Impingement Subacromial e Bursite

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview¶

• Management of subacromial impingement syndrome includes physical therapy, injections, and surgery for some patients [2].
• There remains a need for high-quality studies of the pathology, etiology, and management of subacromial impingement syndrome [2].
• Current randomized, controlled trial evidence shows no difference in outcomes of shoulder function or pain between surgical and conservative treatment for subacromial impingement syndrome [3].
• Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function [4].
• Subacromial pain syndrome (SAPS) should preferably be treated non-operatively [6].
• Subacromial injection with corticosteroids is indicated for persistent or recurrent symptoms of SAPS [6].
• Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months in patients with shoulder impingement syndrome [10].
• Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy at 5 years for patients with shoulder impingement syndrome [11].
• Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome [16].
• Arthroscopic subacromial decompression yields good long-term results in the treatment of subacromial impingement for small full-thickness tears [13].
• Adding a large dose of shoulder strengthening to current nonoperative care for patients with subacromial impingement did not result in superior shoulder-specific patient-reported outcomes [14].
• For patients with a long-term disease course, operative treatments may be considered [15].
• Standard arthroscopic subacromial decompression (ASD) surgery is preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression [15].
• Preserving the subacromial bursa during rotator cuff surgery may lead to better rotator cuff healing when secondary pain is manageable [22].
• Arthroscopic subacromial decompression is a valid treatment, reducing pain and improving quality of life for patients selected for surgery according to the Danish national guidelines [26].

Anatomy & Pathophysiology¶

• Ultrasound guidance is not superior to landmark-based techniques for subacromial bursa injections regarding pain or function outcomes [4].
• Ultrasound guidance is not superior to landmark-based techniques for glenohumeral joint injections regarding pain or function outcomes [4].
• Ultrasound guidance is superior to landmark-based techniques for bicipital groove injections [4].
• A comprehensive classification of individualized impingements around the anterior aspect of the shoulder has been proposed to address conflicting etiologic theories and improve understanding of diagnosis and treatment [5].
• Imaging abnormalities of the acromioclavicular joint are common in asymptomatic shoulders [7].
• Imaging abnormalities of the subacromial space are common in asymptomatic shoulders [7].
• There is no relationship between acromiohumeral distance (AHD) and pain in adults with subacromial pain syndrome [18].
• There is no between-group difference in AHD in neutral shoulder position between symptomatic and asymptomatic groups [18].
• There is no between-group difference in AHD at 45° shoulder abduction between symptomatic and asymptomatic groups [18].
• There is no between-group difference in AHD at 60° shoulder abduction between symptomatic and asymptomatic groups [18].
• Subacromial notching rates are low following reverse shoulder arthroplasty using a 135° inlay humeral component and a lateralized glenoid [19].
• Subacromial notching is not associated with functional outcomes at short-term follow-up [19].
• Subacromial notching is not associated with range of motion at short-term follow-up [19].
• Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0° shoulder abduction [31].
• Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 30° shoulder abduction [31].
• Subacromial balloon spacer (SBS) implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 60° shoulder abduction [31].
• Subacromial balloon spacers resist superior humeral head migration in cadaveric studies [45].
• Subacromial balloon spacers reduce subacromial pressure in cadaveric studies [45].
• Conservation of sufficient subacromial space may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
• Conservation of sufficient coracohumeral space may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
• Conservation of scapular posture may have a significant impact on the passive and active function of reverse shoulder arthroplasty [33].
• Understanding moment arms is essential to optimize active force generation in reverse shoulder arthroplasty [33].
• Understanding muscle tensioning is essential to optimize reverse shoulder arthroplasty performance [33].
• Superior capsular reconstruction (SCR) improves glenohumeral superior translation compared with rotator cuff tear at time zero [37].
• Superior capsular reconstruction (SCR) improves subacromial contact pressure compared with rotator cuff tear at time zero [37].
• The improvement in glenohumeral superior translation and subacromial contact pressure with SCR is independent of graft type [37].
• Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be an appropriate treatment direction for subacromial pain syndrome [34].
• Scapular-focused interventions result in a between-group difference in shoulder abduction range of motion in the short term only [39].
• Patients who are candidates for subacromial decompression have more pronounced range of motion deficits compared to non-candidates [40].
• Patients who are candidates for subacromial decompression do not differ in self-reported shoulder function compared to non-candidates [40].
• Patients who are candidates for subacromial decompression do not differ in strength compared to non-candidates [40].
• Patients who are candidates for subacromial decompression do not differ in pain compared to non-candidates [40].
• A decrease in abduction range of motion is associated with being considered a candidate for subacromial decompression [40].
• A decrease in internal rotation range of motion is associated with being considered a candidate for subacromial decompression [40].
• Increased pain during maximal abduction strength effort is associated with being considered a candidate for subacromial decompression [40].
• The Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire may not be adequate to assess individuals with subacromial pain syndrome when pain occurs above 120 degrees of arm elevation [42].
• Lifestyle factors including sleep behaviors and shoulder usage patterns are potential associations with subacromial impingement syndrome [48].
• Improving sleep behaviors and optimizing shoulder usage patterns are effective measures to prevent subacromial impingement syndrome [48].

Classification¶

• Patients presenting with signs and symptoms of subacromial pain syndrome have a high prevalence of conflicting and concomitant diagnoses [1].
• The article proposes a comprehensive classification of all individualized impingements occurring around the anterior aspect of the shoulder, including newly described entities [5].

Clinical Presentation¶

• Imaging abnormalities of the acromioclavicular joint and subacromial space are common in asymptomatic shoulders [7].
• Synovitis in the subacromial space was milder and not associated with any clinical parameters [8].
• Women aged between 30 and 60 years with subacromial pain syndrome and a calcific deposit of >1.5 cm in length have the highest chance of suffering from symptomatic calcific tendinopathy of the rotator cuff [20].
• Night pain is a common complaint of patients presenting with impingement of the shoulder but cannot be used in isolation as a diagnostic predictor for the presence of a rotator cuff tear [32].
• Examination of the cervical spine in patients with subacromial shoulder pain is variable in randomized controlled trials [24].

Investigations¶

• Due to low certainty of evidence and significant variation among study populations, further research is needed to clarify prevalence estimates of shoulder abnormalities [7].
• Ultrasound guidance is not superior to non-guided injection for pain or function outcomes in the subacromial bursa and glenohumeral joint [4].
• Ultrasound guidance is superior to non-guided injection in the bicipital groove [4].
• Synovitis in the subacromial space was found to be mild and not associated with any clinical parameters in patients with rotator cuff tears [8].
• Diagnostic and therapeutic practices regarding internal impingement of the shoulder differ between surgeons, with French surgeons relying more on CT-arthrography and intra-articular injections while international surgeons favor MRI and physical therapy [41].
• The acromiohumeral distance is significantly smaller on MRI compared to AP radiographs in shoulders with an intact rotator cuff [47].
• The acromiohumeral distance on MRI should not be used as a decision criterion to assess glenohumeral centering or subacromial space width in shoulders with an intact rotator cuff [47].
• Machine learning-based ultrasomics may be helpful in the preliminary screening of shoulder pain for subacromial impingement syndrome stages [49].
• The subacromial space width is smaller in nearly all rotator cuff pathologies, becomes even smaller as condition severity increases, and is smaller in the case of a complete cuff tear [50].

Treatment¶

• Ultrasound guidance is not superior to non-guided techniques in the subacromial bursa and glenohumeral joint injections regarding pain or function [4].
• Subacromial pain syndrome should preferably be treated non-operatively, with subacromial injection with corticosteroids indicated for persistent or recurrent symptoms [6].
• Most management regimes for subacromial impingement employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections [9].
• Arthroscopic subacromial decompression yields good long-term results in patients with small full-thickness tears [13].
• Adding a large dose of shoulder strengthening to current nonoperative care for subacromial impingement did not result in superior shoulder-specific patient-reported outcomes [14].
• For patients with a long-term disease course, operative treatments may be considered, with standard arthroscopic subacromial decompression (ASD) surgery preferred over arthroscopic bursectomy and open surgical technique [15].
• Arthroscopic subacromial decompression is a valid treatment that reduces pain and improves quality of life for patients selected for surgery according to Danish national guidelines [26].
• Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair [27].
• There is no evidence from available randomized controlled trials for differences in outcome in pain and shoulder function between conservatively and surgically treated patients with subacromial impingement syndrome [28].
• The evidence on the effectiveness of surgical or conservative treatment of shoulder impingement is limited based on a review of seven randomized controlled trials [35].
• There is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease [38].

Complications¶

• Subacromial osteolysis has a relatively high and variable incidence following hook plate fixation for acromioclavicular dislocation [17].
• The primary factor influencing the reported incidence of subacromial osteolysis is the radiological assessment method [17].
• Rates of subacromial notching are low following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid [19].
• When subacromial notching occurs, it is not associated with functional outcomes or range of motion at short-term follow-up [19].

Recovery¶

• Variation exists in the management regimes offered to patients with subacromial impingement, but most employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections [9].
• Arthroscopic subacromial decompression (ASD) in the treatment of subacromial impingement yields good long-term results [13].
• For patients who have a long-term disease course, operative treatments may be considered, with standard ASD surgery preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression [15].
• Subacromial osteolysis has a relatively high and variable incidence, and the primary factor influencing the reported incidence is the radiological assessment method [17].
• There was no between group difference in acromiohumeral distance (AHD) in neutral shoulder position, shoulder abduction at 45° or 60° [18].
• When subacromial notching occurs following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid, it is not associated with functional outcomes or range of motion at short-term follow-up [19].
• More than half of patients diagnosed with subacromial pain syndrome in specialist care settings do not adhere to recommendations regarding duration of exercise-therapy, but this is not related to symptom improvement [23].
• Major improvements in pain/function were seen at mid- to long-term after isolated arthroscopic subacromial decompression and combined decompression/rotator cuff repair [25].
• Adding a large dose of shoulder strengthening exercises to nonoperative care for 16 weeks did not significantly improve long-term outcomes in terms of shoulder disability, health-related quality of life, sick leave, or surgery rates at 1 year [29].
• There was no evidence of progression of intrinsic rotator cuff pathologic conditions at a mean follow-up of 4.5 years for partial-thickness rotator cuff tears treated with acromioplasty without repair [30].

Key Evidence¶

• [L3] Patients presenting with signs and symptoms of subacromial pain syndrome have a high prevalence of conflicting and concomitant diagnoses. [1] (10.1177/23259671251332942)
• [L5] Management of subacromial impingement syndrome includes physical therapy, injections, and surgery for some patients, but there remains a need for high-quality studies of the pathology, etiology, and management of the condition. [2] (10.5435/00124635-201111000-00006)
• [L1] Current randomized, controlled trial evidence shows no difference in outcomes of shoulder function or pain between surgical and conservative treatment for subacromial impingement syndrome. [3] (10.2106/jbjs.9202.ebo579)
• [L1] Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function. [4] (10.1016/j.arthro.2021.12.013)
• [L4] The article proposes a comprehensive classification of all individualized impingements occurring around the anterior aspect of the shoulder, including newly described entities, to address conflicting theories and improve understanding of their etiologic factors, diagnosis, and treatment. [5] (10.1007/s00264-017-3515-1)
• [Paper] SAPS should preferably be treated non-operatively, with subacromial injection with corticosteroids indicated for persistent or recurrent symptoms. [6] (10.3109/17453674.2014.920991)
• [L2] Due to the low certainty of evidence and significant variation among study populations, further research is needed to clarify these prevalence estimates and to guide evidence-based management of shoulder abnormalities. [7] (10.1186/s13018-024-05378-4)
• [L4] Synovitis in the subacromial space was milder and not associated with any clinical parameters. [8] (10.1177/23259671231207818)
• [L4] Variation exists in the management regimes offered to patients with subacromial impingement, but most employ a minimum period of 12 weeks of conservative management incorporating physiotherapy and at least 2 subacromial steroid injections. [9] (10.1177/1758573215571010)
• [L1] In this controlled trial involving patients with a shoulder impingement syndrome, arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months. [10] (10.1136/bmj.k2860)
• [L1] Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy at 5 years for patients with shoulder impingement syndrome. [11] (10.1136/bjsports-2020-102216)
• [L3] ASD in the treatment of subacromial impingement yields good long-term results. [13] (10.1016/j.jse.2007.06.020)
• [L1] Adding a large dose of shoulder strengthening to current nonoperative care for patients with subacromial impingement did not result in superior shoulder-specific patient-reported outcomes. [14] (10.1177/03635465211016008)
• [L1] For patients who have a long-term disease course, operative treatments may be considered, with standard ASD surgery preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression. [15] (10.1097/md.0000000000000510)
• [L1] Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome. [16] (10.1186/s12891-021-04768-7)
• [L1] Subacromial osteolysis has a relatively high and variable incidence, and the primary factor influencing the reported incidence is the radiological assessment method. [17] (10.1016/j.jse.2024.03.018)
• [L1] There was no between group difference in acromiohumeral distance (AHD) in neutral shoulder position, shoulder abduction at 45° or 60°. [18] (10.1038/s41598-020-76704-z)
• [L3] When subacromial notching occurs, it is not associated with functional outcomes or range of motion at short-term follow-up. [19] (10.1016/j.jseint.2024.01.009)
• [L3] This study demonstrates that women aged between 30 and 60 years with subacromial pain syndrome and a calcific deposit of >1.5 cm in length have the highest chance of suffering from symptomatic calcific tendinopathy of the rotator cuff. [20] (10.1016/j.jse.2015.02.024)
• [L5] Preserving the subacromial bursa during rotator cuff surgery may lead to better rotator cuff healing when secondary pain is manageable. [22] (10.1530/eor-2024-0183)
• [L3] More than half of patients diagnosed with subacromial pain syndrome in specialist care settings do not adhere to recommendations regarding duration of exercise-therapy, but this is not related to symptom improvement. [23] (10.1016/j.msksp.2021.102322)
• [L1] Examination of the cervical spine in patients with subacromial shoulder pain is variable in randomized controlled trials. [24] (10.1177/1758573218798023)
• [L3] Major improvements in pain/function were seen at mid- to long-term after isolated arthroscopic subacromial decompression and combined decompression/rotator cuff repair. [25] (10.1016/j.jor.2018.03.004)
• [L4] Arthroscopic subacromial decompression is a valid treatment, reducing pain and improving quality of life for patients selected for surgery according to the Danish national guidelines. [26] (10.1016/j.jse.2017.03.028)
• [L1] Five randomized trials found that formal subacromial decompression does not result in improved clinical outcomes up to 2 years after rotator cuff repair. [27] (10.1016/j.arthro.2012.06.003)
• [L1] According to the best-evidence synthesis, there is no evidence from the available RCTs for differences in outcome in pain and shoulder function between conservatively and surgically treated patients with SIS. [28] (10.1016/j.jse.2009.01.010)
• [L1] Adding a large dose of shoulder strengthening exercises to nonoperative care for 16 weeks did not significantly improve long-term outcomes in terms of shoulder disability, health-related quality of life, sick leave, or surgery rates at 1 year. [29] (10.1177/23259671251374314)
• [L4] There was no evidence of progression of intrinsic rotator cuff pathologic conditions at a mean follow-up of 4.5 years. [30] (10.1177/03635465020300021801)
• [L4] SBS implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0, 30, and 60 of shoulder abduction. [31] (10.1177/03635465221150652)
• [L3] Night pain is a common complaint of patients presenting with impingement of the shoulder but cannot be used in isolation as a diagnostic predictor for the presence of a rotator cuff tear. [32] (10.1111/j.1758-5740.2011.00133.x)
• [L5] Conservation of sufficient subacromial and coracohumeral space and scapular posture may have a significant impact on the passive and active function of reverse shoulder arthroplasty, while understanding moment arms and muscle tensioning is essential to optimize active force generation and RSA performance. [33] (10.3390/jcm12041616)
• [L1] Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be a more appropriate treatment direction for the future. [34] (10.1177/1758573216660038)
• [L1] Based on the review of seven RCTs, the evidence on effectiveness of surgical or conservative treatment of shoulder impingement was found to be limited. [35] (10.3109/09638288.2014.907364)
• [L1] Independent of graft type, biomechanical studies suggest that SCR improves glenohumeral superior translation and subacromial contact pressure in comparison with RTC tear at time zero. [37] (10.1016/j.arthro.2023.08.025)
• [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. [38] (10.5435/00124635-200701000-00002)
• [L1] A between-group difference in shoulder abduction ROM in the short term only was found. [39] (10.1080/09593985.2018.1423656)
• [L4] A decrease in abduction and internal rotation range of motion, and increased pain during maximal abduction strength effort are associated with being considered a candidate for subacromial decompression, while self-reported shoulder function, pain during the last week, and rotator cuff strength are not. [40] (10.1007/s00167-018-4894-6)
• [L4] Diagnostic and therapeutic practices regarding internal impingement of the shoulder differ between surgeons in France and in other countries, with French surgeons relying more on CT-arthrography and intra-articular injections, while international surgeons favor MRI and physical therapy. [41] (10.1016/j.otsr.2019.09.007)
• [L4] The DASH may not be adequate to assess those with shoulder pain above 120 degrees of arm elevation. [42] (10.1093/ptj/pzab065)
• [L1] In cadaveric studies, subacromial balloon spacers resist superior humeral head migration and reduce subacromial pressure. [45] (10.1016/j.asmr.2020.06.011)
• [L4] The acromiohumeral distance is significantly smaller in the MRI in comparison to AP radiographs in shoulders with an intact rotator cuff and should not be used as a decision criterion on MRI to assess glenohumeral centering or subacromial space width. [47] (10.1007/s00167-020-06090-6)
• [L1] This evidence supports the development of strategies aimed at improving sleep behaviors and optimizing shoulder usage patterns as effective measures to prevent SIS. [48] (10.1186/s12891-024-07345-w)
• [L4] This noninvasive and low-cost approach may be helpful in the preliminary screening of shoulder pain. [49] (10.1002/jum.15914)
• [L4] The subacromial space width is smaller in nearly all rotator cuff pathologies, but becomes even smaller as the severity of the condition increases and is smaller in the case of a complete cuff tear. [50] (10.1016/j.ultras.2003.11.015)

References¶

[1] The Challenge of Diagnosing Patients Presenting With Signs and Symptoms of Subacromial Pain Syndrome: A Descriptive Study of 741 Patients Seen in a Secondary Care Setting. Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/23259671251332942

[2] Subacromial Impingement Syndrome. American Academy of Orthopaedic Surgeon. 2011. DOI: 10.5435/00124635-201111000-00006

[3] Current Evidence Fails to Show Differences in Effectiveness Between Conservative and Surgical Treatment of Subacromial Impingement Syndrome. The Journal of Bone & Joint Surgery. 2010. DOI: 10.2106/jbjs.9202.ebo579

[4] Ultrasound Guidance Is Not Superior in Subacromial Bursa and Intraarticular Injections but Superior in Bicipital Groove: A Meta-analysis of Randomized Controlled Trials. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2022. DOI: 10.1016/j.arthro.2021.12.013

[5] Redefining anterior shoulder impingement: a literature review. International Orthopaedics. 2017. DOI: 10.1007/s00264-017-3515-1

[6] Guideline for diagnosis and treatment of subacromial pain syndrome. Acta Orthopaedica. 2014. DOI: 10.3109/17453674.2014.920991

[7] Imaging abnormalities of the acromioclavicular joint and subacromial space are common in asymptomatic shoulders: a systematic review. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-024-05378-4

[8] Clinical Implication of Glenohumeral and Subacromial Synovitis in Rotator Cuff Tears. Orthopaedic Journal of Sports Medicine. 2023. DOI: 10.1177/23259671231207818

[9] Current UK practices in the management of subacromial impingement. Shoulder & Elbow. 2015. DOI: 10.1177/1758573215571010

[10] Subacromial decompression versus diagnostic arthroscopy for shoulder impingement: randomised, placebo surgery controlled clinical trial. BMJ. 2018. DOI: 10.1136/bmj.k2860

[11] Subacromial decompression versus diagnostic arthroscopy for shoulder impingement: a 5-year follow-up of a randomised, placebo surgery controlled clinical trial. British Journal of Sports Medicine. 2020. DOI: 10.1136/bjsports-2020-102216

[13] Small full-thickness tears do well ten to thirteen years after arthroscopic subacromial decompression. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2007.06.020

[14] Effectiveness of Adding a Large Dose of Shoulder Strengthening to Current Nonoperative Care for Subacromial Impingement: A Pragmatic, Double-Blind Randomized Controlled Trial (SExSI Trial). The American Journal of Sports Medicine. 2021. DOI: 10.1177/03635465211016008

[15] Treatments for Shoulder Impingement Syndrome. Medicine. 2015. DOI: 10.1097/md.0000000000000510

[16] Return to work after subacromial decompression, diagnostic arthroscopy, or exercise therapy for shoulder impingement: a randomised, placebo-surgery controlled FIMPACT clinical trial with five-year follow-up. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04768-7

[17] Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation: a systematic review and meta-analysis. Journal of Shoulder and Elbow Surgery. 2024. DOI: 10.1016/j.jse.2024.03.018

[18] No relationship between the acromiohumeral distance and pain in adults with subacromial pain syndrome: a systematic review and meta-analysis. Scientific Reports. 2020. DOI: 10.1038/s41598-020-76704-z

[19] Rates of subacromial notching are low following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid. JSES International. 2024. DOI: 10.1016/j.jseint.2024.01.009

[20] Prevalence of calcific deposits within the rotator cuff tendons in adults with and without subacromial pain syndrome: clinical and radiologic analysis of 1219 patients. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2015.02.024

[22] Removal or retention: evolving views on possible roles of the subacromial bursa in rotator cuff disease. EFORT Open Reviews. 2025. DOI: 10.1530/eor-2024-0183

[23] Less than half of patients in secondary care adheres to clinical guidelines for subacromial pain syndrome and have acceptable symptoms after treatment: A Danish nationwide cohort study of 3306 patients. Musculoskeletal Science and Practice. 2021. DOI: 10.1016/j.msksp.2021.102322

[24] Screening of the cervical spine in subacromial shoulder pain: A systematic review. Shoulder & Elbow. 2018. DOI: 10.1177/1758573218798023

[25] Long-term results after surgical treatment of subacromial pain syndrome with or without rotator cuff tear. Journal of Orthopaedics. 2018. DOI: 10.1016/j.jor.2018.03.004

[26] Acromioplasty in patients selected for operation by national guidelines. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.03.028

[27] The Changing Role of Acromioplasty. Arthroscopy. 2012. DOI: 10.1016/j.arthro.2012.06.003

[28] Conservative or surgical treatment for subacromial impingement syndrome? A systematic review. Journal of Shoulder and Elbow Surgery. 2009. DOI: 10.1016/j.jse.2009.01.010

[29] The Effect of Adding a Large Dose of Shoulder Strengthening to Nonoperative Care for Subacromial Impingement on Shoulder Disability, Quality of Life, Sick Days, and Surgery Rates: 1-Year Results From a Pragmatic, Double-Blind Randomized Controlled Trial (SExSI). Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/23259671251374314

[30] The Partial-Thickness Rotator Cuff Tear: Is Acromioplasty without Repair Sufficient?. The American Journal of Sports Medicine. 2002. DOI: 10.1177/03635465020300021801

[31] Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears Is Associated With Restoration of the Acromiohumeral Interval and Glenohumeral Center of Pressure: A Systematic Review and Meta-Analysis of Controlled Laboratory Studies. The American Journal of Sports Medicine. 2023. DOI: 10.1177/03635465221150652

[32] Night Pain is not a useful Diagnostic Indicator of Cuff Tear in Patients with Symptoms of Subacromial Impingement. Shoulder & Elbow. 2011. DOI: 10.1111/j.1758-5740.2011.00133.x

[33] Challenges for Optimization of Reverse Shoulder Arthroplasty Part II: Subacromial Space, Scapular Posture, Moment Arms and Muscle Tensioning. Journal of Clinical Medicine. 2023. DOI: 10.3390/jcm12041616

[34] Electromyographic activity of the shoulder muscles during rehabilitation exercises in subjects with and without subacromial pain syndrome: a systematic review. Shoulder & Elbow. 2016. DOI: 10.1177/1758573216660038

[35] Conservative treatment or surgery for shoulder impingement: systematic review and meta-analysis. Disability and Rehabilitation. 2014. DOI: 10.3109/09638288.2014.907364

[37] Glenohumeral Superior Translation and Subacromial Contract Pressure Are Both Improved With Superior Capsular Reconstruction: A Systematic Review and Meta‐analysis of Biomechanical Investigations. Arthroscopy. 2023. DOI: 10.1016/j.arthro.2023.08.025

[38] The Efficacy of Subacromial Corticosteroid Injection in the Treatment of Rotator Cuff Disease: A Systematic Review. Journal of the American Academy of Orthopaedic Surgeons. 2007. DOI: 10.5435/00124635-200701000-00002

[39] Scapular focused interventions to improve shoulder pain and function in adults with subacromial pain: A systematic review and meta-analysis. Physiotherapy Theory and Practice. 2018. DOI: 10.1080/09593985.2018.1423656

[40] Patients who are candidates for subacromial decompression have more pronounced range of motion deficits, but do not differ in self-reported shoulder function, strength or pain compared to non-candidates. Knee Surgery, Sports Traumatology, Arthroscopy. 2018. DOI: 10.1007/s00167-018-4894-6

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