Comparative study of anatomical landmark-guided versus ultrasound-guided suprascapular nerve block in chronic shoulder pain

Does a Suprascapular Nerve block reduce chronic shoulder pain at 3 months compared to standard non-operative care? A systematic review

PURPOSE

Chronic shoulder pain affects 2.4-30% of adults at any given time because of a wide variety of underlying pathologies. Treatment of chronic shoulder pain should attempt to address the underlying cause, if possible, either through surgical or non-surgical means. Routine non-operative care involves analgesia, physiotherapy and perhaps injection of corticosteroid at the appropriate site. A suprascapular nerve block (SSNB) is a minimally invasive, low-risk procedure which offers analgesia for patients. This review evaluates the effectiveness of SSNB in reducing shoulder pain at a 3-month follow-up, in comparison to standard non-operative care.

METHODS

A literature search was conducted across Medline, Embase, Cochrane, ISRCTN and clinicaltrial.gov databases from inception to November 2024. Ninety publications were screened by abstract followed by full text, by the authors against inclusion criteria, and risk of bias was assessed using the RoB 2 tool.

RESULTS

Five randomised studies were included for analysis, presenting a heterogeneous mix of intervention, study populations and outcome measures. The two studies performing SSNB with local anaesthetic (LA) and corticosteroid found a significant reduction in pain at 3 months. In contrast, compared to studies using LA alone did not demonstrate the same level of efficacy.

CONCLUSION

Suprascapular nerve block is an effective analgesic option for chronic shoulder pain, which can be offered to patients as part of a shared decision-making approach. While studies suggest efficacy of combined LA and corticosteroid, limitations such as heterogeneity, variability in result reporting and short follow-up periods reduce the strength of the evidence.

Adhesive capsulitis: current concepts

Adhesive capsulitis, commonly known as frozen shoulder, is a condition characterized by pain and progressive loss of shoulder motion. This condition typically affects individuals between 40 and 60 years of age and can severely impact daily functioning and quality of life. The etiology of adhesive capsulitis is multifactorial, with contributions from systemic conditions such as diabetes and thyroid disorders, as well as idiopathic factors. This review provides an overview of current concepts in the diagnosis and management of adhesive capsulitis, highlighting advancements in both conservative and surgical treatments. Conservative management remains the first-line approach, emphasizing pain relief and restoration of shoulder mobility through physical therapy, analgesics, and corticosteroid injections. Techniques such as the suprascapular nerve block have gained prominence for their effectiveness in reducing pain and facilitating rehabilitation. Recent studies underscore the importance of early intervention and individualized treatment plans tailored to the patient's needs. Surgical intervention, including arthroscopic capsular release, is considered when conservative measures fail to yield satisfactory results. While effective in restoring shoulder function, surgery carries risks and necessitates a comprehensive rehabilitation program to prevent recurrence of stiffness. This review also addresses potential complications associated with both conservative and surgical treatments, and the role of emerging techniques and technologies in improving patient outcomes. The integration of evidence-based practices and personalized care strategies is crucial for optimizing treatment efficacy and enhancing the quality of life for individuals affected by adhesive capsulitis.

Efficacy of Ultrasound-Guided Injections in Patients Unable to Access or Benefit From Physical Therapy: A Comparative Study of Subacromial Corticosteroid Injection, Suprascapular Nerve Block, and Their Combination in Shoulder Impingement Syndrome

Background This study aims to compare the efficacy of ultrasound (US)-guided subacromial bursa steroid injection (SABSI), suprascapular nerve block (SSNB), and combined injection therapy (SABSI + SSNB) on pain and shoulder function in patients with subacromial impingement syndrome who either did not respond to physical medicine and rehabilitation (PM&R) or reported being unable to attend the PM&R unit regularly. Methodology In this prospective, comparative cohort study, patients were randomly assigned using the envelope method to ensure an unbiased distribution. In total, 95 patients with subacromial impingement syndrome were divided into three groups according to the injection technique applied. All injections were applied to Group 1 (SABSI), Group 2 (SSNB), and Group 3 (SABSI + SSNB) under US guidance. Pain and shoulder function levels of the groups before and after treatment at one month and three months were evaluated using the Visual Analog Scale (VAS) and the Disabilities of the Arm, Shoulder and Hand (DASH) scale, respectively. For statistical analysis, the Shapiro-Wilk test was used to assess the normality of continuous data. One-way analysis of variance with Bonferroni correction was applied for normally distributed variables, while the Kruskal-Wallis test was used for non-normally distributed data. Pearson's chi-square test was performed to compare categorical variables. Results Between pre-treatment and one month post-treatment, there were statistically significant differences in the percentage change of VAS rest, VAS activity, and DASH scores among the groups (p = 0.004, <0.001, and <0.001, respectively). These significant differences persisted over the period from pre-treatment to three months post-treatment, with all p-values being ≤0.002. Throughout both assessment intervals, Groups 1 and 2 displayed statistically similar percentage changes across all parameters; however, these changes were significantly lower than those observed in Group 3. Patients unable to attend PM&R units displayed a longer symptom duration compared to patients who were non-responders to PM&R (p = 0.015). The distribution of these three injection techniques across the two groups was similar (p = 0.831), and both groups showed similar responses to US-guided injections in terms of pain and functionality (all p > 0.05). Conclusions US-guided SABSI combined with SSNB in patients with shoulder impingement was found to be superior compared to their sole applications in terms of improvement in shoulder pain and function. These findings suggest that the combined approach is a promising alternative for managing shoulder impingement syndrome, particularly in patients facing barriers to PM&R access.

Assessing the effectiveness of suprascapular nerve block in the treatment of frozen shoulder

Aims

Frozen shoulder is a common and debilitating condition characterized by pain and restricted movement at the glenohumeral joint. Various treatment methods have been explored to alleviate symptoms, with suprascapular nerve block (SSNB) emerging as a promising intervention. This meta-analysis aimed to assess the effectiveness of SSNB in treating frozen shoulder.

Methods

The study protocol was registered with PROSPERO (CRD42023475851). We searched the MEDLINE, Embase, and Cochrane Library databases in November 2023. Randomized controlled trials (RCTs) comparing SSNB against other interventions were included. The primary outcome was any functional patient-reported outcome measure. Secondary outcomes were the visual analogue scale (VAS) for pain, range of motion (ROM), and complications. Risk of bias was assessed using the Cochrane risk of bias v. 2.0 tool.

Results

A total of 12 RCTs were identified (702 patients; mean age 55 years (30 to 72)). Eight RCTs were deemed "low" risk-of-bias and four raised "some concerns". Comparator interventions included intra-articular steroid injection (IAI), hydrodistension, physiotherapy, and placebo injection with 0.9% saline. Seven studies compared SSNB to IAI, with SSNB resulting in greater improvement in the Shoulder and Pain Disability Index (mean difference -4.75 (95% CI -8.11 to -1.39); p = 0.006) and external rotation (mean difference 11.64 (95% CI -0.05 to 23.33); p = 0.050). In three studies, SSNB demonstrated better VAS (mean difference -0.31 (95% CI -0.53 to 1.79); p = 0.004) compared to physiotherapy (with or without placebo injection). One study favoured hydrodistension over SSNB in improving ROM and VAS. There was no significant difference in outcomes between SSNB administered under ultrasound guidance or using a landmark technique.

Conclusion

SSNB can be administered in the outpatient clinic with promising outcomes compared to IAI or physiotherapy based on level I evidence. It can therefore be considered as a first-line treatment option.

Variability in the distance between the suprascapular notch with the spine of the scapulae and the acromion

INTRODUCTION

The suprascapular notch lies in the superior border of the scapula and is a passageway for the suprascapular nerve that is sensory to the shoulder joint. Suprascapular nerve block involves injection of local anaesthetic into the suprascapular notch, either ultrasound guided or blind, using the spine of scapula and/or the medial border of the acromion as surface landmarks.

AIM

To investigate the anatomic variations that exist between the distance of the notch from the spine of scapula and acromion.

METHOD

Ninety-two dry scapulae were measured with a digital calliper for their length of the spine, distance between the midpoint of the spine and base of the suprascapular notch and distance between the medial border of the acromion and the base of the suprascapular notch. These measurements were compared for variations in the scapular bony landmarks, the spine and the acromion to determine the site for the injection.

RESULTS

Measurement reliability was assessed by intraclass correlation, Cronbach's alpha being 0.99, 0.97 and 0.91 for length of spine, distance from spine and distance from acromion respectively. The distance from the acromion had less variation in measurement (3.73 ± 0.42 cm) but a flatter distribution when compared to distance from the spine of the scapula (3.32 ± 0.39 cm).

CONCLUSION

Length of the spine of the scapula appeared not to influence either distance from the acromion or distance from the spine of scapula. There is potential for greater variability in placement of nerve blocks that use acromion as the bony reference. Key Points • Dry scapular measurement using electronic Vernier callipers is accurate (0.91-0.97). • There is potential for greater variability in placement of blind nerve blocks that use acromion as the bony reference to locate the suprascapular notch.

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.

Adhesive Capsulitis' Patients Report Improvement in Functionality Trough International Classification of Functioning, Disability and Health Checklist and Dash After Suprascapular Nerve Blocks

Objective  To evaluate the functionality in patients with adhesive capsulitis undergoing suprascapular nerve block (SSNB). Methods  A before-and-after clinical prospective study in a single center was conducted with patients with secondary adhesive capsulitis treated with four nerve blocks based on anatomical limits. The sample was non-probabilistic, and it was obtained after a routine appointment at a specialized outpatient clinic. The instruments used for evaluation were the International Classification of Functioning, Disability and Health (ICF) and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, which were applied at baseline (T 0 ), one week after the fourth SSNB (T 4 ), and three months after the first SSNB (T 12 ). The paired t -test was used to compare the means of the ICF checklist items and DASH in the different: T 0 xT 4 ; T 4 xT 12 ; and T 0 xT 12 ). The probability of rejecting the null hypothesis was 5%. Results  The sample was composed of 25 individuals with a mean age of 58.16 years; 16 of them were female. The duration of the pain symptoms ranged from 2 to 16 months, with a mean of 5.92 months. The ICF checklist showed that all domains had already improved in T 4, except for the environmental factors, which only improved at 03 months ( p  = 0.037). The patients reported improvements in shoulder function in T 4 , which increased more in T 12 , at the end of data collection ( p  = 0.019). Conclusion  The SSNB technique is effective in patients with adhesive capsulitis after 4 weeks of application, with improvements in individual's functionality lasting for 12 weeks.

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.

Ultrasound Guidance Is Not Superior in Subacromial Bursa and Intraarticular Injections but Superior in Bicipital Groove: A Meta-analysis of Randomized Controlled Trials

PURPOSE

To perform a meta-analysis comparing the clinical and functional outcomes of ultrasound-guided (USG) and blind injections for shoulder pain.

METHOD

The Embase, Cochrane Library, and PubMed databases were searched from database inception to April 7, 2021. Clinical and functional outcomes included the visual analog scale (VAS) pain score, abduction, flexion, American Shoulder and Elbow Surgeons Assessment Form (ASES) score, Constant-Murley Shoulder (CMS) score, Shoulder Pain and Disability Index (SPADI), Shoulder Disability Questionnaire (SDQ) score, and Shorted Disabilities of the Arm, Shoulder and Hand (Quick DASH) score. Dichotomous outcomes were assessed with mean differences (MDs) and 95% confidence intervals (95% CIs).

RESULTS

Fifteen studies that compared USG and blind injections were included. No significant difference was found in the VAS score between the blind group and USG group (MD 0.41 [-0.02, 0.84]; I2 = 79%; P = .06). Subgroup analysis of the brachial bicipital groove indicated that the USG group had less pain than the blind group (MD 1.50 [0.54, 2.46]; I2 = 64; P = .002). The USG injection patients had better postoperative abduction (MD -3.08 [-5.19, -0.98], I2 = 0, P = .004) and flexion (MD -3.36 [-5.56, -1.16]; I2 = 0; P = .003) than the blind group. Additionally, the USG injection patients had better CMS scores than the blind injection patients (MD -12.95 [-25.60, -0.29]; I2 = 96; P = .04). However, subgroup analysis showed no significant difference in the subacromial bursas and glenohumeral joints of CMS score (MD -13.22 [-29.93, 3.94]; I2 = 97; P＜.0001). No significant difference was found in the SPADI, ASES score, or SDQ score between the groups.

CONCLUSIONS

Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function. However, injection in the brachial bicipital groove, is still superior to blind injection of pain relief.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

The Impact of Suprascapular Nerve Interventions in Patients with Frozen Shoulder: A Systematic Review and Meta-Analysis

BACKGROUND

Frozen shoulder is a common condition resulting in severe pain and restricted range of motion. An assessment of the effectiveness of interventions may provide an improved understanding of the development and management of frozen shoulder.

METHODS

A literature search was conducted using Embase, the Cumulative Index of Nursing and Allied Health (CINAHL), the Cochrane Central Register of Controlled Trials (CENTRAL), and National Center for Biotechnology Information PubMed using relevant terms. Studies were included if they assessed the outcomes of interventions on the suprascapular nerve that aim to improve the symptoms of frozen shoulder.

RESULTS

A database search returned 196 articles. After review, 9 articles met the inclusion criteria and were included in the analysis. Suprascapular nerve interventions (nerve block, pulsed radiofrequency lesioning) are associated with improvement in pain, motion, and function. Meta-analysis showed that pain (Hedges g, -3.084 [95% confidence interval (CI), -4.273 to -1.894]; p < 0.001) and range of motion (Hedges g, 2.204 [95% CI, 0.992 to 3.415]; p < 0.001) improved significantly following suprascapular nerve block (SSNB).

CONCLUSIONS

SSNB is associated with significant improvements in shoulder pain and range of motion in patients with frozen shoulder. Further randomized controlled trials comparing SSNB with intra-articular injection and other nonoperative treatments are required to fully define its role in the management of frozen shoulder.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

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.

A prospective, comparative study of subacromial corticosteroid injection and subacromial corticosteroid injection plus suprascapular nerve block in patients with shoulder impingement syndrome

INTRODUCTION

Efforts are recently focused on the management of shoulder impingement syndrome (SIS) with a conservative and targeted approach because of its psychosocial impact, reduction in the quality of life, the cost to the economy and its negative effect on daily activities. Therefore, many studies have been designed to evaluate and compare the effectiveness of different treatments. The main purpose of this study was to identify the effect of combination of subacromial corticosteroid injection (SCI) and suprascapular nerve block (SSNB) on shoulder impingement syndrome (SIS).

MATERIALS AND METHODS

66 patients with SIS were randomly divided into two groups (33 patients per group): Group 1: SCI; Group 2: SCI plus SSNB. The estimation of the severity of pain by the visual analogue scale (VAS) and shoulder disability using quick DASH (Disabilities of the Arm, Shoulder and Hand) were assessed at baseline and 1, 3 months post-injection.

RESULTS

The mean age of patients was 55.55 ± 10.42 years in Group 1 and 57.24 ± 12.75 years in Group 2. In steroid group, pre- and post-treatment (at 1 and 3 months) VAS/quickDASH scores were 8.64 ± 0.99/78.03 ± 9.24, 2.09 ± 0.84/15.58 ± 7.23 and 3.06 ± 1.12/25.06 ± 8.74, respectively. In steroid plus SSNB group, pre- and post-treatment (at 1 and 3 months) VAS/quickDASH scores were 8.45 ± 0.90/75.15 ± 9.86, 1.24 ± 0.43/10.88 ± 2.14 and 1.51 ± 0.56/15.51 ± 5.04, respectively. Both treatment groups showed a significant relief of pain at 1 and 3 months post-injection (p < 0.05). However, the VAS and quickDASH scores at 1 and 3 months were significantly lower in Group 2 versus Group 1 (p < 0.05).

CONCLUSION

The combination of SCI and SSNB seems to produce the long-term effect in pain relief and functional improvement.

Clinical indications for image guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part III, nerves of the upper limb

BACKGROUND

Image-guided interventional procedures of the nerves are commonly performed by physicians from different medical specialties, although there is a lack of clinical indications for these types of procedures. This Delphi-based consensus provided a list of indications on image-guided interventional procedures for nerves of the upper limb based on updated published evidence.

METHODS

An expert panel of 45 members of the Ultrasound and Interventional Subcommittees of the ESSR participated in this Delphi-based consensus study. After revision of the published papers on image-guided interventional procedures for nerves of the upper limb updated to September 2018, the experts drafted a list of statements according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus on statements regarding clinical indications was considered as strong when more than 95% of experts agreed, and broad if more than 80% agreed.

RESULTS

Ten statements were drafted on procedures for nerves of the upper limb. Only two statements reached the highest level of evidence (ultrasound guidance is a safe and effective method for brachial plexus block; ultrasound-guided non-surgical approaches are safe and effective methods to treat carpal tunnel syndrome in the short term, but there is sparse evidence on the mid- and long-term effectiveness of these interventions). Strong consensus was obtained on 6/10 statements (60%), while 4/10 statements reached broad consensus (40%).

CONCLUSIONS

This Delphi-based consensus study reported poor evidence on image-guided interventional procedures for nerves of the upper limb. Sixty percent of statements on clinical indications provided by the expert board reached a strong consensus.

KEY POINTS

• An expert panel of the ESSR provided 10 evidence-based statements on clinical indications for image-guided interventional procedures for nerves of the upper limb • Two statements reached the highest level of evidence • Strong consensus was obtained on 6/10 statements (60%), while 4/10 statements reached broad consensus (40%).