reduction in pain was maintained at the 1 year follow-up.

LESSONS

PRF treatment of the SSN is typically approached from the main branch in the suprascapular notch. We selectively applied PRF to the distal SSN close to the SGN. This technique was safe and effective.

A case series of suprascapular nerve block (with an historical comparator) for shoulder pain in motor neurone disease

BACKGROUND

Shoulder pain is a distressing but under-reported and poorly managed symptom in people with motor neurone disease.

OBJECTIVES

This study aimed to assess the efficacy of suprascapular nerve block for the management of shoulder pain in patients with motor neurone disease.

METHODS

A total of 27 patients with motor neurone disease and shoulder pain were offered a suprascapular nerve block. Ten of these patients had bilateral shoulder pain and both were injected, making a total of 37 shoulders. The patients were followed up for a total of 3 months, or until death. Shoulder pain was measured using the pain scale (out of 100) of the shoulder pain and disability index and compared with baseline scores and a placebo control group from an earlier study using the same methodology (ACTRN12619000353190).

RESULTS

Following the nerve block there was a significant improvement of pain scores from baseline (58.4) at week 1 (20.8, p < 0.000), week 6 (17.6, p < 0.000) and week 12 (30.4, p = 0.001) and a significant improvement compared with the control group across each time interval.

CONCLUSION

Suprascapular nerve block is a safe, effective therapy for patients with chronic shoulder pain.

Effectiveness of new nerve blocks method on the articular branches of the suprascapular and subscapular nerves to treat shoulder pain

To evaluate the effectiveness and safety of performing nerve blocks on the articular branches of the suprascapular and subscapular nerves for the treatment of shoulder pain caused by various pathologies.Fifty-two patients with shoulder pain were included in this study. Suprascapular and subscapular nerve blocks were performed with 2.5 mL anesthetic solution (2 mL of 0.5% bupivacaine and 0.5 mL of 2 mg/mL dexamethasone). The subjects were evaluated before the procedure and 1, 3, and 6 months afterward by means of the numeric rating scale and the shoulder pain and disability index. A post-injection pain reduction of >50% and <50% was considered a positive and negative response to the blocks, respectively.After nerve blocks, the mean numeric rating scale and shoulder pain and disability index scores were significantly reduced from pre-injection values, and this effect persisted for 6 months after injection. The positive and negative response groups consisted of 31 (60%) and 21 (40%) patients, respectively. The positive response group showed significantly better outcomes on the numeric rating scale and shoulder pain and disability index compared with the negative response group. No patients reported adverse effects either during or after the procedure.Performing nerve blocks on the articular branches of the suprascapular and subscapular nerves resulted in positive outcomes for shoulder pain patients. Regardless of shoulder pathology, this new injection method can be safely used in shoulder pain patients.

Determining anatomic accuracy of shoulder field injection: triangular injection technique does adequately reach pain transmitters

Background

Controlling pain after shoulder surgery is a critical component of postsurgical care. Several recent studies have described the use of periarticular, local infiltration anesthesia, and field blocks (FBs) with clinical efficacy after shoulder surgery. The anatomic accuracy and safety of these FBs have not been well described. The purpose of this study was to determine the accuracy of a surgeon performed shoulder field injection. We hypothesized that our field injection would adequately reach the pain transmitters responsible for postsurgical shoulder pain.

Methods

A total of 10 cadaveric specimens were used in the study. A mixture of liposomal bupivacaine, normal saline, and methylene blue totaling 60 cc was prepared. After injection, the specimens were left for 4 hours to allow medication diffusion. The dissection of specimens was performed to identify 4 areas: axillary nerve, suprascapular nerve, supraclavicular nerves, and joint capsule. On dissection, accuracy rates were determined for each area.

Results

All 10 cadaveric specimens were injected and dissected to completion. The dissection of the axillary nerve showed methylene blue dye surrounding the nerve in 10 of 10 (100%) specimens, the suprascapular nerve in 9 of 10 (90%), and the supraclavicular nerves in 10 of 10 (100%). Zero of 10 (0%) specimens had any dye penetrate into the glenohumeral joint or capsule.

Conclusion

The accuracy rates of the injection of the mixture into the shoulder specimens suggest potential to reproduce an FB to the tissues that are responsible for postoperative pain after shoulder surgery. This may represent an option when interscalene nerve block is not desired or contraindicated.

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

[Efficacy of ultrasound guided suprascapular block in patients with chronic shoulder pain: retrospective observational study]

INTRODUCTION

Painful shoulder syndrome is a frequent condition among the elderly and an important cause of functional disability. As the conservative is not always effective, ultrasound guided suprascapular nerve blockade presents as an important alternative treatment.

OBJECTIVE

To evaluate the efficacy and safety of the use of 0.25% levobupivacaine and 40 mg of triamcinolone in the suprascapular nerve blockade in patients with chronic pain in the shoulder.

METHODS

A retrospective, descriptive and analytical study of 71 patients submitted to suprascapular nerve infiltration between August 2014 and March 2017. Surveys were carried out to patients before the technique was performed, after 72 hours, at 1, 3 and 6 months. Pain intensity was assessed using a numeric pain scale (NPS).

RESULTS

Out of the 71 patients who underwent a blockade of the suprascapular nerve, 81.2% reported a decrease in pain at 72 hours. In the first, third and sixth month, respectively, 89.8%, 76.1% and 61.8% of the patients presented pain relief. A statistically significant difference (p<0.001) was verified between NPS and the 4 moments assessed after the technique. 43.7% had total pain remission (NPS=0) at six months. Global effectiveness of suprascapular nerve blockade was 60.6% and for the subgroup of patients with rotators' cuff patology was 62.2%. No complications were reported regarding the suprascapular nerve block.

CONCLUSION

The results show that ultrasound-guided blockade of the suprascapular nerve using 0.25% levobupivacaine and 40 mg of triamcinolone is a safe and effective treatment in patients with chronic shoulder pain.

[Efficacy of ultrasound guided suprascapular block in patients with chronic shoulder pain: retrospective observational study]

INTRODUCTION

Painful shoulder syndrome is a frequent condition among the elderly and an important cause of functional disability. As the conservative treatment is not always effective, ultrasound guided suprascapular nerve blockade presents as an important alternative treatment.

OBJECTIVE

To evaluate the efficacy and safety of the use of 0.25% levobupivacaine and 40 mg of triamcinolone in the suprascapular nerve blockade in patients with chronic pain in the shoulder.

METHODS

A retrospective, descriptive and analytical study of 71 patients submitted to suprascapular nerve infiltration between August 2014 and March 2017. Surveys were carried out to patients before the technique was performed, after 72 hours and at 1, 3 and 6 months. Pain intensity was assessed using a numeric pain scale (NPS).

RESULTS

Out of the 71 patients who underwent a blockade of the suprascapular nerve, 81.2% reported a decrease in pain at 72 hours. In the first, third and sixth month, respectively, 89.8%, 76.1% and 61.8% of the patients presented pain relief. A statistically significant difference (p < 0.001) was verified between NPS and the 4 moments assessed after the technique. 43.7% had total pain remission (NPS = 0) at six months. Global effectiveness of suprascapular nerve blockade was 60.6% and for the subgroup of patients with rotators’ cuff patology was 62.2%. No complications were reported regarding the suprascapular nerve block.

CONCLUSION

The results show that ultrasound-guided blockade of the suprascapular nerve using 0.25% levobupivacaine and 40 mg of triamcinolone is a safe and effective treatment in patients with chronic shoulder pain.

Continuous suprascapular nerve block compared with single-shot interscalene brachial plexus block for pain control after arthroscopic rotator cuff repair

OBJECTIVES

We compared the analgesic efficacy of a continuous suprascapular nerve block (C-SSNB) and a single-shot interscalene brachial plexus block (S-ISNB) for postoperative pain management in patients undergoing arthroscopic rotator cuff repair.

METHODS

A total of 118 patients undergoing arthroscopic rotator cuff repair were randomly allocated to the S-ISNB or C-SSNB groups. Postoperative pain was assessed using the visual analog scale (VAS) at 1, 2, 6, 12, and 24 h postoperatively. Supplemental analgesic use was recorded as total equianalgesic fentanyl consumption.

RESULTS

The C-SSNB group showed significantly higher VAS scores at 0-1 h and 1-2 h after the surgery than the S-ISNB group (4.9±2.2 versus 2.3±2.2; p<0.0001 and 4.8±2.1 versus 2.4±2.3; p<0.0001, respectively). The C-SSNB group showed significantly lower VAS scores at 6-12 h after the surgery than the S-ISNB group (4.1±1.8 versus. 5.0±2.5; p=0.031). The C-SSNB group required significantly higher doses of total equianalgesic fentanyl in the post-anesthesia care unit than the S-ISNB group (53.66±44.95 versus 5.93±18.25; p<0.0001). Total equianalgesic fentanyl in the ward and total equianalgesic fentanyl throughout the hospital period were similar between the groups (145.99±152.60 versus 206.13±178.79; p=0.052 and 199.72±165.50 versus 212.15±180.09; p=0.697, respectively).

CONCLUSION

C-SSNB was more effective than S-ISNB at 6-12 h after the surgery for postoperative analgesia after arthroscopic rotator cuff repair.

Analgesic benefits and clinical role of the posterior suprascapular nerve block in shoulder surgery: a systematic review, meta-analysis and trial sequential analysis

The posterior suprascapular nerve block has been proposed as an analgesic alternative for shoulder surgery based on the publication of several comparisons with interscalene block that failed to detect differences in analgesic outcomes. However, quantification of the absolute treatment effect of suprascapular nerve block on its own, in comparison with no block (control), to corroborate the aforementioned conclusions has been lacking. This study examines the absolute analgesic efficacy of suprascapular nerve block compared with control for shoulder surgery. We systematically sought electronic databases for studies comparing suprascapular nerve block with control. The primary outcomes included postoperative 24-h cumulative oral morphine consumption and the difference in area under the curve for 24-h pooled pain scores. Secondary outcomes included the incidence of opioid-related side-effects (postoperative nausea and vomiting) and patient satisfaction. Data were pooled using random-effects modelling. Ten studies (700 patients) were analysed; all studies examined landmark-guided posterior suprascapular nerve block performed in the suprascapular fossa. Suprascapular nerve block was statistically but not clinically superior to control for postoperative 24-h cumulative oral morphine consumption, with a weighted mean difference (99%CI) of 11.41 mg (-21.28 to -1.54; p = 0.003). Suprascapular nerve block was also statistically but not clinically superior to control for area under the curve of pain scores, with a mean difference of 1.01 cm.h. Nonetheless, suprascapular nerve block reduced the odds of postoperative nausea and vomiting and improved patient satisfaction. This review suggests that the landmark-guided posterior suprascapular nerve block does not provide clinically important analgesic benefits for shoulder surgery. Investigation of other interscalene block alternatives is warranted.

Diaphragm-sparing nerve blocks for shoulder surgery, revisited

Although interscalene brachial plexus block (ISB) remains the gold standard for analgesia after shoulder surgery, the inherent risks of ipsilateral phrenic nerve block and hemidiaphragmatic paralysis (HDP) limit its use in patients with preexisting pulmonary compromise. In a previous Daring Discourse (2017), our research team has identified potential diaphragm-sparing alternatives to ISB for patients undergoing shoulder surgery. In recent years, the field has been fertile with research, with the publication of multiple randomized controlled trials investigating supraclavicular blocks, upper trunk blocks, anterior suprascapular nerve blocks, costoclavicular blocks, and combined infraclavicular-suprascapular blocks. To date, the cumulative evidence (pre-2017 and post-2017) suggests that costoclavicular blocks may provide similar postoperative analgesia to ISB coupled with a 0%-incidence of HDP. However, in light of the small number of patients recruited by the single study investigating costoclavicular blocks, further confirmatory trials are required. Moreover, future investigation should also be undertaken to determine if costoclavicular blocks could achieve surgical anesthesia for shoulder surgery. Anterior suprascapular nerve blocks have been demonstrated to provide surgical anesthesia and similar analgesia to ISB. However, their risk of HDP has not been formally quantified. Of the remaining diaphragm-sparing nerve blocks, supraclavicular blocks (with local anesthetic injection posterolateral to the brachial plexus), upper trunk blocks, and combined infraclavicular-anterior suprascapular blocks merit further investigation, as they have been shown to achieve similar analgesia to ISB, coupled with an HDP incidence <10%.

Superior Trunk Block

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Interscalene nerve blockade remains one of the most commonly used anesthetic and analgesic approaches for shoulder surgery. The high incidence of hemidiaphragmatic paralysis associated with the block, however, precludes its use among patients with compromised pulmonary function. To address this issue, recent studies have investigated phrenic-sparing alternatives that provide analgesia. None, however, have been able to reliably demonstrate surgical anesthesia without significant risk for hemidiaphragmatic paralysis. The utility of the superior trunk block has yet to be studied. The hypothesis was that compared with the interscalene block, the superior trunk block will provide noninferior surgical anesthesia and analgesia while sparing the phrenic nerve.

Methods

This randomized controlled trial included 126 patients undergoing arthroscopic ambulatory shoulder surgery. Patients either received a superior trunk block (n = 63) or an interscalene block (n = 63). The primary outcomes were the incidence of hemidiaphragmatic paralysis and worst pain score in the recovery room. Ultrasound was used to assess for hemidiaphragmatic paralysis. Secondary outcomes included noninvasively measured parameters of respiratory function, opioid consumption, handgrip strength, adverse effects, and patient satisfaction.

Results

The superior trunk group had a significantly lower incidence of hemidiaphragmatic paralysis compared with the interscalene group (3 of 62 [4.8%] vs. 45 of 63 [71.4%]; P &lt; 0.001, adjusted odds ratio 0.02 [95% CI, 0.01, 0.07]), whereas the worst pain scores in the recovery room were noninferior (0 [0, 2] vs. 0 [0, 3]; P = 0.951). The superior trunk group were more satisfied, had unaffected respiratory parameters, and had a lower incidence of hoarseness. No difference in handgrip strength or opioid consumption were detected. Superior trunk block was associated with lower worst pain scores on postoperative day 1.

Conclusions

Compared with the interscalene block, the superior trunk block provides noninferior surgical anesthesia while preserving diaphragmatic function. The superior trunk block may therefore be considered an alternative to traditional interscalene block for shoulder surgery.

Ultrasound-Guided Versus Landmark-Based Approach to the Distal Suprascapular Nerve Block: A Comparative Cadaveric Study

PURPOSE

To compare the accuracy of distal suprascapular nerve (dSSN) blockade performed with the use of ultrasound-guided regional anesthesia (USRA) versus with a landmark-based approach (LBA). A secondary aim was to describe the anatomic features of the sensory branches of the dSSN.

METHODS

USRA and LBA were performed in 15 shoulders each from 15 cadavers (total of 30 shoulders). Then, 10 mL of methylene blue‒infused ropivacaine 0.75% was injected into the dSSN. Simultaneously, 2.5 mL of red latex solution was injected to identify the position of the needle tip. The division and distribution of the sensory branches originating from the SSN were described.

RESULTS

The tip of the needle was identified at 1.3 cm (range, 0-5.2 cm) and 1.5 cm (range, 0-4.5 cm) with USRA and the LBA, respectively (P = .90). Staining diffused past the origin of the most proximal sensory branch in 27 cases. The most proximal sensory branch arose 2.5 cm from the suprascapular notch. Among the 3 failures that occurred in the USRA group, the sensory branches also failed to be marked. All 30 dSSNs gave off 3 sensory branches, which innervated the posterior glenohumeral capsule, the subacromial bursa, and the coracoclavicular and acromioclavicular ligaments.

CONCLUSIONS

An LBA is as reliable and accurate as US guidance for anesthetic blockade of the dSSN. Marking of the suprascapular nerve must be proximal to the suprascapular notch to involve the 3 sensory branches in the anesthetic blockade.

CLINICAL RELEVANCE

The present study demonstrates that a landmark-based approach to anesthetic blockade of the distal suprascapular nerve is accurate and can be performed by orthopaedic surgeons lacking experience in ultrasound-guided anesthetic techniques.

Ultrasound-Guided Proximal and Distal Suprascapular Nerve Blocks: A Comparative Cadaveric Study

Objectives

The primary aim of our study was to evaluate and compare the accuracy of ultrasound (US)-guided distal suprascapular nerve (dSSN) and proximal SSN (pSSN) blocks. Secondary aims were to compare the phrenic nerve involvement between groups and to describe the anatomical features of the sensory branches of the dSSN.

Methods

pSSN and dSSN blocks were performed in 14 cadavers (28 shoulders). Ten mL of 0.2% ropivacaine colored with methylene blue was injected under US guidance. Accuracy was determined using SSN staining and the distance between predefined anatomical landmarks and the targeted SSN. The phrenic nerve (PN) was judged to be colored or not. The distribution of the sensory branches that originate from the 14 dSSNs is described. Quantitative data are expressed as median (range).

Results

The pSSN was dyed more frequently than the dSSN (13 vs 11, P = 0.59). The targeted SSN was close to the suprascapular notch (1.3 [0–5.2] cm) and the origin of the SSN (1.4 [0.2–4.5] cm) for dSSN and pSSN blocks, respectively (P = 0.62). For dSSN blocks, the most frequent injection site was the supraspinous fossa. Three PNs were marked in pSSN blocks, compared with none in dSSN blocks (P = 0.22). Three sensory branches were identified for all 14 dSSNs: the medial subacromial branch, the lateral subacromial branch, and the posterior glenohumeral branch.

Conclusions

US-guided pSSN and dSSN blocks can be realized with accuracy. A distal approach to the SSN could be an alternative to interscalene brachial plexus block for the management of postoperative pain after shoulder surgery in high–respiratory risk patients.

Quantitative analysis of the distal, lateral, and posterior articular branches of the axillary nerve to the shoulder: implications for intervention

INTRODUCTION

The terminal sensory branches innervating the shoulder joint are potential therapeutic targets for the treatment of shoulder pain. This cadaveric study investigated in detail the anatomic pathway of the posterior terminal sensory branch of the axillary nerve (AN) and its relationship to nearby anatomic structures for applications, such as nerve block or ablation of the shoulder joint.

METHODS

For this study, nine shoulders were dissected. Following dissection, methylene blue was used to stain the pathway of the terminal sensory branches of the AN to provide a visual relationship to the nearby bony structures. A transparent grid was overlaid on the humeral head to provide further detailed information regarding the innervation to the shoulder joint.

RESULTS

Eight of the nine shoulders displayed terminal sensory branches of the AN. The terminal sensory branches of the AN innervated the posterolateral head of the humerus and shoulder capsule and were deep and distal to the motor branches innervating the deltoid muscle and teres minor muscle. All terminal branches dissected innervated the shoulder capsule at the posteroinferior-lateral aspect of the greater tuberosity of the humerus. All specimens displayed innervation to the shoulder joint in the lateral most 25% and inferior most 37.5% before methylene blue staining.

CONCLUSION

The terminal sensory branches of the AN consistently innervate the inferior and lateral aspects of the posterior humeral head and shoulder capsule. These nerves are easily accessible and would provide a practical target for nerve block or ablation to relieve shoulder pain without compromising motor integrity.