Spinal Accessory to Suprascapular Nerve Transfer in Traumatic Brachial Plexus Injury: A Comparative Study of Shoulder Recovery Outcomes in the Anterior versus Posterior Approach and Surgeons' Preference.

BACKGROUND: Conventionally, neural transfer of the spinal accessory nerve to the suprascapular nerve for shoulder abduction in traumatic brachial plexus injury is performed via the anterior approach. However, important advantages of the posterior approach have made it an alternative option, such as the proximity of neural coaptation to the muscle to be reinnervated and negating the effects of a second injury to the suprascapular nerve. METHODS: Retrospective data was collected from 30 patients with brachial plexus injury who underwent spinal accessory nerve to suprascapular nerve transfer over 4 years. There were 15 patients in the anterior-approach group (group A) and 15 in the posterior-approach group (group B). Functional outcome at the shoulder was measured as muscle power and active range of motion at 18 months, and data on patients' satisfaction levels and surgeons' perceptions was also collected. RESULTS: No statistical difference was found in the muscle strength achieved in the 2 groups (P = 0.34), but significant recovery was found in the external rotation achieved by group B (P = 0.02). Statistical difference was insignificant in the 2 groups' active range of motion during abduction and external rotation. The satisfaction index of patients was 86.7% in group B as compared to 68% in group A. Surgeons' perspective showed a faster speed of suprascapular nerve exploration in the posterior approach, with better visibility of supraspinatus muscle contraction, and overall surgeons preferred the posterior approach. CONCLUSIONS: External rotation at the shoulder is better via the posterior approach, but no difference in abduction was noted. Patients who underwent the posterior approach were more satisfied with the recovery, and surgeons preferred the posterior approach.

Diagnosis of suprascapular nerve entrapment syndrome based on the infraspinatus muscle cross-sectional area on shoulder MRI.

Suprascapular nerve entrapment (SNE) syndrome is a commonly overlooked cause of shoulder weakness and pain. It frequently causes weakness over the posterior and lateral and posterior aspects of the shoulder, as well as pain of infraspinatus muscles. Therefore, we considered that the infraspinatus muscle cross-sectional area (IMCSA) might be a new morphological parameter to analyze SNE syndrome. We assumed that the IMCSA is an important morphologic parameter in SNE syndrome diagnosis. We acquired infraspinatus muscle data from 10 patients with SNE syndrome and from 10 healthy subjects who had undergone magnetic resonance imaging of the shoulder and who revealed no evidence of SNE syndrome. We analyzed the infraspinatus muscle thickness (IMT) and IMCSA at the shoulder on the imaging of the shoulder using our image analysis program. The IMCSA was measured as the whole infraspinatus muscle cross-sectional area that was most atrophied in the sagittal S-MR images. The IMT was measured as the thickest level of infraspinatus muscle. The mean IMT was 29.17 ±â€…2.81 mm in the healthy subjects and 25.22 ±â€…3.19 mm in the SNE syndrome group. The mean IMCSA was 1321.95 ±â€…175.91 mm2 in the healthy group and 1048.38 ±â€…259.94 mm2 in the SNE syndrome group. SNE syndrome patients had significantly lower IMT (P < .001) and IMCSA (P < .001) than the healthy group. The ROC curve shows that the optimal cutoff point of the IMT was 26.74 mm, with 70.0% sensitivity, 70.0% specificity, and an AUC of 0.83 (95% CI, 0.65-1.00). The best cutoff value of the IMCSA was 1151.02 mm2, with 80.0% sensitivity, 80.0% specificity, and AUC of 0.87 (95% CI, 0.69-1.00). The IMT and IMCSA were both significantly associated with SNE syndrome. And the IMCSA was a highly sensitive diagnostic tool.

Optimising safe margins in shoulder surgeries: a cadaveric study on brachial plexus nerves with anthropometric and movement correlation.

PURPOSE: Shoulder surgeries, vital for diverse pathologies, pose a risk of iatrogenic nerve damage. Existing literature lacks diverse bone landmark-specific nerve position data. The purpose of this study is to address this gap by investigating such relationships. METHOD: This cadaveric study examines axillary, radial and suprascapular nerves' relation with acromion, coracoid and greater tuberosity of the humerus (GT). It also correlates this data with humeral lengths and explores nerve dynamics in relation to arm positions. RESULTS: The mean distance from the axillary nerve to (i) GT was 4.38 cm (range 3.32-5.44, SD 0.53), (ii) acromion was 6.42 cm (range 5.03-7.8, SD 0.694) and (iii) coracoid process was 4.3 cm (range 2.76-5.84, SD 0.769). Abduction brought the nerve closer by 0.36 cm, 0.35 cm and 0.53 cm, respectively. The mean distance from radial nerve to (i) GT was 5.46 cm (range 3.78-7.14, SD 0.839), (ii) acromion was 7.82 cm (range 5.4-10.24, SD 1.21) and (iii) tip of the coracoid process was 6.09 cm (range 4.07-8.11 cm, SD 1.01). The mean distance from the suprascapular nerve to the acromion was 4.2 cm (range 3.1-5.4, SD 0.575). The mean humeral length was noted to be 27.83 cm (range 25.3-30.7, SD 1.13). There was no significant correlation between these distances and humeral lengths. CONCLUSION: It is essential to exercise caution to avoid axillary nerve damage during the abduction manoeuvre, as its distance from the greater tuberosity and tip of the coracoid process has shown a significant reduction. The safe margins, in relation to the length of the humerus and consequently the patient's stature, exhibit no significant variation. In situations where the greater tuberosity (GT) and the border of the acromion are inaccessible due to reasons such as trauma, the tip of the coracoid process can serve as a dependable bone landmark for establishing a secure surgical margin.

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

OBJECTIVES: The primary objective of this study was to compare pain intensity after pulsed radiofrequency (RF) or suprascapular nerve block for the treatment of chronic shoulder pain. The secondary objectives were to compare the shoulder range of motion and supplementary analgesic requirement. METHODS: This randomized and prospective study included 40 patients, with chronic shoulder pain allocated into 2 groups. One group underwent pulsed RF, and the other group was submitted to block (B) of the suprascapular nerve, guided by ultrasound. They were assessed for 12 weeks regarding pain intensity, the need for analgesia supplementation, and shoulder range of motion. Side effects were recorded. RESULTS: Pain intensity on movement was lower in the RF group after 2, 4, and 8 weeks. At rest, pain intensity was lower in group RF than in group B after 12 weeks. Pain intensity was lower than before the procedure at all times evaluated, in both groups. There was no difference between groups in the range of motion. There was a need for tramadol supplementation in 1 patient in group RF and 2 in group B. Adverse effects observed were local pain (RF: 1), hematoma (RF: 1; B: 1), and lipothymia (B: 2). DISCUSSION: Pulsed RF on the suprascapular nerve promoted an analgesic effect for 12 weeks. Regarding the intensity of pain on movement and at rest, there was a trend toward a better effect with RF than with nerve blockage treatment. In both groups, there was a reduction in pain intensity without serious adverse effects.

A Randomised Control Trial Comparing the Outcomes of Anterior with Posterior Approach for Transfer of Spinal Accessory Nerve to Suprascapular Nerve in Brachial Plexus Injuries.

Background: In brachial plexus surgery, a key focus is restoring shoulder abduction through spinal accessory nerve (SAN) to suprascapular nerve (SSN) transfer using either the anterior or posterior approach. However, no published randomised control trials have directly compared their outcomes to date. Therefore, our study aims to assess motor outcomes for both approaches. Methods: This study comprises two groups of patients. Group A: anterior approach (29 patients), Group B: Posterior approach (29 patients). Patients were allocated to both groups using selective randomisation with the sealed envelope technique. Functional outcome was assessed by grading the muscle power of shoulder abductors using the British Medical Research Council (MRC) scale. Results: Five patients who were operated on by posterior approach had ossified superior transverse suprascapular ligament. In these cases, the approach was changed from posterior to anterior to avoid injury to SSN. Due to this reason, the treatment analysis was done considering the distribution as: Group A: 34, Group B: 24. The mean duration of appearance of first clinical sign of shoulder abduction was 8.16 months in Group A, whereas in Group B, it was 6.85 months, which was significantly earlier (p < 0.05). At the 18-month follow-up, both intention-to-treat analysis and as-treated analysis were performed, and there was no statistical difference in the outcome of shoulder abduction between the approaches for SAN to SSN nerve transfer. Conclusions: Our study found no significant difference in the restoration of shoulder abduction power between both approaches; therefore, either approach can be used for patients presenting early for surgery. Since the appearance of first clinical sign of recovery is earlier in posterior approach, therefore, it can be preferred for cases presenting at a later stage. Also, the choice of approach is guided on a case to case basis depending on clavicular fractures and surgeon preference to the approach. Level of Evidence: Level II (Therapeutic).

The Median Effective Volume of 0.375% Ropivacaine for Ultrasound-guided Anterior Suprascapular Nerve Block in Arthroscopic Shoulder Surgery.

BACKGROUND: The suprascapular nerve (SSN) is an important nerve that contributes to shoulder joint sensation and movement. The anterior suprascapular nerve block (aSSNB) has the potential for noninferior analgesic effect compared with the interscalene block while preserving respiratory function. This study investigated the median effective volume (MEV) of 0.375% ropivacaine in aSSNB for analgesic effect among patients undergoing arthroscopic shoulder surgery. OBJECTIVES: Our primary objective was the MEV. The secondary objectives included the 24 hour sufentanil consumption, 24 hour patient-controlled analgesia (PCA) presses, and incidences of diaphragm impairment. STUDY DESIGN: Prospective registered (ChiCTR2300070129), single-armed, volume-finding study. SETTING: This study was conducted in a tertiary, single center. METHODS: There were 23 patients who completed the study. Using an up-and-down process, patients enrolled in the study received different volumes of 0.375% ropivacaine for an aSSNB adjusted based on the success or failure of the previous patient in the study's block by increasing or decreasing the volume by 3 mL. The first patient received 15 mL of 0.375% ropivacaine. The nerve blocks were evaluated by the sensory score of the C5 and C6 dermatomes. RESULTS: MEV50 (50% of the patients) was 6 mL (95% CI, 5.78 - 6.78 mL), and MEV95 (95% of the patients) was 13.88 mL (95% CI, 13.37 - 14.87 mL). There was no significant difference in the PCA presses, 24 hour sufentanil consumption, and incidences of diaphragm impairments between successful and unsuccessful blocks. LIMITATIONS: Our study focused on the analgesic effect rather than hemi-diaphragmatic paralysis with 0.375% ropivacaine for an aSSNB. The study also did not test varying ropivacaine concentrations while keeping the volume constant. Further investigation with varying concentrations and a larger sample size is indicated to address the optimal volume and concentration to balance analgesia and diaphragm function. CONCLUSIONS: To produce effective analgesic effect, the MEV50 is 6 mL, and the MEV95 is 13.88 mL in patients undergoing arthroscopic shoulder surgery who receive an aSSNB using 0.375% ropivacaine for analgesia.

Shoulder function after neck dissection with level IIb preservation: a prospective observational study.

BACKGROUND: Shoulder syndrome can be reduced by preserving the spinal accessory nerve (SAN). However, it is unclear whether performing level IIb preservation will decrease the risk of SAN injury and shoulder syndrome. AIMS/OBJECTIVES: We investigated whether neck dissection with level IIb preservation can reduce shoulder dysfunction and postoperative quality of life (QOL) in head and neck cancer patients. MATERIAL AND METHODS: This prospective observational study enrolled patients who underwent neck dissection from 2011 to 2014. Patients were divided into three groups (level IIb preservation group [group 1], IIb dissection group [group 2], and IIb and V dissection group [group 3]). Postoperative shoulder function and QOL were evaluated among the three groups. RESULTS: There were a total of 35 neck sides in three groups, with nine neck sides in group 1, 16 neck sides in group 2, and 10 neck sides in group 3. Although the results showed less shoulder dysfunction in group 1 at early postoperative period. The QOL in group 1 was preserved in the early postoperative period. CONCLUSIONS AND SIGNIFICANCE: Neck dissection with level IIb preservation may help reduce shoulder syndrome and maintain QOL in the early postoperative period.

Anterior approach to suprascapular nerve block combined with axillary nerve block for shoulder arthroplasty.

Arthroscopic shoulder operations are associated with postoperative pain, which can lead to chronic pain if not treated effectively. The classic posterior approach for the suprascapular nerve is associated with higher technical failures, and it is a more painful procedure for the patients. We report a case of a 72-year-old male patient who underwent right shoulder arthroplasty. We performed ultrasound-guided suprascapular nerve block with an anterior approach, combined with an axillary nerve block, and provided effective analgesia.

[Relevance of Early Structured Diagnosis to Successful Nerve Reconstruction: A Case Report of an Alpine Professional Skier with an Axillary Nerve Injury]. / Relevanz früher strukturierter Diagnostik zur erfolgreichen Nervenrekonstruktion: Ein Fallbericht bei Nervus axillaris ­ Verletzung einer alpinen Profi-Skisportlerin.

Among high-speed sports, an increased number of high-speed injuries have been observed in alpine downhill racing. We report the case of a young professional ski racer who sustained a shoulder dislocation with an avulsion of the axillary nerve during a World Cup race. After initial treatment was provided for the shoulder dislocation, the patient was left with abduction weakness and a sensory deficit in the region of the deltoid muscle. She underwent electrophysiological and clinical examinations and visited our centre with delay. We immediately performed surgical treatment with a nerve transfer and nerve transplantation. After only 11 months following her fall, she was able to resume her training program. This case report shows the importance of early diagnostic investigation, a visit to a centre of plastic surgery and the good outcome after surgical treatment in patients with peripheral nerve injuries.

Safe zone of supraclavicular nerve during clavicle fixation and its anatomical variations, a cadaveric study.

BACKGROUND: Supraclavicular nerve injury is usually at risk during clavicular fracture fixation. This study aimed to examine the anatomical features and estimate the precise location of supraclavicular nerve branches related to adjacent structural landmarks and to evaluate the differences between sex and side. To highlight the clinical purposes and surgical relevance, this study attempted to define a surgical safe zone that would probably protect the supraclavicular nerve during clavicle fixation. METHOD: A total of 64 shoulders obtained from 15 female and 17 male adult cadavers were examined, identifying the branching patterns of the supraclavicular nerve, measuring the clavicle length and the course of the supraclavicular nerve referring to the sternoclavicular (SC) and acromioclavicular (AC) joint. Data were categorized by sex and side, and their differences were evaluated using Student T-Test and Mann-Whitney U Test. Clinically relevant predictable safe zones were also statistically analyzed. RESULT: The results revealed 7 branching patterns of the supraclavicular nerve. The medial and lateral nerve branches formed a shared trunk, and the medial nerve branches separated to form the intermediate branch, i.e., the most frequent pattern (67.19%). The safe zones were determined to be 6.1 mm among both sexes of the SC joint medially, and 0.7 mm among females and 0 mm among males of the AC joint laterally. Surgical incisions between 29.3 to 51.2% and 60.5 to 79.7% of the clavicle length from the SC joint were the safe zones at the midclavicular shaft among both sexes. CONCLUSION: The findings of this study have provided new insights into the anatomy of the supraclavicular nerve and its variations. It has been revealed that the terminal branches of the nerve consistently pass over the clavicle in a predictable pattern, emphasizing the importance of considering the supraclavicular nerve's safe zones during clinically relevant surgeries. Nevertheless, due to individual anatomical variations, meticulous dissection between these safe zones is necessary to avoid iatrogenic nerve injury among patients. LEVEL OF EVIDENCE: Basic Science Study, Anatomic Study.

Successful Glenohumeral Shoulder Reduction With Combined Suprascapular and Axillary Nerve Block.

BACKGROUND: Anterior glenohumeral dislocation is a common injury seen in the emergency department (ED) that sometimes requires procedural sedation for manual reduction. When compared with procedural sedation for dislocation reductions, peripheral nerve blocks provide similar patient satisfaction scores but have shorter ED length of stays. In this case report, we describe the first addition of an ultrasound-guided axillary nerve block to a suprascapular nerve block for reduction of an anterior shoulder dislocation in the ED. CASE REPORT: A 34-year-old man presented to the ED with an acute left shoulder dislocation. The patient was a fit rock climber with developed muscular build and tone. An attempt to reduce the shoulder with peripheral analgesia was unsuccessful. A combined suprascapular and axillary nerve block was performed with 0.5% bupivacaine, allowing appropriate relaxation of the patient's musculature while providing excellent pain control. The shoulder was then successfully reduced without procedural sedation. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Procedural sedation for reduction of anterior shoulder dislocations is time consuming, resource intensive, and can be risky in some populations. The addition of an axillary nerve block to a suprascapular nerve block allows for more complete muscle relaxation to successfully reduce a shoulder dislocation without procedural sedation.

Preganglionic Injury of C8 Nerve Root Secondary to Shoulder Disloca tion: Diagnosis based on MRI Findings.

INTRODUCTION: Traumatic spinal root injury caused by shoulder dislocation may involve the brachial plexus or, in some cases, a single nerve. The degree of severity of the injury depends on many patient-specific factors as well as the mechanism of injury. It is essential to suspect this type of lesion by means of a thorough physical examination in order to have better patient outcomes. CASE PRESENTATION: We presented the subtle magnetic resonance imaging (MRI) findings in a 35-yearold male with left shoulder trauma and dislocation after falling off a bicycle. He complained of decreased muscle strength and sensitivity in the C8 dermatome. Atrophy of the hypothenar region and flexion deformity of the 4th and 5th digits were noted. Magnetic resonance imaging findings were consistent with a partial preganglionic C8 motor root lesion. We found T2 increased signal intensity and thinning of the intradural segment of the C8 motor nerve root and low signal in the sequence of a multi- echo gradient recalled echo (GRE). CONCLUSION: MRI is a noninvasive tool that allows a detailed anatomical characterization of the nerves. In brachial plexus injuries, the use of the GRE sequence is useful to identify the lesions, even if they are subtle; however, some lesions may go unnoticed. It is important to note that these patients require an interdisciplinary group to reach a correct diagnosis, which is vital to establish the appropriate treatment and follow-up.

Shoulder Arthrodesis for Traumatic Brachial Plexus Injuries: Functional Outcomes and Complications.

BACKGROUND: The external rotation and abduction of shoulder are considered one of the priorities of reconstruction in brachial plexus injury. The aim of this study was to evaluate the functional results and complications of shoulder arthrodesis in patients with brachial plexus injury to better comprehend the benefits of this procedure. METHODS: Between 2015 and 2019, 15 shoulder arthrodesis were performed in patients with long-standing brachial plexus injury. The main indication for arthrodesis was absent or poor recovery of shoulder abduction and external rotation. Patients presented different levels of injury. Shoulder measurements of active abduction and external rotation were made based on image records of the patients. A long 4.5-mm reconstruction plate was fit along the scapular spine, acromion, and lateral proximal third of the humerus. Structured bone graft was fit into the subacromial space. RESULTS: The mean preoperative abduction was 16°, and the mean postoperative abduction was 42°. The mean preoperative external rotation was -59°, and the mean postoperative external rotation was -13°. The mean increase in abduction and external rotation was 25° and 45°, respectively. Bone union was achieved in all cases at an average time of 5.23 months. We experienced humeral fractures in 26.66% of the cases, which were all successfully treated nonoperatively. CONCLUSIONS: Shoulder arthrodesis is a rewarding procedure for patients with brachial plexus injuries. A marked improvement in the upper limb positioning was observed in all patients. It should be considered as the main therapeutic option in cases where nerve reconstruction is no longer possible.

Nerve Transfer Is Superior to Nerve Grafting for Suprascapular Nerve Reconstruction in Obstetrical Brachial Plexus Birth Injury: A Meta-Analysis.

BACKGROUND: Restoration of shoulder function in obstetrical brachial plexus injury is paramount. There remains debate as to the optimal method of upper trunk reconstruction. The purpose of this study was to test the hypothesis that spinal accessory nerve to suprascapular nerve transfer leads to improved shoulder external rotation relative to sural nerve grafting. METHODS: A systematic review of Medline, EMBASE, EBSCO CINAHL, SCOPUS, Cochrane Library, and TRIP Pro from inception was conducted. Our primary outcome was shoulder external rotation. RESULTS: Four studies were included. Nerve transfer was associated with greater shoulder external rotation relative to nerve grafting (mean difference: 0.82 AMS 95% confidence interval [CI]: 0.27-1.36, P < .005). Patients undergoing nerve grafting were more likely to undergo a secondary shoulder stabilizing procedure (odds ratio [OR]: 1.27, 95% CI: 0.8376-1.9268). CONCLUSION: In obstetrical brachial plexus injury, nerve transfer is associated with improved shoulder external rotation and a lower rate of secondary shoulder surgery. LEVEL OF EVIDENCE: Level III; Therapeutic.

Elevated Body Mass Index Negatively Impacts Recovery of Shoulder Abduction Strength in Triceps Motor Branch to Axillary Nerve Transfers.

BACKGROUND: The purpose of this work was to evaluate the clinical outcomes of triceps motor branch to axillary nerve transfers and to identify prognostic factors which may influence these outcomes. METHODS: A retrospective cohort included all patients who underwent a triceps motor branch to axillary nerve transfer (2010-2019) with at least 12 months of follow-up. The primary outcome measure was shoulder abduction strength assessed with British Medical Research Council (MRC) grade. RESULTS: Ten patients were included with a mean follow-up of 19.1 (SD 5.9) months. Compared with preoperative MRC shoulder abduction strength (0.2 SD 0.4), patients significantly improved postoperatively (2.8 SD 1.6; P = .005). Increased body mass index (BMI) was significantly associated with worse postoperative MRC (P = .014). CONCLUSION: Triceps motor branch to axillary nerve transfer is a beneficial procedure for restoring shoulder function in patients presenting with either isolated axillary nerve or brachial plexus pathology. Patients with elevated BMI may not have as robust strength recovery and should be counseled carefully regarding prognosis.

Is there any difference between anterior and posterior approach for the spinal accessory to suprascapular nerve transfer? A systematic review and meta-analysis.

Dual nerve transfer of the spinal accessory nerve to the suprascapular nerve (SAN-SSN) and the radial nerve to the axillary nerve is considered to be the most feasible method of restoration of shoulder abduction in brachial plexus injuries. Supraspinatus muscle plays an important role in the initiation of abduction and its functional restoration is crucial for shoulder movements. There are two possible approaches for the SAN-SSN transfer: the more conventional anterior approach and the posterior approach in the area of scapular spine, which allows more distal neurotization. Although the dual nerve transfer is a widely used method, it is unclear which approach for the SAN-SSN transfer results in better outcomes. We conducted a search of English literature from January 2001 to December 2021 using the PRISMA guidelines. Twelve studies with a total 142 patients met our inclusion criteria. Patients were divided into two groups depending on the approach used: Group A included patients who underwent the anterior approach, and Group B included patients who underwent the posterior approach. Abduction strength using the Medical Research Scale (MRC) and range of motion (ROM) were assessed. The average MRC grade was 3.57 ± 1.08 in Group A and 4.0 ± 0.65 (p = 0.65) in Group B. The average ROM was 114.6 ± 36.7 degrees in Group A and 103.4 ± 37.2 degrees in Group B (p = 0.247). In conclusion, we did not find statistically significant differences between SAN-SSN transfers performed from the anterior or posterior approach in patients undergoing dual neurotization technique for restoration of shoulder abduction.

An alternative approach for blocking the superior trunk of the brachial plexus evaluated by a single arm clinical trial

Abstract Background Interscalene brachial plexus block is associated with phrenic nerve paralysis. The objective of this study was to evaluate an alternative approach to interscalene brachial plexus blocks in terms of efficacy, grade of motor and sensory blockade, and phrenic nerve blockade. Methods The study was prospective and interventional. The ten living patients studied were 18 to 65 years old, ASA physical status I or II, and submitted to correction of rotator cuff injury. A superior trunk blockade was performed at the superior trunk below the omohyoid muscle, without blocking the phrenic nerve. The needle was advanced below the prevertebral layer until contacting the superior trunk. In order to guarantee the correct positioning of the needle tip, an intracluster pattern of the spread was visualized. The block was performed with 5 mL of 0.5% bupivacaine in ten patients. In the six cadavers, 5 mL of methylene blue was injected. Diaphragmatic excursion was assessed by ultrasonography of the ipsilateral hemidiaphragm. In three patients, pulmonary ventilation was evaluated with impedance tomography. Pain scores and analgesic consumption were assessed in the recovery room for 6 hours after the blockade. Results In the six cadavers, methylene blue didn't reach the phrenic nerve. Ten patients underwent arthroscopic surgery, and no clinically phrenic nerve paralysis was observed. No patient reported pain during the first 6 hours. Conclusions This study suggests that this new superior trunk approach to block the superior trunk may be an alternative technique to promote analgesia for shoulder surgery in patients with impaired respiratory function.

An alternative approach for blocking the superior trunk of the brachial plexus evaluated by a single arm clinical trial.

BACKGROUND: Interscalene brachial plexus block is associated with phrenic nerve paralysis. The objective of this study was to evaluate an alternative approach to interscalene brachial plexus blocks in terms of efficacy, grade of motor and sensory blockade, and phrenic nerve blockade. METHODS: The study was prospective and interventional. The ten living patients studied were 18 to 65 years old, ASA physical status I or II, and submitted to correction of rotator cuff injury. A superior trunk blockade was performed at the superior trunk below the omohyoid muscle, without blocking the phrenic nerve. The needle was advanced below the prevertebral layer until contacting the superior trunk. In order to guarantee the correct positioning of the needle tip, an intracluster pattern of the spread was visualized. The block was performed with 5.ßmL of 0.5% bupivacaine in ten patients. In the six cadavers, 5.ßmL of methylene blue was injected. Diaphragmatic excursion was assessed by ultrasonography of the ipsilateral hemidiaphragm. In three patients, pulmonary ventilation was evaluated with impedance tomography. Pain scores and analgesic consumption were assessed in the recovery room for 6.ßhours after the blockade. RESULTS: In the six cadavers, methylene blue didn...t reach the phrenic nerve. Ten patients underwent arthroscopic surgery, and no clinically phrenic nerve paralysis was observed. No patient reported pain during the first 6.ßhours. CONCLUSIONS: This study suggests that this new superior trunk approach to block the superior trunk may be an alternative technique to promote analgesia for shoulder surgery in patients with impaired respiratory function.