Suprascapular neuropathy. Results of non-operative treatment

Spontaneous resolution of spinoglenoid ganglion cyst: a case series

BACKGROUND

Spontaneous resolution of a spinoglenoid notch ganglion cyst (SGC) without surgical treatment has been rarely reported; however, we have encountered this phenomenon occasionally. Therefore, we aimed to describe a case series of consecutive patients with SGC in whom it spontaneously resolved without surgical treatment.

METHODS

We retrospectively reviewed 12 patients with magnetic resonance imaging (MRI)-confirmed SGC in whom it resolved without surgical treatment between January 2011 and March 2023. We included patients without abnormally increased signal intensity or muscle atrophy due to denervation from suprascapular neuropathy on MRI. Resolution of the SGC was confirmed via MRI or ultrasound at the follow-up visit, and suprascapular neuropathy was assessed using electromyography and nerve conduction studies when needed. For functional assessments, the visual analog scale for pain and active range of motion of the shoulder were used to compare pre and postresolution follow-ups.

RESULTS

Eleven men and 1 woman with a median age of 54.0 years (interquartile range [IQR] 37.0-65.3) were included in this study. The SGCs resolved spontaneously at a median of 13.2 months with an IQR of 8.2-23.0 after initial evaluation using MRI. The SGCs were multiloculated cysts with superior labrum anterior and posterior II-IX lesions, with a median diameter of 2.5 cm (IQR 2.0-2.8). The median visual analog scale for pain (pre-resolution 5.0 [IQR 4.0-7.0] vs postresolution 1.0 [IQR 0.0-1.0], P = .002) and internal rotation at the back (preresolution 8.0 [IQR 7.0-10.3] vs postresolution 7.5 [IQR 7.0-8.0], P = .034) were significantly improved after the resolution.

CONCLUSIONS

Surgical treatment may not be necessary in all cases of SGC. Nonsurgical treatment may be a viable option in the absence of suprascapular nerve involvement or superior labrum anterior and posterior-related physical findings.

Spinoglenoid Notch Ganglion Cyst: A Case Report

Suprascapular nerve dysfunction caused by ganglion cysts is a rare condition that can cause significant pain and weakness in the shoulder. The suprascapular nerve is a branch of the brachial plexus that innervates the supraspinatus and infraspinatus muscles. It is most commonly compressed at the suprascapular notch or the spinoglenoid notch. A 40-year-old male presented with a two-year history of left shoulder pain that was aggravated by overhead activities. Physical examination revealed mild tenderness along the infraspinatus with noticeable atrophy, full range of motion, and mild external rotation weakness. MRI was obtained and confirmed the suspected diagnosis of suprascapular nerve dysfunction caused by a ganglion cyst at the spinoglenoid notch. The patient was initially treated conservatively with physical therapy and non-steroidal anti-inflammatory drugs (NSAIDs), but after completing nine months of conservative management, he showed no improvement. The patient elected to undergo open ganglion cyst excision and decompression of the spinoglenoid notch. Postoperatively, the patient's pain resolved gradually and he regained the full power of external rotation. The patient was followed for one year postoperatively and was satisfied with the outcome with a full range of motion, full power, and a complete return to his baseline level of activity. In conclusion, this case report demonstrates the successful treatment of suprascapular nerve dysfunction caused by a ganglion cyst at the spinoglenoid notch with open ganglion cyst excision and decompression. This procedure is a safe and effective treatment option for patients with this condition who have failed to respond to conservative treatment and emphasizes and signifies the role of eliciting a detailed patient history, conducting a thorough radiographic examination including MRI scans, and planning optimum surgical interventions.

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.

Entrapment Neuropathies of the Shoulder

Entrapment neuropathies of the shoulder most commonly involve the suprascapular or axillary nerves, and they primarily affect the younger, athletic patient population. The extremes of shoulder mobility required for competitive overhead athletes, particularly in the position of abduction and external rotation, place this cohort at particular risk. Anatomically, the suprascapular nerve is most prone to entrapment at the level of the suprascapular or spinoglenoid notch; the axillary nerve is most prone to entrapment as it traverses the confines of the quadrilateral space.Radiographs should be ordered as a primary imaging study to evaluate for obvious pathology occurring along the course of the nerves or for pathology predisposing the patient to nerve injury. Magnetic resonance imaging plays a role in not only identifying any mass-compressing lesion along the course of the nerve, but also in identifying muscle signal changes typical for denervation and/or fatty atrophy in the distribution of the involved nerve.

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.

Clinical Outcomes of Arthroscopic Suprascapular Nerve Decompression for Suprascapular Neuropathy

PURPOSE

To report clinical outcomes following arthroscopic suprascapular nerve (SSN) decompression for suprascapular neuropathy at the suprascapular and/or spinoglenoid notch in the absence of major concomitant pathology.

METHODS

We retrospectively reviewed prospectively collected data of 19 patients who underwent SSN release at the suprascapular and/or spinoglenoid notch between April 2006 and August 2017 with ≥2 years of follow-up. Patients who underwent concomitant rotator cuff or labral repairs or had severe osteoarthritis were excluded. Pre- and postoperative strength and patient-reported outcomes were collected, including the American Shoulder and Elbow Surgeons (ASES), Single Assessment Numerical Evaluation (SANE), Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH), 12-item Short Form (SF-12), and satisfaction. Complications and revisions were recorded.

RESULTS

At a mean final follow-up of 4.8 years, pre- to postoperative ASES (64.9 ± 18.7 versus 83.5 ± 23.1; P = .018), QuickDASH (28.7 ± 17.2 versus 12.7 ± 17.1; P = .028), SANE (64.3 ± 16.4 versus 80.8 ± 22.3; P = .034), and SF-12 PCS (41.1 ± 10.8 versus 52.3 ± 5.8; P = .007) scores all significantly improved. Median strength for external rotation improved significantly (4 [range 2 to 5] versus 5 [range 3 to 5]; P = .014). There was no statistically significant improvement in median strength for abduction (4 [range 3 to 5] versus 5 [5]; P = .059). Median postoperative satisfaction was 9 (range 1 to 10), with 8 patients (50%) rating satisfaction ≥9. No complications were observed, and no patients went on to revision surgery.

CONCLUSION

Arthroscopic SSN decompression for suprascapular neuropathy at the suprascapular and/or spinoglenoid notch in the absence of major concomitant glenohumeral pathology results in good functional outcomes with significant improvements from before to after surgery.

LEVEL OF EVIDENCE

IV, therapeutic case series.

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.

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.

"Isolated" Suprascapular Neuropathy: Compression, Traction, or Inflammation?

BACKGROUND

Several hypotheses have been proposed for the pathophysiology of suprascapular nerve (SSN) palsy, including compression, traction, and nerve inflammation.

OBJECTIVE

To provide insight into the pathophysiology of isolated nontraumatic SSN palsy by performing critical reinterpretations of electrodiagnostic (EDX) studies and magnetic resonance (MR) images of patients with such diagnosis.

METHODS

We retrospectively reviewed all patients referred to our institution for the past 20 yr with a diagnosis of nontraumatic isolated suprascapular neuropathy who had an upper extremity EDX study and a shoulder or brachial plexus MR scan. Patient charts were reviewed to analyze their initial clinical examination, and their original EDX study and MR images were reinterpreted by an experienced neurologist and a musculoskeletal radiologist, respectively, both blinded from the authors' hypothesis and from each other's findings.

RESULTS

Fifty-nine patients were included. Fifty of them (85%) presented with at least 1 finding that was inconsistent with an isolated SSN palsy. Forty patients (68%) had signs on physical examination beyond the SSN distribution. Thirty-one patients (53%) had abnormalities on their EDX studies not related to the SSN. Twenty-two patients (37%) had denervation atrophy in other muscles than the spinati, or neural hyperintensity in other nerves than the SSN on their MR scans, without any evidence of SSN extrinsic compression.

CONCLUSION

The great majority of patients with presumed isolated SSN palsy had clinical, electrophysiological, and/or imaging evidence of a more diffuse pattern of neuromuscular involvement. These data strongly support an inflammatory pathophysiology in many cases of "isolated" SSN palsy.

Hourglass-like constriction of the suprascapular nerve: a contraindication for minimally invasive surgery

BACKGROUND

Suprascapular nerve (SSN) entrapment is usually ascribed to static or dynamic compression. When no cause of compression is found, SSN entrapment is defined as idiopathic. Focal hourglass-like constriction (H-LC) of the SSN that results in muscle paralysis represents an unusual condition that may be misinterpreted and erroneously diagnosed as SSN entrapment or as neuralgic amyotrophy.

METHODS

With the aim of finding clinical and surgical clues that could differentiate the traditional form of idiopathic SSN entrapment from the rare H-LC, a series of 6 cases of SSN palsy caused by H-LC is presented.

RESULTS

All but 1 supraspinatus muscle recovered M5 muscle strength. The Constant shoulder score was excellent in 3 patients, good in 1, fair in 1, and poor in 1.

DISCUSSION

If a diagnosis is not made in time, H-LC may evolve from mild to severe nerve torsion that may require a shift in surgical procedure from epineurotomy and external neurolysis to focal resection and suture. If an incorrect therapy is chosen, the chance of recovery might be definitively compromised with the persistence of muscle palsy. Conversely, when SSN palsy persists despite notch decompression, especially when it is performed with a limited open approach or arthroscopically, concerns about the real etiology and location of nerve compression responsible for the nerve palsy may arise.

CONCLUSION

When approaching SSN pathology, H-LC should be considered as a potential cause of nerve palsy, as it may represent a contraindication for a limited open approach or arthroscopic decompression.

Arthroscopic management of suprascapular neuropathy of the shoulder improves pain and functional outcomes with minimal complication rates

PURPOSE

The purpose of this study was to systematically assess the arthroscopic management of suprascapular neuropathy, including the aetiology, surgical decision-making, clinical outcomes, and complications associated with the procedure.

METHODS

Three databases [PubMed, Ovid (Medline), and Embase] were searched. Systematic literature screening and data abstraction was performed in duplicate to present a review of studies reporting on arthroscopic management of suprascapular neuropathy. The quality of the included studies was assessed using level of evidence and the MINORS (Methodological Index for Nonrandomized Studies) checklist.

RESULTS

In total, 40 studies (17 case reports, 20 case series, 2 retrospective comparative studies, and 1 prospective comparative study) were identified, including 259 patients (261 shoulders) treated arthroscopically for suprascapular neuropathy. The most common aetiology of suprascapular neuropathy was suprascapular nerve compression by a cyst at the spinoglenoid notch (42%), and the decision to pursue arthroscopic surgery was most commonly based on the results of clinical findings and investigations (47%). Overall, 97% of patients reported significant improvement in or complete resolution of their pre-operative symptoms (including pain, strength, and subjective function of the shoulder) over a mean follow-up period of 23.7 months. Further, there was a low overall complication rate (4%) associated with the arthroscopic procedures.

CONCLUSION

While most studies evaluating arthroscopic management of suprascapular neuropathy are uncontrolled studies with lower levels of evidence, results indicate that such management provides patients with significant improvements in pain, strength, and subjective function of the shoulder, and has a low incidence of complications. Patients managed arthroscopically for suprascapular neuropathy may expect significant improvements in pain, strength, and subjective function of the shoulder.

LEVEL OF EVIDENCE

Level IV, systematic review of level II to IV studies.

Suprascapular Nerve Pathology: A Review of the Literature

Background:

Suprascapular nerve pathology is a rare diagnosis that is increasingly gaining popularity among the conditions that cause shoulder pain and dysfunction. The suprascapular nerve passes through several osseoligamentous structures and can be compressed in several locations.

Methods:

A thorough literature search was performed using online available databases in order to carefully define the pathophysiology and to guide diagnosis and treatment.

Results:

Suprascapular neuropathy diagnosis is based on a careful history and a thorough clinical and radiological examination. Although the incidence and prevalence of the condition remain unknown, it is highly diagnosed in specific groups (overhead athletes, patients with a massive rotator cuff tear) probably due to higher interest. The location and the etiology of the compression are those that define the treatment modality.

Conclusion:

Suprascapular neuropathy diagnosis is based on a careful history and a thorough clinical and radiological examination. The purpose of this article is to describe the anatomy of the suprascapular nerve, to define the pathophysiology of suprascapular neuropathy and to present methodically the current diagnostic and treatment strategies.

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.

Suprascapular nerve injury: A cause to consider in shoulder pain and dysfunction

Suprascapular nerve injury is increasingly being recognized as an important cause of shoulder dysfunction. The non-specific clinical features of suprascapular nerve injury can make diagnosis difficult. However, it is essential for clinicians to consider it as part of the differential diagnoses in patients with vague pain or sensory disturbances over the posterosuperior part of their shoulder or have unexplained atrophy and weakness of their supraspinatus or infraspinatus muscle. Electrodiagnostic studies are useful in confirming and localising the nerve injury, while MRIs can be employed to determine the cause of nerve injury and assess the integrity of the rotator cuff muscles. Isolated suprascapular nerve injury can be managed with a trial of conservative management for at least 6 months. Subsequently, decompression of the nerve through open or arthroscopic techniques can be considered - both are associated with high rates of pain relief and functional improvement.

An alternative endoscopic portal for suprascapular nerve approach: an anatomic study

PURPOSE

Arthroscopic approaches have been less preferred than open techniques for treating suprascapular nerve entrapment, possibly because current arthroscopic portals are based on distances to reference points, resulting in discrepancies from differing shoulder sizes. This study reports a portal placement based on proportions rather than absolute length.

METHODS

Open dissection (12 left shoulders) and arthroscopy (12 contralateral shoulders) of the suprascapular notch were performed. In left shoulders, the posterolateral prominence of the acromion, the T1 spinous process, and the suprascapular notch were marked (K-wires). Distances from the posterolateral prominence of the acromion to the suprascapular notch and to the T1 spinous process were measured, and the proportion of those distances (distance to the suprascapular notch/distance to the T1 spinous process) was calculated to indicate the portal's location. In right shoulders, arthroscopy anatomically assessed that proportion's reliability.

RESULTS

Median distances from the posterolateral prominence of the acromion to the T1 spinous process and to the suprascapular notch were 175.7 mm (average 180.4, SD 11.8 mm) and 72.3 mm (average 73.9, SD 4.9), respectively. The medians of the proportions of the defined distances were 40.9 % (range 40-42 %) and 41 % (range 39.3-42.1 %), respectively.

CONCLUSION

Locating the portal at the lateral, 41 % of the distance between the posterolateral prominence of the acromion and the T1 spinous process was accurate and reproducible for suprascapular notch visualization. Clinically, this portal seems to eliminate perioperative morbidity by reducing excessive soft-tissue dissection with a shorter arthroscopic route and avoiding the ligamentous damage.

The effect of infraspinatus hypotrophy and weakness on the arthroscopic treatment of spinoglenoid notch cyst associated with superior labrum anterior-to-posterior lesions

PURPOSE

Patients with spinoglenoid notch cyst associated with superior labrum anterior-to-posterior (SLAP) lesions were evaluated. The patients were all treated by arthroscopic cyst decompression combined with SLAP repair. The hypothesis of the study was that the patients who underwent prolonged conservative treatment period prior to surgery would exhibit significant infraspinatus hypotrophy and weakness, and their postoperative clinical and functional outcomes would be less satisfactory.

METHODS

Sixteen patients exhibited positive MRI and EMG findings with clinical signs of weakness and pain. The median age was 40.5 years (range 32-52), and the study group consisted of 11 males and 5 females with a median follow-up period of 26 months (12-48). The median duration of symptoms and conservative treatment prior to the surgical intervention was 3.5 months (1-14). Seven patients in group A exhibited infraspinatus hypotrophy. Group B comprised 9 patients without infraspinatus hypotrophy.

RESULTS

The results of the pre- and postoperative Constant scores, visual analogue scale (VAS) scores, and external rotation strength test rates were compared between groups. They all improved in terms of pain, strength, and function (P < 0.05). Significant differences were observed between the pre- and postoperative external rotation strengths and Constant scores (P < 0.05). However, no significant difference was observed between the pre- and postoperative VAS scores (n.s.). A significant correlation was observed in group A between surgical timing, the preoperative external rotation strength ratio (P = 0.04) and the postoperative VAS scores (P = 0.013).

CONCLUSION

The arthroscopic treatment was satisfactory with good clinical outcomes. Infraspinatus hypotrophy occurred in cases of prolonged surgical duration and significantly affected external rotation strength and functional outcomes.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

Compression and entrapment neuropathies

Peripheral nerve entrapments are frequent. They usually appear in anatomical tunnels such as the carpal tunnel. Nerve compressions may be due to external pressure such as the fibular nerve at the fibular head. Malignant or benign tumors may also damage the nerve. For each nerve from the upper and lower limbs, detailed clinical, electrophysiological, imaging, and therapeutic aspects are described. In the upper limbs, carpal tunnel syndrome and ulnar neuropathy at the elbow are the most frequent manifestations; the radial nerve is less frequently involved. Other nerves may occasionally be damaged and these are described also. In the lower limbs, the fibular nerve is most frequently involved, usually at the fibular head by external compression. Other nerves may also be involved and are therefore described. The clinical and electrophysiological examination are very important for the diagnosis, but imaging is also of great use. Treatments available for each nerve disease are discussed.

Suprascapular nerve: is it important in cuff pathology?

Suprascapular nerve and rotator cuff function are intimately connected. The incidence of suprascapular neuropathy has been increasing due to improved understanding of the disease entity and detection methods. The nerve dysfunction often results from a traction injury or compression, and a common cause is increased tension on the nerve from retracted rotator cuff tears. Suprascapular neuropathy should be considered as a diagnosis if patients exhibit posterosuperior shoulder pain, atrophy or weakness of supraspinatus and infraspinatus without rotator cuff tear, or massive rotator cuff with retraction. Magnetic resonance imaging and electromyography studies are indicated to evaluate the rotator cuff and function of the nerve. Fluoroscopically guided injections to the suprascapular notch can also be considered as a diagnostic option. Nonoperative treatment of suprascapular neuropathy can be successful, but in the recent decade there is increasing evidence espousing the success of surgical treatment, in particular arthroscopic suprascapular nerve decompression. There is often reliable improvement in shoulder pain, but muscle atrophy recovery is less predictable. More clinical data are needed to determine the role of rotator cuff repair and nerve decompression in the same setting.

Suprascapular nerve block: a narrative review

Suprascapular nerve blockade (SSNB) is a simple and safe technique for providing relief from various types of shoulder pain, including rheumatologic disorders, cancer, and trauma pain, and postoperative pain due to shoulder arthroscopy. Posterior, superior, and anterior approaches may be used, the most common being the posterior. Recently, an ultrasound-guided approach has been described. In this review, the basic anatomy of the suprascapular nerve will be described. The different techniques of SSNB and indications for SSNB will be discussed. The complications of SSNB and outcomes of SSNB on the management of acute and chronic shoulder pain will be reviewed.

Suprascapular neuropathy: what does the literature show?

Suprascapular neuropathy remains a rare, albeit increasingly recognized, diagnosis. Despite its relatively low prevalence, it must be kept in the shoulder surgeon's mind as a potential cause of shoulder pain, particularly in patients where the history, physical examination, and imaging studies do not adequately explain a patient's symptoms or disability. Although challenging to identify, suprascapular neuropathy can be successfully treated. The current literature shows that the location and mechanism of nerve injury are the most important factors guiding management. Different treatment strategies are required, depending on the specific location and type of nerve injury. Controversy regarding if and when to perform an isolated suprascapular nerve release continues. Furthermore, no recommendations regarding suprascapular nerve release in conjunction with rotator cuff repair can be made at this time, and further research is necessary to better delineate the indications in the future.

Muscle degeneration in rotator cuff tears

Rotator cuff tears are among the most common injuries seen by orthopedic surgeons. Although small- and medium-sized tears do well after arthroscopic and open repair, large and massive tears have been shown to develop marked muscle atrophy and fatty infiltration within the rotator cuff muscles. These pathologic changes have been found to be independent predictors of failed surgical repair with poor functional outcomes. To understand the pathophysiology of rotator cuff disease, we must first develop an understanding of the changes that occur within the cuff muscles themselves. The purpose of this review is to summarize the molecular pathways behind muscular degeneration and emphasize new findings related to the clinical relevance of muscle atrophy and fatty infiltration seen with rotator cuff tears. Understanding these molecular pathways will help guide further research and treatment options that can aim to alter expression of these pathways and improve outcomes after surgical repair of massive rotator cuff tears.

Suprascapular neuropathy: diagnosis and management

Although historically considered a diagnosis of exclusion, suprascapular neuropathy may be more common than once believed, as more recent reports are describing the condition as a cause of substantial pain and weakness in patients with and without concomitant shoulder pathology. The etiology is traction or compression of the suprascapular nerve. This can result from a space-occupying lesion, such as a ganglion cyst, or a traction injury as a result of repetitive overhead activities. More recent studies have cited cases of traction injuries occurring with retraction of a large rotator cuff tear. Atrophy of the infraspinatus and/or supraspinatus rotator cuff muscles with resultant weakness in forward flexion and/or external rotation of the shoulder on physical examination may be demonstrated. Magnetic resonance imaging (MRI) is the preferred modality to assess atrophy of the rotator cuff muscles as well as assess potential causes of suprascapular nerve compression. Electromyography and nerve conduction velocity studies remain the gold standard for confirmation of the diagnosis of suprascapular neuropathy; however, nerve pain may occur even in the setting of a negative electromyography. Initial management is usually nonoperative, consisting of activity modification, physical therapy, and nonsteroidal anti-inflammatory drugs. Surgical intervention is considered for patients with nerve compression by an external source or for symptoms refractory to conservative measures. Decompression of the suprascapular nerve may be accomplished through an open approach, although arthroscopic surgical approaches have become more common in the past several years.

Clinical outcomes of suprascapular nerve decompression

BACKGROUND

While the incidence and prevalence of suprascapular neuropathy (SSN) remains largely unknown, the evaluation and treatment of SSN appears to be increasing. Despite multiple technique articles demonstrating nerve decompression, there has been no clinical evidence to support the efficacy of SSN decompression in the absence of rotator cuff disease.

METHODS

Between October 2006 and February 2010, 27 patients underwent arthroscopic suprascapular nerve decompression at the suprascapular and/or spinoglenoid notch. Eighty-nine percent (24/27) of patients had preoperative positive electromyography and nerve conduction EMG/NCV studies documenting suprascapular nerve pathology. All patients had either a computed tomography (CT) arthrogram or magnetic resonance imaging (MRI) documenting rotator cuff integrity. All patients were evaluated with pre and postoperative subjective shoulder values (SSV) and American Shoulder and Elbow Society (ASES) self-assessment scores. Additionally, patients were questioned whether they would have the procedure again and approximately at what week they experienced noticeable pain relief.

RESULTS

The 27 patients were followed for an average of 22.5 months (range, 3-44). Three patients were lost to follow-up. Seventy-one percent (17/24) of patients reported pain relief (VAS [Visual Analogue Scales] pain scale) that was statistically significant (P = .0001) at an average of 9.4 weeks from surgery. Seventy-five percent (18/24) and 71% (17/24) had statistically significant improvement in ASES (P = .0001) and SSV scores (P = .0014), respectively. Seventy-one percent (17/24) would have the surgery again.

CONCLUSION

The present study demonstrates a large series of patients treated for SSN without rotator cuff pathology. Our results show statistically significant improvement in VAS, ASES, and SSV.

[Nerve compression syndrome of the shoulder : Arthroscopic decompression procedures]

Several nerve compression syndromes have been described in the literature involving compression of the axillary nerve in the quadrangular space and most importantly compression of the suprascapular nerve in the suprascapular as well as the spinoglenoid notch. This article describes the arthroscopic techniques of nerve decompression around the shoulder.

Suprascapular neuropathy

Suprascapular neuropathy has often been overlooked as a source of shoulder pain. The condition may be more common than once thought as it is being diagnosed more frequently. Etiologies for suprascapular neuropathy may include repetitive overhead activities, traction from a rotator cuff tear, and compression from a space-occupying lesion at the suprascapular or spinoglenoid notch. Magnetic resonance imaging is useful for visualizing space-occupying lesions, other pathological entities of the shoulder, and fatty infiltration of the rotator cuff. Electromyography and nerve conduction velocity studies remain the standard for diagnosis of suprascapular neuropathy; however, data on interobserver reliability are limited. Initial treatment of isolated suprascapular neuropathy is typically nonoperative, consisting of physical therapy, nonsteroidal anti-inflammatory drugs, and activity modification; however, open or arthroscopic operative intervention is warranted when there is extrinsic nerve compression or progressive pain and/or weakness. More clinical data are needed to determine if treatment of the primary offending etiology in cases of traction from a rotator cuff tear or compression from a cyst secondary to a labral tear is sufficient or whether concomitant decompression of the nerve is warranted for management of the neuropathy.

Suprascapular neuropathy

Suprascapular neuropathy is a relatively uncommon but significant cause of shoulder pain and dysfunction. The suprascapular nerve follows a tortuous course from the neck to the posterior shoulder. There are several potential causes of nerve entrapment along this path, particularly at the vulnerable suprascapular and spinoglenoid notches, where nerve excursion is limited by bony and ligamentous constraints. Additional extrinsic compression may be caused by glenohumeral joint-related ganglion cysts or soft-tissue masses. Traction neuropathy may occur following excessive nerve excursion during overhead sports or as a result of massive, retracted rotator cuff tears in older patients. Diagnosis is based on a careful history, physical examination, focused imaging, and electrodiagnostic studies. In the absence of a clear structural compression or overtensioning of the nerve, treatment initially should be nonsurgical, with activity modification and physical therapy. Discrete nerve compression or failure of nonsurgical measures warrants early surgical intervention. Arthroscopic alternatives to the traditional open suprascapular and/or spinoglenoid notch decompressions have the benefit of simultaneously diagnosing and addressing intra-articular and/or subacromial pathology while minimizing morbidity. In most patients, both open and arthroscopic approaches provide reliable pain relief and improvements in function; return of strength and muscle bulk is less predictable.

The shoulders of professional beach volleyball players: high prevalence of infraspinatus muscle atrophy

BACKGROUND

Beach volleyball is an Olympic overhead sport. It is not well known which clinical and imaging findings are normal and which are associated with symptoms.

HYPOTHESIS

There are typical clinical and imaging findings in the hitting shoulders of fully competitive professional beach volleyball players, as compared with their nonhitting shoulders.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

During the Beach Volleyball Grand Slam Tournament in Klagenfurt, Austria, 84 professional players (54 men, 30 women) underwent a questionnaire-based interview and a complete physical examination, including scoring and sonography of both shoulders. Twenty-nine players had shoulder MRIs.

RESULTS

The mean age of the athletes was 28 years. Atrophy of the infraspinatus muscle was found in 30% of the hitting shoulders, and it was not typically recognized by the players. The absolute Constant score was significantly lower in the hitting shoulder (87 versus 93 points, P < .0001). Average external rotation strength was decreased in the hitting shoulder (8.2 versus 9.5 kg, P < .0001). There were more abnormalities on the sonography of the hitting shoulder (1.7 versus 0.4, P < .0001) and in the same shoulders on MRI than on sonography (P = .0231). Compression of the suprascapular nerve was not observed. Pain in the hitting shoulder was present in 63% of the players, without clear correlations to the investigated clinical and imaging parameters.

CONCLUSION

The prevalence of infraspinatus muscle atrophy in professional beach volleyball players is 30%. The typical, fully competitive player has subjectively unrecognized decreased strength of external rotation and frequent unspecific shoulder pain. Therefore, abnormal clinical and imaging findings in the beach volleyball player should be interpreted with care.

Suprascapular Nerve Neuropathy Secondary to Spinoglenoid Notch Ganglion Cyst: Case Reports and Review of Literature

Introduction: Suprascapular nerve neuropathy secondary to ganglion cyst impingement has increasingly been found to be a cause of shoulder pain. Clinical Picture: We present 2 patients who complained of dull, poorly localised shoulder pain, which worsened with overhead activities. Magnetic resonance imaging showed ganglion cysts in the spinoglenoid notch. Treatment: Both patients failed conservative management with physiotherapy and underwent shoulder arthroscopy. One patient underwent arthroscopic decompression of the cyst and the other had open excision of the cyst. Outcome: Both patients experienced resolution of symptoms within 6 months of surgery. Conclusion: With appropriate treatment, suprascapular nerve neuropathy secondary to ganglion cyst impingement is a treatable condition with potentially good results. Key words: Impingement, Shoulder

Neurovascular injuries to the athlete's shoulder: part II

Athletes are at particular risk of compromise of the neurovascular structures of the shoulder-specifically, neurovascular conditions distal to the brachial plexus. These conditions include thoracic outlet syndrome, axillary artery occlusion, effort thrombosis, suprascapular nerve entrapment, quadrilateral space syndrome, and complex regional pain syndrome. When diagnosed properly and in a timely fashion, function of the limb can be preserved. To accomplish this, the physician must possess a detailed understanding of the various clinical presentations, diagnostic techniques, and treatment options.

Nerve injury about the shoulder in athletes, part 1: suprascapular nerve and axillary nerve

Nerve injuries about the shoulder in athletes are being recognized with increasing frequency. Prompt and correct diagnosis of these injuries is important to treat the patient and to understand the potential complications and natural history so as to appropriately counsel athletes. This 2-part article is a review and an overview of the current state of knowledge regarding some of the more common nerve injuries seen about the shoulder in athletes.

Diagnosing Suprascapular Neuropathy in Patients With Shoulder Dysfunction: A Report of 5 Cases

Background and Purpose. Suprascapular neuropathy, resulting in shoulder pain and weakness, is frequently misdiagnosed. The consequences of misdiagnosis can include inappropriate physical rehabilitation or surgical procedures. The purpose of this case report is to describe the differential diagnosis of suprascapular neuropathy. Case Descriptions. Five patients were initially diagnosed with subacromial impingement syndrome and referred for physical therapy. Physical therapist examination findings were consistent with subacromial impingement syndrome and suprascapular neuropathy. Subsequent electrophysiologic testing confirmed the diagnosis of suprascapular neuropathy in all 5 patients. Discussion. The differential diagnosis of patients with suprascapular neuropathy includes subacromial impingement syndrome, rotator cuff pathology, C5–6 radiculopathy, and upper trunk brachial plexopathy. The diagnostic process and a table with key findings based on evidence and clinical experience is presented for differential diagnosis.

Ganglion cysts of the shoulder: technique of arthroscopic decompression and fixation of associated type II superior labral anterior to posterior lesions

Ganglion cysts of the shoulder and concomitant suprascapular nerve compression should be considered in the differential diagnosis of shoulder pain. They are associated commonly with labral tears, most commonly SLAP lesions. MRI has become commonplace in evaluating shoulder pain and has led to the increased awareness of shoulder cysts. MRI accurately demonstrates the size and location of ganglions, which is critical when planning surgical intervention. It also has shown the frequent association of intra-articular pathology with these cysts. Despite that MRI can detect atrophy, the diagnosis of suprascapular nerve compression can be confirmed only by EMG/NCS, because the presence of a cyst does not necessarily mean the nerve is compressed. Likewise, a positive EMG does not confirm that the compression is caused by a ganglion cyst. EMG/NCVs are necessary for confirming the diagnosis and evaluating nerve and muscle function. A trial of nonoperative management is warranted; however, this is associated with a high failure rate. Aspiration techniques are successful for decompression of the cysts and initial pain relief; however, the intra-articular pathology is not addressed and there is a higher rate of recurrence. Open resection of the ganglion cyst is successful; however, the intra-articular labral tears are not addressed, which can lead to recurrence and the morbidity of the cyst excision is not warranted. Shoulder arthroscopy has led to the identification of associated intra-articular pathology such as SLAP lesions. These were not appreciated previously with open surgery and therefore were not addressed. Arthroscopic techniques have evolved to allow decompression of the ganglion cysts and repair of the labral lesions. This should decrease the possibility of recurrence of the cyst by eliminating the cyst and the pathologic lesion that created it. Arthroscopic excision also avoids much of the morbidity of the open approach and allows intra-articular pathology to be addressed concomitantly. This point has been emphasized by other investigators also. Furthermore, because of the limited surgical dissection, rehabilitation is able to begin earlier, with less patient discomfort and more prompt return to normal activities.

Shoulder Numbness in a Patient with Suprascapular Nerve Entrapment Syndrome: Cutaneous Branch of the Suprascapular Nerve: Case Report

OBJECTIVE AND IMPORTANCE

The ability to diagnose peripheral nerve disorders is dependent on knowledge of the anatomic course and function of the nerves in question. The classic teaching regarding the suprascapular nerve (SScN) is that it has no cutaneous branches, despite the fact that a cutaneous branch was first reported in the anatomic literature 20 years ago.

CLINICAL PRESENTATION

We describe a case of a 35-year-old male patient who presented with right shoulder pain and atrophy and weakness of the right supra- and infraspinatus muscles. During the examination, he was also noted to have an area of numbness involving the right upper lateral shoulder region. Electrical study results were consistent with SScN entrapment at the suprascapular notch.

INTERVENTION

The patient underwent surgical decompression 7 months after the onset of his symptoms. The patient noted resolution of his shoulder pain immediately after the procedure, and his shoulder sensory disturbance had improved by 2 weeks. At 9 months after surgery, he remained pain-free, his shoulder sensation was normal, and his motor abnormalities had improved significantly.

CONCLUSION

This case provides clinical evidence for the presence of a cutaneous branch of the SScN, as described in cadaveric studies. Although shoulder numbness demands a search for alternative diagnoses, it does not necessarily exclude the diagnosis of SScN entrapment.

Injuries to the shoulder in the throwing athlete. Part two: evaluation/treatment

In part one of this three-part series (March/April 2000), I concentrated on summarizing the biomechanics of the normal throwing shoulder and the pathophysiology of injury. A classification of injury was presented that was based on the principles contained in that article. Part two of this series will focus on the evaluation and treatment of injuries, expanded from an understanding of the principles learned in part one. The ability to perform a skillful examination, and thus develop an accurate diagnosis, is the foundation for treatment. Fortunately, many difficulties encountered in a thrower's shoulder can be treated with a nonoperative approach. However, in instances where conservative measures fail, an improved understanding of the pathophysiology of injury and the development of improved surgical techniques are leading to more accurate diagnoses and more successful rates of return of the athlete to a premorbid level of activity.