Suprascapular Neuropathy in Overhead Athletes

Supra shoulder blader Neuropathy in Overhead AthletesSUPRASCAPULAR NEUROPATHY IN OVERHEAD ATHLETES A SYSTEMATIC recapitulation ON AETIOLOGY AND TREATMENT OPTIONSSurya.P, Pankhania. R, Funk.LABSTRACTSuprascapular neuropathy is a great deal overlooked as a cause for elevate upset in overhead athletes. However, with recent advancements in the understanding of the bod as well as its treatment methods, suprascapular neuropathy is now diagnosed to a greater extent frequently. Consistent overhead activities, rotator cuff tear and direct compression of the impudence, by space occupying lesion are important etiologies for suprascapular neuropathy. While MRI is widely used to identify space-occupying lesions and rotator cuff tarnish Electromyography (EMG) and case Conduction Velocity (NCV) remains cash banals for confirming blot to the bosom. Conservative tangible therapy, nerve blocks and arthroscopic and apply operative interjections are the main treatment plans for suprasca pular neuropathy.1. INTRODUCTION AND BACKGROUNDThe posterosuperior aspect of elevate receives its sensory(prenominal) innervation from the suprascapular nerve. The suprascapular nerve also provides motor innervation to supraspinatus and infraspinatus musclemans. Compression or clutches of nerve and rotator cuff diseases are run aground to be associated with suprascapular nerve disability and neuropathy. Clinical symptoms of the condition include injure in the rump shoulder, feeble forward flexion, and weak external rotation. It is also noteworthy that the multiple presentations for suprascapular nerve neuropathy turn greatly in different patients and then diagnosis of the condition is frequently challenging. This kind of nerve damage is a less common reason for shoulder pain and dysfunction in the general population, however is widely observed in athletes who play overhead sports much(prenominal) as volleyball game game, tennis, badminton, and baseball. Such sports exp ose the athletes give to overhead, abducted and externally rotated positions for prolonged periods of time. (Cummins Schneider, 2008).Observational studies have identified that players involved in overhead sports are at higher risk of injuries related to apply of the shoulder such as rotator cuff tendinopathy and tearing of glenoid labrum (Pillai et al. 2011). On the other hand, shoulder pain callable to suprascapular neuropathy is observed in only 1-2% of cases and therefore, the condition is often overlooked during diagnosis for shoulder pain (Boykin et al. 2010). Among the overhead sports athletes, incidences of suprascapular neuropathy are maximum in volleyball players. Around 33% of volleyball players suffer from this condition at some instance in their career (Boykin et al. 2010).Traditionally, suprascapular neuropathy has always been regarded as a diagnosis of exclusion. However, now with further understanding of the etiology and advanced diagnostic options, the condition is being recognised by physicians from an earlier onset.2. AETIOLOGY FOR SUPRASCAPULAR NEUROPATHYRotator cuff tear is considered as a prime cause for suprascapular neuropathy. Studies show that suprascapular neuropathy place also part secondary to traction and microtrauma, especially in overhead athletes, particularly due to tightening of the spinoglenoid ligament during the overhead throwing position. The risk for the development of suprascapular neuropathy also increases in patients with ossification of the crosswise scapular ligament or spinoglenoid ligament. Other causes such as compression of the nerve at spinoglenoid notch due to the presence of a b whizz tumor, cyst due to labral, soft tissue or capsular injury tissue can also lead to the condition. Suprascapular neuropathy is also rarely seen following brachial neuritis, glenohumeral dislocation, fracture of the shoulder girdle, and penetrating or iatrogenic injury to the nerve (Lewis et al. 2012).All these etiological factors for suprascapular neuropathy are discussed in detail in the following section.2.1 Rotator Cuff InjuryAnatomically, the suprascapular nerve branches from the upper trunk of the brachial plexus. From there, it travels posterior to the clavicle, passes below the transverse scapular ligament and then enters the suprascapular notch. The motor branches innervate the supraspinatus, and the nerve continues past the spinoglenoid notch and innervates the infraspinatus. Injury due to traction or compression of the nerve at any point in this path can lead to suprascapular neuropathy. Retracted superior or posterior rotator cuff tear is the most common cause for suprascapular nerve traction injury. Tension on the suprascapular nerve lying at a suprascapular notch or spinoglenoid notch increases with the retraction of supraspinatus and infraspinatus tendons. Studies on cadavers by Gosk et al (2007) showed that as the retraction of supraspinatus tendon increases, it reduces the angle betwe en the suprascapular nerve and its first motor branch, which leads to an increase in focus and thus causes traction injury. Gosk et al. (2007) also be that battalionive rotator cuff tear was the main reason for suprascapular neuropathy in eight different overhead players. On the other hand, studies by Lajtai et al. (2009) be that rotator cuff tear and muscle atrophy were responsible for only 8% of suprascapular neuropathy cases.Expanding the knowledge on the topic, different studies also showed that the tension between rotator cuff, supraspinatus and infraspinatus tendons has a profound impact on the condition of the suprascapular nerve. Observations of cadaver showed that the tension on the neurovascular pedicle increases significantly once the lateral advancement of a retracted rotator cuff tear exceeds 3 cm (Greiner et al. 2003). Other studies advert that if the rotator cuff extension increases by 3 cm, it lay significant tension on the motor branches of the suprascapular ne rve. Also, the tension on the medial portion of the suprascapular nerve starts to increase only by 1 cm extension of the rotator cuff. Increased tension is one of the important reasons for traction injury to the nerve (Larissa et al. 2014).It has also been reported that following surgical repair of rotator cuff tear, the tendons can be advanced up to 3.5 cm without any significant risk to the health of suprascapular nerve. Various reports suggest that surgical repair of rotator cuff tear can help in either partially or completely resolving suprascapular neuropathy. Nerve reco truly by reinnervation has been found in patients of suprascapular neuropathy following partial or complete arthroscopic rotator cuff repair (Petra et al. 2013).2.2 Nerve injury Sports Specific EtiologySports physiotherapists have proposed various etiological mechanisms for suprascapular neuropathy which includes repeated traction, microtrauma, ischaemia of the nerve and compression of the nerve by soft tissue, tumor or cyst. However, the majority of the healthcare professionals consider that nerve injury due to repetitive trauma is the main reason for the development of suprascapular neuropathy.Two main sites for suprascapular nerve injury are the suprascapular notch and the spinoglenoid notch. The symptoms alongside clinical presentation for suprascapular neuropathy thus depend on the location of nerve injury. Injury of suprascapular nerve at the spinoglenoid notch has been found to cause detached atrophy and weakness of the infraspinatus muscle. This condition is also known as infraspinatus syndrome. A systematic literature review by Lee et al. (2007) found that suprascapular neuropathy due to infraspinatus syndrome is common in overhead game athletes, particularly volleyball players. (https//www.shoulderdoc.co.uk/article/1250)One important reason for traction injury in volleyball players is the huge amount of motion go byring at the shoulder during throwing action. The role of the s capula in allowing throwing motion as well as other overhead sports military action is now well-researched. It has been observed that the movement of the scapula during the protraction and retraction of hands leads to significant trauma of suprascapular nerve at both the suprascapular and spinoglenoid notches. This phenomenon is known as the sling effect. The sling effect proposes that certain positioning of upper limb during overhead activity exposes the suprascapular nerve at the suprascapular notch to a significant amount of holy stress and thus injury. Sling effect also suggests that the suprascapular nerve is exposed to high risk of traction injury when it bends around the spine of the scapula at the spinoglenoid notch (Arash et al. 2015).Chronic overuse of shoulder, as well as functional instability, may cause the suprascapular nerve to angle sharply at the spinoglenoid notch, as an adaptive response. This condition is known as SICK scapula which is an abbreviation to Scapu lar protraction, Inferior border prominence, Coracoid tightness, and Kinesis abnormalities of the scapula (Burkhart et al. 2003). While imaging for the shoulder injuries of volleyball players, Crema Murakami (2016) found that SICK scapula significantly contributes to increased tension on the suprascapular nerve and thus causes traumatic injury.https//www.shoulderdoc.co.uk/article/930 http//www.scielo.brThe spinoglenoid ligament lays into the posterior glenohumeral capsule. Observations suggest that the ligament gets stretched and rigid with the abduction and inhering rotation of the ipsilateral upper limb across the body. Such action leads to the traction of suprascapular nerve at the spinoglenoid notch (Crema Murakani, 2016).Sandow Ilic (1998) provided another proposal for traumatic injury to the suprascapular nerve. agree to them, when the upper limb is abducted and externally rotated, the medial border of the spinatus tendon present at the spinoglenoid notch compresses the s uprascapular nerve. Repeated upper limb action thus causes trauma to the nerve and injures it. Plancher Petterson (2016), recently supported this mechanism of nerve injury in their research paper.The injury to the posterior part of the suprascapular nerve is thought to occur due to multiple, abrupt, peculiar stretching of infraspinatus tendon during the deceleration phase of the floater serve (the most common type of overhead volleyball serve). Ferretti observed such injury in volleyball players while Arash et al. (2016) observed this in various overhead sports players as well as labourers.2.3 Other etiologies Nerve compression According to Raddic Wallace (2016) direct compression of suprascapular nerve passing through spinoglenoid notch can occur due to ganglionic cysts arising from the glenohumeral joint. Such cysts are formed by synovial bland leakage due to injury to the posterior glenoid labrum. Incidences of suprascapular nerve compression due to a bone tumor or the surroun ding soft tissues are very rare but not absent.Nerve ischaemia In very rare conditions, microemboli formed after any trauma gets trapped in the suprascapular artery and then migrate to the vasa nervorum thus hindering the blood and fluid supply to the suprascapular nerve. This leads to nerve ischemia and then neuropathy (Shin et al. 2016).3. PRESENTATION DIAGNOSIS OF SUPRASCAPULAR NEUROPATHYThe peculiar clinical presentations of suprascapular neuropathy are as follows get up pain which worsens on cross body abduction or internal rotation of ipsilateral muscle.Atrophy of supraspinatus or/and infraspinatus muscle, observable on physical mental test.The weakness of ipsilateral shoulder abduction observed during manual muscle testing.The weakness of external rotation of shoulder observed during manual muscle testing.Pain create by pressure application over the suprascapular and spinoglenoid notch.The tenderness between the clavicle and the spine of the scapula or deep and posterior to the acromioclavicular joint (Podgorski et al. 2014).Radiological examination using X-rays is the first step for diagnosis if suprascapular neuropathy is suspected. It is important to have a radiological view of a suprascapular notch and spinoglenoid notch along with a standard view of the shoulder area. However, no remarkable changes can be observed in the radiological images unless is a prominent trauma responsible for the condition. MRI of the shoulder helps in identifying muscle oedema, muscle atrophy, and ganglionic cyst, if present. These factors are responsible for suprascapular neuropathy due to direct compression. Three Tesla (3-T) MRI scan is another tool used in the diagnosis of suprascapular neuropathy as it helps to identify any nerve abnormality or any denervation changes in muscles. Ultrasound is also appliable for the diagnosis of cysts and other muscle abnormalities as it is an loud and relatively accurate diagnostic tool (Ahlawat et al. 2015).Electrodiagnostic s tudies are gaining increasing popularity as an important diagnostic tool for suprascapular neuropathy. Positive sharp waves and fibrillation potentials indicated by electromyography can suggest denervation while polyphasic motor unit action potentials suggest motor innervation abnormalities. Larisa et al (2014) suggest that electromyography (EMG) and nerve conduction velocity (NCV) tests are the gold standards for the contracting of suprascapular nerve injury. EMG and NCV are suggested in the following conditionsConsistent pain on the back upper side of the shoulder and no confirm diagnosis is found.Atrophy as well as the weakness of supraspinatus and infraspinatus tendons in the absence of rotator cuff injury.MRI observations show muscle edema.Massive rotator cuff tendons with retraction and traction on the nerve.There are published and examined normative values for electrodiagnostic studies. According to which, the normal distal motor latencies to the supraspinatus muscles during stimulation at the Erb point are 2.7 msec 0.5 and to the infraspinatus muscles, 3.3 msec 0.5. Side-to-side differences greater than 0.4 msec suggest focal entrapment of the SSN or another neural injury (Larisa et al. 2014).In some cases, where outcomes of these electrodiagnostic studies are negative or not specific fluoroscopically guided local anesthetic injection is used. This injection is administered to the region of suprascapular nerve and related pain relief is evaluated. This method is very rough-and-ready in confirming the involvement of suprascapular nerve injury in shoulder pain (Debbie et al. 2014).4. TREATMENT MODALITIES FOR SUPRASCAPULAR NEUROPATHYTreatment for suprascapular neuropathy is selected on the basis of different factors like etiology of nerve damage, the severity of nerve damage, duration of pain and weakness in shoulder, degree of functional disability and patients choice. The three main types of treatment options are traditionalist physical therapy, ne rve blocks and surgical repair.4.1 Physical therapy If the suprascapular neuropathy is caused due to rotator cuff tear or labral tear with paralabral cyst, the treatment selection is done with regards to the pathology. However, in the case of disjointed nerve injury, the conservative treatment plan including activity modification, analgesic drugs, and conservative physical therapy is initiated. The patient is asked to avoid or stop overhead activity as soon as he/she is diagnosed with suprascapular neuropathy. Following which, a physical therapy program is initiated which focuses on the movement of shoulder and muscle strengthening. The therapy also includes scapular stabilisation (Trojian, 2015). varied studies on patients with isolated suprascapular neuropathy suggest that non operative treatment for 6 months to 1 year provides good to excellent outcomes in the majority of the patients while surgical disturbance following physical therapy is required by only 20% patients (Lee et al. 2007). Boykin et al (2010) suggest that such non-operative treatments in the case of suprascapular neuropathy due to compression by mass or a cyst do not provide satisfactory results. It has been found that 53% of patients with suprascapular neuropathy due to spinoglenoid cyst get significant pain confine and symptomatic relief with non-operative methods while 96% of such patients experienced positive outcomes with surgical treatment.4.2 Surgical TreatmentIn case the conservative physical therapy for isolated suprascapular neuropathy fails, the patient is switched to surgical intervention. Furthermore, surgical intervention is immediately offered if suprascapular neuropathy is concomitant to rotator cuff tear or labrum tears with paralabral cysts. However, literature review suggests that there are debates slightly the application of surgical intervention for correcting nerve decompression in case of concomitant pathology. Many researchers recommend only for the correction of the isolated rotator cuff or labral repair and avoid surgery for nerve decompression (Boykin et al. 2010).Nerve damage at the suprascapular notch is usually treated with the release of the transverse ligament by an open or arthroscopic technique. Fewer complications have been observed with the open technique. Patients are reported to have adequate pain management as well as alter muscle strength with the open technique. However, muscle atrophy cannot be reversed in all the cases using this technique. Improvement of supraspinatus muscle strength is observed among 90% of patients treated by open technique while no significant improvement of infraspinatus muscle is seen (Kim et al. 2005). While there are no specific indications for arthroscopic suprascapular nerve decompression, it has been found to be similarly effective in resolving pain. However, extensive data is not available to show the effectiveness of the technique in treating muscle atrophy and weakness (Boykin et al. 2010).N erve damage at spinoglenoid notch is usually secondary to nerve compression by the space-occupying lesion. Surgical management of such lesions often requires open or arthroscopic approach and resection of the lesion. It is noteworthy that patients with suprascapular neuropathy at spinoglenoid notch show poor results with physical therapy alone and thus are suggested to have surgical intervention immediately. Cyst recurrence rates are very low with both the methods (Petra et al. 2013). Literature review suggests that ultrasound-guided paralabral cyst aspiration is a good alternative to surgical intervention for suprascapular neuropathy due to compression at spinoglenoid notch. While the majority of patients reported excellent pain relief with the technique, recurrence rates for cyst are found to be between 75 100% (Moen et al. 2012).4.3 Nerve BlockNerve blocks are non-surgical treatment options for suprascapular neuropathy. Nerve blocks are usually administered to manage shoulder pa in in preoperative setups as well as in the case of painful shoulder conditions like adhesive capsulitis. Diagnostic usage and specificity of nerve blocks are widely debated, but the blocks are used to achieve rapid symptomatic relief so that the patient can properly participate in the refilling physical therapy. Nerve blocks consist of an injection of an anaesthetic mixed with corticosteroid administered to the suprascapular notch (Blum et al. 2013).Newer techniques like radiofrequency ablation of suprascapular nerve or palliative treatment for pain due to suprascapular neuropathy are still under consistent research phase and are not yet widely applied.5. CONCLUSIONThe incidences of suprascapular neuropathy can be more easily recognised now due to increased understanding of the condition and improved diagnostic methods. Overhead athletes presenting with vague posterosuperior shoulder pain, muscle atrophy, weakness of supraspinatus and infraspinatus tendons moldiness be investigate d for suprascapular neuropathy. The condition must also be investigated in all the athletes with rotator cuff tear, due to the high incidence. MRI and EMG are the most trustworthy diagnostic techniques to identify suprascapular neuropathy and rotator cuff health. Recently, fluoroscopically guided injections to the suprascapular notch are also gaining popularity as a diagnostic method for the condition. While conservative physical methods can be applied to treat the isolated suprascapular neuropathy, open or arthroscopic surgical corrections are compulsory to treat suprascapular neuropathy due to rotator cuff tear and cystic compression.REFERENCESAhlawat S, Wadhwa V, Belzberg AJ, Batra K, Chhabra A. (2015) Spectrum of suprascapular nerve lesions normal and abnormal neuromuscular imaging appearances on 3-T MR neurography. AJR Am J Roentgenol. 204 (3), 589-601.Arash A., Michael J., and Felix H. (2015) Suprascapular Nerve Release General Principles. In Elite Techniques in elevate Arth roscopy. Switzerland Springer International Publishing, 271-281.Blum A, Lecocq S, Louis M, Wassel J, Moisei A, Teixeira P. (2013) The nerves around the shoulder. Eur J Radiol., 82(1),2-16.Boykin RE, Friedman DJ, Higgins LD, Warner JJ. (2010) Suprascapular neuropathy. J Bone Joint Surg Am., 92(13), 2348-64.Burkhart SS, Morgan CD, Kibler WB. (2003) The disabled throwing shoulder spectrum of pathology Part III The SICK scapula, scapular dyskinesis, the energising chain, and rehabilitation. Arthroscopy, 19(6), 641-61.Crema M., and Murakami A. (2016) Imaging of volleyball injuries. In Imaging in Sports-Specific Musculoskeletal Injuries. Switzerland Springer International Publishing, 663-695.Cummins CA, Schneider DS. (2008) Peripheral nerve injuries in baseball players. Neurol Clin., 26(1), 195-215.Debbie L., Angel M., William E., Susan V., and Ambrose J. (2014) Optimization and normalization of Technique for Fluoroscopically Guided Suprascapular Nerve Blocks. American journal of Roentge nology, 202(3), 576-584, 2014.Gosk J, Urban M, Rutowski R. (2007) Entrapment of the suprascapular nerve anatomy, etiology, diagnosis, treatment. Ortop Traumatol Rehabil, 9(1), 68-74.Greiner K., Golser M, Wambacher F, Kralinger G, and Sperner T. (2003) The course of the suprascapular nerve in the supraspinatus fossa and its vulnerability in muscle advancement. Journal of Shoulder and Elbow Surgery, 12(3), 256-259.Kim D, Murovic JA, Tiel R, and Kline D. (2005) Management and outcomes of 42 surgical suprascapular nerve injuries and entrapments. Neurosurgery, 57(1), 120-127, 2005.Lajtai G, Pfirrmann CW, Aitzetmller G, Pirkl C, Gerber C, and Jost B. (2009) The shoulders of professional beach volleyball players high prevalence of infraspinatus muscle atrophy. The American Journal of Sports Medicine, 37(7), 1375-1383.Larisa J., Elena J., Marisa J., and Jeffrey A. (2014) Evaluation, Treatment, and Outcomes of Suprascapular Neuropathy A 5-Year Review. PM R, 6(9), 774-80.Lee BC, Yegappan M, Thiagarajan P. (2007) Suprascapular nerve neuropathy secondary to spinoglenoid notch ganglion cyst case reports and review of literature. Ann Acad Med Singapore, 36(12),1032-5.Lewis L., Michael T., Paul Y., and Jon J. (2012) Suprascapular Nerve Is It Important in Cuff Pathology? Advances in Orthopedics, name ID 516985.Moen TC, Babatunde OM, Hsu SH, Ahmad CS, Levine WN. (2012) Suprascapular neuropathy what does the literature show? J Shoulder Elbow Surg., 21(6), 835-46.Petra M, Gaspar S, Sven L, Peter H, and Mathias W. (2013) Results of Arthroscopic Partial Repair of Large Retracted Rotator Cuff Tears. Arthroscopy-The Journal of Arthroscopic and Related Surgery, 29(8), 1275-1282, 2013.Pillai G, Baynes JR, Gladstone J, Flatow EL. (2011) greater strength increase with cyst decompression and SLAP repair than SLAP repair alone. Clin Orthop Relat Res., 469(4), 1056-60.Plancher K., and Petterson S. (2016) Distal Suprascapular Nerve Compression Spinoglenoid Ligament Release. In Elite Techn iques in Shoulder Arthroscopy. Switzerland Springer International Publishing, 283-302.Podgorski M, Miroslaw T, Marcin S, Piotr G, Ludomir S, and Michal P. (2014) New parameters describing morphological variations in the suprascapular notch region as potential predictors of suprascapular nerve entrapment. Bmc Musculoskeletal Disorders, 15.Raddic R Wallace A. (2016) Arthroscopic release and labral repair for central compression of the suprascapular nerve. Shoulder Elbow, 8(1), 32-36.Trojian T. (2015, October 13) Suprascapular Neuropathy. Retrieved from http//emedicine.medscape.com/article/92672-overview