Suprascapular Nerve Block: Important Procedure in Clinical Practice

A Case of Hospitalization After Pre-operative Interscalene Nerve Block in an Ambulatory Surgery Center

Interscalene nerve block (ISB) is an effective and low-risk local anesthetic (LA) procedure that is commonly employed for shoulder surgery. While phrenic nerve involvement occurs to some degree in every ISB procedure, the incidence of hypoxemia and other clinical signs of diaphragmatic disruption is much lower. This is a case of a 36-year-old female with no underlying respiratory disease who developed hypoxemia requiring a night of observation following an ISB for a rotator cuff repair procedure in an ambulatory surgical center. Her hypoxemia was easily treated with supplemental oxygen and she made a full recovery by the next day. The use of ultrasound guidance, reduced LA volume, less potent medication, sterile fluid for optimal visualization, and extrafascial administration should be considered for all patients receiving an ISB to prevent respiratory complications.

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.

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

BACKGROUND AND OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Novel Diagnostic and Treatment Techniques for Neurogenic Thoracic Outlet Syndrome

Neurogenic thoracic outlet syndrome is a challenging condition to diagnose and treat, often precipitated by the triad of repetitive overhead activity, pectoralis minor contracture, and scapular dyskinesia. The resultant protracted scapular posture creates gradual repetitive traction injury of the suprascapular nerve via tethering at the suprascapular notch and decreases the volume of the brachial plexus cords and axillary vessels in the retropectoralis minor space. A stepwise and exhaustive diagnostic protocol is essential to exclude alternate pathologies and confirm the diagnosis of this dynamic pathologic process. Ultrasound-guided injections of local anesthetic or botulinum toxin are a key factor in confirming the diagnosis and prognosticating potential response from surgical release. In patients who fail over 6 months of supervised physical therapy aimed at correcting scapular posture and stretching of the pectoralis minor, arthroscopic surgical release is indicated. We present our diagnostic algorithm and technique for arthroscopic suprascapular neurolysis, pectoralis minor release, brachial plexus neurolysis, and infraclavicular thoracic outlet decompression.

Modern Treatment of Neurogenic Thoracic Outlet Syndrome: Pathoanatomy, Diagnosis, and Arthroscopic Surgical Technique

Compressive pathology in the supraclavicular and infraclavicular fossae is broadly termed "thoracic outlet syndrome," with the large majority being neurogenic in nature. These are challenging conditions for patients and physicians and require robust knowledge of thoracic outlet anatomy and scapulothoracic kinematics to elucidate neurogenic versus vascular disorders. The combination of repetitive overhead activity and scapular dyskinesia leads to contracture of the scalene muscles, subclavius, and pectoralis minor, creating a chronically distalized and protracted scapular posture. This decreases the volume of the scalene triangle, costoclavicular space, and retropectoralis minor space, with resultant compression of the brachial plexus causing neurogenic thoracic outlet syndrome. This pathologic cascade leading to neurogenic thoracic outlet syndrome is termed pectoralis minor syndrome when primary symptoms localize to the infraclavicular area. Making the correct diagnosis is challenging and requires the combination of complete history, physical examination, advanced imaging, and ultrasound-guided injections. Most patients improve with nonsurgical treatment incorporating pectoralis minor stretching and periscapular and postural retraining. Surgical decompression of the thoracic outlet is reserved for compliant patients who fail nonsurgical management and respond favorably to targeted injections. In addition to prior exclusively open procedures with supraclavicular, infraclavicular, and/or transaxillary approaches, new minimally invasive and targeted endoscopic techniques have been developed over the past decade. They involve the endoscopic release of the pectoralis minor tendon, with additional suprascapular nerve release, brachial plexus neurolysis, and subclavius and interscalene release depending on the preoperative work-up.

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.

Variations in the Course and Diameter of the Suprascapular Nerve: Anatomical Study

(1) Background: Suprascapular neuropathy is an important factor contributing to shoulder pain. Given the prevalence of nerve injury and nerve block in the suprascapular notch region, as well as the frequency of arthroscopic procedures on the suprascapular notch, which are recommended in shoulder pain management, its morphology is relevant from a clinical perspective. (2) Methods: Suprascapular nerve course was studied in twelve shoulders by dissection. Its diameter was measured at omohyoid level, proximal to the suprascapular notch and distal to the spinoglenoid notch. A multi-vari chart was used in order to descriptively visualize the results. The variations found were analyzed with a mixed linear model. (3) Results: In two of the six subjects, the suprascapular nerve was divided into two motor branches proximal to the superior transverse scapular ligament. An increase in diameter around the suprascapular notch was detected, with an estimated difference between diameter means of 2.008 mm at the suprascapular notch level and 2.047 mm at the spinoglenoid notch level. (4) Conclusions: A difference in the estimated diameter detected and the fact that the motor branches, which innervate supraspinatus and infraspinatus muscle, were divided proximal to the suprascapular notch may be relevant in the diagnosis and treatment of suprascapular neuropathy and arthroscopic procedures.

Median Effective Analgesic Concentration of Ropivacaine in Ultrasound-Guided Interscalene Brachial Plexus Block as a Postoperative Analgesia for Proximal Humerus Fracture: A Prospective Double-Blind Up-Down Concentration-Finding Study

Background

The innervation of the proximal humerus fracture is complicated and unclear. The use of interscalene nerve block has been effective as postoperative analgesia for patients, but the optimal concentration of usage is unknown.

Method

This study was conducted on 30 patients with ASA I or II, who were planning to undergo a proximal humerus fracture operation. A dosage of 10 ml Ropivacaine was administered for the interscalene brachial plexus block (ISBPB) as determined using the up-and-down sequential method. The initial concentration of Ropivacaine in the first patient to receive ISBPB was 0.3%. After a successful or unsuccessful postoperative analgesia, the concentration of local anesthetic was decreased or increased, respectively, by 0.05% in the next patient. We defined successful postoperative analgesia as a visual analog scale (VAS) score of < 4 at rest, within the initial 8 h after ISBPB. The analytic techniques of linear, linear-logarithmic, exponential regressions, and centered isotonic regression were used to determine the EC50 of Ropivacaine, and the residual standard errors were calculated for the comparison of “goodness of fit.”

Results

The concentration of Ropivacaine ranged from 0.1 to 0.35%. The EC50 (95% confidence interval) from 4 different statistical approaches (linear, linear-logarithmic, exponential regressions, and centered isotonic regression) were 0.222% (0.198%, 0.335%), 0.233% (0.215%, 0.453%), 0.223% (0.202%, 0.436%), and 0.232%, respectively. Among all the 4 models, the linear regression had the least residual standard error (0.1676).

Conclusion

The EC50 from the four statistical models for 10 ml Ropivacaine in ultrasound-guided ISBPB for postoperative analgesia was distributed in a narrow range of 0.222–0.233%.

Trial Registration

www.chictr.org.cn/; registration number: ChiCTR2100047231.

Associação de sintomas ansiosos e depressivos em pacientes com capsulite adesiva

Objetivo Avaliar a associação entre sintomas ansiosos e depressivos em pacientes com capsulite adesiva.

Métodos Trata-se de um estudo transversal realizado em centro único de um hospital terciário com pacientes portadores de capsulite adesiva secundária. O grupo controle não apresentava doença do ombro, tireoidopatias e nem ansiedade e/ou depressão. O instrumento utilizado foi a escala hospitalar de ansiedade e depressão. A análise da covariância foi utilizada para comparação dos escores do Hospital Anxiety and Depression Scale (HADS, na sigla em inglês) entre os grupos. O nível de significância foi de 5%.

Resultados A amostra final foi de 17 pacientes (caso) e 27 (controle). Os dados amostrais apresentaram distribuição normal por meio do teste de Shapiro-Wilk (p > 0,05). A instrumento HADS com pontuação > 0,70 (alfa de Cronbach) se mostrou confiável e com boa consistência interna. Os pacientes com capsulite adesiva, no quesito “sintomas ansiosos” (p = 0,019), relataram sintomas no patamar de “duvidosos” (média/desvio padrão = 8,88/4,50). Eles não apresentaram “sintomas depressivos” (média/desvio padrão = 6,41/3,69), apesar do p = 0,015.

Conclusão Existe uma associação positiva “duvidosa” entre sintomas ansiosos e capsulite adesiva, mas negativa para sintomas depressivos.

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.

Ultrasound-guided peripheral nerve interventions for common pain disorders

There are a number of common pain disorders that can be managed effectively by injections around or ablation of peripheral nerves. Ultrasound is a universally available imaging tool, is safe, cost-effective, and is excellent in imaging many peripheral nerves and guiding needles to the site of the nerves. This article aims to present an overview of indications and techniques of such procedures that can be effectively performed by a radiologist.

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.

"Suprascapular canal": Anatomical and topographical description and its clinical implication in entrapment syndrome

BACKGROUND

Suprascapular nerve (SN) entrapment syndrome accounts for 1-2% of all shoulder pain. The SN travels within a space between the suprascapular notch (SSN) and the spinoglenoid notch (SGN).

PURPOSE

To report a detailed topographical study of the suprascapular canal (SSC) and ultimately sort the different types of SN entrapment by its anatomical localization within the canal.

BASIC PROCEDURES

Observational study on 30 free dissected limbs of formaldehyde-fixed cadavers. The SN and vessels were traced as they passed through the SSC and the boundaries of the SSC were observed and documented. The SSC was then exposed by reflecting away the bordering muscles. Dimensions of the SSC as well as parameters of the SSN and SGN were measured using a digital caliper. Finally, a thorough literature review was made to survey the SN entrapment occurrence by site.

MAIN FINDINGS

The SSC is situated in the spinoglenoid fossa, has an average width of 13 mm, and runs underneath the supraspinatus muscle with an average distance of 25 mm between the SSN and SGN sloping in an infero-postero-lateral direction. The first segment represents the SSC entrance site and is composed of two spaces: osteofibrous and musculofibrous. The second segment is bordered by the supraspinatus muscle fascia, lateral margin of the supraspinous fossa, glenohumeral joint capsule, and the bony surface of the scapula (spinoglenoid fossa). This represents the SSC passage site. The third segment represents the SSC exit site around the spinoacromial arch at the SGN.

PRINCIPAL CONCLUSIONS

The SSC is defined as an osteofibrous canal running between the SSN and SGN enclosed by the supraspinatus fascia. It is anatomically composed of three segments: an entrance, a passage, and an exit. The distal SN passes through the SSC via five intervals that correspond to five potential sites of anatomical nerve entrapment: at the pre-entrance site, entrance site, passage site, exit site, and post-exit site. Each of those sites was found to be associated with specific causes and forms of entrapment.

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.

Randomized, controlled trial comparing respiratory and analgesic effects of interscalene, anterior suprascapular, and posterior suprascapular nerve blocks for arthroscopic shoulder surgery

Background

Interscalene brachial plexus block (ISB) provides excellent analgesia for arthroscopic shoulder surgeries but is associated with adverse effects including hemidiaphragmatic paresis. We aimed to compare the respiratory effects, forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1) between suprascapular nerve block (SSB) and ISB.

Methods

Sixty patients were recruited and randomized into ISB, anterior SSB, and posterior SSB groups. FVC, FEV1, and diaphragmatic excursion were evaluated at baseline and 30 minutes after intervention. Blocks were performed under ultrasound guidance with 15 ml of 0.5% ropivacaine. Pain scores were assessed at 1, 6, 12, and 24 hours postoperatively.

Results

The ISB group showed a reduced FVC of 31.2% ± 17.5% (mean ± SD), while the anterior and posterior SSB groups had less reduction of 3.6% ± 18.6% and 6.8% ± 6.5%, respectively (P < 0.001). The ISB group showed more reduction in diaphragmatic excursion than the anterior and posterior SSB groups (median [IQR]): −85.7% (−95.3% to −63.3%) vs. −1.8% (−13.1% to 2.3%) and −1.2% (−8.8% to 16.8%), respectively (P < 0.001). The median pain scores (IQR) in the ISB and anterior SSB groups were lower than those in the posterior SSB group at 6 hours on movement: 0 (0–2), 1.8 (0–4.5) vs. 5 (2.5–8), respectively (P = 0.002). There was no significant difference in oxycodone consumption postoperatively.

Conclusions

Anterior SSB preserves lung function and has a comparable analgesic effect as ISB. Thus, it is recommended for arthroscopic shoulder surgeries, especially in patients who have reduced lung function.

Suprascapular nerve neuropathy leads to supraspinatus tendon degeneration

BACKGROUND

Nowadays most of attention regarding rotator cuff is payed to how to reduce the failure after rotator cuff surgical repair rather than how to prevent the rotator cuff tear before surgery. The etiologies of rotator cuff tear are still unclear. As we all know, the nerve system include brain, spinal cord, sensory organs and all the neurons allover our body coordinates the homoeostasis of our body. We hypothesis that the nerve injury proximal to suprascapular nerve can leads to rotator cuff degeneration even tear.

METHODS

Thirty-six SD rats were used. A defect on the suprascapular nerve was made on the right side and a sham surgery on the nerve (expose nerve only) at the left side. The insertion of supraspinatus tendon and supraspinatus muscle were harvested for testing. Twelve rats were sacrificed for biomechanical (six rats) and histological (six rats) properties were evaluated at 3, 6, and 9 weeks after surgery, respectively.

RESULTS

Significant inferior biomechanical properties of rotator cuff were found in nerve injured side compared to the nerve intact side at 6-9 weeks. Significant muscle atrophy was found at nerve injured side from 3 to 9 weeks. The enthesis of nerve injured side showed significant excessive cell maturity, reduced cellularity, smaller metachromasia area and more type-III collagen especially at 9 weeks after surgery.

CONCLUSIONS

The neuropathy proximal to suprascapular nerve can leads to rotator cuff degeneration even tear. The nerve dysfunction maybe an important etiology for rotator cuff tear.

Distal suprascapular nerve block-do it yourself: cadaveric feasibility study

BACKGROUND

A bone landmark-based approach (LBA) to the distal suprascapular nerve (dSSN) block is an attractive "low-tech" method available to physicians with no advanced training in regional anesthesia or ultrasound guidance. The primary aim of this study was to validate the feasibility of an LBA to blockade of the dSSN by orthopedic surgeons using anatomic analysis. The secondary aim was to describe the anatomic features of the sensory branches of the dSSN.

MATERIALS AND METHODS

An LBA was performed in 15 cadaver shoulders by an orthopedic resident. Then, 10 mL of methylene blue-infused 0.75% ropivacaine was injected around the dSSN; 2.5mL of red latex solution was also injected to identify the position of the needle tip. The division and distribution of the sensory branches that originate from the suprascapular nerve were described.

RESULTS

The median distance between the dSSN and the site of injection was 1.5 cm (0-4.5 cm). The most common injection site was at the proximal third of the scapular neck (n = 8). Fifteen dSSNs were stained proximal to the origin of the most proximal sensory branch. All 15 dSSNs gave off 3 sensory branches that innervated the posterior glenohumeral capsule, the subacromial bursa, and the coracoclavicular and acromioclavicular ligaments.

CONCLUSIONS

An LBA for anesthetic blockade of the dSSN by an orthopedic surgeon is a simple, reliable, and accurate method. Injection close to the suprascapular notch is recommended to involve the dSSN proximally and its 3 sensory branches.

Post-operative analgesia for shoulder arthroscopic surgeries: A comparison between inter-scalene block and shoulder block

Background and Aims

Shoulder arthroscopic surgeries can produce intense post-operative pain. Inter-scalene block (ISB) provides good analgesia after shoulder surgery, but concerns over its associated risks have prompted the search for alternatives. Shoulder block (SHB), which includes suprascapular block along with axillary nerve (AN) block, was recently proposed as an alternative to ISB, but evidence of its efficacy is conflicting. The aim of our study was to compare SHB with ISB in shoulder surgery for post-operative analgesia.

Methods

A total of 76 patients scheduled for shoulder arthroscopic surgery were equally divided into 2 groups of 38 patients each: ISB group and SHB group. Both the nerve blocks were achieved by using ultrasound and a nerve stimulator. Visual analogue scale (VAS) scores were evaluated at 1, 4, 6, 12 and 24 h post-operatively. The time to first analgesia request, total analgesic requirement for 24 h post-operatively, patient satisfaction and any complications were recorded.

Results

SHB provided equivalent analgesia to ISB in terms of post-operative VAS scores. Time to first analgesic request was 6.2 ± 1.3 h in ISB group and 5.9 ± 1.2 h in SHB group, which was not statistically significant. Complications like subjective dyspnoea and weakness of arm were significantly higher in ISB group compared to SHB group. Patient satisfaction scores were also significantly higher in SHB group compared to ISB group.

Conclusion

SHB is as effective as ISB for post-operative pain relief and with fewer complications due to selective blockade of suprascapular and axillary nerves.

A retrospective case series of ultrasound-guided suprascapular nerve pulsed radiofrequency treatment for hemiplegic shoulder pain in patients with chronic stroke

Purpose

Hemiplegic shoulder pain (HSP) is the most common pain condition after stroke. Pulsed radiofrequency (PRF) treatment of the suprascapular nerve (SSN) effectively relieves shoulder pain conditions. To date, there is no study about the effects of PRF treatment for HSP. Thus, our aim was to report on a case series about its use in chronic stroke.

Patients and methods

Six chronic stroke patients with HSP (visual analog scale [VAS] score for pain ≥30 mm) underwent ultrasound-guided SSN PRF treatment. All were evaluated before treatment and at 4 and 16 weeks of follow-up. The main outcome was VAS score. Secondary outcomes were Modified Ashworth Scale, shoulder passive range of motion (PROM), Disability Assessment Scale (DAS), Fugl-Meyer Assessment, and EuroQol-5 dimension questionnaire (EuroQol-5D) scores.

Results

As compared with baseline, improvement was observed in the following parameters: VAS for pain (at 4 weeks, P=0.023; at 16 weeks, P=0.023); shoulder PROM for abduction (at 4 weeks, P=0.023; at 16 weeks, P=0.024), flexion (at 4 and 16 weeks, P=0.024), extension (at 4 and 16 weeks, P=0.02), and external rotation (4 and 16 weeks, P=0.02); DAS for hygiene (at 4 and 16 weeks, P=0.024), dressing (at 4 weeks, P=0.02; at 16 weeks, P=0.024), and pain (at 4 weeks, P=0.024; at 16 weeks, P=0.023); and EuroQol-5D (at 4 and 16 weeks, P=0.024).

Conclusion

Our observations support the use of ultrasound-guided SSN PRF treatment for HSP in chronic stroke patients.

Nerves Around the Shoulder: What the Radiologist Should Know?

Peripheral neuropathies of the shoulder are common and could be related to traumatic injury, shoulder surgery, infection or tumour but usually they result from an entrapment syndrome. Imaging plays an important role to detect the underlying causes, to assess the precise topography and the severity of nerve damage. The key points concerning the imaging of nerve entrapment syndrome are the knowledge of the particular topography of the injured nerve, and the morphology as well signal modifications of the corresponding muscles. Magnetic Resonance Imaging best shows these findings, although Ultrasounds and Computed Tomography sometimes allow the diagnosis of neuropathy.

Suprascapular and Interscalene Nerve Block for Shoulder Surgery

Background

Interscalene block provides optimal shoulder surgery analgesia, but concerns over its associated risks have prompted the search for alternatives. Suprascapular block was recently proposed as an interscalene block alternative, but evidence of its comparative analgesic effect is conflicting. This meta-analysis compares the analgesic effect and safety of suprascapular block versus interscalene block for shoulder surgery.

Methods

Databases were searched for randomized trials comparing interscalene block with suprascapular block for shoulder surgery. Postoperative 24-h cumulative oral morphine consumption and the difference in the area under curve for pooled rest pain scores were designated as primary outcomes. Analgesic and safety outcomes, particularly block-related and respiratory complications, were evaluated as secondary outcomes. Results were pooled using random-effects modeling.

Results

Data from 16 studies (1,152 patients) were analyzed. Interscalene block and suprascapular block were not different in 24-h morphine consumption. The difference in area under the curve of pain scores for the 24-h interval favored interscalene block by 1.1 cm/h, but this difference was not clinically important. Compared with suprascapular block, interscalene block reduced postoperative pain but not opioid consumption during recovery room stay by a weighted mean difference (95% CI) of 1.5 cm (0.6 to 2.5 cm; P &lt; 0.0001). Pain scores were not different at any other time. In contrast, suprascapular block reduced the odds of block-related and respiratory complications.

Conclusions

This review suggests that there are no clinically meaningful analgesic differences between suprascapular block and interscalene block except for interscalene block providing better pain control during recovery room stay; however, suprascapular block has fewer side effects. These findings suggest that suprascapular block may be considered an effective and safe interscalene block alternative for shoulder surgery.

Anesthesia and Analgesia in the Patient with an Unstable Shoulder

Introduction:

The patient with an unstable shoulder represents a challenge for the anesthesiologist. Most patients will be young individuals in good health but both shoulder dislocation reduction, a procedure that is usually performed under specific analgesia in an urgent setting, and instability surgery anesthesia and postoperative management present certain peculiarities.

Material and Methods:

For the purpose of the article, 78 references including clinical trials and reviews were included. The review was organized considering the patient that presents an acute shoulder dislocation and the patient with chronic shoulder instability that requires surgery. In both cases the aspects like general or regional anesthesia, surgical positions and postoperative pain management were analyzed.

Conclusion:

The patient with an acutely dislocated shoulder is usually managed in the emergency room. Although reduction without analgesia is often performed in non-medical settings, an appropriate level of analgesia will ease the reduction procedure avoiding further complications. Intravenous analgesia and sedation is considered the gold standard but requires appropriate monitorization and airway control. Intraarticular local analgesic injection is considered also a safe and effective procedure. General anesthesia or nerve blocks can also be considered. The surgical management of the patient with shoulder instability requires a proper anesthetic management. This should start with an exhaustive preoperative evaluation that should be focused in identifying potential respiratory problems that might be complicated by local nerve blocks. Intraoperative management can be challenging, especially for patients operated in beach chair position, for the relationship with problems related to cerebral hypoperfusion, a situation related to hypotension events directly linked to patient positioning. Different nerve blocks will help attaining excellent analgesia both during and after the surgical procedure. An interescalene nerve block should be considered the best technique, but in certain cases, other blocks can be considered.

Physiotherapist-led suprascapular nerve blocks for persistent shoulder pain: Evaluation of a new service in the UK

INTRODUCTION

This service evaluation explored and reported findings from a new physiotherapist-led service offering suprascapular nerve blocks (SSNBs) to patients with persistent shoulder pain.

METHODS

We collected data before the SSNB injection and at the 6-weeks and 6-month follow-up from consecutive patients with persistent shoulder pain being treated by physiotherapists or an anaesthetist. Outcomes were patient-reported pain (numerical rating scale [NRS 0 to 10]), patient-specific functional score (PSFS) and health-related quality of life [the EuroQol five dimensions questionnaire (EQ5D-5 L)]. Exploratory analyses compared baseline and follow-up scores within each clinician delivery group (physiotherapists, anaesthetist).

RESULTS

Forty patients (mean age 57 years [standard deviation {SD} 12]; 63% female) received an SSNB from a physiotherapist, eight patients (mean age 59 years [SD 11]; female 88%) received an SSNB from an anaesthetist. At the 6-week follow-up, the physiotherapy group showed a mean reduction in pain (on the NRS): 2.2 (95% confidence interval [CI] 1.3 to 3.0) and an improvement in function (on the PSFS): -1.3 (95% CI -1.9 to -0.4). Similar changes were found in those treated by the anaesthetist (pain: 1.3 [95% CI -1.18 to 3.80]; function: -1.4 (95% CI -3.18 to 0.35]). Very small changes, that were not statistically significant, were found in EQ5D-5 L scores. At the 6-month follow-up, the mean reduction in pain (NRS) was maintained at 2.0 (95% CI 0.99 to 2.95) for the physiotherapy group.

CONCLUSION

The results provide early, exploratory evidence that patients with persistent shoulder pain treated by physiotherapists using palpation-guided SSNBs achieve clinically important changes in pain and function in the short and medium term.

Suprascapular nerve block for the treatment of hemiplegic shoulder pain in patients with long-term chronic stroke: a pilot study

Hemiplegic shoulder pain is the most common pain condition after stroke. Suprascapular nerve block is an effective treatment for shoulder pain. The aim of this pilot study was to evaluate the effects of suprascapular nerve block on pain intensity, spasticity, shoulder passive range of motion, and quality of life in long-term chronic stroke patients with hemiplegic shoulder pain. Ten chronic stroke patients (over 2 years from onset) with hemiplegic shoulder pain graded ≥30 mm on the Visual Analogue Scale underwent suprascapular nerve block injection with 1 mL of 40 mg/mL methylprednisolone and 10 mL 0.5% bupivacaine hydrochloride. Main outcome was the Visual Analogue Scale evaluated before and after nerve block at 1 h, 1 week, and 1 month. Secondary outcomes were the modified Ashworth scale and the shoulder elevation, abduction, and external rotation passive range of motion evaluated before the nerve block and after 1 h as well as the American Chronic Pain Association Quality of Life Scale evaluated before and after nerve block at 1 month. The Visual Analogue Scale significantly improved after nerve block at 1 h (P = 0.005) and 1 week (P = 0.011). Significant improvements were found at 1 h after nerve block in the modified Ashworth scale (P = 0.014) and the passive range of motion of shoulder abduction (P = 0.026), flexion (P = 0.007), and external rotation (P = 0.017). The American Chronic Pain Association Quality of Life Scale significantly improved at 1 month after nerve block (P = 0.046). Our findings support the use of suprascapular nerve block for treating hemiplegic shoulder pain in long-term chronic stroke patients.

The Effect of the Modified Lateral Suprascapular Block on Shoulder Function in Patients With Chronic Shoulder Pain

Background:

Suprascapular nerve block (SSNB) is commonly used in pain therapy for patients with chronic shoulder pain. The effect of SSNB on shoulder function has, however, not been investigated so far. If in shoulder function, i.e. the range of motion is increased after application of the nerve block, it can be expected that subsequent physiotherapy, besides being less painful, is also more effective in terms of restoring shoulder mobility.

Objectives:

Our aim was to evaluate the effect of SSNB on shoulder function, in patients with chronic shoulder pain.

Patients and Methods:

Patients were evaluated using the Constant-Murley Score (CMS) and number rating scale values for pain. The SSN was blocked using the Feigl approach, with 5 ml ropivacaine 0.5%. Shoulder function and pain were assessed 60 minutes and 24 hours after the block.

Results:

Totally, 20 patients completed the study. The CMS and pain scores significantly improved after the block.

Conclusions:

The use of the modified lateral SSNB of Feigl significantly reduces pain and increases shoulder function, in chronic shoulder pain.