Continuous Interscalene Brachial Plexus Block Research Articles

Single-bolus injection of local anesthetic, with or without continuous infusion, for interscalene brachial plexus block in the setting of multimodal analgesia: a randomized controlled unblinded trial

IntroductionPrevious trials favored a continuous interscalene brachial plexus block over a single injection for major shoulder surgery. However, these trials did not administer a multimodal analgesic regimen. This randomized, controlled...

Incidence of Hemidiaphragmatic Paralysis After Ultrasound Guided Low Dose Interscalene Brachial Plexus Block

Background and Aims: Hemidiaphragmatic paralysis is a complication of single shot and continuous interscalene brachial plexus block that can be minimised by ultrasound guided extra fascial catheter placements and by limiting the amount of local anaesthetic administered. In this study, we report incidence of hemidiaphragmatic paralysis with patient-controlled infusion of low volume of ropivacaine after ultrasound guided low dose interscalene brachial plexus block (LD-ISB). Methods: Patients aged 18-65 years undergoing surgery for shoulder dislocation or proximal humerus fracture were recruited and administered general anaesthesia. Before extubation ultrasound guided LD-ISB (10 ml of 0.5% ropivacaine) was administered and a catheter tunneled so that patient controlled interscalene analgesia (PCIA) could be given with low volume ropivacaine. PCIA was initiated after four hours in the post operative recovery to deliver background infusion of 2 ml/h, bolus of 5ml (0.2% of ropivacaine) with lockout interval of 30 minutes for a total duration of 24 hours. Incidence of hemidiaphragmatic paralysis was recorded at extubation using M-mode ultrasonography. Before start of PCIA i.e. at 4 hours and after start of PCIA i.e. 6,12 and 24 h after extubation. Results: PCIA after LD-ISB was administered to 29 patients. Subsequently, two patients were excluded due to catheter dislodgement. The incidence of complete and partial paresis of diaphragm after extubation was 85% and 3.7% with LD-ISB respectively but was resolved before start of PCIA i.e., at 4 hours. Thus, at time of commencement of PCIA all patients had normal diaphragmatic excursions and subsequently at 6,12 and 24 h no paresis/paralysis was reported in patients administered only the background infusion or an additional single bolus dose of ropivacaine with the background infusion. Partial paresis was noted in all patients in which two bolus doses/h were administered. All patients with paresis had diaphragmatic excursion normalised in the next recording made at 4 hours and no complication was reported in any patient. VAS (Visual Analog Scale) was below 3 at all time points. Conclusion: Partial/complete paresis after a single shot injection of 10 ml of 0.5% ropivacaine resolves in 4 hours. PCIA initiated after it for subsequent 20 hours with a single bolus dose of 5ml of 0.2% ropivacaine and background infusion at 2 ml/h does not cause phrenic paresis. Partial paresis is reported with two bolus doses/h, but it is clinically asymptomatic. Thus, the above dose regimes are safe and effective in managing post-operative pain. Keywords: Interscalene block, Diaphragmatic paresis, Ropivacaine, continuous infusion, Analgesic efficacy

A comparison of the continuous supraclavicular brachial plexus block using the proximal longitudinal oblique approach and the interscalene brachial plexus block for arthroscopic shoulder surgery: A randomised, controlled, double-blind trial.

Continuous interscalene brachial plexus block (ISB) is widely used for arthroscopic shoulder surgery, but the incidence of hemidiaphragmatic paresis (HDP) has been reported to reach 100%. Several methods, including injections distal to the C5-C6 nerve roots, have been attempted to reduce the HDP incidence. However, catheter placement distal to the C5-C6 nerve roots interferes with the surgical site. Our primary objective was to describe a new technique, the supraclavicular brachial plexus block (SCB), using the proximal longitudinal oblique approach (PLO-SCB), which can facilitate catheter placement and, when compared with ISB, to test whether this would provide noninferior analgesia and spare the phrenic nerve. Prospective, randomised, double-blind study. Operating rooms, postanaesthesia care unit, and wards. Seventy-six patients aged 20 to 80 years scheduled for arthroscopic shoulder surgery. Patients were randomly assigned to the continuous PLO-SCB ( n = 40) or the continuous ISB ( n = 40) groups. All patients received an initial low-volume single-injection (5 ml 0.75% ropivacaine) followed by a patient-controlled infusion of 0.15% ropivacaine. The primary outcomes were the incidence of HDP and pain scores. Secondary outcomes were respiratory function, postoperative analgesic consumption, sensory and motor function, and complications. The HDP incidence was significantly lower in the PLO-SCB group than in the ISB group at 30 min after block injection: 0% (0 of 38 patients) and 73.7% (28 of 38 patients), respectively ( P < 0.001). Similarly, at 24 h after surgery, the incidences were 23.7% (9 of 38 patients) and 47.4% (18 of 38 patients) in the PLO-SCB and ISB groups, respectively ( P = 0.002). Median [IQR] NRS pain scores at rest measured after surgery in the ISB and PLO-SCB groups were similar: immediately after surgery, 1 [0 to 2] vs. 1 [0 to 1], P = 0.06); at 30 min, 2 [0.25 to 2] vs. 1 [0 to 2], P = 0.065); and at 24 h 2 [0.25 to 3] vs. 1 [0 to 3], P = 0.47, respectively. For major shoulder surgery, compared with continuous ISB, continuous PLO-SCB was more sparing of diaphragmatic and respiratory function while providing noninferior analgesia. Catheter placement via the PLO approach is feasible without interfering with the surgical field. Registered by the Clinical Trial Registry of Korea (Seoul, Korea; KCT0004759, http: cris.nih.go.kr, principal investigator: Hyungtae Kim).

Rate of occurrence of respiratory complications in patients who undergo shoulder arthroplasty with a continuous interscalene brachial plexus block and associated risk factors

IntroductionContinuous interscalene nerve block techniques are an effective form of targeted non-opioid postoperative analgesia for shoulder arthroplasty patients. One of the limiting risks, however, is potential phrenic nerve blockade with...

Comparison of Continuous and Programmed Intermittent Bolus Infusion of 0.2% Ropivacaine after Ultrasound-Guided Continuous Interscalene Brachial Plexus Block in Arthroscopic Shoulder Surgery.

Despite the clinical effectiveness of the programmed intermittent bolus (PIB) method for epidural analgesia, evidence for this method in continuous interscalene brachial plexus block (CIBPB) is unclear. This study aimed to investigate the pain relief effect after arthroscopic shoulder surgery according to the administration method by comparing the PIB and continuous infusion methods among the administration methods of local anesthetics. Sixty-four patients aged >19 years scheduled for elective arthroscopic shoulder surgery were enrolled and divided into two groups. Ultrasound-guided CIBPB was performed to control postoperative pain. The infusion pump was programmed so that 0.2% ropivacaine was continuously injected at 1.1 mL/h in group A, whereas in group B, 0.1 mL/h was continuously injected and 4 mL was periodically injected at 4 h intervals. In both groups, a further infusion of 4 mL of 0.2% ropivacaine was administered if the patient requested additional analgesia, and the lockout time was set at 30 min. Postoperative pain quality was assessed using a visual analog scale (VAS), and the incidence of patients requiring additional analgesics, motor blockade using a modified Bromage scale (MBS), and consumed doses of local anesthetic were assessed. The VAS and incidence of rescue analgesics were performed when the patient could communicate voluntarily after admission to the post-anesthetic care unit, and at 24 and 48 h after surgery showed no significant difference between the two groups. The MBS at 24 h after surgery was significantly higher in group B (p = 0.038). In the comparison of consumed doses of local anesthetic, group B had a significantly higher bolus injection dose (p = 0.047) and frequency of bolus use in the 24 h after surgery (p = 0.034). The PIB method in CIBPB after arthroscopic shoulder surgery provided a similar analgesic effect, with a higher bolus injection dose of local anesthetic and increased motor blockade than the continuous infusion method.

Initiation Timing of Continuous Interscalene Brachial Plexus Blocks in Patients Undergoing Shoulder Arthroplasty: A Retrospective Before-and-After Study.

A continuous interscalene brachial plexus block (CIBPB) is usually administered before surgery in awake patients. However, the use of CIBPB before surgery could hinder the identification of nerve injuries after total shoulder arthroplasty (TSA). This study aimed to compare the analgesic effects of preoperatively and postoperatively initiated CIBPBs in patients undergoing TSA. The medical records of patients who underwent TSA between January 2016 and August 2020 were retrospectively reviewed. The following analgesic phases were used: intravenous (IV) patient-controlled analgesia (PCA) phase (IV PCA group, n = 40), preoperative block phase (PreBlock group, n = 44), and postoperative block phase (PostBlock group, n = 33). The postoperative initiation of CIBPB after a neurologic exam provided better analgesia than IV PCA and had no differences with the preoperative initiation of CIBPB, except for the worst pain at the postanesthetic care unit. Opioid consumption was significantly greater in the IV PCA group, but there were no differences between the PreBlock and PostBlock groups on operation day after the transfer to the general ward. The initiation of CIBPB after a patient’s emergence from general anesthesia had comparable analgesic efficacy with preoperative CIBPB but offered the chance of a postoperative neurologic exam.

Effects of Different 0.2% Ropivacaine Infusion Regimens for Continuous Interscalene Brachial Plexus Block on Postoperative Analgesia and Respiratory Function After Shoulder Arthroscopic Surgery: A Randomized Clinical Trial.

ObjectiveContinuous interscalene brachial plexus block (cIBPB) is an effective perioperative analgesic therapy for shoulder arthroscopic surgery (SAS) patients. This trial aimed to compare the effect of different cIBPB infusion methods on postoperative analgesia and respiratory function in patients undergoing SAS.MethodsAfter SAS, 88 patients were randomly assigned to four groups. Through interscalene catheter, all the patients received an initial dose of 10 mL 0.2% ropivacaine. The CI group received 0.2% ropivacaine 4 mL/h, and the PIBI1, PIBI2, and PIBI3 groups received intermittent 0.2% ropivacaine boluses at 4 mL/h, 8 mL/2 h, and 12 mL/3 h, respectively. The patients could also use a patient-controlled analgesia (PCA) pump to self-inject a tramadol bolus each time he/she felt pain. The primary outcome was the cumulative tramadol consumption over the 48 h after surgery. Secondary outcome measures included PCA frequency, pain (visual analogue scale, VAS) score, patient satisfaction, diaphragmatic excursion, pulmonary function, and adverse events.ResultsThe cumulative tramadol consumption and PCA frequency over the 48 h after surgery in groups PIBI2 and PIBI3 were lower than in both the CI and PIBI1 groups (p<0.001). The VAS scores (at rest and on movement) in groups PIBI2 and PIBI3 were lower than those in the CI and PIBI1 groups at 8 and 12 h after surgery (all p<0.001). Patient satisfaction scores were significantly higher in the PIBI2 group than in the other three groups (all p<0.001). Diaphragmatic excursion was significantly decreased in the PIBI3 group compared to the other three groups (p<0.05). The incidence of adverse events over the 48 h after surgery was significantly higher in the PIBI3 group compared to the other three groups (p<0.001).ConclusionProgrammed intermittent bolus infusion with 0.2% ropivacaine 8 mL/2 h for cIBPB can achieve lower tramadol consumption, along with better analgesia after surgery, lower reduction in diaphragmatic excursion, lower incidence of adverse events, and higher patient satisfaction.

Postoperative Respiratory Failure Due to Pulmonary Embolism and Phrenic Nerve Hemiparalysis during Continuous Interscalene Brachial Plexus Block after Shoulder Surgery： A Case Report

Postoperative Respiratory Failure Due to Pulmonary Embolism and Phrenic Nerve Hemiparalysis during Continuous Interscalene Brachial Plexus Block after Shoulder Surgery： A Case Report

Distance of catheter tip dislocation in continuous interscalene brachial plexus block.

Distance of catheter tip dislocation in continuous interscalene brachial plexus block.

Incidence and effects of postoperative migration of interscalene catheter tips placed using ultrasound-guided anterior and posterior approaches.

Continuous interscalene brachial plexus block (CISB) provides analgesia after shoulder surgery. However, even a catheter securely fixed at the insertion site may be susceptible to migration, precluding the block from working consistently. We examined to see if catheter tip migration would occur with no catheter-at-skin change after anterior and posterior approaches to CISB in patients undergoing shoulder surgery, and compared the incidence rate and pain scores between approaches and between catheters with and without tip migration, respectively. Patients were randomly assigned to receive CISB using either anterior or posterior approach. Catheter tip was observed using a cross-sectional view. The rates of catheter tip migration with no catheter-at-skin change at 24h after the two approaches were calculated and compared, and pain scores were compared between catheters with and without tip migration after each approach. Fifty-four patients were analyzed. Catheter tip migration occurred at 24h at a similar rate after both approaches (anterior approach 40.7% versus posterior approach 33.3%, p = 0.78). Worst pain score was significantly higher for 24h in patients whose catheter tip had migrated as compared with those whose catheter had not migrated after anterior (median [IQR] 53 [42-73] versus 18 [0-50], p = 0.003) and posterior approaches (median [IQR] 63 [57-81] versus 29 [3-47], p < 0.0001). In patients undergoing shoulder surgery, an interscalene catheter tip can migrate after both anterior and posterior approaches at a similar rate, even if the catheter insertion length is not changed. The tip migration does decrease the analgesic effect of CISB.

Following major shoulder surgery, how does continuous interscalene brachial plexus block compare with parenteral analgesia for pain relief?

Following major shoulder surgery, how does continuous interscalene brachial plexus block compare with parenteral analgesia for pain relief?

Severe and persistent nerve palsy after ultrasound-guided continuous interscalene brachial plexus block in a teenager undergoing shoulder surgery: a case report

BackgroundAlthough neurologic sequela is a recognized complication after interscalene brachial plexus block (ISB), there is a paucity of information on how severe and persistent neuropathy occurs and develops.Case presentationA healthy high school soccer goalkeeper was scheduled for an arthroscopic Bankart repair. After continuous ISB for 2 days, sensation in the C5 and C6 areas and motor function did not return. With symptomatic drug treatment for neuropathic pain and rigorous rehabilitation, recovery of sensory loss and muscle weakness were gradually observed around 1 to 2 months after surgery. He returned to sport 1 year after surgery.ConclusionThis report is the first detailed description of a case who incurred severe and persistent nerve injury after continuous ISB yet recovered nearly fully to return to being an athlete. The present case should also underscore the importance of close observation after surgery in cases where a patient receives continuous ISB.

Periarticular multimodal drug injection does not improves early postoperative analgesia compared with continuous interscalene brachial plexus block after arthroscopic rotator cuff repair: A retrospective single-center comparative study

BackgroundAlthough continuous interscalene brachial plexus block (CISBPB) is common method in pain management following arthroscopic rotator cuff repair (ARCR), little is known about the analgesic effects of periarticular multimodal drug injection (PMDI) for ARCR. This retrospective study sought to clarify which technique could provide the best analgesic effect after ARCR. MethodsWe retrospectively reviewed consecutive patients who underwent ARCR performed by the same surgeon at our institution between June 2016 and November 2017. Patients who underwent surgery before January 2017 received CISBPB and those who underwent surgery after February 2017 received PMDI for postoperative pain control. Both treatment groups also received fentanyl by intravenous patient-controlled analgesia (IV-PCA). Postoperative pain was evaluated by visual analog scale (VAS) pain scores at 3, 6, 12, 24, and 48 h and need for IV-PCA at 8, 16, and 24 h. ResultsTwenty-eight patients received CISBPB and 21 received PMDI. According to the VAS scores, the postoperative analgesic effect was significantly better in the CISBPB group during the first 6 h (p < 0.05). Total fentanyl consumption by IV-PCA during the first 8 postoperative h was significantly greater in the PMDI group than in the CISBPB group. ConclusionsPMDI does not improve early postoperative analgesia after ARCR compared with CISBPB. CISBPB had a significantly better analgesic effect in the first 8 h postoperatively. Level of evidenceLevel III.

Reduced hemidiaphragmatic paresis with extrafascial compared with conventional intrafascial tip placement for continuous interscalene brachial plexus block: a randomized, controlled, double-blind trial

BackgroundThe incidence of hemidiaphragmatic paresis with continuous interscalene brachial plexus block (CISB) can approach 100%. We tested the hypothesis that extrafascial placement of the catheter tip reduces the rate of hemidiaphragmatic paresis compared with intrafascial tip placement for CISB while providing effective analgesia. MethodsSeventy patients undergoing elective major shoulder surgery under general anaesthesia were randomized to receive an ultrasound-guided CISB plexus block for analgesia with the catheter tip placed either within (intrafascial group) or immediately outside (extrafascial group) the brachial plexus sheath midway between the levels of C5 and C6. Catheters were bolus dosed with ropivacaine 0.5% 20 ml before surgery, followed by an infusion of ropivacaine 0.2% at 4 ml h−1 for the first 2 days after surgery. The primary outcome was hemidiaphragmatic paresis measured by M-mode ultrasonography on postoperative day (POD) 1. Secondary outcomes included forced vital capacity, forced expiratory volume in 1 s, and rest pain scores. ResultsThe incidence of hemidiaphragmatic paresis on POD 1 was significantly reduced in the extrafascial group {intrafascial, 41% [95% confidence interval (CI) 25–59%]; extrafascial, 15% (95% CI 5–32%); P=0.01}. We were unable to detect a difference between groups in any of the functional respiratory outcomes or in rest pain scores [numerical rating scale (1–10): intrafascial, 3 (95% CI 2–3); extrafascial, 3 (95% CI: 2–4); P=0.93] on POD 1. ConclusionsPlacement of the catheter tip immediately outside of the brachial plexus sheath reduced the incidence of hemidiaphragmatic paresis on POD 1 associated with ultrasound-guided CISB while providing effective analgesia after major shoulder surgery. Our results do not support the routine placement of the catheter tip within the brachial plexus sheath for CISB. Clinical trial registrationNCT02433561.

Continuous Interscalene Brachial Plexus Block for Shoulder Mobilization and Rehabilitation

Continuous Interscalene Brachial Plexus Block for Shoulder Mobilization and Rehabilitation

Postoperative Analgesia in a Prolonged Continuous Interscalene Block Versus Single-Shot Block in Outpatient Arthroscopic Rotator Cuff Repair: A Prospective Randomized Study

To compare the analgesic efficacy of 3-day continuous interscalene brachial plexus block versus a single-shot block for arthroscopic rotator cuff repair. Eighty-five patients scheduled for arthroscopic rotator cuff repair were randomly assigned to either the single-shot group (SSG) or continuous interscalene brachial block group (CG). Patients in the SSG received 2.5mg/kg of 0.5% bupivacaine up to 25mL; the CG received the same dose as a loading dose via catheter followed by an infusion of 0.125% bupivacaine at 5mL/h and a patient-controlled bolus of 5mL hourly for 72hours. Follow-up after discharge was with telephone calls over the next 3days. Pain was measured on a visual analog scale. Also measured were sleep disturbance, number of opioid doses taken, adverse effects, and level of patient satisfaction. The median rest pain scores on the 3days of follow-up measured on a scale of 0 to 10 (with 10 equal to greatest pain) were 0, 0, and 3 in the CG compared with 4, 4, and 3 in the SSG (P < .001) for days 1, 2, and 3, respectively. The median maximum scores were 2, 2, and 4 in the CG compared with 8, 7, and 6 in the SSG (P < .001) for the same time period. A 3-day continuous interscalene brachial plexus block provides better analgesia than a single-shot block. Sleep patterns were better, and less opioid was needed after arthroscopic rotator cuff repair in patients given a continuous plexus block. Level I, prospective randomized study.

An analysis of 1505 consecutive patients receiving continuous interscalene analgesia at home: a multicentre prospective safety study.

Continuous interscalene brachial plexus block has been shown to be the most effective analgesic technique following shoulder surgery; however, its use is uncommon due to logistical and safety concerns related to ambulatory administration. We prospectively studied 1505 consecutive patients undergoing shoulder surgery who received continuous interscalene analgesia at home. Catheter removal was by the patient between postoperative days two and five. There were no major complications although 27% of patients reported mild dyspnoea, 13% hoarseness and 7% dysphagia. Twelve percent sought medical advice and 2% reported technical issues with the pump or tubing. Complications and technical issues were associated with patient age; weight; use of ultrasound or concomitant nerve stimulation as the endpoint for final needle tip position; local anaesthetic placement via the catheter or needle; whether a catheter-related intervention for pain relief was required in the recovery area; and the type of ambulatory pump. We conclude that this study supports the safety of this underused analgesic technique.

Efficacy of Continuous Brachial Plexus Block for Intractable Cancer Pain in a Terminal Patient

We report a case of terminal cancer in which continuous peripheral nerve block provided effective relief for cancer-related pain that was difficult to control with pharmacotherapy. A 70-year-old woman with thyroid cancer, paraplegia due to multiple bone metastases, and cauliflower-like proliferation of skin metastasis on the left upper arm was receiving inpatient palliative care. Intractable pain during treatment of the tumor and when changing body position due to metastatic tumor and pathological fracture of the left humerus was difficult to control with pharmacotherapy. Continuous interscalene brachial plexus block was therefore performed, resulting in effective pain relief over the subsequent 38 days before death. Ultrasound-guided continuous peripheral nerve block can be performed at the bedside in patients in poor general condition who cannot tolerate neuraxial block, and should be considered in cases of terminal cancer patient suffering from intractable pain despite pharmacotherapy.

Infusion Methods for Continuous Interscalene Brachial Plexus Block for Postoperative Pain Control after Arthroscopic Rotator Cuff Repair.

BackgroundInfusion methods during regional analgesia using perineural catheters may influence the quality of postoperative analgesia. This study was conducted to compare the effects of combined or bolus-only infusion of 0.2% ropivacaine on the postoperative analgesia in interscalene brachial plexus block (ISBPB) with perineural catheterization.MethodsPatients scheduled for arthroscopic rotator cuff repair were divided into two groups, one that would receive a combined infusion (group C, n = 32), and one that would receive intermittent infusion (group I, n = 32). A perineural catheter was inserted into the interscalene brachial plexus (ISBP) using ultrasound (US) and nerve stimulation, and 10 ml of 0.2% ropivacaine was administered. After the operation, group C received a continuous infusion of 4 ml/h, and a 4 ml bolus with a lockout interval of 60 min. Group I received only a 4 ml bolus, and the lockout interval was 30 min. Postoperative pain by the numeric rating scale (NRS) and the forearm muscle tone by the manual muscle test (MMT) were checked and evaluated at the following timepoints: preoperative, and postoperative 1, 4, 12, 24, 36, and 48 h. Supplemental opioid requirements, total consumed dose of local anesthetic, and adverse effects were compared between the two groups.ResultsSixty-four patients completed the study and the postoperative values such as operation time, time to discharge, and operation site were comparable. There were no differences in NRS scores and supplemental opioid requirements between the two groups. The MMT scores of group I at 4 and 12 h after surgery were significantly higher than those of group C (P < 0.05). The total consumed dose of local anesthetic was significantly lower in group I than in group C (P < 0.05). The adverse effects were not different between the groups.ConclusionsThe bolus-only administration of 0.2% ropivacaine provided a similar analgesic effect with a lower total volume of local anesthetic and decreased motor weakness compared to combined infusion. Therefore, bolus-only administration is an effective postoperative analgesic method in ISBPB with perineural catheterization after rotator cuff repair.

Analgesic efficacy of two interscalene blocks and one cervical epidural block in arthroscopic rotator cuff repair.

Despite its effectiveness in other surgeries, studies on continuous epidural block in upper-extremity surgery are rare because of technical difficulties and potential complications. This study compared postoperative analgesic efficacy and safety of ultrasound-guided continuous interscalene brachial plexus block (UCISB) and fluoroscopy-guided targeted continuous cervical epidural block (FCCEB) in arthroscopic rotator cuff repair (ARCR). Seventy-five patients were randomly and equally assigned to groups FCCEB (0.2%), UCISB75 (0.75%), and UCISB20 (0.2%) according to the initial ropivacaine dose (8 ml). The background infusion (0.2% ropivacaine at 5 ml/h), bolus (3 ml of 0.2% ropivacaine), and lockout time (20 min) were consistent. Respiratory effects [respiratory discomfort (modified Borg scale), ventilatory function, and hemidiaphragmatic excursion (ultrasound)], analgesic quality [pain severity at rest and motion attempt (VAS-R and -M), number of boluses, analgesic supplements, and sleep disturbance], neurologic effects, procedural discomfort, satisfaction, and adverse effects were evaluated preprocedurally and up to 72 h postoperatively. FCCEB caused less respiratory depression and sensorimotor block, but had less analgesic efficacy than UCISBs (P < 0.05). FCCEB caused nausea, vomiting, and dizziness more frequently (P < 0.05) and had lower patient satisfaction than UCISBs (P < 0.05). UCISB75 can cause severe respiratory distress in patients with lung disorders. Other variables were not significantly different between the groups. UCISB20 may provide superior postoperative analgesia and is the most recommendable postoperative analgesic method in ARCR. Randomized controlled trials, Therapeutic study, Level I.