Suprascapular neuropathy: diagnosis and management

Parsonage-Turner syndrome, affecting suprascapular nerve and especially to infraspinatus muscles after COVID-19 vaccination in a professional wrestler, a case report and literature review of causes and treatments

BACKGROUND

Acute peripheral neuropathy, also known as Parsonage-Turner syndrome or neuralgic amyotrophy, mostly affects the upper brachial plexus trunks, which include the shoulder girdle. It is typically accompanied by abrupt, intense pain, weakness, and sensory disruption. The etiology and causes of this disease are still unknown because of its low prevalence, however viral reactions-induced inflammation is one of its frequent causes.

CASE PRESENTATION

Here, we introduce a professional wrestler patient who was diagnosed with PTS after vaccination and was treated, and we review some articles in this field.

CONCLUSION

When it comes to shoulder-girdle complaints and pain, Parsonage-Turner syndrome can be a differential diagnosis. Corticosteroids during the acute period, followed by physical therapy, appear to be an efficient way to manage pain, inflammation, muscular atrophy, and the process of recovering to full nerve regeneration.

A rare presentation of a large suprascapular fossa lipoma causing suprascapular nerve traction injury leading to massive rotator cuff tear, treated arthroscopically - case report

Suprascapular fossa lipoma extending to the suprascapular notch causing traction injury to the suprascapular nerve is a rare presentation. We report a 47-year-old male with progressive weakness of the right shoulder joint of 8 months duration, with a palpable mass over the spine of the scapula was noticed 2 months earlier and developed a sudden drop in arm following a moderate strain. A magnetic resonance imaging (MRI) scan revealed a rotator cuff tear involving the supraspinatus and infraspinatus muscles with a tumor like lesion in the suprascapular fossa, displacing the suprascapular muscle mass and extending into the suprascapular notch. Electromyography and nerve conduction velocity studies revealed suprascapular neuropathy. After histopathologic confirmation, an arthroscopic excision of the mass with decompression of the suprascapular notch was performed along with repair of the rotator cuff. Six months after the procedure, the patient had improved considerably in terms of function and postoperative MRI revealed a complete excision of the mass, and further follow-up of 2 years showed no recurrence. Suprascapular nerve entrapment can be caused by a lipoma in the shoulder, leading to weakness, atrophy, and consequent tear of the rotator cuff tendons. Arthroscopic management, after histopathological confirmation, gives good results in this situation. LEVEL OF EVIDENCE: Level IV.

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.

Pectoralis minor syndrome - review of pathoanatomy, diagnosis, and management of the primary cause of neurogenic thoracic outlet syndrome

Thoracic outlet syndrome is an umbrella term for compressive pathologies in the supraclavicular and infraclavicular fossae, with the vast majority being neurogenic in nature. These compressive neuropathies, such as pectoralis minor syndrome, can be challenging problems for both patients and physicians. Robust understanding of thoracic outlet anatomy and scapulothoracic biomechanics are necessary to distinguish neurogenic vs. vascular disorders and properly diagnose affected patients. Repetitive overhead activity, particularly when combined with scapular dyskinesia, leads to pectoralis minor shortening, decreased volume of the retropectoralis minor space, and subsequent brachial plexus compression causing neurogenic thoracic outlet syndrome. Combining a thorough history, physical examination, and diagnostic modalities including ultrasound-guided injections are necessary to arrive at the correct diagnosis. Rigorous attention must be paid to rule out alternate etiologies such as peripheral neuropathies, vascular disorders, cervical radiculopathy, and space-occupying lesions. Initial nonoperative treatment with pectoralis minor stretching, as well as periscapular and postural retraining, is successful in the majority of patients. For patients that fail nonoperative management, surgical release of the pectoralis minor may be performed through a variety of approaches. Both open and arthroscopic pectoralis minor release may be performed safely with effective resolution of neurogenic symptoms. When further indicated by the preoperative workup, this can be combined with suprascapular nerve release and brachial plexus neurolysis for complete infraclavicular thoracic outlet decompression.

A Review of Upper Extremity Peripheral Nerve Injuries in Throwing Athletes

Peripheral nerve injuries in the upper extremities may be common in throwing athletes as the throwing motion places extreme stress on the dominant arm. The combination of extreme stress along with repetitive microtrauma from throwing uniquely places the throwing athlete at elevated risk of upper extremity peripheral nerve injury. However, because symptoms can be non-specific and frequent co-exist with pathology in the upper extremity, the diagnosis of peripheral nerve injury is often delayed. Diagnosis of peripheral nerve injuries may require a combination of history and physical exam, diagnostic imaging, electrodiagnostic testing, and diagnostic ultrasound guided injections. The primary management should include physical therapy focusing on throwing mechanics and kinetic chain evaluation. However, some athletes require surgical intervention if symptoms do not improve with conservative management. The purpose of this focused narrative review is to highlight upper extremity peripheral neuropathies reported in throwing athletes and to provide an overview of the appropriate clinical diagnosis and management of the throwing athlete with a peripheral nerve injury. This article is protected by copyright. All rights reserved.

Superior Capsular Reconstruction: A Systematic Review of Surgical Techniques and Clinical Outcomes

PURPOSE

To evaluate surgical techniques and clinical outcomes of arthroscopic superior capsular reconstruction (SCR) for the treatment of massive irreparable rotator cuff tears.

METHODS

A systematic review was registered with PROSPERO and performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The PubMed, Scopus, and Cochrane databases were searched. Studies investigating SCR with reported surgical techniques were included. Animal studies, cadaveric studies, review studies, and letters to the editor were excluded. The technical aspects of the surgical techniques for SCR were analyzed in each article, which included graft type, glenoid fixation method, greater tuberosity fixation method, graft passage technique, suture management, margin convergence, concomitant procedures, and postoperative rehabilitation protocol. Clinical outcomes, when available, were also analyzed.

RESULTS

We screened 365 articles, of which 29 described surgical techniques for SCR. According to the Modified Coleman Methodology Score, 24 articles were rated as poor (score < 55), 4 were rated as fair (score between 55 and 69), and 1 was rated as good (score between 70 and 84), with an average score of 25.8 ± 20.9. The most commonly performed technique for SCR used the following: an acellular dermal allograft, 2 biocomposite suture anchors for glenoid fixation, transosseous-equivalent double-row suture anchor fixation for greater tuberosity fixation with 2 biocomposite medial-row anchors and 2 biocomposite lateral-row anchors, the double-pulley technique combined with an arthroscopic grasper and/or pull suture to pass the graft into the shoulder, the performance of both anterior and posterior margin convergence, and a native rotator cuff repair when possible. Only 8 studies reported clinical outcomes, and they showed that SCR provides significant improvement in patient-reported outcomes, significant improvement in shoulder range of motion, variable graft failure rates, low complication rates, and variable reoperation rates. There were no studies comparing outcomes among the various surgical techniques.

CONCLUSIONS

Many surgical techniques exist for arthroscopic SCR. However, no superior technique was shown because there were no studies comparing clinical outcomes among these various techniques.

LEVEL OF EVIDENCE

Level V, systematic review of Level III, IV, and V studies.

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.

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.

Editorial Commentary: Suprascapular Neuropathy in Overhead Athletes: To Release or Not to Release?

A growing body of evidence has demonstrated that repetitive overhead athletes with shoulder pathology often have associated infraspinatus atrophy and suprascapular neuropathy. Although decompression of the suprascapular nerve has not been shown to clearly impact outcomes in the general population, release of the nerve in overhead athletes with documented evidence of impingement may improve outcomes in this high-demand population.

Anatomic landmarks for arthroscopic suprascapular nerve decompression

PURPOSE

Arthroscopic suprascapular nerve (SSN) decompression has become a more frequently utilized procedure in the treatment of SSN entrapment and has gained popularity over recent years. Despite increasing technical notes and outcomes information regarding this technique, there remains a paucity of data with respect to clear anatomic guidelines for teaching this procedure. The purpose of this study was to provide guidelines that are visible arthroscopically and palpable externally to allow safer and more efficient surgery for arthroscopic decompression by analysing the superior scapular anatomy with respect to local landmarks.

METHODS

A cadaveric study was used to examine neurovascular structural measurements obtained in twelve cadavera with 23 usable shoulders. Arthroscopic dissection of the pertinent anatomy as determined by previously described approaches was followed by meticulous open regional dissection and measurements of the local landmarks.

RESULTS

Measurements of the pertinent arthroscopic anatomy with respect to local landmarks of the superior shoulder were recorded in 23 shoulders and are included herein. Measurements taken arthroscopically on 22 shoulders revealed that the lateral insertion of the transverse suprascapular ligament to the acromioclavicular joint was 3.6 cm (SD 0.5 cm). One of the anatomic measurements on open dissection had a significant correlation with our subject's demographics and was found between cadaveric height and the linear distance from the lateral acromion to the suprascapular notch (mean distance = 66.53 ± 5.30 mm; Pearson's correlation = 0.739; p = 0.006).

CONCLUSIONS

This cadaveric study describes meaningful landmarks and their measurements, which are identifiable arthroscopically and enable safer surgery in this area. Using these numbers, surgeons can know that it is safe to bluntly dissect to 2.5 cm medial to the acromioclavicular joint (and 5 cm medial to the palpable lateral acromion) before dissection is likely to encounter the SSN or artery. This knowledge will allow surgeons to learn this surgical technique, and for surgical educators to safely teach dissection and release in this uncommonly accessed anatomic region.

Occupational mononeuropathies in industry

Peripheral nerve injuries have the potential to cause significant disability and can be commonly associated with recreational and occupational activities. Acute nerve injuries are mainly related to violent trauma, while repeated mechanical trauma due to external forces or repetitive motions can produce chronic nerve compression injury. This chapter will present a narrative review of the existing evidence of the association between peripheral compressive nerve disorders and work-related risk factors. Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy in the general population and in working populations employed in manual repetitive and forceful activities. The work-relatedness of CTS is essentially based on epidemiologic evidence and the results of experimental studies showing the capability of repetitive wrist extreme postures, associated with hand-wrist forceful exertions, to increase the pressure inside the carpal tunnel and to compress the median nerve. Assembly industry, food processing and packaging, hand-arm vibrating tools, and jobs involving high-repetition, high-force tasks put workers at risk for CTS. Less strong evidence exists of the association between ulnar elbow neuropathy and manual tasks or repetitive stretch on squatting and peroneal nerve neuropathy at the fibular head. Very few reports are available about the association between occupation and other compressive peripheral nerve injuries.

Carpal and cubital tunnel and other, rarer nerve compression syndromes

BACKGROUND

Carpal tunnel syndrome is by far the most common peripheral nerve compression syndrome, affecting approximately one in every six adults to a greater or lesser extent. Splitting the flexor retinaculum to treat carpal tunnel syndrome is the second most common specialized surgical procedure in Germany. Cubital tunnel syndrome is rarer by a factor of 13, and the other compression syndromes are rarer still.

METHODS

This review is based on publications retrieved by a selective literature search of PubMed and the Cochrane Library, along with current guidelines and the authors' clinical and scientific experience.

RESULTS

Randomized controlled trials have shown, with a high level of evidence, that the surgical treatment of carpal tunnel syndrome yields very good results regardless of the particular technique used, as long as the diagnosis and the indication for surgery are well established by the electrophysiologic and radiological findings and the operation is properly performed. The success rates of open surgery, and the single-portal and dual-portal endoscopic methods are 91.6%, 93.4% and 92.5%, respectively. When performed by experienced hands, all these procedures have complication rates below 1%. The surgical treatment of cubital tunnel syndrome has a comparably low complication rate, but worse results overall. Neuro-ultrasonography and magnetic resonance imaging (neuro-MRI) are increasingly being used to complement the diagnostic findings of electrophysiologic studies.

CONCLUSION

Evidence-based diagnostic methods and treatment recommendations are now available for the two most common peripheral nerve compression syndromes. Further controlled trials are needed for most of the rarer syndromes, especially the controversial ones.

Complete Fatty infiltration of intact rotator cuffs caused by suprascapular neuropathy

Suprascapular neuropathy is generally considered to be a diagnosis of exclusion, although it has been described in association with several activities and conditions. To our knowledge, this is the first description of suprascapular neuropathy with complete neurogenic fatty replacement in patients with intact rotator cuff tendons in the absence of traction or compression mechanisms. We present 4 cases of patients who presented with complete fatty infiltration of the supraspinatus (1 patient), infraspinatus (2 patients), and both (1 patient) resulting from suprascapular neuropathy. Each of these patients underwent arthroscopic suprascapular nerve decompression and subsequently had immediate improvement in pain and subjective shoulder value.

Inflammation: therapeutic targets for diabetic neuropathy

There are still no approved treatments for the prevention or of cure of diabetic neuropathy, and only symptomatic pain therapies of variable efficacy are available. Inflammation is a cardinal pathogenic mechanism of diabetic neuropathy. The relationships between inflammation and the development of diabetic neuropathy involve complex molecular networks and processes. Herein, we review the key inflammatory molecules (inflammatory cytokines, adhesion molecules, chemokines) and pathways (nuclear factor kappa B, JUN N-terminal kinase) implicated in the development and progression of diabetic neuropathy. Advances in the understanding of the roles of these key inflammatory molecules and pathways in diabetic neuropathy will facilitate the discovery of the potential of anti-inflammatory approaches for the inhibition of the development of neuropathy. Specifically, many anti-inflammatory drugs significantly inhibit the development of different aspects of diabetic neuropathy in animal models and clinical trials.