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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 Jun 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

肩痛是患者因该问题寻求医疗帮助的最常见原因。您可能正经历肩峰下撞击综合征，这是一种肩部结构受到挤压的状况。这通常涉及肩袖肌腱或肩峰下滑囊，后者是一个充满液体的小囊，用于缓冲您的关节。您在移动手臂时可能会感到疼痛，尤其是在举过头顶或伸向背后时。简单的任务，如把衬衫塞进裤子里或扣上胸罩，可能会变得困难且疼痛。

疼痛常在夜间加剧，使您难以侧卧在患侧入睡。您可能会注意到刚醒来时感到僵硬，随着活动略有缓解。活动往往会使不适加重，特别是在举起重物或伸手够高处的架子时。在许多情况下，炎症不仅存在于滑囊中，还蔓延到主要的肩关节。这种广泛的炎症会导致即使是微小的动作也会引起剧烈疼痛。

虽然这种情况很常见，但您的外科医生会确保没有其他问题导致您的症状。例如，他们会检查是否存在不稳定或罕见的原因，如小的良性肿瘤或钙化沉积物。30至60岁之间患有大于1.5厘米钙化沉积物的女性出现显著症状的风险较高。然而，即使肌腱厚度与另一侧肩膀相比看起来正常，影像学检查也可能显示撞击的迹象。

好消息是，特定的锻炼是有效的，并且可以减少对手术的需求。这些结果通常可以持续多年。如果物理治疗等保守治疗在至少6周后没有效果，您的外科医生可能会讨论其他选择。注射可以通过减少炎症来提供短期缓解。您的护理计划将根据您的具体需求量身定制，重点是让您以更少的疼痛恢复日常活动。

实际发生了什么

您的肩关节是一个球窝关节，外面包裹着一层称为关节囊的紧密结构。在这个空间内，当您抬起手臂时，肌腱和一个充满少量液体的小囊（称为滑囊）会顺畅地滑动。在肩峰下撞击综合征中，这些结构会被挤压到上方的骨骼上。这种挤压会导致炎症，并在您抬高手臂时引起疼痛。

您可能会感觉到这种挤压，这与肩关节肌肉的协同工作方式有关。正常情况下，您的肩袖肌群会将肱骨头保持在关节盂的中心位置。如果这些肌肉无力或协调性差，肱骨头就会向上移位。这会减少肌腱活动的空间。结果是产生摩擦，刺激周围组织。这种刺激正是导致您剧烈疼痛和活动受限的原因。

影像学检查有助于您的外科医生准确定位挤压发生的位置。它可以显示滑囊是否有肿胀或肌腱是否增厚。然而，并非所有有疼痛症状的人在影像扫描中都会显示出明显的改变。有些人肌腱外观正常，但由于肩关节运动模式异常，仍然会感到疼痛。这就是为什么您的外科医生会同时评估您的症状和运动模式。

治疗的重点在于纠正这种运动异常。物理治疗有助于增强稳定关节的肌肉。这为肌腱提供了更多的滑动空间，避免其受到挤压。注射治疗也可以通过快速减轻炎症来帮助缓解症状。这为您开始锻炼提供了一个缓解窗口。大多数患者通过这些非手术方法都能得到改善。手术很少需要，仅在其他治疗六周后无效时才会考虑。

我们能采取的措施

从自我管理和物理治疗开始。您的外科医生可能会推荐特定的锻炼以增强肩部周围肌肉。这种方法有效，并能减少手术需求。这种锻炼治疗的益处可长期维持，结果在10年后依然持续。您应给予这种保守治疗充分的机会以发挥作用。如果经过至少6周的保守治疗后未见改善，您的外科医生可能会讨论其他选择。较年轻的年龄、较低的体重指数（BMI）以及在开始治疗前症状持续时间较短，均为恢复良好的迹象。

如果单纯锻炼不足以提供足够的缓解，您的外科医生可能会建议药物治疗。这通常包括止痛药和抗炎药。向肩胛骨下方的空间（肩峰下间隙）注射也可提供帮助。皮质类固醇注射是缓解疼痛和改善功能的短期有效疗法。部分患者也可能从透明质酸注射中受益，其在短期内提供的镇痛效果与类固醇相似。另一种选择是自体条件血浆（ACP），它利用您自身的血液成分，如果您不能使用类固醇，这是一个良好的替代方案。单次注射酮咯酸在4周时可能比标准类固醇注射带来更大的改善。虽然对于该区域，超声引导并不优于盲探注射，但准确的诊断和正确的技术对于取得良好结果至关重要。

仅在保守治疗达到极限时才考虑手术。如果您在尝试非手术治疗后仍存在持续性疼痛和功能丧失，则表明需要手术。您的外科医生将评估关节镜下肩峰下减压术是否对您可行，特别是如果您的肩袖完整。请注意，最近的证据表明，手术可能不会为所有肩峰下撞击综合征患者带来可辨别的益处，甚至可能造成损害。因此，您的外科医生在推荐手术前会仔细权衡风险与益处。MRI等影像学工具有助于确定损伤程度，但在类固醇注射后不久解读扫描结果时需谨慎，因为注射有时可能模拟撕裂的表现。

预期情况

您的肩痛通常源于滑囊的肿胀，滑囊是包裹关节、充满液体的小囊。这种情况称为肩峰下撞击综合征。好消息是，您的身体通常能够自行治愈此症。事实上，94%的自发性冻结肩患者无需任何治疗即可恢复至正常功能与活动水平。即使您没有冻结肩，这种疼痛的自然病程也往往随时间推移而改善。许多人发现特定的运动治疗有效，并减少了对手术的需求。这些益处至少可维持10年。

如果您的疼痛持续存在，您的外科医生可能会建议非手术选项。注射可提供短期缓解。肩关节内注射类固醇可有效减轻疼痛并在短期内改善功能。这些注射无需超声引导；其效果与有超声引导时相当。其他注射，如使用人胎盘水解物或透明质酸的注射，也显示出在减轻疼痛和提高生活质量方面的显著改善。物理治疗是这一过程的关键部分。它帮助您恢复力量与活动度。

手术通常不是首选。证据支持对肩峰下撞击综合征采取非手术治疗或不予治疗。关节镜治疗无明显益处，且可能导致伤害。即使您有钙化沉积物，去除它们无需额外去除骨质即可获得良好的短期结果。如果您确实需要手术，通常仅在非手术治疗至少6周后才考虑。您的外科医生会仔细评估您的进展。

某些因素会影响您的恢复速度。较年轻的年龄、较低的体重指数（BMI）以及在开始治疗前症状持续时间较短都是良好的迹象。MRI上的可逆性变化也预示着更好的预后。然而，请注意，术前肩关节注射与较高的翻修率相关。这种风险取决于您接受的注射次数以及注射的时间。总体而言，大多数患者通过保守治疗得到改善。您的外科医生将帮助您找到休息、运动和药物的适当平衡，以助您恢复日常活动。

何时就诊

肩痛很常见，通常由撞击综合征或滑囊炎引起。如果休息后疼痛仍持续，请咨询您的全科医生。如果出现无力、不稳定，或肩部出现卡住或脱位的情况，请寻求专科医生评估。如果症状干扰睡眠或工作，请联系您的外科医生。疼痛突然加重也需要及时就医。虽然许多病例通过保守治疗可改善，但有些病例涉及罕见的肿瘤或大块骨沉积物，需要手术切除。如果标准治疗无效，您的医生会检查这些特定问题。早期评估有助于将撞击综合征与其他疾病（如关节不稳定）区分开来。正确的诊断可确保您接受适当的治疗，以恢复活动度并减轻炎症。

Reviewed by Dr Kieran Hirpara · 10 June 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

Overview

  • Blind subacromial corticosteroid injections are as effective as ultrasound-guided injections for improving pain and function in subacromial impingement syndrome after short-term follow-up [1].
  • Ultrasound guidance is not superior to blind injection for subacromial bursa injections regarding pain or function outcomes [4].
  • Ultrasound guidance is superior to blind injection for bicipital groove injections [4].
  • Subacromial injections of human placenta hydrolysate show significant improvement in pain, functional level, and quality of life in patients with shoulder impingement syndrome [3].
  • Subacromial injection of corticosteroids is an effective short-term therapy for symptomatic subacromial impingement syndrome [8].
  • Subacromial steroid injection is an alternative modality for primary frozen shoulder, and treatment should be individualized [12].
  • 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].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there are more cases of ultrasonographic impingement in affected shoulders compared to unaffected shoulders [5].
  • There are no significant differences in supraspinatus tendon thickness, subacromial bursa thickness, or acromio-humeral distance between affected and unaffected shoulders in patients with isolated unilateral subacromial pain syndrome [5].
  • Arthroscopic bursectomy and debridement of calcific deposits for calcific tendonitis yields short-term functional outcomes that are not influenced by the addition of subacromial decompression [10].
  • Arthroscopic treatment should no longer be offered to people with subacromial impingement as surgery offers no discernible benefits but may result in harm [15].
  • The weight of evidence supports nonoperative management or no treatment for subacromial impingement [15].
  • Specific exercise treatment for patients with subacromial pain is effective and reduces the need for surgery, with maintained results after 10 years [18].
  • There is no uniform definition for any of the diagnostic labels for shoulder pain across different randomized controlled trials [19].
  • Following nonoperative treatment for at least 6 weeks, subacromial decompression is a viable and good surgical option for shoulder impingement with an intact rotator cuff [24].

Anatomy & Pathophysiology

  • Ultrasound guidance is not superior to non-guided injection for the subacromial bursa in terms of pain or function outcomes [4].
  • Ultrasound guidance is not superior to non-guided injection for the glenohumeral joint in terms of pain or function outcomes [4].
  • Ultrasound guidance is superior to non-guided injection for the bicipital groove [4].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, affected shoulders show more cases of ultrasonographic impingement compared to unaffected shoulders [5].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there are no significant differences in supraspinatus tendon thickness between affected and unaffected shoulders [5].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there are no significant differences in subacromial bursa thickness between affected and unaffected shoulders [5].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there are no significant differences in acromio-humeral distance between affected and unaffected shoulders [5].
  • Intra-articular corticosteroid intervention provides clinically meaningful short-term improvements in adhesive capsulitis [6].
  • Intra-articular corticosteroid intervention administered after distension of the shoulder capsule provides clinically meaningful short-term improvements in adhesive capsulitis [6].
  • The acromial morphology classification system is an unreliable method to assess the acromion [23].
  • The acromial index shows no association with the presence of rotator cuff disease [23].
  • Imaging is an essential tool for the evaluation of patients with shoulder pain [26].
  • Understanding the extent of an injury with imaging is key to successful management of shoulder pain [26].
  • 94% of patients with spontaneous frozen shoulder recover to normal levels of function and motion without treatment [29].
  • Biomechanical studies indicate that the long head of the biceps contributes to stability of the glenohumeral joint in all directions [32].
  • In vivo studies have not yet established the stabilizing effect of the long head of the biceps on the glenohumeral joint [32].
  • The physiologic load required for the long head of the biceps to stabilize the glenohumeral joint remains unknown [32].
  • Pain reduction from subacromial injection causes shifts in scapulohumeral rhythm in patients with full-thickness rotator cuff tears [33].
  • Pain reduction from subacromial injection results in an increase in glenohumeral motion in patients with full-thickness rotator cuff tears [33].
  • Pain reduction from subacromial injection results in reduced reliance on scapular rotation in patients with full-thickness rotator cuff tears [33].
  • Addressing aberrant movement patterns and facilitating balanced activation of all shoulder muscles may be an appropriate treatment direction for subacromial pain syndrome [34].
  • Exercise protocols targeting the rotator cuff and scapular stabilizers are effective in improving pain, function, and shoulder active range of motion in patients with subacromial syndrome [35].
  • There are no between-group differences in shoulder maximal voluntary contraction (MVC) in subjects with subacromial impingement syndrome [36].
  • The use of a triaxial gyroscope is a simple, non-invasive, and reproducible method for recording shoulder anteflexion and abduction [37].
  • 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 [38].
  • Isometric measurement of shoulder rotation strength provides reliable information on the functional integrity of the rotator cuff muscles [39].
  • Functional integrity of the rotator cuff muscles, as measured by isometric shoulder rotation strength, is significantly related to patients' function and quality of life [39].
  • The majority of questions in commonly adopted shoulder-specific functional outcome measurement tools are subjective in nature [40].
  • The Shoulder Intervention Project (SIP) presents the rationale, design, methods, and operational aspects of a new rehabilitation approach to evaluate shoulder function and work disability after decompression surgery for subacromial impingement syndrome [47].
  • Acute experimental shoulder pain has an inhibitory effect on the activity of the infraspinatus during arm elevation [51].
  • All upper extremity-specific scales have acceptable psychometric properties for measuring rotator cuff tears [52].

Classification

  • Subacromial impingement syndrome is a specific diagnosis that must be differentiated from other conditions such as glenohumeral instability, particularly in younger athletes [13].
  • Impingement and rotator cuff syndromes were the most frequent diagnoses in population-based consultation patterns for shoulder pain [7].
  • There is no uniform definition for any of the diagnostic labels for shoulder pain, as revealed by the comparison of selection criteria from different randomised controlled trials [19].
  • Rotator cuff and subacromial bursa pathology were the most common findings on ultrasound and MRA in a prospective study of shoulder pain in primary care [14].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there were more cases of ultrasonographic impingement in affected shoulders compared to unaffected shoulders [5].
  • There were no significant differences in supraspinatus tendon thickness, subacromial bursa thickness, or acromio-humeral distance between affected and unaffected shoulders in patients with unilateral subacromial pain syndrome [5].
  • The acromial morphology classification system is an unreliable method to assess the acromion [23].
  • The acromial index shows no association with the presence of rotator cuff disease [23].
  • An extended inflammatory process is present in patients with subacromial impingement syndrome, involving not only the subacromial bursa but also the glenohumeral joint [9].
  • Increased levels of inflammatory markers are present in the subscapularis tendon and joint capsule in patients with subacromial impingement [9].
  • Abundant hemodynamic activity within the Bursa and AP resulted in severe motion pain that reflected focal bursitis, probably due to subacromial impingement and secondary glenohumeral synovitis [11].
  • A novel rat model of subacromial impingement creates cellular and molecular changes consistent with the development of rotator cuff tendinopathy [50].

Clinical Presentation

  • Impingement and rotator cuff syndromes are the most frequent diagnoses in patients with shoulder pain [7].
  • Rotator cuff and subacromial bursa pathology are the most common findings on ultrasound and magnetic resonance arthrography in patients with shoulder pain [14].
  • Subacromial impingement syndrome is a specific diagnosis that must be differentiated from other conditions such as glenohumeral instability, particularly in younger athletes [13].
  • Subacromial lipoma should be included in the differential diagnosis of rotator cuff impingement when conservative treatments fail [16].
  • A large ossified mass attached to the rotator cuff tendon in the subacromial bursa can cause impingement pain and restricted shoulder motion [21].
  • Symptoms of subacromial impingement can be caused by a rare benign soft tissue tumor, such as a collagenous fibroma located in the subacromial bursa [45].
  • Atypical presentations of calcific tendinitis, such as involvement of the teres minor, can affect overhead movement and present with isolated posterior shoulder pain [43].
  • 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 [17].
  • In patients with isolated unilateral subacromial pain syndrome and intact rotator cuff tendons, there are more cases of ultrasonographic impingement in affected shoulders compared to unaffected shoulders [5].
  • There are no significant differences in supraspinatus tendon thickness, subacromial bursa thickness, or acromio-humeral distance between affected and unaffected shoulders in patients with isolated unilateral subacromial pain syndrome [5].
  • Abundant hemodynamic activity within the bursa and anterior portal region results in severe motion pain that reflects focal bursitis, probably due to subacromial impingement and secondary glenohumeral synovitis [11].
  • An extended inflammatory process is present not only in the subacromial bursa but also in the glenohumeral joint in patients with subacromial impingement syndrome [9].

Investigations

  • Blind subacromial corticosteroid injections are as effective as ultrasound-guided injections for improving pain and function in subacromial impingement syndrome after short-term follow-up [1].
  • Ultrasound guidance is not superior to blind injection for subacromial bursa and glenohumeral joint injections regarding pain or function [4].
  • Ultrasound guidance is superior to blind injection for bicipital groove injections [4].
  • Patients with isolated unilateral subacromial pain syndrome have more cases of ultrasonographic impingement in the affected shoulder compared to the unaffected shoulder [5].
  • There are no significant differences in supraspinatus tendon thickness, subacromial bursa thickness, or acromio-humeral distance between affected and unaffected shoulders in patients with isolated unilateral subacromial pain syndrome [5].
  • Impingement and rotator cuff syndromes are the most frequent diagnoses in patients with shoulder pain [7].
  • An extended inflammatory process is present in the subscapularis tendon and joint capsule, in addition to the subacromial bursa, in patients with subacromial impingement syndrome [9].
  • Abundant hemodynamic activity within the bursa and anterior portal results in severe motion pain reflecting focal bursitis, likely due to subacromial impingement and secondary glenohumeral synovitis [11].
  • Subacromial impingement syndrome is a specific diagnosis that must be differentiated from other conditions such as glenohumeral instability, particularly in younger athletes [13].
  • Rotator cuff and subacromial bursa pathology are the most common findings on ultrasound and magnetic resonance arthrography (MRA) in patients with shoulder pain [14].
  • Subacromial lipoma should be included in the differential diagnosis of rotator cuff impingement when conservative treatments fail [16].
  • A large ossified mass attached to the rotator cuff tendon in the subacromial bursa can cause impingement pain and loss of motion, which resolves after surgical excision and repair [21].
  • Younger age is a good prognostic factor for the natural course of subacromial impingement syndrome [22].
  • Lower BMI is a good prognostic factor for the natural course of subacromial impingement syndrome [22].
  • More functional capacity is a good prognostic factor for the natural course of subacromial impingement syndrome [22].
  • A shorter symptomatic period is a good prognostic factor for the natural course of subacromial impingement syndrome [22].
  • Reversible changes on MRI are a good prognostic factor for the natural course of subacromial impingement syndrome [22].
  • Higher Constant and ASES scores at the first evaluation are good prognostic factors for the natural course of subacromial impingement syndrome [22].
  • Accurate diagnosis of the etiology of shoulder pain and proper injection technique are important in achieving satisfactory clinical outcomes with subacromial corticosteroid injections [25].
  • Imaging is an essential tool for the evaluation of patients with shoulder pain [26].
  • Understanding the extent of an injury with imaging is key to successful management of shoulder pain [26].
  • Magnetic resonance imaging (MRI) appearance of the shoulder after subacromial injection with corticosteroids can mimic a rotator cuff tear [41].
  • Caution should be used in the interpretation of MRI scans of the shoulder soon after the injection of corticosteroids [41].
  • MRI findings are significantly associated with the change in SPADI score from baseline to one-year follow-up in subacromial pain syndrome [53].
  • Patients with higher MRI total scores have a poorer outcome after treatment for subacromial pain syndrome [53].
  • Patients with tendinosis on MRI have a poorer outcome after treatment for subacromial pain syndrome [53].
  • Patients with bursitis on MRI have a poorer outcome after treatment for subacromial pain syndrome [53].

Treatment

Non-Operative Management

  • Blind subacromial corticosteroid injections are as effective as ultrasound-guided injections for improving pain and function in subacromial impingement syndrome after short-term follow-up [1].
  • Ultrasound guidance is not superior to blind injection for subacromial bursa injections regarding pain or function outcomes [4].
  • Subacromial injections of human placenta hydrolysate show significant improvement in pain, functional level, and quality of life in patients with shoulder impingement syndrome [3].
  • Subacromial injection of corticosteroids is an effective short-term therapy for symptomatic subacromial impingement syndrome [8].
  • There is little reproducible evidence to support the efficacy of subacromial corticosteroid injection in managing rotator cuff disease [27].
  • A single injection of 60 mg of ketorolac resulted in greater improvements in outcomes than a single injection of 40 mg triamcinolone for subacromial impingement at four weeks [44].
  • Subacromial hyaluronate injection produces similar pain and functional improvement to corticosteroid at short-term follow-up for impingement syndrome [20].
  • Subacromial autologous conditioned plasma (ACP) injections are a good alternative to subacromial cortisone injections, especially in patients with contraindications to cortisone [42].
  • Subacromial steroid injection is an alternative modality for primary frozen shoulder, and treatment should be individualized [12].
  • Specific exercise treatment for subacromial pain is effective and reduces the need for surgery, with maintained results after 10 years [18].
  • Management of subacromial impingement syndrome includes physical therapy, injections, and surgery for some patients [2].
  • The diagnostic labeling of shoulder pain lacks uniformity across randomized controlled trials [19].

Operative Management

  • Arthroscopic treatment should no longer be offered to people with subacromial impingement as surgery offers no discernible benefits but may result in harm, with evidence supporting nonoperative management or no treatment [15].
  • Following nonoperative treatment for at least 6 weeks, arthroscopic subacromial decompression (SAD) is a viable and good surgical option for shoulder impingement with an intact rotator cuff [24].
  • Surgery is indicated for persistent pain and loss of function despite conservative treatment in the patient care pathway for subacromial shoulder pain [49].
  • The short-term functional outcome of patients with calcific tendonitis after arthroscopic bursectomy and debridement is not influenced by whether it is performed in combination with or without subacromial decompression [10].

Differential Diagnosis

  • Subacromial lipoma should be included in the differential diagnosis of rotator cuff impingement when conservative treatments fail [16].

Complications

  • Arthroscopic treatment for subacromial impingement offers no discernible benefits and may result in harm [15].
  • Abundant hemodynamic activity within the subacromial bursa and anterior portal resulted in severe motion pain, reflecting focal bursitis likely due to subacromial impingement and secondary glenohumeral synovitis [11].
  • An extended inflammatory process is present not only in the subacromial bursa but also in the glenohumeral joint in patients with subacromial impingement syndrome [9].
  • A large ossified mass attached to the rotator cuff tendon in the subacromial bursa can cause impingement pain and loss of shoulder motion, requiring surgical excision and repair [21].

Recovery

  • Blind subacromial corticosteroid injections are as effective as ultrasound-guided injections for improving pain and function in subacromial impingement syndrome after short-term follow-up [1].
  • Subacromial injections of human placenta hydrolysate show significant improvement in pain, functional level, and quality of life in patients with shoulder impingement syndrome [3].
  • Intra-articular corticosteroid intervention, administered alone or after distension of the shoulder capsule, provides clinically meaningful short-term improvements in adhesive capsulitis of the shoulder [6].
  • Subacromial injection of corticosteroids is an effective short-term therapy for symptomatic subacromial impingement syndrome [8].
  • An extended inflammatory process is present in both the subacromial bursa and the glenohumeral joint capsule in patients with subacromial impingement syndrome [9].
  • The short-term functional outcome of patients with calcific tendonitis after arthroscopic bursectomy and debridement is not influenced by the addition of subacromial decompression [10].
  • Women aged 30 to 60 years with subacromial pain syndrome and a calcific deposit greater than 1.5 cm in length have the highest chance of suffering from symptomatic calcific tendinopathy of the rotator cuff [17].
  • Specific exercise treatment for subacromial pain is effective and reduces the need for surgery, with maintained results after 10 years [18].
  • Subacromial hyaluronate injection produces similar short-term pain and functional improvement to corticosteroid for impingement syndrome [20].
  • Younger age, lower BMI, more functional capacity, a shorter symptomatic period, reversible changes on MRI, and higher Constant and ASES scores at initial evaluation are good prognostic factors for the natural course of subacromial impingement syndrome [22].
  • The natural history of rotator cuff tendinopathy likely plays a significant role in long-term results, supporting the view that arthroscopic decompression is not recommended for its treatment [28].
  • 94% of patients with spontaneous frozen shoulder recover to normal levels of function and motion without treatment [29].
  • Arthroscopic acromioplasty provides no relevant additional clinical effects or impact on rotator cuff integrity compared to bursectomy alone at 12 years' follow-up for chronic subacromial pain syndrome [30].
  • Intraoperative ultrasound facilitates arthroscopic debridement of calcific rotator cuff tendinitis, with highly significant clinical improvement observed 2 weeks post-surgery and excellent radiological results until 9 months follow-up [31].
  • Arthroscopic acromioplasty significantly improves long-term clinical outcomes up to 2 years when combined with platelet-rich plasma injection for chronic rotator cuff tendinopathy [54].
  • Preoperative shoulder injections are associated with increased rotator cuff revision rates, with a correlation observed that is dependent on injection frequency and time [55].

Key Evidence

  • [L1] Blind injections into the subacromial bursa were as effective as ultrasound-guided injections for improving pain and function in subacromial impingement syndrome after a short-term follow-up. [1] (10.1177/0363546515618653)
  • [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] Subacromial injections showed significant improvement in pain, functional level, and quality of life in patients with shoulder impingement syndrome. [3] (10.1186/s12891-024-08266-4)
  • [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)
  • [L3] In this cohort of patients with isolated unilateral SAPS, we found more cases of ultrasonographic impingement in affected shoulders compared to unaffected, but no significant differences in supraspinatus tendon thickness, subacromial bursa thickness, or acromio-humeral distance. [5] (10.1016/j.jse.2025.02.020)
  • [L1] Intra-articular corticosteroid intervention, administered either alone or after distension of the shoulder capsule, provided clinically meaningful improvements in the short term. [6] (10.1177/0363546518823337)
  • [L3] Impingement and rotator cuff syndromes were the most frequent diagnoses. [7] (10.1186/1471-2474-13-238)
  • [L1] Subacromial injection of corticosteroids is an effective short-term therapy for the treatment of symptomatic subacromial impingement syndrome. [8] (10.2106/00004623-199611000-00007)
  • [L3] This study provides evidence that an extended inflammatory process is present, not only in the subacromial bursa but also in the glenohumeral joint in patients with subacromial impingement syndrome. [9] (10.1007/s00167-020-05992-9)
  • [L1] This study has demonstrated that the short-term functional outcome of patients with calcific tendonitis after arthroscopic bursectomy and debridement of the calcific deposit is not influenced if performed in combination with or without a subacromial decompression. [10] (10.1016/j.arthro.2015.05.015)
  • [L4] Abundant hemodynamic activity within the Bursa and AP resulted in severe motion pain that reflected focal bursitis, probably due to subacromial impingement and secondary glenohumeral synovitis. [11] (10.1016/j.jse.2025.04.023)
  • [L1] Subacromial steroid injection is an alternative modality, and treatment should be individualized. [12] (10.1016/j.jse.2011.04.029)
  • [L2] Rotator cuff and subacromial bursa pathology were the most common findings on ultrasound and MRA. [14] (10.1186/1471-2474-12-119)
  • [L5] Arthroscopic treatment should no longer be offered to people with subacromial impingement as surgery offers no discernible benefits but may result in harm, and the weight of evidence supports nonoperative management or no treatment. [15] (10.1016/j.arthro.2022.03.017)
  • [Case_report] Subacromial lipoma should be included in the differential diagnosis of rotator cuff impingement when conservative treatments fail. [16] (10.1016/j.jse.2008.09.017)
  • [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. [17] (10.1016/j.jse.2015.02.024)
  • [L2] Specific exercise treatment for patients with subacromial pain was effective and reduced the need for surgery with maintained results after 10 years. [18] (10.1016/j.jse.2024.10.027)
  • [L2] The comparison of selection criteria from different randomised controlled trials revealed no uniform definition for any of the diagnostic labels for shoulder pain. [19] (10.1016/j.math.2008.04.005)
  • [L2] A subacromial hyaluronate injection to treat impingement syndrome produces similar pain and functional improvement to corticosteroid at a short-term follow-up. [20] (10.1016/j.jse.2011.11.009)
  • [L4] A large ossified mass attached to the rotator cuff tendon in the subacromial bursa was successfully treated with surgical excision and repair, resulting in the resolution of impingement pain and restoration of shoulder motion by 12 months. [21] (10.1097/01.blo.0000170720.91461.58)
  • [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. [22] (10.1016/j.jse.2015.06.007)
  • [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. [23] (10.1016/j.jse.2011.09.028)
  • [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. [24] (10.1016/j.arthro.2019.06.012)
  • [L5] Accurate diagnosis of the etiology of a patient's shoulder pain and proper injection technique are important in achieving satisfactory clinical outcomes. [25] (10.1016/j.jse.2007.07.009)
  • [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. [26] (10.1016/j.csm.2013.03.009)
  • [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. [27] (10.5435/00124635-200701000-00002)
  • [L1] The natural history of rotator cuff tendinopathy probably plays a significant role in the results in the long-term. [28] (10.1302/0301-620x.99b6.bjj-2016-0569.r1)
  • [L4] We found 94% of patients with spontaneous frozen shoulder recovered to normal levels of function and motion without treatment. [29] (10.1007/s11999-011-2176-4)
  • [L2] There were no relevant additional effects of arthroscopic acromioplasty on bursectomy alone with respect to clinical outcomes and rotator cuff integrity at 12 years' follow-up. [30] (10.1016/j.jse.2017.03.021)
  • [L1] Highly significant clinical improvement of the shoulder was already observed in the entire population 2 weeks after surgery, with excellent radiological results observed until the 9 months follow-up. [31] (10.1007/s00402-014-1927-6)
  • [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. [32] (10.1016/j.arthro.2010.10.014)
  • [L3] Pain reduction caused shifts in scapulohumeral rhythm resulting in an increase in glenohumeral motion and a reduced reliance on scapular rotation. [33] (10.1016/j.jse.2007.05.010)
  • [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] Both interventions are effective in terms of pain, function, and shoulder active range of motion. [35] (10.1016/j.jht.2017.11.041)
  • [L3] No between-group differences in shoulder MVC were observed. [36] (10.1002/mus.20636)
  • [L3] The use of a tri axial gyroscope is a simple non invasive and reproducible method for the recording of shoulder anteflexion and abduction. [37] (10.1186/1471-2474-13-135)
  • [L4] The KSS is a useful measurement tool that combines subjective and objective evaluations for shoulder function related to rotator cuff disorders. [38] (10.1016/j.jse.2008.11.019)
  • [L3] Isometric measurement of shoulder rotation strength provides reliable information on the functional integrity of the rotator cuff muscles, which is significantly related to patients' function and quality of life. [39] (10.1016/j.jse.2004.03.009)
  • [L1] The majority of questions posed in the most commonly adopted shoulder-specific functional outcome measurement tools were subjective in nature and may account for part of the phenomenon. [40] (10.1007/s00264-007-0493-8)
  • [L4] One should use caution in the interpretation of magnetic resonance imaging scans of the shoulder soon after the injection of corticosteroids. [41] (10.1016/j.arthro.2007.01.024)
  • [L3] Therefore, subacromial ACP injections are a good alternative to subacromial cortisone injections, especially in patients with contraindication to cortisone. [42] (10.1007/s00167-015-3651-3)
  • [Case_report] This case highlights the importance of considering atypical presentations of calcific tendinitis, particularly in the context of isolated posterior shoulder pain. [43] (10.1016/j.jisako.2025.101055)
  • [L1] In this study, a single injection of 60 mg of ketorolac resulted in improvements in outcomes greater than a single injection of 40 mg triamcinolone for the treatment of subacromial impingement when assessed at four weeks. [44] (10.1016/j.jse.2012.08.026)
  • [L4] In this case, the symptoms were caused by a rare benign soft tissue tumor: a collagenous fibroma located in the subacromial bursa. [45] (10.1016/j.jse.2010.04.009)
  • [L1] The paper presents the rationale, design, methods, and operational aspects of the Shoulder Intervention Project (SIP) to evaluate a new rehabilitation approach. [47] (10.1186/1471-2474-15-215)
  • [L5] The document outlines a patient care pathway for subacromial shoulder pain emphasizing shared decision-making, continuity of care, and a stepwise approach from primary to secondary care, noting that surgery is indicated for persistent pain and loss of function despite conservative treatment. [49] (10.1177/1758573215576456)
  • [L5] This new rat subacromial impingement model creates cellular and molecular changes consistent with the development of rotator cuff tendinopathy. [50] (10.1016/j.jse.2022.02.041)
  • [L5] This study demonstrates that acute experimental shoulder pain has an inhibitory effect on the activity of the infraspinatus during arm elevation. [51] (10.1016/j.jse.2016.09.005)
  • [L3] All upper extremity-specific scales had acceptable psychometric properties. [52] (10.1097/corr.0000000000000800)
  • [L2] In this study, MRI findings were significantly associated with the change in the SPADI score from baseline and to one year follow-up, with a poorer outcome after treatment for the patients with higher MRI total score, tendinosis and bursitis on MRI. [53] (10.1186/s12891-017-1827-3)
  • [L1] Arthroscopic acromioplasty significantly improves long-term clinical outcomes up to 2 years. [54] (10.1177/0363546515608485)
  • [L3] This study strongly suggests a correlation between preoperative shoulder injections and revision rotator cuff repair, with frequency and time dependence observed. [55] (10.1016/j.arthro.2018.10.116)

References

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DOI: 10.1016/j.jse.2025.02.020 [6] Efficacy of Pharmacological Therapies for Adhesive Capsulitis of the Shoulder: A Systematic Review and Network Meta-analysis. The American Journal of Sports Medicine. 2019. DOI: 10.1177/0363546518823337 [7] Population-based consultation patterns in patients with shoulder pain diagnoses. BMC Musculoskeletal Disorders. 2012. DOI: 10.1186/1471-2474-13-238 [8] Efficacy of Injections of Corticosteroids for Subacromial Impingement Syndrome. The Journal of Bone & Joint Surgery. 1996. DOI: 10.2106/00004623-199611000-00007 [9] Increased levels of inflammatory markers in the subscapularis tendon and joint capsule in patients with subacromial impingement. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-05992-9 [10] Short‐Term Outcome After Arthroscopic Bursectomy Debridement of Rotator Cuff Calcific Tendonopathy With and Without Subacromial Decompression: A Prospective Randomized Controlled Trial. Arthroscopy. 2015. DOI: 10.1016/j.arthro.2015.05.015 [11] Impact of hemodynamics in individual shoulder structures on pain intensity in patients with rotator cuff tear. Journal of Shoulder and Elbow Surgery. 2026. DOI: 10.1016/j.jse.2025.04.023 [12] Comparison of glenohumeral and subacromial steroid injection in primary frozen shoulder: a prospective, randomized short-term comparison study. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2011.04.029 [13] BIGLIANI, LOUIS U. M.D.+, NEW YORK, N.Y.; LEVINE, WILLIAM N. M.D.++, BALTIMORE, MARYLAND. The Journal of Bone and Joint Surgery. American Volume. 1997. [14] A prospective study of shoulder pain in primary care: Prevalence of imaged pathology and response to guided diagnostic blocks. BMC Musculoskeletal Disorders. 2011. DOI: 10.1186/1471-2474-12-119 [15] Editorial Commentary : Arthroscopic Treatment Should No Longer Be Offered to People With Subacromial Impingement. Arthroscopy. 2022. 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Clinics in Sports Medicine. 2013. DOI: 10.1016/j.csm.2013.03.009 [27] 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 [28] Arthroscopic decompression not recommended in the treatment of rotator cuff tendinopathy. The Bone & Joint Journal. 2017. DOI: 10.1302/0301-620x.99b6.bjj-2016-0569.r1 [29] The Natural History of Idiopathic Frozen Shoulder: A 2- to 27-year Followup Study. Clinical Orthopaedics & Related Research. 2012. DOI: 10.1007/s11999-011-2176-4 [30] Does acromioplasty result in favorable clinical and radiologic outcomes in the management of chronic subacromial pain syndrome? A double-blinded randomized clinical trial with 9 to 14 years' follow-up. Journal of Shoulder and Elbow Surgery. 2017. 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Journal of Shoulder and Elbow Surgery. 2010. DOI: 10.1016/j.jse.2010.04.009 [47] Shoulder function and work disability after decompression surgery for subacromial impingement syndrome: a randomised controlled trial of physiotherapy exercises and occupational medical assistance. BMC Musculoskeletal Disorders. 2014. DOI: 10.1186/1471-2474-15-215 [49] Subacromial shoulder pain. Shoulder & Elbow. 2015. DOI: 10.1177/1758573215576456 [50] Evaluating the role of subacromial impingement in rotator cuff tendinopathy: development and analysis of a novel rat model. Journal of Shoulder and Elbow Surgery. 2022. DOI: 10.1016/j.jse.2022.02.041 [51] The influence of induced shoulder muscle pain on rotator cuff and scapulothoracic muscle activity during elevation of the arm. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2016.09.005 [52] Which Is the Best Outcome Measure for Rotator Cuff Tears?. Clinical Orthopaedics & Related Research. 2019. 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b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.