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OBJECTIVE: To develop an ultrasound (US)-guided ventral approach to the brachial plexus (BP) and evaluate nerve anatomy and staining in barred owl cadavers. STUDY DESIGN: Prospective, cadaveric study. ANIMALS: Eleven adult male and female barred owl cadavers with a body mass of 0.43-0.98 kg. METHODS: Eleven frozen cadavers were thawed for 48 hours, weighed and assigned a body condition score. Ten cadavers were placed in dorsal recumbency with wings abducted. US-guided visualization of the BP was achieved by placing a 13-6 MHz linear probe over the ventral aspect of the scapulohumeral joint, parallel to the sternum. A 22 gauge, 50 mm insulated needle was advanced in-plane in a caudal-to-cranial direction. In each owl, injection targeting one BP was performed with 0.4 mL kg-1 of a 1:1 0.5% ropivacaine and 1% methylene blue solution. Dissection was performed 15 minutes postinjection. Nerve staining was deemed successful if ≥ 1 cm of circumferential staining was achieved. The eleventh owl cadaver was injected with a 1:1 solution of 1% methylene blue and 74% ioversol contrast into both wings, and computed tomography (CT) was performed just before and 15 minutes after injection. RESULTS: The BP was clearly identified ultrasonographically in cadavers weighing > 0.5 kg. An injectate volume of 0.4 mL kg-1 provided complete staining of the BP branches in all cadavers. CT scan revealed no contrast within the coelomic cavity. CONCLUSIONS AND CLINICAL RELEVANCE: The US-guided BP injection using a ventral approach was easily performed in barred owl cadavers weighing > 0.5 kg. The injection of 0.4 mL kg-1 of a ropivacaine-dye solution resulted in complete staining of the BP branches in all wings, suggesting that this technique could provide analgesia for structures distal to the scapulohumeral joint. Clinical studies are necessary to confirm the safety and efficacy of this technique in barred owls and other bird species.

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During dissection sessions for undergraduate students, the unilateral accessory clavicular head of the sternocleidomastoid muscle was observed in three cadavers. These accessory heads extended from the middle third of the clavicle and joined the sternocleidomastoid muscle in the middle third. The variations in the sternocleidomastoid muscle may be attributed to abnormal mesodermal splitting or fusion failure during the development of the post-sixth branchial arch. Anomalies of the sternocleidomastoid may be misdiagnosed as cervical dystonia, fibromatosis colli, or muscular spasm. In rare cases, an accessory head could result in torticollis in adults. These anomalies warrant particular attention during interventional procedures conducted by anesthesiologists. The internal jugular vein is accessed at the lesser supraclavicular fossa for cannulation during central venous access and temporary hemodialysis. Variations in its anatomy can pose challenges during these procedures. Moreover, the clavicular head may be utilized for muscle flaps in the upper neck and occipital regions.

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Background and Aims: Perineural catheters inserted through the costoclavicular (CC) technique of infraclavicular brachial plexus are helpful for postoperative analgesia. This trial compared postoperative local anaesthetic (LA) consumption in an ultrasound (US)-guided perineural catheter inserted by the CC technique with the conventional lateral sagittal (LS) technique. Methods: Eighty American Society of Anesthesiologists (ASA) I/II patients scheduled for upper limb orthopaedic surgery were randomly assigned to receive a perineural catheter by either the CC technique (Group CC) or LS technique (Group LS). Postoperatively, all patients received patient-controlled regional analgesia (PCRA): bolus-only regime with 0.125% bupivacaine 6 ml and a lock-out interval of 20 minutes. The primary outcome was the 24 h LA consumption. The secondary outcomes were time of activation of PCRA, pain scores, patient satisfaction scores, and block-related complications. Categorical variables are presented as frequency, while continuous variables are expressed as mean [standard deviation (SD)] or median [interquartile range (IQR)]. An independent t-test or Mann-Whitney U-test was used to compare these continuous variables. A P value less than 0.05 was considered to be statistically significant. Results: Patients in Group CC required less LA 24 h postoperatively (P < 0.001) and more time to activate PCRA (P = 0.003). The mean 24 h LA requirement was 83.35 (SD: 31.92) in Group CC as compared to 121.40 (SD: 48.51) ml in Group LS. They also reported better satisfaction scores (P = 0.001). Pain scores were comparable at all time points. Postoperatively, one patient in Group CC complained of paraesthesia, which subsided on removal of the catheter. Conclusion: Patients receiving post-operative analgesia by the CC catheter require lesser 24 h LA and report better satisfaction than those receiving analgesia through the LS technique.

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Background and Aims: The infraclavicular brachial plexus block (ICB) provides analgesia and anaesthesia of the upper limb. It is given using the classical or the more recently described costoclavicular (CC) approach at the level of cords. This systematic review aimed to assess which approach is better for the ICB in terms of onset, performance, and safety. Methods: This PROSPERO (vide registration number CRD42022361636) registered meta-analysis included randomised trials of patients undergoing upper limb surgery in ultrasound-guided ICB from MEDLINE, EMBASE, SCOPUS, and IRCTP from inception to March 2023. The quality of evidence was assessed using GradePro software. The primary outcomes were sensory and motor block onset time and the number of patients having complete block at 30 minutes. Secondary outcomes included block performance time (BPT), number of attempts, duration of the block, and any incidence of complications. Results: Five trials with 374 adult patients (classic = 185, CC = 189) were included. No significant difference was found in the sensory (Mean difference (MD): 1.44 minutes [95% confidence interval (CI): 3.06, 5.95]; I2 = 95%; very low level of evidence (LOE); P = 0.53) and motor block onset times (MD: 0.83 minutes [95% CI: 0.96, 2.62]; I2 = 84%; very low LOE P = 0.36) and BPT (MD: 5.06 seconds [95% CI: 38.50, 48.63]; I2 = 98%; very low LOE; P = 0.82) in classic and CC approach of ICB. Trial sequential analysis revealed our sample size to be 0.65% of the required sample size to achieve 80% power, deeming our study underpowered. Conclusion: Costoclavicular approach was not superior or inferior to the classical technique for infraclavicular brachial plexus block. However, the quality of evidence is low and further studies are needed to corroborate the findings.

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The brachial plexus, which supplies the upper limb, extends from the interscalene triangle in the root of the neck to the axilla and is closely related to the subclavian and axillary arteries. Variations in the formation, branching pattern, and relations are profound, and it is generally stated that variant anatomy of the plexus appears to be a rule rather than an exception. In previous studies, it was hypothesized that the anomalous development of the subclavian-axillary stem and the persistence of intersegmental arteries could induce variations in the plexus. In this study, all three cords of the brachial plexus (lateral, medial, and posterior) and their terminal branches are consistently found lateral to the third part of the axillary artery. Most of the studies reported variation in one or the other cord or its branches, but very few studies have reported about all cords lateral to the brachial plexus. The brachial plexus variations are usually also associated with the variations in the branches of the axillary artery, but in this study, no such variation is noted in the branches of the axillary artery. These differences impact the methods of surgery and the application of regional anesthesia. For successful outcomes, it is important to know how neurovascular relationships work, such as where the cords are in relation to the axillary artery. We report an interesting case of all cords and their branches positioned lateral to the axillary artery in the axilla in an adult male cadaver.

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INTRODUCTION: A costoclavicular brachial plexus block is an emerging infraclavicular approach that targets the cords lateral to the axillary artery, providing rapid onset of sensory-motor blockade. However, the incidence of hemi-diaphragmatic paralysis (HDP), a potential complication, remains unclear compared to the widely used supraclavicular (SC) approach. This study aimed to compare the incidence of HDP between ultrasound-guided costoclavicular and SC brachial plexus blocks. OBJECTIVES: To compare the influence of ultrasound-guided SC and costoclavicular brachial plexus blocks on diaphragmatic excursion, thickness, and contractility along with pulmonary function. MATERIALS AND METHODS:  This prospective, randomized, observer-blinded controlled trial included 60 patients undergoing below-shoulder surgeries. Patients were randomized to receive either ultrasound-guided SC (Group S) or costoclavicular (Group C) brachial plexus block with 0.5% levobupivacaine. The diaphragmatic function was assessed using ultrasonographic evaluation of diaphragm thickness and diaphragmatic thickness fraction (DTF) pre- and postblock. Pulmonary function tests (PFTs) (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow rate (PEFR)) were performed preblock and two hours postblock. Block characteristics were compared. RESULTS: The SC group exhibited a significantly larger reduction in DTF from preblock to postblock compared to the costoclavicular group (mean ΔDTF: 34.38% vs. 14.01%, p<0.01). Both groups showed significant declines in FVC, FEV1, and PEFR postblock, but the magnitude of deterioration was significantly greater in the SC group, displaying no significant difference in block characteristics. CONCLUSION: The costoclavicular brachial plexus block demonstrated superior preservation of diaphragmatic contractility and lesser deterioration of PFTs compared to the SC approach while being equally effective. These findings highlight the potential benefits of the costoclavicular technique in minimizing diaphragmatic dysfunction and respiratory impairment, particularly in patients at risk for respiratory complications.

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Background and Aims: The upper thoracic (T2) erector spinae plane block (UT-ESPB) has been proposed as an alternative to interscalene brachial plexus block for postoperative analgesia in shoulder surgery. The current study was conducted to evaluate the same. Material and Methods: Patients scheduled for shoulder surgery under general anesthesia (GA) received ultrasound-guided UT-ESPB. The outcomes measured were diaphragmatic movements, block characteristics, and quality of recovery at 24 h. Results: A total of 43 patients were recruited. The incidence of phrenic nerve palsy was 0%. The sensory level achieved by the maximum number of patients at the end of 30 min was C7-T5 level, and none had a motor block. Forty-two percent of patients did not require rescue analgesia till 24 h postoperative. In the rest of the patients, the mean (SD) duration of analgesia was 724.2 ± 486.80 min, and the mean postoperative requirement of fentanyl was 98.80 ± 47.02 µg. The median pain score (NRS) during rest and movement is 2 to 3 and 3 to 4, respectively. The median quality of recovery score at the end of 24 h after the block was 14 (15-14). Conclusion: The upper thoracic ESPB resulted in a sensory loss from C7-T5 dermatomes without any weakness of the diaphragm and upper limb. However, the block was moderately effective in terms of the total duration of analgesia, postoperative pain scores, analgesic requirement, and quality of recovery in patients undergoing proximal shoulder surgeries under GA. Further studies are required to establish its role due to its poor correlation with sensory spread.

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Background: Several regional anesthesia (RA) techniques have been described for distal upper limb surgery. However, the best approach in terms of RA block success rate and safety is not well recognized. Objective: To assess and compare the surgical anesthesia and efficacy of axillary brachial plexus block with other RA techniques for hand and wrist surgery. The attainment of adequate surgical anesthesia 30 min after block placement was considered a primary outcome measure. Additionally, successful block outcomes were required without the use of supplemental local anesthetic injection, systemic opioid analgesia, or the need to convert to general anesthesia. Methods: We performed a systematic search in the following databases: MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and CENTRAL. RCTs comparing axillary blocks with other brachial plexus block techniques, distal peripheral forearm nerve block, intravenous RA, and the wide-awake local anesthesia no tourniquet (WALANT) technique were included. Results: In total, 3070 records were reviewed, of which 28 met the inclusion criteria. The meta-analysis of adequate surgical anesthesia showed no significant difference between ultrasound-guided axillary block and supraclavicular block (RR: 0.94 [0.89, 1.00]; p = 0.06; I2 = 60.00%), but a statistically significant difference between ultrasound-guided axillary block and infraclavicular block (RR: 0.92 [0.88, 0.97]; p < 0.01; I2 = 53.00%). Ultrasound-guided infraclavicular blocks were performed faster than ultrasound-guided axillary blocks (SMD: 0.74 [0.30, 1.17]; p < 0.001; I2 = 85.00%). No differences in performance time between ultrasound-guided axillary and supraclavicular blocks were demonstrated. Additionally, adequate surgical anesthesia onset time was not significantly different between ultrasound-guided block approaches: ultrasound-guided axillary blocks versus ultrasound-guided supraclavicular blocks (SMD: 0.52 [-0.14, 1.17]; p = 0.12; I2 = 86.00%); ultrasound-guided axillary blocks versus ultrasound-guided infraclavicular blocks (SMD: 0.21 [-0.49, 0.91]; p = 0.55; I2 = 92.00%). Conclusions: The RA choice should be individualized depending on the patient, procedure, and operator-specific parameters. Compared to ultrasound-guided supraclavicular and infraclavicular block, ultrasound-guided axillary block may be preferred for patients with significant concerns of block-related side effects/complications. High heterogeneity between studies shows the need for more robust RCTs.

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Background and Aim: There is no consensus on the appropriate use of mixtures of local anaesthetic drugs in various combinations for nerve blocks. We intended to compare short-acting lignocaine and long-acting ropivacaine as a mixture versus undiluted sequential injections on block characteristics of ultrasound-guided (USG) supraclavicular brachial plexus block for upper limb surgeries. Methods: A double-blinded randomised study was conducted on 64 adult patients scheduled for upper limb surgery who received 15 mL each of 2% lignocaine with adrenaline and 0.75% ropivacaine as a 1:1 mixture in the mixed group (Group M) or sequential injections in the sequential group (Group S) by using a USG technique. The primary outcome was the percentage of participants with complete four nerve sensory blocks at 10 minutes post block injection. Secondary outcomes were sensory and motor block characteristics till 30 minutes, total duration of analgesia, sensory and motor block, and complications. Results: Demographic characteristics and time taken for the procedure were similar. The percentage of participants with a complete four-nerve sensory block at 10 minutes was higher in Group S (69%) versus Group M (41%) (P = 0.04). Complete sensory and motor block rates were similar at 30 minutes. The block procedure time, total duration of analgesia, and sensory and motor block were similar in both groups. There were no major complications. Conclusion: Sequential lignocaine-ropivacaine, compared to the mixed injection technique, has a higher initial rate of sensory and motor block onset with a similar total block duration.

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Background: Ultrasound (US)-guided costoclavicular block (CCB) is a promising new approach to brachial plexus (BP) block which is increasingly being utilized. Conventionally, the costoclavicular space (CCS) has been described to contain three cords. However, there may be variations in the neural pattern of the BP which is important to know to prevent inadvertent injury. We intend to describe the variations in neural patterns from retrospective scans of patients receiving costoclavicular BP block. Methods: The stored US images of patients who had received BP block using the CCB for surgery at the level of the elbow or below in the last year (from March 2021 to March 2022) were analyzed by two investigators independently. The clinical data were retrieved from the records of the same patients for the study outcomes. We collated the variations of the neural pattern, the number of neural structures seen, and the echogenicity of the structures in the costoclavicular BP space. Results: In the CCS, the median number of neural structures was 4.5 (minimum of 3 to maximum of 8). With the BP lateral to the axillary artery and sandwiched between the subclavius-pectoralis minor superiorly and the serratus anteriorly inferiorly, numerous variations in the neural structures were noted. The most common arrangement was caterpillar-like (28.6%) and pecker-like (20.3%). The neural structures were found to be hypoechoic in the majority (66%). Conclusion: The CCS hosts several mostly hypoechoic neural structures which may be the variations of the cords or the extension of BP divisions. These new findings have been unreported in the recent past.

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Upper extremity injuries are frequent in athletes which may require surgeries. Regional anesthesia for postoperative analgesia is important to aid recovery, and peripheral nerve blocks for surgical anesthesia enable surgeries to be performed without general anesthetics and their associated adverse effects. The relevant nerve block approaches to anesthetize the brachial plexus for elbow, wrist and hand surgeries are discussed in this article. There is very limited margin for error when performing nerve blocks and multimodal monitoring approach to reduce harm are outlined. Lastly, the importance of obtaining informed consent prior to nerve block procedures should not be overlooked.

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BACKGROUND: Previous studies have shown that ultrasound guided costoclavicular block may require a double shot to provide adequate, rapid sensory and motor blockade. In this trial, we hypothesized that if the corner pocket approach (between axillary artery and median cord) is used instead of the central approach (at the midpoint of the 3 cords) when performing single-shot costoclavicular block, the onset of blockade would be non-inferior to the double-shot technique. METHOD: Ninety patients undergoing upper limb surgery were randomized to 2 groups for ultrasound-guided costoclavicular block (CCB) at a tertiary hospital. One group received ultrasound guided single-shot CCB using the corner pocket approach and other received ultrasound guided double-shot - the first shot at the centre of the 3 cords and the second between the axillary artery and the median cord. An observer blinded to group assignment recorded blockade onset time (defined as the time required to achieve a minimal sensorimotor composite score of 14 out of 16 points). RESULTS: Of the 101 patients assessed for eligibility, 90 were recruited over period of 1 year (February 2022 to January 2023), with 45 in each group. Onset time was 22.1 ±â€¯3.1 min in the single-shot group and 22.4 ±â€¯2.9 min in the double-shot group. This difference was insignificant (P = .3). CONCLUSION: Time to onset of blockade and full anaesthesia are similar in single-shot corner pocket CCB vs double-shot CCB. Further studies are required to determine the minimum effective volume of local anaesthetic required for the described technique.

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Background/Objectives: Intravenous dexmedetomidine (DEX) can increase the analgesia duration of peripheral nerve block; however, its effect in combination with superior trunk block (STB) remains unclear. We examined whether combining single-shot STB (SSTB) with intravenous DEX would provide noninferior postoperative analgesia comparable to that provided by continuous STB (CSTB). Methods: Ninety-two patients scheduled for elective arthroscopic rotator cuff repair were enrolled in this prospective randomized trial. Patients were randomly assigned to the CSTB or SSTB + DEX group. Postoperatively, each CSTB group patient received 15 mL of 0.5% ropivacaine and a continuous 0.2% ropivacaine infusion. Each SSTB group patient received a 15 mL postoperative bolus injection of 0.5% ropivacaine. DEX was administered at 2 mcg/kg for 30 min post anesthesia, then maintained at 0.5 mcg/kg/h till surgery ended. Pain scores were investigated every 12 h for 48 h post operation, with evaluation of rebound pain incidence and opioid consumption. Results: The SSTB + DEX group had significantly higher median pain scores at 12 h post operation (resting pain, 8.0 vs. 3.0; movement pain, 8.0 vs. 5.0) and a higher incidence of rebound pain (56% vs. 20%) than the CSTB group. However, no significant between-group differences were observed in pain scores postoperatively at 24, 36, or 48 h. The CSTB group required less opioids and fewer rescue analgesics within 12-24 h post operation than the SSTB + DEX group. Conclusions: Compared with CSTB, SSTB + DEX required additional adjuvant or multimodal analgesics to reduce the risk and intensity of postoperative rebound pain in patients who underwent arthroscopic rotator cuff repair.

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BACKGROUND: The costoclavicular space serves as an alternative approach to the infraclavicular brachial plexus block, and numerous studies in adults have demonstrated promising outcomes for distal upper limb surgery. Blocking the brachial plexus at this level is potentially advantageous because the cords are relatively superficial, located in close proximity to each other and easily identified using ultrasound. AIMS: This study aimed to assess the success rate and feasibility of costoclavicular block in children undergoing unilateral below elbow upper limb surgery. METHODS: Thirty children aged 2-12 years scheduled for unilateral below elbow surgery under general anesthesia were included. Costoclavicular block was performed under ultrasound and nerve stimulator guidance with 0.5% ropivacaine, 0.5 mL/kg. Success was evaluated based on the absence of significant hemodynamic response to skin incision made 20 min after the block. The sono-anatomy of costoclavicular space, ease of needling, complications, and the post-operative pain scores were assessed. RESULTS: The mean age and weight of the children were 6.5 ± 3.8 years and 19.7 ± 9.1 kg, respectively. The success rate of costoclavicular block in our cohort is 100%. Sonographic visualization was graded as excellent (Likert Scale 2) in 90% of cases. The plexus was located at a depth of 1.4 ± 0.3 cm from the skin, the lateral extent of cords from the artery was 0.8 ± 0.4 cm and they were observed inferior and lateral to the artery. The mean needling time was 3.6 ± 1.1 min. None of the children experienced complications such as vascular or pleural puncture, hematoma, Horner's syndrome or diaphragmatic palsy. Postoperative pain scores were low, and no rescue analgesia was required. CONCLUSIONS: In conclusion, the costoclavicular block exhibited a notably high success rate in pediatric population. This study substantiates that the three cords of the brachial plexus are consistently visible and superficial during ultrasound examination using this approach, confirming their separation from vascular structures and the reliable achievement of blockade without observed complications.

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Introduction: The axillary brachial plexus block is a popular nerve block for forearm, wrist, and hand surgery. The aim of this study was to assess the effectiveness of perineural administration of dexamethasone as an adjunct to lidocaine with adrenaline on the onset of sensory block and early postoperative analgesia in trans-arterial axillary brachial plexus block. Methodology: This single-centered prospective cohort study recruited 68 adult patients, 34 in each groups. The frequently used 8 mg dexamethasone combined with 1% lidocaine and adrenaline was investigated. The normality of the data was checked using the Shapiro-Wilk test. An independent t-test was used to compare the mean values of symmetric numeric data. Categorical variables between the two groups were analyzed using χ2. The Mann-Whitney U test and Kaplan-Meier method using the log-rank test were used to compare asymmetric numeric data, and a P-value of <0.05 was considered as significant. Results: The median onset time of sensory block was comparable between the nonexposed (24(6) min) and exposed group (24(6) min) (P=0.068). However, the duration of sensory block was significantly longer in the exposed group (235.5±37.51 min) than the nonexposed group (172.76±28.19 min) (P<0.001). The time to the first analgesic request was significantly longer in the exposed than the nonexposed group (P<0.01). Postoperative pain scores were significantly lower at 4 and 8 h in the exposed group (P<0.05). Conclusion and recommendations: The addition of 8 mg dexamethasone to 1% lidocaine with adrenaline solution in trans-arterial axillary brachial plexus block for ambulatory elective hand, wrist, and forearm surgeries prolonged the duration of sensory blockade and the first analgesic request time but did not reduce the onset time of sensory block. The authors recommend the addition of 8 mg dexamethasone to 1% lidocaine with adrenaline solution to prolong the duration of sensory block and the first analgesic request time.

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Background and Objectives: Reducing opioid exposure in common pediatric surgeries is of paramount importance. This study aimed to assess the efficacy of regional nerve blocks in reducing opioid exposure while preserving high success rates. Materials and Methods: We conducted a retrospective matched cohort study (1:1) including patients with elbow fractures < 12 years old who underwent treatment with percutaneous pinning. Patients were divided into general-anesthesia (GA) and GA-followed-by-supraclavicular-brachial-plexus-block (GA-SCB) groups. The primary outcome was the number of patients administered postoperative rescue opioids. The secondary outcomes included intraoperative and postoperative opioid administration, the time to first request for rescue analgesia, pain scores, block success rate, block performing time, and block-related complications. Results: In a total of 478 patients, 363 underwent percutaneous pinning, and 86 were cohort-matched (GA: n = 43, GA-SCB: n = 43). On the first postoperative day, 34 (79.0%) patients in the GA group were administered postoperative rescue opioids, compared with 12 (27.9%) in the GA-SCB group (p < 0.001). All the patients in the GA-SCB group were opioid-free during the intraoperative period. No SCB-associated complications were observed. Total opioid consumption was significantly lower in the GA-SCB group than in the GA group until the first postoperative day (GA vs. GA-SCB, 3.2 ± 3.0 mg vs. 0.9 ± 1.8 mg, p < 0.001). Conclusions: SCB application in pediatric patients who underwent elbow fracture surgery significantly reduced opioid exposure and had a high success rate when performed using ultrasound guidance by an expert. Furthermore, the complication risk and surgical delay were minimal.

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Background: Arthroscopic rotator cuff repair (ARCR) is a minimally invasive surgical technique. However, it is challenging to control postoperative pain. This study aimed to investigate the difference between a single-shot interscalene block and a combined continuous block for ARCR. Methods: Ninety-four patients who underwent ARCR were included in this study. In the preceding period, 43 patients received a single-shot interscalene block and continuous postoperative intravenous opioid infusion (Single group). In the posterior period, 51 patients received a single-shot interscalene block preoperatively and a continuous block postoperatively (Continuous group). Their mean age at surgery was 64.9 years (range, 43-83 years). The mean follow-up period was 25.4 months (range, 24-54 months). The numerical rating scale (NRS) of pain was evaluated immediately after the surgery, at rest, and at night for 1-4 days after the surgery. One day postoperatively, the amount of food taken was assessed from 0 % (no food intake) to 100 % (all food taken). The University of California at Los Angeles (UCLA) shoulder score, range of motion (ROM), and isometric shoulder strength were evaluated. Results: NRS at rest in the Continuous group on the day of surgery was 3.7 ± 2.5. This was significantly lower than in the Single group (5.2 ± 1.8) (P = 0.002). NRS at rest in the Continuous group on the second day after surgery was 3.0 ± 2.1, significantly lower than in the Single group (3.9 ± 1.8) (P = 0.04). The amount of food taken in the morning in the Continuous group was 61 % ± 37 %, which was significantly greater than in the Single group (35 % ± 41 %) (P = 0.004). The ROM of extension at 6 months postoperatively in the Continuous group was 47 ± 7°, which was significantly greater than in the Single group (43 ± 6°) (P = 0.02). The postoperative strength of the external rotator at 6 months in the Continuous group was 95 ± 33 N, significantly greater than in the Single group (78 ± 28 N) (P = 0.01). There was no significant difference in UCLA score at any time. Conclusion: The continuous interscalene block with ultrasound guidance in ARCR effectively relieved pain. The recovery of ROM for extension and the strength of the external rotator was better in the Continuous group.