Suprascapular Nerve Pathology: A Review of the Literature

Suprascapular nerve peripheral nerve stimulation for malignancy-related pain: A case series

Background

Blockade of the suprascapular nerve is an effective diagnostic tool in the workup and potential treatment of shoulder pain. For chronic shoulder pain, peripheral nerve stimulation has been shown to provide significant, sustained pain relief. However, no literature to date has described peripheral nerve stimulation for the treatment of oncologic shoulder pain.

Objectives

We describe two cases of chronic oncologic-related shoulder pain that responded to posterior suprascapular peripheral nerve stimulator placement to facilitate future progress and discussion in the fields of peripheral nerve stimulation and oncology pain.

Methods

Two subjects with chronic shoulder pain underwent ultrasound-guided peripheral nerve stimulation therapy at the suprascapular nerve.

Results

At follow-up visits (30 and 98 days after procedure), both subjects reported greater than 50% pain relief as measured by the numerical rating scale (NRS).

Conclusions

Peripheral nerve stimulator placement at the suprascapular nerve is a feasible procedure to treat oncologic shoulder pain via the described technique. Both subjects experienced clinically significant pain relief and decreased oral analgesic medication intake, and decreased medication-related side effects. This warrants further investigation including large comparative, prospective studies to better assess efficacy and safety of this approach.

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.

Correlation of suprascapular notch morphology with suprascapular nerve palsy: a 3D-computed tomography study

Background

The morphology of the suprascapular (SS) notch is a very important factor in treatment of suprascapular nerve (SSN) palsy. Several studies have reported SS notch morphology in cadavers or using a three-dimensional computed tomography (3D-CT); however, none has reported the distribution of SS notch morphology according to the age group. In addition, the correlation between SS notch morphology and SSN palsy remains unclear. The purposes of this study were to investigate the morphological distribution of the SS notch by age group in a large population and to assess the relationship between SS notch morphology and SSN palsy.

Methods

We studied the 3D-CT images of 1063 shoulders in 1009 patients (mean age, 60.8 years; age range, 14-96 years). There were 53 shoulders with SSN palsy and 1010 shoulders without SSN palsy. Morphology of the SS notch was classified by Rengachary's classification (types I-VI). Shoulders with types I-IV were classified into the nonossified superior transverse scapular ligament (STSL) group (group N) and those with types V and VI into the ossified STSL group (group O).

Results

The Rengachary's classifications of the 1063 shoulders were as follows: type I: n = 113, 10.6%; type II: n = 313, 29.4%; type III: n = 383, 36.0%; type IV: n = 109, 10.3%; type V: n = 107, 10.0%; and type VI: n = 38, 3.6%. Mean age was significantly older in the ossified STSL group, and the age was <40 years for only two shoulders in this group. The Rengachary's classifications of the SSN palsy cases were as follows: type I: 7.5%, II: 24.5%, III: 34.0%, IV: 15.1%, V: 13.2%, and VI: 5.7%. There was no statistical difference in age and sex, Rengachary type, or ossification between SSN palsy and non-SSN palsy cases.

Conclusions

Ossification of the STSL was significantly more common in older patients, which suggests age-related change. In addition, no relation was identified between narrow notch or ossification of the STSL with the onset of SSN palsy.

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.

Recovery of brachial plexus injury after bronchopleural fistula closure surgery based on electrodiagnostic study: A case report and review of literature

BACKGROUND

Axillary thoracotomy and muscle flap are muscle- and nerve-sparing methods among the surgical approaches to bronchopleural fistula (BPF). However, in patients who are vulnerable to a nerve compression injury, nerve injury may occur. In this report, we present a unique case in which the brachial plexus (division level), suprascapular, and long thoracic nerve injury occurred after BPF closure surgery in a patient with ankylosing spondylitis and concomitant multiple joint contractures.

CASE SUMMARY

A 52-year-old man with a history of ankylosing spondylitis with shoulder joint contractures presented with right arm weakness and sensory impairment immediately after axillary thoracotomy and latissimus dorsi muscle flap surgery for BPF closure. During the surgery, the patient was positioned in a lateral decubitus position with the right arm hyper-abducted for approximately 6 h. Magnetic resonance imaging and ultrasound revealed subclavius muscle injury or myositis with brachial plexus (BP) compression and related neuropathy. An electrodiagnostic study confirmed the presence of BP injury involving the whole-division level, long thoracic, and suprascapular nerve injuries. He was treated with medication, physical therapy, and ultrasound-guided injections. Ultrasound-guided steroid injection at the BP, hydrodissection with 5% dextrose water at the BP and suprascapular nerve, and intra-articular steroid and hyaluronidase injection at the glenohumeral joint were performed. On postoperative day 194, the pain and arm weakness were resolved, and a follow-up electrodiagnostic study showed marked improvement.

CONCLUSION

Clinicians should consider the possibilities of multiple nerve injuries in patients with joint contracture, and treat each specific therapeutic target.

Outcomes after minimally invasive and surgical management of suprascapular nerve entrapment: A systematic review

BACKGROUND

The prevalence of suprascapular neuropathy is higher than previously estimated. Recent literature highlights a myriad of treatment options for patients ranging from conservative treatment and minimally invasive options to surgical management. However, there are no comprehensive review articles comparing these treatment modalities.

OBJECTIVE

The purpose of this review article is to summarize the current state of knowledge on suprascapular nerve entrapment and to compare minimally invasive treatments to surgical treatments.

METHODS

The literature search was performed in Mendeley. Search fields were varied redundant. All articles were screened by title and abstract and a preliminary decision to include an article was made. A full-text screening was performed on the selected articles. Any question regarding the inclusion of an article was discussed by 3 authors until an agreement was reached.

RESULTS

Recent studies have further elucidated the pathoanatomy and described several risk factors for entrapment ranging. Four studies met our inclusion criteria regarding peripheral nerve stimulation with good pain and clinical outcomes. Two studies met our inclusion criteria regarding pulsed radiofrequency and showed promising pain and clinical outcomes. One study met our inclusion criteria regarding transcutaneous electrical nerve stimulation and showed good results that were equivalent to pulsed radiofrequency. Surgical treatment has shifted to become nearly all arthroscopic and surgical outcomes remain higher than minimally invasive treatments.

CONCLUSIONS

Many recently elucidated anatomical factors predispose to entrapment. A history of overhead sports or known rotator cuff disease can heighten a clinician's suspicion. Entrapment at the suprascapular notch is more common overall, yet young athletes may be predisposed to isolated spinoglenoid notch entrapment. Pulsed radiofrequency, peripheral nerve stimulation, and transcutaneous electrical nerve stimulation may be effective in treating patients with suprascapular nerve entrapment. Arthroscopic treatment remains the gold-standard in patients with refractory entrapment symptoms.

Eхperience of endoscopic decompression of the suprascapular nerve

Background: Suprascapular nerve neuropathy is a commonly spread pathology, caused by a traction force trauma or compression in the scapular notch area. In the case of a conservative treatment failure, a standard surgical procedure is neurolysis (decompression) of the suprascapular nerve in the scapular notch. This procedure can be done in an open manner or endoscopically. Aims: to evaluate the results of endoscopic decompression of the suprascapular nerve in the scapular notch area at a 6 months follow-up. Methods: We operated 10 patients with the clinical picture of posttraumatic suprascapular nerve neuropathy in the period from 2015 to 2021. The mean age of patients was 52.311.8. All the patients underwent the shoulder joint and subacromial space arthroscopy, and decompression of the suprascapular nerve in the scapular notch area. Results: According to the VAS-scale, the severity of pain syndrome before the surgery was 6 cm, while in 6 months after the surgery it decreased to 2 cm. According to the DASH scale, the dysfunction of the of shoulder joint before the surgery was 70 points, in 6 months after the surgery it decreased to 10 points. The range of motion in the shoulder joint before the surgery was: flexion 15514,4, abduction 14042, external rotation 125,6; 6 months after the surgery we observed: flexion 17415,6, abduction 17514,4, external rotation 489. Conclusion: The obtained results let us characterize the method of endoscopic decompression of the suprascapular nerve as a low-traumatic and effective technique, which promotes restoration of the function of the suprascapular nerve and shoulder joint, and elimination of pain syndrome from the shoulder area.

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.

An anatomical study for the location of suprascapular and spinoglenoid notches using three-dimensional computed tomography images of scapula

Background

The optimal position for creating portals for arthroscopic suprascapular nerve decompression has not been sufficiently verified. Therefore, this study aimed to investigate the anatomical characteristics of the scapula for optimal portal creation using 3-dimensional computed tomography images. The posterolateral corner of the acromion was designated as the starting point for measurements because there is no secondary ossification center present.

Methods

This study included 223 patients (females, 129; males, 94) who underwent computed tomography of the shoulder joint. Three-dimensional images of the scapula were created, and the distance from the posterolateral corner of the acromion to the suprascapular and spinoglenoid notches was measured. Additionally, the correlation coefficient with height and the differences between the female and male groups were investigated.

Results

The distances from the posterolateral corner of the acromion to the suprascapular and spinoglenoid notches were 42.9 ± 4.6 and 31.5 ± 3.6 mm, respectively, and their correlation coefficients with height were 0.12 and 0.067, respectively. There was no significant difference in the distance from the posterolateral corner of the acromion to the suprascapular (42.5 ± 4.1 vs. 43.9 ± 5.1 mm, P = .098) and to the spinoglenoid (31.4 ± 3.3 mm vs. 32.0 ± 3.9 mm, P = .12) notches between the female and male groups.

Conclusion

Regardless of height and sex, the distances from the posterolateral corner of the acromion to the suprascapular and spinoglenoid notches were approximately 43 and 32 mm, respectively. Therefore, creating portals at these locations may be effective for arthroscopic suprascapular nerve decompression.

A Tale of Two Suprascapular Neuropathy Presentations: A Case ReportLearning Point of the Article

Introduction

Supra-scapular nerve (SSN) neuropathy is a rare condition that can cause shoulder dysfunction. Prior literature has identified mass effect, space occupying lesions, trauma, and repetitive overhead activities as possible etiologies.

Cases Presentations

We report two cases of SSN neuropathy; a 21-year-old competitive female volleyball player with traction associated neuropathy and a 45-year-old male with a large paralabral ganglion cyst causing compressive neuropathy.

Conclusion

The following report highlights two different etiologies of SSN neuropathy and reviews the treatment of these conditions. Clinicians should consider SSN neuropathy in patients with unexplained shoulder pain and dysfunction.

Suprascapular Neuropathy in Collegiate Tennis Player: A Case Report

Suprascapular neuropathy can be seen in overhead athletes and should be considered when evaluating an overhead athlete presenting with shoulder pain and/or weakness. The suprascapular nerve innervates the supraspinatus and the infraspinatus, but dynamic entrapment as it passes under the spinoglenoid ligament at the spinoglenoid notch can lead to isolated denervation of the infraspinatus. Specific movements common in tennis cause tensioning and compression of the spinoglenoid ligament and may predispose players to dynamic entrapment at this location. We present a case of an 18-year-old male collegiate tennis player presenting with suprascapular neuropathy causing isolated denervation of the infraspinatus. This case illustrates the consequences of noncompliance with physical therapy and serves as a review of the pathophysiology, evaluation, and treatment of suprascapular neuropathy.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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

Effect of different postures of the scapular girdle and arm on the pressure pain threshold in the infraspinatus muscle

BACKGROUND

Mechanosensitivity changes and trigger points in the infraspinatus muscle are associated with several painful conditions of the upper limb. The aim of this study was to assess the effect of different postures of the upper quadrant on the pressure pain threshold (PPT) of the infraspinatus muscle.

METHODS

This was an observational, cross-sectional study. Fifty-four subjects with and without shoulder pain (Asymptomatic subjects = 27, mean age 26.9 ± 4.92 years, BMI 23.73 ± 3.87), (symptomatic subjects = 27, mean age 27.6 ± 3.68 years, BMI 24.35 ± 3.86) were evaluated with a pressure algometer on the infraspinatus muscle belly, in four different positions of the upper quadrant: rest position (P1), passive scapular retraction position (P2), cervical contralateral inclination position (P3), and suprascapular nerve provocation position (P4). The assessed side was randomly chosen and all measurements were taken in sitting position.

RESULTS

No differences were observed between groups. The within-group analysis showed differences for both factors: "Positions" (F = 69.91; p = 0.001) and the interaction "Positions^Group" (F = 3.36; p = 0.02). The pairwise post-hoc analysis showed differences for the retracted position (P2) compared to others P1 (p = 0.001), P3 (p = 0.001), and P4 (p = 0.001), with higher PPT results achieved on the retracted position. Differences between P4 vs. P1 (p = 0.03) were also observed, with higher values for P4.

CONCLUSION

Placing the scapular girdle in a passive scapular retraction position significantly reduces the pressure sensitivity at the infraspinatus muscle. Physiotherapists can take into account these results when assessing and treating patients with upper quadrant pain syndromes.

Treatment of suprascapular nerve entrapment syndrome

Suprascapular nerve entrapment syndrome (SNES) is an often-overlooked etiology of shoulder pain and weakness. Treatment varies depending on the location and etiology of entrapment, which can be described as compressive or traction lesions. In some cases, treating the primary cause of impingement (ie. rotator cuff tear, ganglion cyst, etc.) is sufficient to relieve pressure on the nerve. In other cases where impingement is caused by dynamic microtrauma (as seen in overhead athletes and laborers), treatment is often more conservative. Conservative first-line therapy includes rehabilitation programs, nonsteroidal anti-inflammatory drugs, and lifestyle modification. Physical therapy is targeted at strengthening the rotator cuff muscles, trapezius, levator scapulae, rhomboids, serratus anterior, and deltoid muscle(s). If non-operative treatment fails to relieve suprascapular neuropathy, minimally invasive treatment options exist, such as suprascapular nerve injection, neurostimulation, cryoneurolysis, and pulsed radiofrequency. Multiple treatment modalities are often used synergistically due to variations in shoulder anatomy, physiology, pain response, and pathology as a sole therapeutic option does not seem successful for all cases. Often patients can be treated with non-invasive measures alone; however, injuries refractory to conservative treatment may require either arthroscopic or open surgery, particularly if the patient has an identifiable and reversible cause of nerve compression. Indications for invasive treatment include, but are not limited to, refractory to non-operative treatment, have a space-occupying lesion, or show severe signs and symptoms of muscle atrophy. Open decompression has fallen out of favor due to the advantages inherent in the less invasive arthroscopic approach.

Surgeon Strength: Ergonomics and Strength Training in Cardiothoracic Surgery

With the high prevalence of musculoskeletal pain in surgeons and interventionalists, it is critical to analyze the impact of ergonomics on cardiothoracic surgeon health. Here, we review the existing literature and propose recommendations to improve physical preparedness for surgery both in and outside the operating room. For decades, cardiothoracic surgeons have suffered from musculoskeletal pain, most commonly in the neck, and back due to a lack of proper ergonomics during surgery. A lack of dedicated ergonomics curriculum during training may leave surgeons at a high predisposition for work-related musculoskeletal disorders. We searched PubMed, Google Scholar, and other sources for studies relevant to surgical ergonomics and prevalence of musculoskeletal disease among surgeons and interventionalists. Whenever possible, data from quantitative studies, and meta-analyses are presented. We also contacted experts and propose an exercise routine to improve physical preparedness for demands of surgery. To date, many studies have reported astonishingly high rates of work-related pain in surgeons with rates as high as 87% in minimally-invasive surgeons. Several optimizations regarding correct table height, monitor positioning, and loupe angles have been discussed. Lastly, implementation of ergonomics training at some programs have been effective at reducing the rates of musculoskeletal pain among surgeons. Surgical work-related stress injuries are more common than we think. Many factors including smaller incisions and technological advancements have led to this plight. Ultimately, work-related injuries are underreported and understudied and the field of surgical ergonomics remains open for investigative study.

Decompression of the suprascapular nerve at the suprascapular notch under combined arthroscopic and ultrasound guidance

Decompression of the suprascapular nerve (SSNe) at the suprascapular notch (SSNo) is usually performed with an arthroscopic procedure. This technique is well described but locating the nerve is complex because it is deeply buried and surrounded by soft tissue. We propose to combine ultrasound and arthroscopy (US-arthroscopy) to facilitate nerve localization, exposure and release. The main objective of this study was to assess the feasibility of this technique. This is an experimental, cadaveric study, carried out on ten shoulders. The first step of our technique is to locate the SSNo using an ultrasound scanner. Then an arthroscope is introduced under ultrasound control to the SSNo. A second portal is then created to dissect the pedicle and perform the ligament release. Ultrasound identification of the SSNo, endoscopic dissection and decompression of the nerve were achieved in 100% of cases. Ultrasound identification of the SSNo took an average of 3 min (± 4) while dissection and endoscopic release time took an average of 8 min (± 5). Ultrasound is an extremely powerful tool for non-invasive localization of nerves through soft tissues, but it is limited by the fact that tissue visualization is limited to the ultrasound slice plane, which is two-dimensional. On the other hand, arthroscopy (extra-articular) allows three-dimensional control of the surgical steps performed, but the locating of the nerve involves significant tissue detachment and a risk of damaging the nerve with the dissection. The combination of the two (US-arthroscopy) offers the possibility of combining the advantages of both techniques.

Impact of 30 years' high-level rock climbing on the shoulder: an magnetic resonance imaging study of 31 climbers

BACKGROUND

Rock climbers are particularly susceptible to shoulder injuries due to repetitive upper-limb movements on vertical or overhanging terrain. However, the long-term effects of prolonged climbing on the shoulder joints are still unknown.

PURPOSE

The purpose of this study was to analyze the prevalence of pain and degenerative changes in the shoulder joints after high-level rock climbing over at least 25 years. We hypothesized that specific climber-associated patterns of degeneration would be found.

METHODS

Thirty-one adult male high-level rock climbers were compared to an age- and sex-matched control group of 31 nonclimbers. All participants underwent a detailed interview, standardized clinical examination, and bilateral (climbers) or unilateral (nonclimbers, dominant side) magnetic resonance imaging (MRI) scans. Clinical and MRI findings of the groups were compared.

RESULTS

The lifetime prevalence of shoulder pain in the rock climbers was 77%. The rock climbers had significantly more abnormalities in the labrum (82% vs. 52%; P = .002), long biceps tendon (53% vs. 23%; P = .006), and cartilage (28% vs. 3%; P = .005). These increased changes positively correlated with climbing intensity. There were no differences between the 2 groups with respect to rotator cuff tendon pathology (68% vs. 58%; P = .331) and acromioclavicular joint degeneration (88% vs. 90%; P = .713). Despite the increased degenerative changes in the rock climbers, their Constant score (CS) was still better than that of the nonclimbers (CS 94, interquartile range [IQR] 92-97, vs. CS 93, IQR 91-95; P = .019).

CONCLUSIONS

Prolonged high-level rock climbing leads to a high prevalence of shoulder pain and increased degenerative changes to the labrum, long biceps tendon, and cartilage. However, it is not related to any restriction in shoulder function.

Shoulder pain in a patient with renal cell carcinoma? Suprascapular neuropathy caused by bone metastasis of renal cell carcinoma: A case report

BACKGROUND

Pain management is crucial in palliative care for patients with advanced cancer. Here, we report a case of shoulder pain in a patient with renal cell carcinoma.

CASE PRESENTATION

A 36-year-old male diagnosed metastatic renal cell carcinoma presented with pain and weakness on left shoulder for more than 6 months. Physical examination showed limited range of motion and atrophic changes on supraspinatus and infraspinatus muscles. Weakness in shoulder abduction and external rotation was also noted.

POSSIBLE COURSES OF ACTION

In this case, suprascapular neuropathy, adhesive capsulitis of shoulder and metastatic lesions involving shoulder joint were suspected.

FORMULATION OF A PLAN

We planned imaging studies including X-ray, bone scan, magnetic resonance imaging, and electrodiagnostic studies.

OUTCOME

Imaging and electrodiagnostic studies showed suprascapular neuropathy by bone metastasis. Conservative treatment including injection and rehabilitation therapy reduced the patient's pain and improved the range of motion limitation.

LESSONS FROM THE CASE

Clinicians should be aware that bone metastasis in patients with advanced cancer can cause suprascapular neuropathy, shoulder pain and shoulder dysfunction.

VIEW ON RESEARCH PROBLEMS, OBJECTIVES, OR QUESTIONS GENERATED BY THE CASE

More research is expected on development of an early surveillance model, barriers to cancer pain management, communication from patients' perspectives.

The morphological stenosis pattern of the suprascapular notch is revealed yielding higher incidence in the discrete type and elucidating the inevitability of osteoplasty in horizontally oriented stenosis

PURPOSE

To identify the morphological patterns of suprascapular notch stenosis.

METHODS

Suprascapular notch space capacity was assessed by morphometric analysis of 333 dry scapulae. Suprascapular notch parameters-superior transverse distance, middle width, depth, medial border length and lateral border length-were measured. The probable suprascapular notch stenosis was referenced by (1) comparing each obtained parameter measurement to the range of the suprascapular nerve diameter, and (2) quantifying the reduced parameters. Finally, the morphological pattern was determined based on the collective reduction of the parameters and their alignments.

RESULTS

Five types of suprascapular notch based on depth to superior transverse distance ratio were identified and assessed. Type-I showed low incidence of stenosis (6/333) and low frequency within type (6/28) with potential risk of horizontal compression. Type-II showed relatively low incidence of stenosis (9/333) and low frequency within type (9/50) with undetermined pattern. Type-III showed relatively higher incidence of stenosis (47/333) but low frequency within type (47/158) with potential risk of vertical compression. Type-IV (foramen) showed low incidence of stenosis (6/333) and relatively lower frequency within type (6/26) with potential risk of encircled compression. Finally, type-V (discrete) showed relatively high incidence of stenosis (40/333) and high frequency within type (40/71) with potential risk of vertical compression. The suprascapular notch was found to be stenosed beyond its capacity to accommodate the suprascapular nerve in 49/333. Type-V is at most risk followed by Type-III.

CONCLUSIONS

Suprascapular notch stenosis takes three morphological patterns: horizontal, vertical or mixed. An osteoplasty of suprascapular notch margins may be required beside the common surgical approach of the superior transverse scapular ligamentectomy.

Comparison of clinical outcome of decompression of suprascapular nerve at spinoglenoid notch for patients with posterosuperior massive rotator cuff tears and suprascapular neuropathy

PURPOSE

In the present study, we aimed to determine whether decompression of suprascapular nerve (SSN) at the spinoglenoid notch could lead to a better functional outcome for the patients who underwent repairment of rotator cuff due to posterosupeior massive rotator cuff tear (MRCT) and suprascapular neuropathy.

METHODS

A total of 20 patients with posterosuperior MRCT and suprascapular neuropathy were analyzed in the present work. The preoperative magnetic resonance imaging (MRI) showed rotator cuff tear in supraspinatus and infraspinatus. All patients underwent arthroscopic rotator cuff repair. Patients were divided into two groups (group A: non-releasing, group B: releasing) according to whether the SSN at the spinoglenoid notch was decompressed. The modified University of California at Los Angeles shoulder rating scale (UCLA) and visual analog scale (VAS) questionnaire were adopted to assess the function of the affected shoulder preoperatively and 12 months after the operation. Electromyography (EMG) and nerve conduction study (NCS) were used to evaluate the nerve condition. Patients underwent MRI and EMG/NCS at 6 months after operation and last follow-up.

RESULTS

All patients were satisfied with the treatment. MRI showed that it was well-healed in 19 patients at 6 months after the operation. However, the fatty infiltration of supraspinatus and infraspinatus was not reversed. Only one patient in the non-releasing group showed the retear. The retear rate of group A and group B were 30% (3/10) and 20% (2/10) respectively at 12 months after the operation. One patient undergoing SSN decompression complained of discomfort in the infraspinatus area. His follow-up EMG after 6 months showed fibrillation potentials (1+) and positive sharp waves (1+) in the infraspinatus. The other patients' EMG results showed no abnormality. The postoperative UCLA and VAS scores were improved in both groups, and there was no significant difference in the follow-up outcomes between the two groups.

CONCLUSIONS

Patients with postersuperior MRCT and suprascapular neuropathy, decompression of suprascapular nerve at spinoglenoid notch didn't lead to a better functional outcome with the repairment of rotator cuff. Arthroscopic rotator cuff repair could reverse the suprascapular neuropathy.

LEVEL OF EVIDENCE

Level III.

Functional outcomes of internal fixation of scapula fractures due to high-velocity gunshot injuries

BACKGROUND

Open fractures of the scapula are relatively rare and only a few studies are interested in this subject. This study aims to demonstrate the results of internal fixation of open scapula fractures due to gunshot injuries.

MATERIALS AND METHODS

Eight patients who had open scapula fractures and were treated by internal fixation through the conventional Judet approach included in this study. Patients were followed up monthly in the first 6 months and every 2 months in the rest of the follow-up. Shoulder range of motion, Constant Shoulder Score, and Disabilities of the Arm, Shoulder, and Hand score were used for functional evaluation.

RESULTS

The average follow-up period was 34.6 ± 11.9 months. The average time between injuries and the surgery was 10.5 ± 5.1 days. The average shoulder abduction of the patients was 135.6 ± 18.8°, the average forward flexion of the shoulder was 160 ± 19.2°. The average internal and external rotations of the shoulders were 80 ± 14.1° and 63.1 ± 17.3°, respectively. CSS was calculated as 79.8 ± 14.4, and DASH was calculated as 14.1 ± 14.9.

CONCLUSIONS

In the treatment of open scapula fractures due to gunshot injuries, an internal fixation is a reliable option and the results were comparable with previous studies.

Did the prevalence of suprascapular neuropathy in professional volleyball players decrease with the changes occurred in serving technique?

Objectives: Suprascapular neuropathy is more frequent in volleyball as compared to other overhead sports. This study aims to report the actual prevalence of suprascapular neuropathy among elite volleyball players. The hypothesis is that becoming jump topspin serves the most common serving technique, suprascapular neuropathy reduced its frequency. Methods: A total of 82 professional players were enrolled in the study. The presence of symptoms and the type of serve preferably performed were investigated. The strength and trophicity of the supraspinatus and infraspinatus muscles were evaluated. Patients with positive clinical findings underwent MRI of the shoulder. Results: The jump topspin serve was found to be the most popular type of serve both in males and females. At physical examination, 9% of the males and 12% of the females presented with infraspinatus muscle hypotrophy. Each case was accompanied by external rotation weakness. None of them complained of pain or reduced performance when they played. MRI confirmed infraspinatus muscle atrophy in all subjects. Conclusion: A lower prevalence of suprascapular neuropathy was found as compared with that previously reported in the 1980s and 1990s. A reduction in the popularity of the float serve seems to be a possible explanation. Thus, the jump topspin serve could be safe for suprascapular neuropathy and associated injuries in volleyball. The findings of this study should be considered by athletes and coaches for the prevention of activity-related injuries.

Arthroscopic release of proximal supra-scapular nerve entrapment: Medium-term results

OBJECTIVE

To evaluate the clinical and electrophysiological results in the medium term of the arthroscopic release of the proximal entrapment of the suprascapular nerve.

MATERIAL AND METHOD

It is a retrospective study that includes 75 patients with idiopathic entrapment of the suprascapular nerve in the suprascapular notch in whom conservative treatment has failed. All patients underwent electrophysiological tests (EMG) as well as clinical test (Constant and DASH test) preoperatively and during follow-up.

RESULTS

75 patients (53 women and 22 men) with a mean age of 44.1 ± 10.7 years met study criteria with a mean follow-up of 63.7 ± 29.1 months. Preoperatively the DASH value was 78,6 ± 10,2, the Constant test value was 37.1 ±8.8 and the EVA value was 8.8 ± 1.1 while the values in the last revision were 19.4 ± 15.8 for DASH, 80.2 ± 9.6 (for the CS and 2 ±1.3 for the EVA scale; the differences were significant in all cases (P<.001). Regarding the results of the electrophysiological test, preoperatively there were 21 very severe grades (28%), 32 severe (42.6%), 17 moderate (22.6%) and 5 mild (6.6%). While in the last review there were 3 severe degrees (4%), 6 moderate (8%), 40 mild (53.3%) and 26 normal (34.6%). There was no very severe grade (0%); 3 patients (4%) had to be reoperated due to persistent symptons.

CONCLUSIONS

The arthroscopic release of idiopathic entrapment of the suprascapular nerve in the superior scapular notch achieved good clinical and electrophysiological results in the medium term.

LEVEL OF EVIDENCE

iv; case series; treatment study.

"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.

Clinico-radiological review of peripheral entrapment neuropathies - Part 1 upper limb

PURPOSE

This article aims to review the pertinent anatomy, etiopathogenesis, current clinical and radiological concepts and principles of management in case of upper limb entrapment neuropathies.

METHODS

The review is based on critical analysis of the existing literature as well as our experience in dealing with entrapment neuropathies.

RESULTS

Entrapment neuropathies of the upper limb peripheral nerves are common conditions that are often misdiagnosed because of their varying clinical presentations and lack of standardized diagnostic methods. Clinical assessment and electrodiagnostic studies have been the mainstay; however, imaging techniques have provided newer insights into the pathophysiology of these entities, leading to a paradigm shift in their diagnosis and management. The current best practice protocols for entrapment syndromes are constantly evolving with increasing emphasis on the role high-resolution ultrasound and magnetic resonance imaging. Many imaging criteria are described and we have tried to present the most validated measurements for diagnosing entrapment neuropathies.

CONCLUSION

It is imperative for a clinical radiologist to be familiar with the etiopathogenesis and clinical features of these conditions, in addition to being thorough with the anatomy and the latest imaging strategies.

The Evaluation and Management of Suprascapular Neuropathy

Suprascapular neuropathy is a potential source of shoulder pain and functional limitation that can present secondary to various etiologies including entrapment or compression. Cystic lesions arising from a labral or capsular tear can compress the nerve along its course over the scapula. Nerve traction is theorized to arise from chronic overhead athletics or due to a retracted rotator cuff tear. The diagnosis of suprascapular neuropathy is based on a combination of a detailed history, a comprehensive physical examination, imaging, and electrodiagnostic studies. Although the anatomic course and variations in bony constraint are well understood, the role of surgical treatment in cases of suprascapular neuropathy is less clear. Recent reviews on the topic have shed light on the outcomes after the treatment of suprascapular neuropathy because of compression, showing that surgical release can improve return to play in well-indicated patients. The incidence of compressive neuropathy is quite high in the overhead athletic cohort, but most patients do not show clinically relevant deficiencies in function. Surgical release is therefore not routinely recommended unless patients with pain or deficits in strength fail appropriate nonsurgical treatment.

Suprascapular Neuropathy around the Shoulder: A Current Concept Review

Suprascapular neuropathy is an uncommon but increasingly recognized cause of shoulder pain and dysfunction due to nerve entrapment. The aim of this review is to summarize some important aspects of this shoulder pathology. An extensive research was performed on PubMed and Clinical Key. The goal was to collect all the anatomical, biomechanical and clinical studies to conduct an extensive overview of the issue. Attention was focused on researching the state of art of the diagnosis and treatment. A total of 59 studies were found suitable and included. This condition is more frequently diagnosed in over-head athletes or patients with massive rotator cuff tears. Diagnosis may be complex, whereas its treatment is safe, and it has a great success rate. Prompt diagnosis is crucial as chronic conditions have worse outcomes compared to acute lesions. Proper instrumental evaluation and imaging are essential. Dynamic compression must initially be treated non-operatively. If there is no improvement, surgical release should be considered. On the other hand, soft tissue lesions may first be treated non-operatively. However, surgical treatment by arthroscopic means is advisable when possible as it represents the gold standard therapy. Other concomitant shoulder lesions must be recognized and treated accordingly.

MRI diagnosis of suprascapular neuropathy using spinoglenoid notch distension

PURPOSE

To assess the use of a spinoglenoid notch distension measurement as a radiographic marker on MRI to aid the diagnosis of suprascapular neuropathy.

METHODS

Spinoglenoid notch distension was compared on MRI by blinded independent observers for two patient cohorts: one group with an electromyography/nerve conduction study confirmed diagnosis of suprascapular neuropathy who underwent arthroscopic suprascapular nerve decompression, and a control group of patients aged 18-30 years with a normal shoulder MRI.

RESULTS

Sixty suprascapular nerve patients (average age 52 years) were compared to 47 control patients (average age 24 years). Intra-rater and inter-rater reliability showed excellent agreement between reviewers for all measurements. There was a significant difference in the mean spinoglenoid notch distension for the SSN group (m = 8.36, SD = 2.42) compared to the control group (m = 5.7, SD = 1.56); [t(212) = 9.40, p < 0.0001].

CONCLUSION

The spinoglenoid notch distension is significantly increased in patients with suprascapular neuropathy. We hypothesize that hypertrophy of the transverse scapular ligament creates a venous obstruction resulting in varicosities of the suprascapular vein which runs with the nerve under the ligament. This distends the spinoglenoid notch and can be enlarged in cases of suprascapular neuropathy which is evident on MRI.

Ultrasound-guided interventions for painful shoulder: from anatomy to evidence

Shoulder pain is a common musculoskeletal disorder of variable etiology, ranging from rotator cuff pathology to peripheral nerve entrapment. Advances in ultrasound (US) technology have allowed static and dynamic evaluation of shoulder problems and most importantly, offer real-time, radiation-free guidance for interventions. The present review aims to describe shoulder anatomy in detail using information from cadaveric models and to illustrate US-guided techniques using clearly labeled figures and videos. The review will also present evidence of specific US-guided therapies for shoulder pain by summarizing landmark studies, systematic reviews, and meta-analyses. The following shoulder structures will be covered: 1) the biceps long head tendon, 2) the acromioclavicular joint, 3) the subacromial-subdeltoid bursa, 4) the glenohumeral joint, 5) the suprascapular nerve, and 6) the axillary nerve.

Shoulder Arthroscopy With Versus Without Suprascapular Nerve Release: Clinical Outcomes and Return to Sport Rate in Elite Overhead Athletes

PURPOSE

To compare the clinical outcomes and return to sport rate between elite overhead athletes who underwent shoulder arthroscopy and decompression of the suprascapular nerve (SSN) versus overhead athletes who underwent shoulder arthroscopy without SSN release.

METHODS

From 2007 to 2014, high-level overhead athletes diagnosed with a rotator cuff tear and/or a glenoid labral lesion and SSN entrapment were included in the study if their symptoms did not improve with nonoperative treatment and if they agreed to undergo surgery and participate. Their preoperative University of California at Los Angeles (UCLA) shoulder score, bilateral postoperative Constant scores, postoperative UCLA score, and return to sport rate were evaluated and compared with those of a group of elite athletes who had a similar diagnosis but refused to undergo SSN decompression during shoulder arthroscopy.

RESULTS

Thirty-five athletes (25 male, 10 female) were included in the SSN decompression group (group 1), and 21 athletes were included in the non-SSN decompression group (group 2). The mean age was 27 years (range: 19-34) and 24 years (range: 21-32) in group 1 and group 2, respectively (P = .56). The mean follow-up time was 38.4 months (24-50 months) in group 1 and 42.2 months (26-53 months) in group 2 (P = .09). Both groups had significantly improved UCLA scores after surgery (P < .05). The postoperative UCLA (P = .01) and Constant scores (P < .001) were significantly higher in the SSN decompression group. The mean difference in Constant score between the affected and the unaffected side was 4 points (range: 2-12) in the SSN decompression group and 8 points (range: 4-14) in the non-SSN decompression group postoperatively (P = .0002). In both groups, 100% of patients reached the patient acceptable symptom state value for Constant score at follow-up. For the UCLA score, patients who underwent SSN decompression had significantly higher pre- to postoperative improvement than the nondecompression group (P = .016). The return to sport rate was 97% in group 1 and 84% in group 2. The mean length of career was 2.1 years (range: 1.5-2.4 years) and 2.3 years (range: 1.2-3.2 years) in group 1 and group 2, respectively.

CONCLUSIONS

In elite overhead athletes with shoulder pathology and SSN entrapment, combined shoulder arthroscopy and SSN release yield superior clinical outcomes, greater improvement in UCLA score, and a higher return to sport rate than shoulder arthroscopy without SSN decompression. Regardless of SSN treatment, both groups achieved the patient acceptable symptom state after shoulder arthroscopy.

LEVEL OF EVIDENCE

Level III, comparative case series.

Intraneural cyst of the supraescapular nerve: Atypical cause of peripheral nerve entrapment syndrome. Case report and literature review

OBJECTIVE

Intraneural cysts are benign lesions located within the epineurium of some peripheral nerves and their aetiopathogenesis is controversial. Most are located at the level of the lower limbs. In the upper limbs, the most frequently affected nerve is the ulnar nerve. Suprascapular nerve entrapment syndrome due to the formation of an intraneural cyst is rare. In this article, we show a new case and perform a literature review of intraneural cysts located in the suprascapular nerve.

METHODS

We present a 49-year-old woman with pain in the lateral shoulder region of several months' evolution. A brachial plexus MR showed a tumour of approximately 2×1.5cm, with a cystic appearance, in relation to the upper trunk of the right brachial plexus.

RESULTS

We used a supra-infraclavicular approach. The cystic tumour affected the suprascapular nerve. After locating a zone on the surface without nervous fascicles, we performed a partial resection of the capsule and emptying of the cyst, with a xanthochromic gelatinous content. The anatomopathological examination confirmed the diagnosis of intraneural cyst.

CONCLUSION

The suprascapular nerve is a mixed nerve, coming from the upper trunk. It provides the motor branches to the supraspinatus and infraspinatus muscle. Compression of the suprascapular nerve leads to atrophy of these muscles. This entity is one of the differential diagnoses in a patient with pain irradiating to the shoulder, and its correct treatment often results in complete remission of symptoms.