肩袖疾病

Overview

• The majority of rotator cuff disorders are amenable to conservative treatment [1].
• Rotator cuff dysfunction may necessitate surgical treatment [1].
• The major indication for revision rotator cuff repair is the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure [2].
• Rotator cuff injuries are most accurately diagnosed with a combination of cuff- and impingement-specific clinical tests [3].
• Deltoid complications combined with rotator cuff pathology represent a rare but devastating complication with no well-described surgical option [4].
• Treatment of chronic massive rotator cuff tears is challenging, and results are comparatively inferior to those of treating patients with smaller rotator cuff tears [17].
• Shoulder arthroscopy literature remains controversial, with conclusions often unsupported due to bias and limitations [19].
• No clinical guidelines for shoulder arthroscopy are definitive pending higher levels of evidence [19].
• No recommendations regarding suprascapular nerve release in conjunction with rotator cuff repair can be made at this time [22].
• Further research is necessary to better delineate the indications for suprascapular nerve release in conjunction with rotator cuff repair [22].
• Open approaches for rotator cuff repairs continue to have indications in certain circumstances, such as complete rotator cuff tendon avulsion and glenohumeral joint incarceration after high-velocity trauma [23].
• There is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up [26].
• Critical shoulder angle and acromial index do not appear to influence 24-month functional outcomes postoperatively [47].
• Critical shoulder angle and acromial index are not contraindications to arthroscopic rotator cuff repair [47].
• Predictors of pain and functional outcomes after operative treatment for rotator cuff tears can be used to select optimal candidates for operative treatment [54].
• Predictors of pain and functional outcomes after operative treatment for rotator cuff tears can assist with patient education and expectations before treatment [54].
• There were no differences of clinically relevant size between arthroscopic and open rotator cuff surgery in postoperative pain in a comparative series [71].

Anatomy & Pathophysiology

• Understanding the function and pathology surrounding the teres minor is paramount in comprehensive management of patients with shoulder pathology [6].
• A systematic approach to magnetic resonance imaging interpretation of shoulder injuries describes the normal imaging appearance of each anatomical structure, the most useful pulse sequences and imaging planes, and signs of injury [28].
• Imaging is an essential tool for evaluation of patients with shoulder pain, and understanding the extent of an injury with imaging is key to successful management [29].
• Tears of the subscapularis have greater biomechanical consequences than do tears of the infraspinatus [31].
• Dynamic superior migration of the humeral head during abduction occurs in patients with rotator cuff tears, as confirmed by in vivo 3D kinematic analysis [37].
• In massive rotator cuff tears, the pectoralis major and latissimus dorsi muscles are effective in improving glenohumeral kinematics and reducing acromiohumeral pressures [40].
• Biomechanical studies indicate that the long head of the biceps contributes to stability of the glenohumeral joint in all directions, although in vivo studies have not yet established this stabilizing effect or the physiologic load required [46].
• Increasing supraspinatus tendon loading causes a mechanical interaction between the supraspinatus and infraspinatus tendons, paralleling the increase in supraspinatus tendon strain [51].
• The physiopathology of symptomatic anterior instabilities is related to dysfunction of the anterosuperior glenohumeral capsular ligament rather than the inferior glenohumeral ligament [52].
• Additional repair of a partial subscapularis tear combined with a supraspinatus tear did not affect external rotation or glenohumeral kinematics [53].
• Shoulders with rotator cuff tears require considerable compensatory deltoid function to prevent abduction motion loss [57].
• Pain reduction from subacromial injection causes shifts in scapulohumeral rhythm, resulting in increased glenohumeral motion and reduced reliance on scapular rotation [59].
• The clinical evidence to support correction of the critical shoulder angle with lateral acromioplasty is insufficient, and further research is required to demonstrate an association between critical shoulder angle and clinical outcomes before treatment algorithms should be altered [61].
• The critical shoulder angle, posterior acromial height, and posterior acromial tilt do not change significantly over a long-term follow-up of at least 10 years, supporting the hypothesis that these scapular morphologic parameters are stable anthropometric characteristics [62].
• Simulated isolated supraspinatus cord and strap tears significantly reduced shoulder abduction force, with cord tears causing a larger decline than strap tears [63].
• The critical shoulder angle may not be responsible for rotator cuff tears; rather, patient activities throughout several decades could induce both cuff lesions and bone remodeling at the acromial level [66].
• The human scapula has two distinctive characteristics: a lateral orientation of the glenoid cavity and a narrow coraco-acromial arch [73].
• Cervical spine position may cause decreased shoulder rotation strength, meaning clinicians should assess shoulder strength in the position the patient requires to use their shoulder because weakness may be missed in standard testing positions [78].

Classification

• Rotator cuff disorders are recognized and managed conditions among patients with shoulder pain [1].
• Rotator cuff dysfunction may necessitate surgical treatment [1].
• The majority of rotator cuff conditions are amenable to conservative treatment [1].
• The major indication for revision rotator cuff repair is the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure [2].
• Rotator cuff injuries are most accurately diagnosed with a combination of cuff- and impingement-specific clinical tests [3].
• Deltoid complications combined with rotator cuff pathology represent a rare but devastating complication with no well-described surgical option [4].
• Increasing knowledge about rotator cuff syndrome, including better imaging, has facilitated patient treatment for a stable spectrum of rotator cuff pathology [5].
• The application of endoscopic surgery has facilitated patient treatment for a stable spectrum of rotator cuff pathology [5].
• Rotator cuff disease, shoulder instability, and associated lesions are common pathologic conditions of the shoulder involving soft tissues [7].
• In the context of rotator cuff disease, the etiology of anterior shoulder pain with macroscopic changes in the biceps tendon is related to the complex interaction of the tendon and surrounding soft tissues, rather than a single entity [8].
• The Korean Shoulder Scoring System (KSS) is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders [9].
• The acromial morphology classification system is an unreliable method to assess the acromion [14].
• The acromial index shows no association with the presence of rotator cuff disease [14].
• A classification system exists to divide coracoids according to their morphology and relative risk of associated subscapularis tears [30].
• Comparing histopathological data with demographical information allows for the identification of rotator cuff tears at risk of repair failure [50].
• Gene expression in human rotator cuff muscles varied according to tendon injury severity [67].

Clinical Presentation

• Rotator cuff disorders are amenable to conservative treatment in the majority of cases [1].
• Rotator cuff dysfunction may necessitate surgical treatment [1].
• The major indication for revision rotator cuff repair is the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure [2].
• Rotator cuff injuries are most accurately diagnosed with a combination of cuff- and impingement-specific clinical tests [3].
• Deltoid complications combined with rotator cuff pathology represent a rare but devastating complication with no well-described surgical option [4].
• Increasing knowledge about rotator cuff syndrome, including better imaging, has facilitated patient treatment for a stable spectrum of rotator cuff pathology [5].
• The application of endoscopic surgery has facilitated patient treatment for a stable spectrum of rotator cuff pathology [5].
• Understanding the function and pathology surrounding the teres minor is paramount in comprehensive management of the patient with shoulder pathology [6].
• Rotator cuff disease, shoulder instability, and associated lesions are common pathologic conditions of the shoulder involving soft tissues [7].
• In the context of rotator cuff disease, the etiology of anterior shoulder pain with macroscopic changes in the biceps tendon is related to the complex interaction of the tendon and surrounding soft tissues, rather than a single entity [8].
• The Korean Shoulder Scoring System (KSS) is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders [9].
• In one-quarter of patients with painful cuff tears, pain developed in a contralateral asymptomatic cuff tear that resulted in a measurable decline in function within 3 years [10].
• The acromial morphology classification system is an unreliable method to assess the acromion [14].
• The acromial index shows no association with the presence of rotator cuff disease [14].
• Ultrasound is an useful tool for discovering in pre-symptomatic stages subjects that may undergo shoulder symptomatic pathologies [15].
• Rotator cuff injuries in adolescents may be overlooked as a cause of disability, leading to significant delays in diagnosis [32].
• Intratendinous rotator cuff tears are difficult to diagnose preoperatively [34].
• Current physiotherapy practice in relation to rotator cuff disorders is variable [35].
• Current physiotherapy practice in relation to rotator cuff disorders is variable [36].
• The Functional Shoulder Score (FSS) is a patient-reported outcome measure that can easily be incorporated into clinical practice [38].
• The FSS provides a quick, reliable, valid and practical measure for rotator cuff problems [38].

Investigations

• Rotator cuff dysfunction may necessitate surgical treatment [1].
• Rotator cuff injuries are most accurately diagnosed with a combination of cuff- and impingement-specific clinical tests [3].
• Better imaging has facilitated patient treatment for a stable spectrum of rotator cuff pathology [5].
• Ultrasound is an useful tool for discovering subjects in pre-symptomatic stages that may undergo shoulder symptomatic pathologies [15].
• The use of MRI before a trial of conservative management in patients with atraumatic shoulder pain, minimal to no strength deficits on physical examination, and suspected cuff tendinopathy other than full-thickness tears provides negative value in the management of these patients, at both the individual and population level [24].
• A systematic approach to the interpretation of a magnetic resonance examination of the shoulder describes the normal imaging appearance of each anatomical structure, the most useful pulse sequences and imaging planes, and the signs of injury [28].
• Imaging is an essential tool for evaluation of patients with shoulder pain [29].
• Understanding the extent of an injury with imaging is key to successful management [29].
• Most abnormal MRI findings were not different in frequency between symptomatic and asymptomatic shoulders [43].
• MRI and US provide similar assessments of postoperative rotator cuff healing, although US is less sensitive [58].
• Shoulder MRI may be warranted for preoperative planning in the select population of patients with chronic calcific tendinopathy and prolonged refractory pain, although the probability of identifying additional cuff pathology requiring surgical intervention is very low [64].
• Preoperative MRI scans of the shoulder interpreted by orthopaedic surgeons with a systematic approach resulted in improved accuracy in diagnosing subscapularis tendon tears compared with previous studies [65].
• The diagnostic accuracy of US, MRI and MRA in the characterisation of full-thickness rotator cuff tears is high with overall estimates of sensitivity and specificity over 0.90 [68].
• A non-contrast shoulder MRI obtained in the community setting after non-dislocating shoulder trauma has a moderate sensitivity for most intraarticular pathologies when interpreted by musculoskeletal radiologists [70].
• The MRI tendinosis grade is associated with stiffness assessed using sonoelastography in patients with rotator cuff tendinopathy [72].
• Tendinosis severity assessed by preoperative MRI was the only factor associated with failure to heal in patients with partial-thickness and small full-thickness rotator cuff tears [75].
• A 3 T MRI protocol can be applied to evaluate morphological tendon outcomes after different treatment modalities [77].
• Shoulders with a symptomatic rotator cuff tear showed higher radioisotope uptake on bone scintigraphy than those with an asymptomatic tear [79].
• Unenhanced magnetic resonance imaging of the shoulder in asymptomatic high performance throwing athletes reveals abnormalities that may encompass a spectrum of nonclinical findings [80].

Treatment

Non-Operative Management

• The majority of rotator cuff disorders are amenable to conservative treatment [1].
• MRI use before a trial of conservative management in patients with atraumatic shoulder pain, minimal to no strength deficits, and suspected cuff tendinopathy (other than full-thickness tears) provides negative value at both individual and population levels [24].
• Nonoperative treatment is appropriate as initial therapy for partial-thickness rotator cuff tears [42].
• There is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease [33].
• Orthobiologics offer a relatively safe management option for rotator cuff pathology, but evidence is inconclusive for or against its use [45].
• Limited evidence suggests that platelet-rich plasma (PRP) injections may not be beneficial in the short term for the nonoperative treatment of chronic rotator cuff disease [56].
• Subacromial PRP injections produce significantly worse improvement in functional outcomes in patients with partial supraspinatus tears compared to patients with isolated tendinopathy [44].

Operative Management

• Rotator cuff dysfunction may necessitate surgical treatment when conservative options are insufficient [1].
• Early operative treatment appears to be better for rotator cuff tears with a sudden onset of symptoms and poor function to achieve maximal return of shoulder function [18].
• Patients undergoing operative treatment for rotator cuff tears had significantly better pain and functional outcomes compared with patients undergoing nonoperative treatment in a prospective cohort study [76].
• Treatment results for chronic massive rotator cuff tears are comparatively inferior to those for smaller rotator cuff tears [17].
• Open approaches for rotator cuff repairs continue to have indications in certain circumstances, such as complete tendon avulsion and glenohumeral joint incarceration following high-velocity trauma [23].
• Arthroscopic revision rotator cuff repair is indicated for the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure [2].
• Repair of partial- and full-thickness rotator cuff tears using a bioinductive implant shows safety and efficacy at 1-year follow-up [11].
• Arthroscopy is a safe and effective treatment for symptomatic calcific tendonitis of the shoulder, including or excluding patients with rotator cuff tears [48].
• For patients with intact rotator cuffs and calcific tendonitis, needling or extracorporeal shockwave therapy (ESWT) may be beneficial alternatives to arthroscopy in some cases [48].

Arthroscopic Subacromial Decompression (SAD)

• Following nonoperative treatment for at least 6 weeks, SAD is a viable and good surgical option for shoulder impingement with an intact rotator cuff [39].
• SAD without cuff repair appears to be a safe, efficacious, and sustainable procedure for patients with partial rotator cuff tears [41].
• Operative management for partial-thickness tears, including arthroscopic subacromial decompression, is considered when nonoperative treatment fails [42].

Adjunctive Procedures and Implants

• PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair [21].
• Routine arthroscopic suprascapular nerve release (SSNR) is not recommended when treating patients with rotator cuff tear [49].
• No recommendations regarding suprascapular nerve release in conjunction with rotator cuff repair can be made at this time, and further research is necessary [22].

Reverse Total Shoulder Arthroplasty (RTSA)

• Severely impaired deltoid function is a contraindication to RTSA [13].
• An isolated supraspinatus tear is a contraindication to RTSA [13].
• The presence of full active shoulder elevation with a massive rotator cuff tear and arthritis is a contraindication to RTSA [13].

Evidence Quality

• Conclusions in shoulder arthroscopy literature are often unsupported due to bias and limitations, and no clinical guidelines are definitive pending higher levels of evidence [19].

Complications

• Rotator cuff dysfunction may necessitate surgical treatment [1].
• Deltoid complications combined with rotator cuff pathology represent a rare but devastating complication with no well-described surgical option [4].
• In one-quarter of patients with painful cuff tears, pain developed in a contralateral asymptomatic cuff tear that resulted in a measurable decline in function within 3 years [10].
• Arthroscopic rotator cuff repair leads to a structural failure rate of 33% but satisfactory functional results with high patient satisfaction at midterm follow-up [27].

Recovery

• The majority of rotator cuff disorders are amenable to conservative treatment, although rotator cuff dysfunction may necessitate surgical treatment [1].
• Conservative versus surgical management for rotator cuff tears does not result in significantly improved shoulder function (evaluated by CMS) at a 2-year follow-up [12].
• Arthroscopic decompression is not recommended in the treatment of rotator cuff tendinopathy [16].
• The natural history of rotator cuff tendinopathy probably plays a significant role in long-term results [16].
• Arthroscopic acromioplasty significantly improves long-term clinical outcomes up to 2 years for chronic rotator cuff tendinopathy when used with platelet-rich plasma injection [69].
• Patients with rotator cuff disease treated without surgery experience a clinically important change in self-assessed outcome with a 2-point change in the Simple Shoulder Test (SST) score or a 12 to 17-point change in the American Shoulder and Elbow Surgeons (ASES) score [83].
• Younger age, lower BMI, more functional capacity, a shorter symptomatic period, reversible changes on MRI, and higher Constant and ASES scores at the first evaluation are good prognostic factors for the natural course of subacromial impingement syndrome [84].
• In one-quarter of patients with painful cuff tears, pain developed in a contralateral asymptomatic cuff tear that resulted in a measurable decline in function within 3 years [10].
• Early operative treatment appears to be better for rotator cuff tears with a sudden onset of symptoms and poor function to achieve maximal return of shoulder function [18].
• The major indication for revision rotator cuff repair is the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure [2].
• Outcomes after repair of partial- and full-thickness rotator cuff tears using a bioinductive implant show safety and efficacy at 1-year follow-up [11].
• Arthroscopic rotator cuff repair leads to a structural failure rate of 33% but yields satisfactory functional results with high patient satisfaction at midterm follow-up [27].
• Increased age and longer duration of follow-up were associated with lower healing rates after double-row rotator cuff repair [20].
• The 'critical period' for healing following rotator cuff repair, during which risks of retears are high, extends to the first 6 months [85].
• Although functional status improved with time after 6 months, the structural status of repaired cuffs remained unchanged between 6 and 19 months postoperatively [55].
• Improvement in functional outcome after arthroscopic repair of a subscapularis tendon tear is maintained long-term [60].

Key Evidence

• [L4] The majority of conditions are amenable to conservative treatment, although rotator cuff dysfunction may necessitate surgical treatment. [1] (10.1002/art.20668)
• [L5] The major indication for revision rotator cuff repair is the persistence of clinical symptoms despite nonsurgical management in the absence of substantial risk factors for failure. [2] (10.5435/00124635-201111000-00002)
• [L5] Current consensus suggests rotator cuff injuries are most accurately diagnosed with a combination of cuff- and impingement-specific clinical tests. [3] (10.1016/j.arthro.2013.07.265)
• [Case_report] Deltoid complications combined with rotator cuff pathology represent a rare but devastating complication with no well-described surgical option. [4] (10.1016/j.jse.2011.09.023)
• [L3] Increasing knowledge about this syndrome, including better imaging, has facilitated patient treatment for a stable spectrum of rotator cuff pathology, as has the application of endoscopic surgery. [5] (10.1016/j.arthro.2010.02.029)
• [L5] Understanding the function and pathology surrounding the teres minor is paramount in comprehensive management of the patient with shoulder pathology. [6] (10.5435/jaaos-d-15-00258)
• [L4] In the context of rotator cuff disease, the etiology of anterior shoulder pain with macroscopic changes in the biceps tendon is related to the complex interaction of the tendon and surrounding soft tissues, rather than a single entity. [8] (10.1016/j.jse.2008.05.044)
• [L4] The KSS is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders. [9] (10.1016/j.jse.2008.11.019)
• [L2] In one-quarter of patients with painful cuff tears, pain developed in a contralateral asymptomatic cuff tear that resulted in a measurable decline in function within 3 years. [10] (10.1016/j.jse.2023.09.008)
• [L4] Outcomes after repair of partial- and full-thickness rotator cuff tears using a bioinductive implant show safety and efficacy at 1-year follow-up. [11] (10.1016/j.arthro.2019.02.019)
• [L1] At a 2-year follow-up, shoulder function evaluated in terms of CMS was not significantly improved. [12] (10.1186/s12891-020-03872-4)
• [L5] Severely impaired deltoid function, an isolated supraspinatus tear, and the presence of full active shoulder elevation with a massive rotator cuff tear and arthritis are contraindications to RTSA. [13] (10.1007/s11999-009-1188-9)
• [L3] The acromial morphology classification system is an unreliable method to assess the acromion, and the acromial index shows no association with the presence of rotator cuff disease. [14] (10.1016/j.jse.2011.09.028)
• [L3] Ultrasound is an useful tool for discovering in pre-symptomatic stages the subjects that may undergo shoulder symptomatic pathologies. [15] (10.1186/1471-2474-11-278)
• [L1] The natural history of rotator cuff tendinopathy probably plays a significant role in the results in the long-term. [16] (10.1302/0301-620x.99b6.bjj-2016-0569.r1)
• [L5] However, treatment of these patients is challenging, and results are comparatively inferior to those of treating patients with smaller rotator cuff tears. [17] (10.5435/00124635-200309000-00005)
• [L3] Early operative treatment appears to be better for rotator cuff tears with a sudden onset of symptoms and poor function to achieve maximal return of shoulder function. [18] (10.1016/j.jse.2005.07.006)
• [L5] The editorial states that shoulder arthroscopy literature remains controversial, conclusions are often unsupported due to bias and limitations, and no clinical guidelines are definitive pending higher levels of evidence. [19] (10.1016/j.arthro.2012.07.001)
• [L4] Increased age and longer duration of follow-up were associated with lower healing rates after double-row rotator cuff repair. [20] (10.1177/0363546510382835)
• [L1] PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair. [21] (10.1016/j.arthro.2012.03.007)
• [L4] 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. [22] (10.1016/j.jse.2011.11.033)
• [Case_report] This case highlights the importance of the initial workup after high-velocity trauma and that open approaches for rotator cuff repairs continue to have indications in certain circumstances. [23] (10.1016/j.jse.2009.07.014)
• [L4] The use of MRI before a trial of conservative management in patients with atraumatic shoulder pain, minimal to no strength deficits on physical examination, and suspected cuff tendinopathy other than full-thickness tears provides negative value in the management of these patients, at both the individual and population level. [24] (10.1016/j.jse.2019.04.003)
• [L1] On the basis of the currently available literature, there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up. [26] (10.1016/j.arthro.2011.11.022)
• [L4] Arthroscopic rotator cuff repair leads to a structural failure rate of 33% but satisfactory functional results with high patient satisfaction at midterm follow-up. [27] (10.1016/j.jse.2015.05.051)
• [L5] This article provides a systematic approach to the interpretation of a magnetic resonance examination of the shoulder, describing the normal imaging appearance of each anatomical structure, the most useful pulse sequences and imaging planes, and the signs of injury. [28] (10.1177/0363546505278255)
• [L4] Imaging is an essential tool for evaluation of patients with shoulder pain; understanding the extent of an injury with imaging is key to successful management. [29] (10.1016/j.csm.2013.03.009)
• [L3] This study was the first to create a classification system to divide coracoids according to their morphology and relative risk of associated subscapularis tears. [30] (10.1016/j.jse.2020.01.074)
• [L5] Tears of the subscapularis have greater biomechanical consequences than do tears of the infraspinatus. [31] (10.1016/j.arthro.2009.09.007)
• [L4] Rotator cuff injuries in adolescents may be overlooked as a cause of disability, leading to significant delays in diagnosis. [32] (10.1177/0363546504269033)
• [L1] This systematic review of the available literature indicates that there is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease. [33] (10.5435/00124635-200701000-00002)
• [L4] Intratendinous rotator cuff tears are difficult to diagnose preoperatively. [34] (10.1016/j.jse.2010.01.013)
• [L4] Current physiotherapy practice in relation to rotator cuff disorders is variable, which might reflect the lack of high-quality evidence available. [35] (10.1177/1758573217717103)
• [L4] Current physiotherapy practice in relation to rotator cuff disorders is variable, which might reflect the lack of high-quality evidence available. [36] (10.1111/j.1758-5740.2011.00164.x)
• [L3] This study confirms dynamic superior migration of the humeral head during abduction in patients with rotator cuff tears using in vivo 3D kinematic analysis. [37] (10.1016/j.arthro.2015.08.031)
• [L2] The FSS is a patient-reported outcome measure that can easily be incorporated into clinical practice, providing a quick, reliable, valid and practical measure for rotator cuff problems. [38] (10.1177/1758573215578589)
• [L5] Following nonoperative treatment for at least 6 weeks, SAD is a viable and good surgical option for the treatment of shoulder impingement with an intact rotator cuff. [39] (10.1016/j.arthro.2019.06.012)
• [L5] In massive rotator cuff tear, the pectoralis major and latissimus dorsi muscles are effective in improving glenohumeral kinematics and reducing acromiohumeral pressures. [40] (10.1016/j.jse.2013.11.030)
• [L4] ASD without cuff repair appears to be a safe, efficacious, and sustainable procedure for patients with partial rotator cuff tears. [41] (10.1016/j.arthro.2015.08.026)
• [L5] Nonoperative treatment is appropriate as initial therapy, while operative management including arthroscopic subacromial decompression, debridement, or repair is considered when nonoperative treatment fails. [42] (10.5435/00124635-199901000-00004)
• [L3] Most abnormal MRI findings were not different in frequency between symptomatic and asymptomatic shoulders. [43] (10.1016/j.jse.2019.04.001)
• [L2] However, improvement in symptoms and functional outcomes was significantly worse in patients who had a partial-thickness rotator cuff tear compared with patients who had an isolated tendinopathy. [44] (10.1016/j.arthro.2023.03.019)
• [L2] Orthobiologics offer a relatively safe management option with inconclusive evidence for or against its use for rotator cuff pathology. [45] (10.3233/bmr-201844)
• [L5] Biomechanical studies indicate that the long head of the biceps contributes to stability of the glenohumeral joint in all directions, though in vivo studies have yet to establish this stabilizing effect and the physiologic load required remains unknown. [46] (10.1016/j.arthro.2010.10.014)
• [L3] CSA and AI do not appear to influence 24-month functional outcomes postoperatively and hence are not contraindications to arthroscopic rotator cuff repair. [47] (10.1177/0363546517717947)
• [L5] Arthroscopy is a safe and effective treatment for symptomatic calcific tendonitis of the shoulder, excluding or including patients with rotator cuff tears, but patients with intact cuffs could benefit from needling or ESWT in some cases. [48] (10.1016/j.arthro.2015.11.003)
• [L1] Routine arthroscopic SSNR is not recommended when treating patients with rotator cuff tear. [49] (10.1007/s00167-022-07066-4)
• [L2] Comparing histopathological data with demographical information allows for the identification of rotator cuff tears at risk of repair failure. [50] (10.1007/s00167-011-1521-1)
• [L5] Increasing supraspinatus tendon loading causes a mechanical interaction between the two tendons, paralleling the increase in supraspinatus tendon strain. [51] (10.1016/j.jse.2009.10.003)
• [L3] The physiopathology is related to dysfunction of the anterosuperior glenohumeral capsular ligament rather than the inferior glenohumeral ligament. [52] (10.1016/j.jse.2022.10.005)
• [L5] Additional repair of the partial subscapularis tear with supraspinatus tear did not affect external rotation or glenohumeral kinematics. [53] (10.1016/j.jse.2013.09.015)
• [L2] These data can be used to select optimal candidates for operative treatment of rotator cuff tears and assist with patient education and expectations before treatment. [54] (10.1016/j.jse.2018.04.016)
• [L4] Although functional status improved with time after 6 months, the structural status of repaired cuffs remained unchanged between 6 and 19 months. [55] (10.1016/j.jse.2011.05.027)
• [L2] The currently limited available evidence on PRP for nonoperative treatment of chronic rotator cuff disease suggests that in the short term, PRP injections may not be beneficial. [56] (10.1016/j.arthro.2018.10.115)
• [L5] Shoulders with rotator cuff tears require considerable compensatory deltoid function to prevent abduction motion loss. [57] (10.1177/0363546518768276)
• [L3] MRI and US provide similar assessments of postoperative rotator cuff healing, although US is less sensitive. [58] (10.1016/j.otsr.2015.06.006)
• [L3] Pain reduction caused shifts in scapulohumeral rhythm resulting in an increase in glenohumeral motion and a reduced reliance on scapular rotation. [59] (10.1016/j.jse.2007.05.010)
• [L4] This study shows that improvement in functional outcome after arthroscopic repair of a subscapularis tendon tear is maintained long-term. [60] (10.1016/j.arthro.2012.02.031)
• [L5] The clinical evidence to support correction of the critical shoulder angle with lateral acromioplasty is insufficient at this time, and further research is required to demonstrate an association between critical shoulder angle and clinical outcomes before treatment algorithms should be altered. [61] (10.1016/j.arthro.2018.06.020)
• [L3] The critical shoulder angle, posterior acromial height, and posterior acromial tilt do not change significantly over a long-term follow-up of at least 10 years, supporting the hypothesis that these scapular morphologic parameters are stable anthropometric characteristics. [62] (10.1016/j.jse.2020.09.042)
• [L5] Simulated isolated supraspinatus cord and strap tears significantly reduced shoulder abduction force, with cord tears causing a larger decline than strap tears. [63] (10.1016/j.jse.2023.07.003)
• [Commentary] Shoulder MRI may be warranted for preoperative planning in the select population of patients with chronic calcific tendinopathy and prolonged refractory pain, although the probability of identifying additional cuff pathology requiring surgical intervention is very low. [64] (10.1016/j.arthro.2020.01.014)
• [L3] Preoperative MRI scans of the shoulder interpreted by orthopaedic surgeons with the described systematic approach resulted in improved accuracy in diagnosing subscapularis tendon tears compared with previous studies. [65] (10.1016/j.arthro.2012.04.142)
• [L5] The critical shoulder angle may not be responsible for rotator cuff tears; rather, patient activities throughout several decades could induce both cuff lesions and bone remodeling at the acromial level. [66] (10.1016/j.arthro.2020.04.030)
• [L4] Gene expression in human rotator cuff muscles varied according to tendon injury severity. [67] (10.2106/jbjs.m.01585)
• [L1] The diagnostic accuracy of US, MRI and MRA in the characterisation of full-thickness rotator cuff tears is high with overall estimates of sensitivity and specificity over 0.90. [68] (10.1136/bjsports-2014-094148)
• [L1] Arthroscopic acromioplasty significantly improves long-term clinical outcomes up to 2 years. [69] (10.1177/0363546515608485)
• [L4] A non-contrast shoulder MRI obtained in the community setting after non-dislocating shoulder trauma has a moderate sensitivity for most intraarticular pathologies when interpreted by musculoskeletal radiologists. [70] (10.1007/s00167-014-3102-6)
• [L2] There were no differences of clinically relevant size between arthroscopic and open rotator cuff surgery in this comparative series. [71] (10.1007/s11999-014-3715-6)
• [L3] The MRI tendinosis grade is associated with stiffness assessed using sonoelastography in patients with rotator cuff tendinopathy. [72] (10.1016/j.jse.2015.10.019)
• [L5] The study identified two distinctive characteristics of the human scapula: a lateral orientation of the glenoid cavity and a narrow coraco-acromial arch. [73] (10.1016/j.otsr.2014.09.011)
• [L3] Tendinosis severity assessed by preoperative MRI was the only factor associated with failure to heal in patients with partial-thickness and small full-thickness rotator cuff tears. [75] (10.1177/0363546514561004)
• [L3] In this prospective cohort study, patients undergoing operative treatment had significantly better pain and functional outcomes as compared with patients undergoing nonoperative treatment for rotator cuff tears. [76] (10.1177/0363546519873840)
• [L4] This rotator cuff MRI protocol can be applied to evaluate morphological tendon outcomes after different treatment modalities. [77] (10.1186/s13018-014-0128-x)
• [L3] Clinicians should assess shoulder strength in the position the patient requires to use their shoulder because cervical spine position may cause weakness that would be missed in standard testing positions. [78] (10.1097/corr.0000000000002212)
• [L3] Shoulders with a symptomatic rotator cuff tear showed higher radioisotope uptake on bone scintigraphy than those with an asymptomatic tear. [79] (10.1177/0363546513494741)
• [L4] Unenhanced magnetic resonance imaging of the shoulder in asymptomatic high performance throwing athletes reveals abnormalities that may encompass a spectrum of nonclinical findings. [80] (10.1177/03635465020300012501)
• [L2] Patients with rotator cuff disease who are treated without surgery and have a 2-point change in the SST score or a 12 to 17-point change in the ASES score experience a clinically important change in self-assessed outcome. [83] (10.2106/jbjs.h.01296)
• [L2] Younger age, lower BMI, more functional capacity, a shorter symptomatic period, reversible changes on MRI, and higher Constant and ASES scores at the first evaluation were good prognostic factors for the natural course of subacromial impingement syndrome. [84] (10.1016/j.jse.2015.06.007)
• [L3] The 'critical period' for healing following rotator cuff repair, during which risks of retears are high, extends to the first 6 months. [85] (10.1007/s00167-016-4276-x)

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