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肩峰下撞击综合征与滑囊炎

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Subacromial impingement — causes of shoulder pain with overhead activity, diagnosis, and treatment options.

Updated Aug 2026
一幅手绘插图，显示肩袖和滑囊在肩峰下被挤压。
肩峰下撞击综合征：肩袖在肩峰下方受到挤压。 Kieran Hirpara 4.0

本页面由机器翻译，尚未经临床医生审核。英文版本为权威版本。

您的感受

您可能会感到肩部上方有深层的酸痛。这种疼痛通常会沿着手臂外侧向下放射。这是由肩峰下撞击综合征引起的，即关节上方的狭窄空间内组织受到挤压。您可能还伴有滑囊炎，即缓冲该区域的充满液体的囊袋发生肿胀。

当您将手臂举过头顶时，疼痛通常会加重。简单的任务，如从高处的架子上取杯子或将衬衫塞进裤子里，可能会变得困难。您可能难以将手伸到背后扣上胸罩或穿上外套。这些动作会夹挤受刺激的软组织，导致尖锐的不适或钝痛。

您的症状常在夜间发作。许多患者发现很难在患侧侧卧睡眠。躺在肩部上的压力会加剧疼痛，使人难以保持睡眠。您还可能在早晨刚醒来时感到僵硬。

这种情况通常是逐渐发展的。在考虑手术之前，您可能已经疼痛至少六个月。如果休息和抗炎治疗没有效果，尽管您付出了努力，疼痛仍可能持续存在。您可能会感到沮丧，因为日常活动变得具有挑战性。

我们理解这如何影响您的日常生活。我们的目标是减轻这种压力并恢复您的舒适感。通过解决您肩部的机械性挤压，我们旨在帮助您再次无痛地自由活动。

实际发生了什么

您的肩关节在肱骨头顶部与其上方的骨性穹顶之间存在一个狭小的间隙。在这个空间内，当您抬起手臂时，肌腱和充满液体的滑囊会平滑地滑动。这被称为肩峰下间隙。当该区域变窄或发生炎症时，肌腱会受到挤压。这就是肩峰下撞击综合征。摩擦会导致滑囊（即缓冲囊）出现疼痛和肿胀。

您的骨性穹顶的形状起着重要作用。有些人天生具有弯曲或钩状的骨形态，这会自然缩小该间隙。这会在您每次移动手臂时增加对肌腱的压力。喙肩韧带（位于顶部的一条组织带）也可能收紧并向下压迫肌腱。这种机械性挤压正是导致您在抬手过头或侧卧时感到尖锐疼痛的原因。

如果肌腱已经受到刺激或受损，我们常观察到这个问题会加重。慢性炎症会使组织变得僵硬且缺乏弹性。这会限制您的活动范围，尤其是在将手臂向侧面抬起或向内旋转时。您可能会感到无力，或在用力活动时经历疼痛。然而，并非所有出现这些变化的人都需要手术。许多患者首先通过非手术治疗获得缓解。

如果需要手术，目标是为该狭窄空间创造更多空间。这可能涉及磨平骨性穹顶或切除部分韧带。该手术称为肩峰下减压术。其目的是停止挤压，使肌腱能够再次愈合并自由移动。对于某些患者，这可提供显著的疼痛缓解并恢复功能。而对于其他患者，潜在的肌腱损伤可能需要不同的治疗方法，例如直接修复撕裂。您的外科医生将帮助您了解哪种方案最适合您的具体解剖结构和症状。

我们能做什么

本页面反映了 Mater Private Hospital Rockhampton 的上肢外科医生 Kieran Hirpara 博士在诊所中处理此问题的方法。我们为您指引一条从自我护理到手术（仅在必要时）的清晰路径。患者通过全科医生或物理治疗师的转诊来到我们的诊所。诊所评估——包括病史、体格检查以及必要的影像学检查——用于确立诊断。对于退行性或长期存在的问题，我们通常首先尝试非手术治疗。如果非手术治疗未能带来足够的改善，我们会考虑手术。对于结构性或急性问题，可能会立即建议手术。

保守治疗是治疗肩峰下撞击综合征的主要初始手段。我们从改变活动方式开始，以避免引起疼痛的动作。物理治疗旨在增强肩部肌肉力量并改善您的活动范围。您应至少给予该方案 6 周的时间以显现效果。如果疼痛持续存在，我们可能会建议在滑囊（肩骨下方的充满液体的囊）内注射皮质类固醇。这可以减少炎症和疼痛。其效果是暂时的，但可以帮助您更有效地参与物理治疗。部分患者也从透明质酸或 PRP（富血小板血浆）注射中获益，尽管这些方法的证据各不相同。我们会密切监测您的进展，以确保您走在正确的治疗轨道上。

手术仅保留用于保守治疗失败的情况。关节镜下肩峰下减压术是一种有效的治疗方法，可根据国家指南选择患者，从而减轻疼痛并提高生活质量。如果您疼痛持续至少 6 个月，霍金斯试验（Hawkins test，一种特定的体格检查体征）持续呈阳性，并且有影像学证据表明存在机械性撞击，我们会考虑此选项。该手术通过去除骨刺或发炎的组织，为您的肌腱创造更多空间。它是晚期病例中开放手术的替代方案。我们还使用肩峰下滑囊阻滞进行有效的术后镇痛，从而减少对强效止痛药的需求。如果您有肩袖撕裂，手术修复通常比单纯减压术产生显著更好的结果。我们将这些选项作为共同决策提出，确保您了解每一步的益处和局限性。

预期情况

对于许多人来说，由撞击综合征和滑囊炎引起的肩部疼痛可通过非手术治疗得到缓解。特定的运动治疗有效，并能减少手术需求。这些结果在10年后仍可维持。如果疼痛持续存在，保守治疗仍是初始的主要手段，手术仅保留用于未改善的病例。

通常在以下情况下考虑手术：疼痛持续至少6个月，检查时显示机械性撞击征象，且对其他措施无反应。当满足这些特定标准时，结果通常较为积极。您可以预期肩部功能和生活质量得到改善。即使您伴有潜在抑郁症或抑郁症状，这一益处依然成立。

如果接受关节镜下肩峰下减压术，您的恢复过程是可预测的。在已发表的系列研究中，超过90%的患者在4周内能够恢复驾驶，6周内恢复工作；然而，我们的标准建议是，在任何肩部手术后六周内不得驾驶，直到复查时获准。如果您的手术涉及去除钙化沉积物，您可能需要更长时间才能无痛地恢复 unrestricted activity（无限制活动）。如果在不进行肩峰成形术的情况下去除慢性钙化，主观肩部功能的恢复平均需要近3个月。

重要的是要知道，并非所有肩部问题都需要或受益于这种手术。目前没有强有力的证据支持仅针对肩袖肌腱病进行肩峰下减压。此外，如果您需要肩袖修复术，正式的肩峰下减压术在修复后2年内并未带来更好的临床结果。在某些情况下，不进行减压而仅行肩袖修复术的结果显著更好。

您的外科医生将根据仔细的病例选择帮助您决定是否适合手术。如果您不需要手术，运动疗法是一条有效的缓解途径。如果您确实进行手术，目标是减轻疼痛并恢复功能。您的预后取决于您的病情与该特定手术适应症的匹配程度。

何时就诊

如果肩痛在休息及其他非手术治疗六个月后仍未改善，请寻求专科医生评估。如果您出现无力、不稳定，或症状干扰睡眠或工作，也应寻求医疗帮助。当有明确的机械性撞击证据时，通常考虑手术治疗。您的外科医生将通过体格检查来确认特定体征（如Hawkins试验阳性），以确定病因。这有助于确保您接受适当的治疗。早期评估可以明确您是否适合进一步保守治疗或接受肩峰下减压术等手术。

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

Evidence & references

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

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[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

[41] Internal impingement of the shoulder: An international survey of 261 orthopaedic surgeons. Orthopaedics & Traumatology: Surgery & Research. 2019. DOI: 10.1016/j.otsr.2019.09.007

[42] Is the Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire Adequate to Assess Individuals With Subacromial Pain Syndrome? Rasch Model and International Classification of Functioning, Disability and Health. Physical Therapy. 2021. DOI: 10.1093/ptj/pzab065

[45] Implantable Subacromial Balloon Spacers in Patients With Massive Irreparable Rotator Cuff Tears: A Systematic Review of Clinical, Biomechanical, and Financial Implications. Arthroscopy, Sports Medicine, and Rehabilitation. 2020. DOI: 10.1016/j.asmr.2020.06.011

[47] The acromiohumeral distance in the MRI should not be used as a decision criterion to assess subacromial space width in shoulders with an intact rotator cuff. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06090-6

[48] Lifestyle factors and subacromial impingement syndrome of the shoulder: potential associations in finnish participants. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07345-w

[49] Machine Learning‐Based Ultrasomics for Predicting Subacromial Impingement Syndrome Stages. Journal of Ultrasound in Medicine. 2021. DOI: 10.1002/jum.15914

[50] Sonographic evaluation of subacromial space. Ultrasonics. 2004. DOI: 10.1016/j.ultras.2003.11.015

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