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弹响肩胛

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Updated Oct 2026
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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

弹响肩胛是指当您的肩胛骨在胸壁上活动时，您听到或感觉到肩胛骨发出摩擦声、咔哒声或弹响声。医生有时称之为“搓衣板综合征”，因为这种声音感觉就像轮子在搓衣板上滚过。这种声音本身很常见。在完全没有任何症状的人群中，约三分之一的人肩胛骨会发出一定的摩擦声。如果只有声音而没有疼痛，则无需治疗。

通常促使人们就医的是疼痛。疼痛位于肩胛骨周围或下方，常常靠近最接近脊柱的内侧缘。在进行过头活动、向上伸手或跨过身体伸手时，疼痛往往会加重，也可能表现为运动表现下降。疼痛来自发炎的滑囊（一种薄薄的、充满液体的衬垫，可让肩胛骨在肋骨上平滑滑动），或来自骨骼本身的形状。胸壁就像一个音箱，因此您听到的声音比引起它的活动更响亮。

疼痛会让日常事务变得困难。把沉重的锅举到高处的架子上、在晾衣绳上晾衣服或伸手去拉安全带，都可能诱发疼痛。有些人发现疼痛在活动之后比活动期间更明显。疼痛可能严重到干扰睡眠，或使您无法正常使用手臂。

如果您的症状没有缓解、在数周内逐渐加重、在夜间把您痛醒，或使您无法工作或使用手臂，请去看您的全科医生或要求专科医生评估。

实际发生了什么

您的肩胛骨天生就是用来滑动的。它贴在胸壁上，与胸壁之间隔着一层薄薄的、光滑的脂肪组织，这层组织就像两个活动面之间的垫圈。四个关节协同工作来活动您的肩部，其中约三分之二的活动来自球窝关节本身，其余三分之一来自肩胛骨在肋骨上的滑动。当这种滑动顺畅时，您根本不会察觉到它。

弹响肩胛的问题在于有某种因素干扰了这种滑动。有时是骨骼的形状：肩胛骨的内侧缘可能比平常更向肋骨方向倾斜或弯曲，因此它比应有的位置更贴近胸壁。有时是肩胛骨上长出了一小块多余的骨质。很多时候是肩胛骨周围的肌肉用力不均衡，使肩胛骨在您活动时无法平稳地移动。上述任何一种情况都可能使肩胛骨发生摩擦或卡住，而不是顺畅地滑动。

这种摩擦会刺激肩胛骨与肋骨之间的衬垫。这个衬垫称为滑囊，是一个薄薄的、充满液体的囊，在骨骼与软组织之间起到减震器的作用。当滑囊发炎时，它会增厚并出现压痛，这就是您在肩胛骨下方或周围感受到的疼痛。摩擦还可能导致组织本身发生反应性增厚，这是身体对反复摩擦的反应。

这解释了上文描述的症状。声音来自粗糙的表面相互摩擦，而胸壁像音箱一样把声音放大。疼痛来自发炎的衬垫，而不是来自声音本身。这就是为什么这两个问题的治疗方式不同，也是为什么治疗的重点在于平息炎症，并重新训练控制肩胛骨的肌肉。

我们能做什么

Mater Private Hospital Rockhampton 的上肢外科医生 Kieran Hirpara 医生会从适合您病情的最微创方案入手。患者通常由全科医生转诊至我们的诊所；如果物理治疗师建议您就诊，您仍需获得全科医生的转诊，才有资格享受 Medicare 报销。在诊所，我们会采集病史、检查您的肩部，并在需要时安排影像学检查，以查明引起声音和疼痛的原因。

大多数人无需手术即可好转，因此治疗从非手术方法开始。第一步是进行物理治疗计划，加强控制肩胛骨的肌肉，同时拉伸已经变紧的肌肉。改变诱发症状的活动也有帮助。在考虑任何进一步治疗之前，请给予这些方法3至6个月的充分尝试。

如果疼痛持续存在，药物可以帮助平息炎症。抗炎药片（与许多人用于缓解肌肉酸痛的药物属于同一类）是这一阶段治疗的一部分。我们还可以在影像引导下，将类固醇和局部麻醉药注射到肩胛骨下方的滑囊中。这样做有两个作用：既能平息发炎的衬垫，又能确认您的疼痛确实来自这里。

只有当疼痛在接受上述治疗数月后仍然持续、且这些治疗未能带来足够改善时，才会考虑手术。手术采用微创（锁孔）方式，通过小切口借助摄像头进行。手术会切除肩胛骨与肋骨之间发炎的滑囊。只有在术中发现肩胛骨的内上角突出时，才会对其进行修整。大多数人术后疼痛会明显改善，但常常仍会残留一些咔哒声。我们会与您详细讨论手术对您意味着什么，并共同决定手术是否是合适的下一步。

预期情况

大多数人无需手术即可好转。治疗从物理治疗开始，以加强控制肩胛骨的肌肉，同时配合抗炎药物，并改变诱发症状的活动。请给予这些方法3至6个月的充分尝试。许多人发现在此期间疼痛逐渐减轻，从而永远不需要手术。

如果在接受上述治疗数月后疼痛仍持续，可能会考虑手术。微创（锁孔）手术会切除肩胛骨与肋骨之间发炎的滑囊，并且只有在发现肩胛骨内上角突出时才对其进行修整。大多数人术后疼痛会明显改善。但常常仍会残留一些咔哒声，因为有助于缓解疼痛的治疗主要解决的是疼痛，而不是声音。所有症状完全消失并不是通常的结果。

如果不进行治疗，症状可能会持续存在，并可能严重到干扰睡眠或使您无法正常使用手臂。这种疾病可能难以识别和治疗，因此值得尽早获得明确诊断，而不是等待它自行好转。

如果您的症状没有缓解、在数周内逐渐加重、在夜间把您痛醒，或使您无法工作或使用手臂，请去看您的全科医生或要求专科医生评估。

何时就医

仅有声音并不需要担心。在完全没有任何症状的人群中，约三分之一的人肩胛骨会发出一定的摩擦声，如果只有声音，则无需治疗。重要的是疼痛。如果您的肩胛骨周围或下方出现疼痛，且疼痛没有缓解、在数周内逐渐加重、在夜间把您痛醒，或使您无法工作或使用手臂，请去看您的全科医生或要求专科医生评估。如果疼痛严重到干扰睡眠、您的运动表现有所下降，或过头活动（例如向上伸手或跨过身体伸手）会诱发疼痛，也请要求评估。弹响肩胛可能难以识别，因此尽早获得明确诊断是值得的。

深入探讨

Advanced reading: the deeper science (optional)

本节内容超出了您为自身治疗做决定所需了解的范围。弹响肩胛值得多读一些，因为声音和疼痛是两个不同的问题，而有效的治疗主要解决的是后者，而不是前者。

声音很常见，疼痛才是问题

肩胛骨发出的摩擦声本身并不是疾病的征象。一篇关于该病的经典综述引用了一项早期研究，该研究发现在100名完全没有任何症状的人中，31%存在肩胛骨摩擦音 [1]。使声音变成一种疾病的是疼痛，通常来自发炎的滑囊：一层薄薄的、内衬液体的组织，可让肩胛骨在肋骨上滑动。

骨骼形状也有一定作用。在一项影像学研究中，肩胛骨沿内侧缘向前弯曲（呈凹形，“肩胛骨内侧体角”为正值）的人，发生弹响肩胛的风险高出12倍 [2]。这项测量后来证明并不像最初看起来那么有用：随后的一项研究发现，这个角度会因观察方向不同而有相当大的差异，因此它不够可靠，不能单凭它来诊断该病 [3]。在一项尸体模型研究中，最重要的骨性特征是肩胛骨内侧部分向前朝肋骨方向突出的程度 [4]。

大多数人无需手术即可好转

在一项研究中，28名患者的30侧肩胛骨接受了一项专门的肌肉强化训练计划，其中14侧（50%）仅靠锻炼就取得了良好效果，6侧（21%）只需额外加用抗炎药物，因此按照该研究自身的评分标准，71%无需手术即达到良好或更好的结果 [5]。

随访时间最长的研究来自芬兰。十二名接受开放手术的患者和9名接受非手术治疗的患者，在平均22年后接受了重新评估。两组用力时的疼痛都很低：手术组为0.8分（满分10分），非手术组为1.5分（满分10分），这一差异太小，无法确定是否真实存在（p = 0.357）[6]。在手术患者中，12名中有7名术后疼痛迅速改善，但从长远来看，两种途径的最终结果大致相同。

向滑囊内注射局部麻醉药和类固醇有两个作用：既能治疗炎症，又能检验滑囊是否真的是疼痛来源。在英国的一项诊疗路径中，94名患者中有74名在物理治疗后仍有困扰，并接受了超声引导下注射；其中55名初始反应良好，17名的效果得以持续 [7]。在接受随访的42名手术患者中，对注射反应良好的患者术后改善程度大于反应不佳的患者 [7]。一项规模更大、随访至少五年的美国研究并未发现同样的关联 [8]，因此注射反应不佳并不意味着排除手术。

手术能实现什么，不能实现什么

规模最大的长期研究对66名接受微创（锁孔）滑囊切除及肩胛骨角部修整的患者随访了5至15年。平均肩关节评分从56.7分升至87.2分（满分100分），疼痛从5.2分降至1.4分（满分10分），77.6%的患者获得了足以察觉的改善。在42名参加运动的患者中，38名（90.5%）重返运动，31名（73.8%）恢复到或接近以前的水平。八名（12.1%）需要再次手术 [8]。另一项纳入74侧肩胛骨的研究，再次手术率相近（74侧中有8侧），并发现年龄较大、症状持续时间较长以及术前心理健康评分较低的患者，效果往往较差 [9]。

症状完全消失是少数情况。一项纳入203个手术肩部的系统综述发现，42个（20.7%）完全康复，139个（68.5%）有所改善但仍有一些症状，22个（10.8%）效果不佳 [10]。2026年一项纳入464名患者的综述得出了相同的总体结论：非手术治疗和手术治疗都能缓解疼痛，但机械性症状，即咔哒声和摩擦声，往往不会完全消失 [11]。

骨头值得切除吗？

修整肩胛骨内上角是该手术的传统组成部分，因此它可能作用不大这一点令人意外。一家医疗中心比较了24名仅切除滑囊的患者和32名同时修整角部的患者。两组最终疼痛评分（3.4分和2.8分，满分10分，p = 0.351）和肩关节评分（75.8分和76.5分，p = 0.895）相同，且分别有58%和59%的患者仍有咔哒声 [12]。不处理骨质时手术时间更短：37.5分钟对比61.2分钟 [12]。两组的随访时间不同，且并非随机分组，因此这并不是定论，但这正是为什么修整骨质的决定是在术中而不是事先做出的原因。

参考文献

[1] Kuhn JE, Plancher KD, Hawkins RJ. Symptomatic Scapulothoracic Crepitus and Bursitis. J Am Acad Orthop Surg. 1998;6(5):267-73. https://doi.org/10.5435/00124635-199809000-00001 [2] Spiegl UJ, Petri M, Smith SW, Ho CP, Millett PJ. Association between scapula bony morphology and snapping scapula syndrome. J Shoulder Elbow Surg. 2015;24(8):1289-95. https://doi.org/10.1016/j.jse.2014.12.034 [3] Percin B, Featherall J, Tashjian RZ, Chalmers PN, Joyce CD, Mortensen AJ, et al. The influence of scapular orientation on the medial scapula corpus angle in snapping scapula syndrome. JSES Int. 2025;9(1):70-8. https://doi.org/10.1016/j.jseint.2024.08.179 [4] Tahal DS, Katthagen JC, Marchetti DC, Mikula JD, Montgomery SR, Brady A, et al. A Cadaveric Model Evaluating the Influence of Bony Anatomy and the Effectiveness of Partial Scapulectomy on Decompression of the Scapulothoracic Space in Snapping Scapula Syndrome. Am J Sports Med. 2017;45(6):1276-82. https://doi.org/10.1177/0363546516687755 [5] Groh G, Simoni M, Allen T, Dwyer T, Heckman M, Rockwood C. Treatment of snapping scapula with a periscapular muscle strengthening program. J Shoulder Elbow Surg. 1996;5(2):S6. https://doi.org/10.1016/s1058-2746(96)80089-9 [6] Vastamäki M, Vastamäki H. Open Surgical Treatment for Snapping Scapula Provides Durable Pain Relief, but so Does Nonsurgical Treatment. Clin Orthop Relat Res. 2016;474(3):799-805. https://doi.org/10.1007/s11999-015-4614-1 [7] Tytherleigh-Strong G, Gill J, Griffiths E, Al-Hadithy N. Prognosis After Arthroscopic Superior Medial Scapuloplasty for Snapping Scapula Syndrome Improves After a Transient Beneficial Response With an Ultrasound-Guided Subscapular Cortisone Injection. Arthroscopy. 2020;36(12):2965-72. https://doi.org/10.1016/j.arthro.2020.07.024 [8] Rupp M, Geissbuhler AR, Rutledge JC, Amendola R, Hanson JA, Doan KC, et al. Minimum 5-Year Clinical and Return-to-Sport Outcomes After Primary Arthroscopic Scapulothoracic Bursectomy and Partial Scapulectomy for Snapping Scapula Syndrome. Am J Sports Med. 2024;52(6):1449-56. https://doi.org/10.1177/03635465241243072 [9] Menge TJ, Horan MP, Tahal DS, Mitchell JJ, Katthagen JC, Millett PJ. Arthroscopic Treatment of Snapping Scapula Syndrome: Outcomes at Minimum of 2 Years. Arthroscopy. 2016;33(4):726-32. https://doi.org/10.1016/j.arthro.2016.08.029 [10] Memon M, Kay J, Simunovic N, Ayeni OR. Arthroscopic management of snapping scapula syndrome improves pain and functional outcomes, although a high rate of residual symptoms has been reported. Knee Surg Sports Traumatol Arthrosc. 2017;26(1):221-39. https://doi.org/10.1007/s00167-017-4693-5 [11] Wallace K, Mitchell JK, Lauck BJ, Reed J, Conlon S, Kamath GV. Snapping Scapula Syndrome: A Systematic Review of Treatment Options and Outcomes. J Shoulder Elbow Surg. 2026. https://doi.org/10.1016/j.jse.2026.05.023 [12] Featherall J, Christensen GV, Mortensen AJ, Wheelwright JC, Chalmers PN, Tashjian RZ. Arthroscopic scapulothoracic bursectomy with and without superomedial angle scapuloplasty: a comparison of patient-reported outcomes. J Shoulder Elbow Surg. 2023;32(9):1945-52. https://doi.org/10.1016/j.jse.2023.03.020

Reviewed by AI synthesis (v2) — pending human review · 4 October 2026.

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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

  • Snapping scapula syndrome is caused by either osseous lesions or scapulothoracic bursitis [3].
  • The condition is also referred to as “washboard syndrome” and is attributed to bony and soft tissue abnormalities [9].
  • Snapping scapula represents the clinical expression of scapulothoracic impingement due to mechanical factors and/or muscle imbalance [7].
  • Osteochondroma of the scapula is a rare entity that may present with snapping scapula syndrome when it alters scapulothoracic mechanics [6].
  • Snapping scapula syndrome can be a debilitating disorder [2].
  • Diagnosis and management of snapping scapula syndrome remains challenging despite recent advances [1].
  • The condition can be difficult to recognize and treat [3].
  • Four-dimensional computed tomography scans facilitate preoperative planning by defining pathology and improving assessment of the amount and location of scapular bone and soft tissue causing symptoms [18].

Treatment

  • Treatment of patients with snapping scapula syndrome begins with nonoperative methods [5].
  • When nonoperative treatment fails, several surgical options exist [5].
  • Arthroscopic management of snapping scapula syndrome yields improvement in pain, crepitus, and range of motion in a majority of patients [4].
  • Most patients experience residual symptoms following arthroscopic management [4].
  • Arthroscopic scapulothoracic treatment provides significant pain relief and functional improvement for painful snapping scapula symptoms not responding to non-surgical treatment modalities [8].
  • Arthroscopic treatment for snapping scapula syndrome resulted in significant improvement in pain and function with high patient satisfaction at a mean follow-up of 3.4 years [14].
  • Arthroscopic scapuloplasty leads to significant improvement in pain and function in patients with snapping scapula syndrome refractory to conservative treatment [15].
  • Arthroscopic surgery is an effective treatment for snapping scapula syndrome in both primary and revision cases, showing significant improvements in all postoperative outcome scores at a mean of 3.4 years [17].
  • Arthroscopic resection of the superomedial corner of the scapula is a useful technique in patients whose pain and clicking can be clinically localized and who have failed to respond to conservative measures [19].
  • Arthroscopic resection of the medial superior hook formation in combination with partial bursectomy provided good results with significant gains with respect to the WORC score in 90 % of the patients troubled by painful snapping scapula for a long time and without relief by exercise-based rehabilitation [35].
  • At the end of 1 year, all patients in a case series had a constant score above 90 and were completely relieved of snapping around the scapula having full pain-free movements at the shoulder and scapulothoracic joints [11].
  • A patient remained asymptomatic with full range of motion and no further complaints of pain or snapping at twenty-six months postoperatively [12].
  • At 2 years 6 months after the operation, snapping and pain were completely gone and the patient was satisfied with the results [13].

Anatomy & Pathophysiology

Etiology and Mechanism

  • Snapping scapula is the clinical expression of scapulothoracic impingement due to mechanical factors and/or muscle imbalance [7].
  • The condition is attributed to bony and soft tissue abnormalities [9].
  • Osteochondroma of the scapula may present with snapping scapula syndrome when it alters scapulothoracic mechanics [6].
  • Subscapular elastofibroma is a reactive pseudotumor resulting from mechanical friction of the scapula on the chest wall [86].

Bony Anatomy and Morphology

  • The scapula is separated from the chest wall by thin gliding fibro-fatty tissue, allowing its smooth excursion over the chest wall [53].
  • Anterior angulation of the medial scapula in the axial plane was associated with snapping scapula syndrome [34].
  • Patients with a concave-shaped scapula and a positive medial scapula corpus angle may be at risk for snapping scapula syndrome [47].
  • The anterior offset of the scapula appeared to be the most important bony parameter to consider during preoperative planning and the evaluation of scapulothoracic space decompression with partial scapulectomy [46].
  • The weakest area of the circumference of the biomechanical body of the scapula is the connection of the scapular spine and the medial border of the scapula, known as the spinomedial angle [53].
  • The superior angle and the adjacent part of the supraspinous fossa form an appendage that serves as a surface of insertion or origin of muscles but does not transmit compressive forces from the glenoid [53].

Soft Tissue and Neurovascular Anatomy

  • Neurologic structures around the scapula vary significantly between the neutral arm position and the chicken-wing position commonly used in the arthroscopic treatment of snapping scapula syndrome [85].
  • The scapula is attached to the axial skeleton by the clavicle, specifically by the acromioclavicular and sternoclavicular joints [53].
  • The scapula serves for attachment of a number of muscles originating from the axial skeleton that control its motion [53].

Classification

  • Mauclaire classified scapulothoracic crepitus into three types: froissement (a gentle friction sound thought to be physiologic), frottement (a louder sound with grating, which is usually pathologic), and craquement (a loud snapping sound, which is always pathologic) [26].
  • Frottement may suggest a soft-tissue lesion or bursitis, while craquement may suggest an osseous lesion as the source of symptomatic scapulothoracic crepitus [26].
  • The snapping scapula syndrome is caused by either osseous lesions or scapulothoracic bursitis [3].
  • Snapping scapula is the clinical expression of the scapulothoracic impingement due to mechanical factors and/or muscle imbalance [7].
  • The snapping scapula, also called “washboard syndrome,” is a controversial condition attributed to bony and soft tissue abnormalities [9].
  • Rib fractures at the posterior angle could cause snapping scapula syndrome [20].

Clinical Presentation

  • Snapping scapula syndrome is an uncommon condition that is likely underdiagnosed [42].
  • The condition can produce severe shoulder pain and dysfunction [24].
  • Patients often present with decreased athletic performance and increased pain with overhead activities [42].
  • Crepitus is a reported symptom in patients with snapping scapula syndrome [42].
  • High clinical suspicion is necessary in patients presenting with medial scapular border tenderness, palpable crepitus, and audible snapping [40].
  • Potential factors causing snapping scapula syndrome include bony prominence at the superomedial scapular angle, imbalance of the periscapular muscles, and scapulothoracic bursitis [42].
  • Scapulothoracic crepitus is not necessarily a pathologic condition, as it was found in 31% of 100 normal asymptomatic persons [26].
  • Scapulothoracic crepitus is considered pathologic if it is associated with pain, winging, or other disorders of the scapulothoracic articulation [26].
  • The condition has been referred to by various names, including snapping scapula, washboard syndrome, scapulothoracic syndrome, rolling scapula, grating scapula, and scapulocostal syndrome [26].
  • Mauclaire classified scapulothoracic crepitus into three types: froissement (gentle friction sound), frottement (louder sound with grating), and craquement (loud snapping sound) [26].
  • Scapular noises arise from anatomic changes in the tissue interposed between the scapula and the chest wall and/or an incongruent scapulothoracic articulation [26].
  • The air-filled thoracic cavity acts as a resonating chamber that amplifies scapulothoracic crepitus [26].
  • A mass composed of alternating strands of fatty and fibrous tissue located at the inferior pole of the scapula is pathognomonic for elastofibroma dorsi [36].
  • Scapular osteochondroma is a rarely reported cause of scapular pseudo-winging and should be considered in the differential diagnosis when winging and a mass are present [43].
  • The differential diagnosis for causes of snapping scapula includes idiopathic causes, scapulothoracic bursitis, osteochondromas, and elastofibromas [42].
  • Four-dimensional computed tomography scans facilitate preoperative planning by defining pathology and assessing the amount and location of scapular bone and soft tissue causing symptoms [18].
  • Plain radiographs and CT scans provide detailed information about osseous abnormalities in snapping scapula syndrome [42].
  • MRI characterizes bursal and other soft-tissue pathologies in snapping scapula syndrome [42].

Investigations

  • Symptomatic scapulothoracic crepitus is considered pathologic when associated with pain, winging, or other disorders of the scapulothoracic articulation [26].
  • Scapulothoracic crepitus is attributed to anatomic changes in the tissue interposed between the scapula and the chest wall or an incongruent scapulothoracic articulation [26].
  • The air-filled thoracic cavity acts as a resonating chamber that amplifies scapulothoracic crepitus noises [26].
  • Frottement (a louder sound with grating) usually suggests a soft-tissue lesion or bursitis, while craquement (a loud snapping sound) always suggests an osseous lesion [26].
  • Four-dimensional computed tomography (4D CT) scans define pathology well and improve the assessment of the amount and location of scapular bone and soft tissue causing symptoms in snapping scapula syndrome [18].
  • Fluoroscopy provides a real-time method for evaluating and documenting abnormal osseous mechanics of the scapulothoracic bursal region [31].
  • Anterior angulation of the medial scapula in the axial plane is associated with snapping scapula syndrome [34].
  • The anterior offset of the scapula is the most important bony parameter to consider during preoperative planning and evaluation of scapulothoracic space decompression with partial scapulectomy [46].
  • Imaging-guided injections provide an alternative means of diagnosis in cases where direct imaging is usually not successful [48].
  • Rib fractures at the posterior angle can cause snapping scapula syndrome [20].

Treatment

Non-Operative Management

  • In most cases, nonoperative treatment is curative and includes physical therapy for scapular muscle strengthening and nonsteroidal anti-inflammatory medications [29].
  • Nonsurgical management remains the first treatment option, with surgery recommended after 6 months of nonsurgical treatment with no improvement [42].
  • Nonoperative management of snapping scapula syndrome in the form of analgesia, physiotherapy, local corticosteroid injection, and/or extracorporeal shockwave therapy should be initiated for 3 to 6 months before considering surgical management [40].
  • Strengthening weak periscapular muscle groups combined with simultaneous stretching of contracted muscles and training of antagonistic muscle groups can yield good clinical results [42].
  • Physical therapy, injections with local anesthetics and/or steroids, and NSAIDs can be useful in nonsurgical management [42].
  • Patients treated nonsurgically achieved results that were not distinguishable from the surgically treated group in a small series with a minimum of 16 years follow-up [24].
  • At a minimum of 16 years follow-up, patients treated nonsurgically reported little pain, some crepitus (usually painless), and a consistent ability to return to work [24].

Operative Management

  • When nonoperative treatment fails, several surgical options exist for snapping scapula syndrome [5].
  • Most patients experience residual symptoms after arthroscopic management of snapping scapula syndrome [4].
  • For patients who fail conservative management, arthroscopic bursectomy and partial scapulectomy is a reasonable option [23].
  • Arthroscopic bursectomy and partial scapulectomy is technically demanding and requires an in-depth understanding of the complex anatomy of the scapulothoracic region [23].
  • Improvement in functional outcomes and pain relief are reliably achieved after surgical treatment of snapping scapula syndrome [28].
  • Poorer outcomes can be seen in workers' compensation patients as well as those with residual symptomatic shoulder pathology following surgical treatment [28].
  • Operative time is shorter without scapuloplasty when performing arthroscopic scapulothoracic bursectomy [30].
  • Open surgical treatment for snapping scapula provides durable pain relief [24].
  • Patients treated surgically for snapping scapula report little pain, some crepitus (usually painless), and a consistent ability to return to work at a minimum of 16 years follow-up [24].
  • At the end of 1 year, all patients in a case series of arthroscopic management for recalcitrant scapulothoracic bursitis had a constant score above 90 and were completely relieved of snapping around the scapula [11].
  • Patients in a case series of arthroscopic management for recalcitrant scapulothoracic bursitis had full pain-free movements at the shoulder and scapulothoracic joints at 1 year [11].
  • A patient with snapping scapula syndrome remained asymptomatic with full range of motion and no further complaints of pain or snapping at twenty-six months postoperatively [12].
  • Snapping and pain were completely gone and the patient was satisfied with the results at 2 years 6 months after operation for abnormal angulation of the superior angle of the scapula [13].
  • Arthroscopic access to the scapulothoracic space is simple and reproducible, with bursal tissue clearance optimizing visualization [25].
  • Arthroscopic treatment of snapping scapula follows 8 key steps to ensure a safe and effective procedure [10].
  • A technique for arthroscopic management of snapping scapula syndrome includes scapulothoracic bursectomy and superomedial partial scapulectomy, which has been refined over nearly two decades of experience [16].
  • Most authors have recommended partial scapulectomy or resection of the superomedial angle of the scapula in patients with scapular crepitus and pain caused by bony incongruity [81].
  • The decision for and timing of operative management should be individualized for each patient [81].
  • Operative options include partial scapulectomy and open versus arthroscopic bursectomy [81].

Complications

  • Arthroscopic management of snapping scapula syndrome results in most patients experiencing residual symptoms [4].
  • Snapping scapula syndrome is difficult to recognize and treat [3].

Recovery

Non-Operative

  • Nonoperative treatment for snapping scapula syndrome includes physical therapy for scapular muscle strengthening and nonsteroidal anti-inflammatory medications [29].
  • In most cases, nonoperative treatment is curative [29].

Operative Outcomes

  • Improvement in functional outcomes and pain relief are reliably achieved after surgical treatment [28].
  • Poorer outcomes can be seen in workers' compensation patients as well as those with residual symptomatic shoulder pathology [28].
  • At the end of 1 year, all the patients had a constant score above 90 and were completely relieved of snapping around the scapula having full pain-free movements at the shoulder and scapulothoracic joints [11].
  • The patient remained asymptomatic with full range of motion and no further complaints of pain or snapping at twenty-six months postoperatively [12].
  • A year after excision, the patient has not suffered recurrent pain in the left shoulder [90].

Surgical Technique and Planning

  • Operative time is shorter without scapuloplasty [30].
  • The 4D CT scan images defined pathology well in patients with snapping scapula syndrome and improved assessment of the amount and location of the scapular bone and soft tissue causing symptoms [18].

Key Evidence

  • [L5] Diagnosis and management of snapping scapula syndrome remains challenging despite recent advances. [1] (10.5435/jaaos-21-04-214)
  • [L4] Snapping scapula syndrome can be a debilitating disorder. [2] (10.1016/j.arthro.2012.05.889)
  • [L5] The snapping scapula syndrome is caused by either osseous lesions or scapulothoracic bursitis and can be difficult to recognize and treat. [3] (10.1155/2013/635628)
  • [L1] Arthroscopic management of snapping scapula syndrome yields improvement in pain, crepitus, and range of motion in a majority of patients; however, most patients experience residual symptoms. [4] (10.1007/s00167-017-4693-5)
  • [L5] Treatment of patients with snapping scapula syndrome begins with nonoperative methods; when nonoperative treatment fails, several surgical options exist. [5] (10.1177/0363546504268790)
  • [Case_report] Osteochondroma of the scapula is a rare entity that may present with snapping scapula syndrome when it alters scapulothoracic mechanics. [6] (10.1016/j.otsr.2017.01.019)
  • [L4] Snapping scapula is the clinical expression of the scapulothoracic impingement due to mechanical factors and/or muscle imbalance. [7] (10.1016/s1058-2746(96)80466-6)
  • [L4] Arthroscopic scapulothoracic treatment provides significant pain relief and functional improvement for painful snapping scapula symptoms not responding to non-surgical treatment modalities. [8] (10.2174/1874325001711010785)
  • [L5] The snapping scapula, also called “washboard syndrome” is a controversial condition attributed to bony and soft tissue abnormalities. [9] (10.11138/mltj/2013.3.2.080)
  • [L5] Arthroscopic treatment of snapping scapula follows 8 key steps to ensure a safe and effective procedure. [10] (10.1016/j.eats.2025.103671)
  • [L4] At the end of 1 year, all the patients had a constant score above 90 and were completely relieved of snapping around the scapula having full pain-free movements at the shoulder and scapulothoracic joints. [11] (10.13107/jocr.2025.v15.i02.5290)
  • [Case_report] The patient remained asymptomatic with full range of motion and no further complaints of pain or snapping at twenty-six months postoperatively. [12] (10.2106/00004623-198264060-00020)
  • [L5] At 2 years 6 months after the operation, snapping and pain were completely gone and the patient was satisfied with the results. [13] (10.1016/s1058-2746(03)00178-2)
  • [L3] Arthroscopic treatment for snapping scapula syndrome resulted in significant improvement in pain and function with high patient satisfaction at a mean follow-up of 3.4 years. [14] (10.1177/2325967116s00097)
  • [L3] Arthroscopic scapuloplasty leads to significant improvement in pain and function in patients with snapping scapula syndrome refractory to conservative treatment. [15] (10.1016/j.arthro.2020.07.024)
  • [L5] This Technical Note presents a technique for arthroscopic management of snapping scapula syndrome that includes scapulothoracic bursectomy and superomedial partial scapulectomy, which has been refined over nearly two decades of experience. [16] (10.1016/j.eats.2022.02.028)
  • [L5] The editorial commentary notes that the referenced study by Menge et al. concludes that arthroscopic surgery is an effective treatment for snapping scapula syndrome in both primary and revision cases, showing significant improvements in all postoperative outcome scores at a mean of 3.4 years. [17] (10.1016/j.arthro.2016.11.017)
  • [L5] The 4D CT scan images defined pathology well in patients with snapping scapula syndrome and improved assessment of the amount and location of the scapular bone and soft tissue causing symptoms. [18] (10.1016/j.jse.2014.09.020)
  • [L4] Arthroscopic resection of the superomedial corner of the scapula is a useful technique in patients whose pain and clicking can be clinically localized and who have failed to respond to conservative measures. [19] (10.1016/s1058-2746(99)90056-3)
  • [L5] It should be noted that rib fractures at the posterior angle could cause snapping scapula syndrome. [20] (10.1016/s1058-2746(03)00055-7)
  • [Paper] For those patients who fail conservative management, arthroscopic bursectomy and partial scapulectomy is a reasonable option, but is technically demanding and requires an in-depth understanding of the complex anatomy of the scapulothoracic region. [23] (10.1016/j.csm.2014.06.003)
  • [L3] [24] (10.1007/s11999-015-4614-1)
  • [Paper] Arthroscopic access to the scapulothoracic space is simple and reproducible, with bursal tissue clearance optimizing visualization. [25] (10.1016/j.eats.2015.07.002)
  • [L4] [26] (10.5435/00124635-199809000-00001)
  • [L4] Improvement in functional outcomes and pain relief are reliably achieved after surgical treatment, although poorer outcomes can be seen in workers' compensation patients as well as those with residual symptomatic shoulder pathology. [28] (10.1177/2325967113505739)
  • [L5] In most cases, nonoperative treatment is curative and includes physical therapy for scapular muscle strengthening and nonsteroidal anti-inflammatory medications. [29] (10.1016/j.arthro.2008.12.022)
  • [L3] Operative time is shorter without scapuloplasty. [30] (10.1016/j.jse.2023.03.020)
  • [L5] Fluoroscopy provides a realtime method of evaluating and documenting abnormal osseous mechanics of the scapulothoracic bursal region. [31] (10.1007/s11420-007-9047-2)
  • [L3] Anterior angulation of the medial scapula in the axial plane was associated with SSS. [34] (10.1016/j.jse.2014.12.034)
  • [L4] In this study, it was found that arthroscopic resection of the medial superior hook formation in combination with partial bursectomy provided good results with significant gains with respect to the WORC score in 90 % of the patients troubled by painful snapping scapula for a long time and without relief by exercise-based rehabilitation. [35] (10.1007/s00590-012-1154-1)
  • [L4] A mass composed of alternating strands of fatty and fibrous tissue is pathognomonic if it is located at the inferior pole of the scapula. [36] (10.1016/j.jbspin.2004.04.006)
  • [L4] [40] (10.1177/19417381211029211)
  • [Case_report] Scapular osteochondroma is a rarely reported cause of scapular pseudo-winging, and should be considered in the differential diagnosis when winging and a mass are present. [43] (10.1007/s11552-014-9659-1)
  • [L5] The anterior offset of the scapula appeared to be the most important bony parameter to consider during preoperative planning and the evaluation of scapulothoracic space decompression with partial scapulectomy. [46] (10.1177/0363546516687755)
  • [L3] Those patients with a concave-shaped scapula and a positive MSCA may be at risk for SSS. [47] (10.1177/2325967114s00063)
  • [L4] [48] (10.2214/ajr.181.5.1811232)
  • [L5] [81] (10.1177/1941738109338359)
  • [L5] Neurologic structures around the scapula vary significantly between the neutral arm position and the chicken-wing position commonly used in the arthroscopic treatment of SSS. [85] (10.1016/j.jse.2022.03.029)
  • [L4] Subscapular elastofibroma is a reactive pseudotumor resulting from mechanical friction of the scapula on the chest wall. [86] (10.1016/s1058-2746(05)80008-4)
  • [L5] A year after excision, the patient has not suffered recurrent pain in the left shoulder. [90] (10.1016/1058-2746(93)90078-u)

References

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[4] Arthroscopic management of snapping scapula syndrome improves pain and functional outcomes, although a high rate of residual symptoms has been reported. Knee Surgery, Sports Traumatology, Arthroscopy. 2017. DOI: 10.1007/s00167-017-4693-5

[5] Nonoperative and Operative Management of Snapping Scapula. The American Journal of Sports Medicine. 2004. DOI: 10.1177/0363546504268790

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[9] Snapping scapula syndrome: current concepts review in conservative and surgical treatment. Muscles, Ligaments and Tendons Journal. 2013. DOI: 10.11138/mltj/2013.3.2.080

[10] Full‐House Arthroscopic Treatment of Snapping Scapula Syndrome: Bursectomy, Levator Scapulae Release, and Partial Scapulectomy. Arthroscopy Techniques. 2025. DOI: 10.1016/j.eats.2025.103671

[11] Arthroscopic Management of Snapping Scapular Syndrome due to Recalcitrant Scapulothoracic Bursitis – A Case Series. Journal of Orthopaedic Case Reports. 2025. DOI: 10.13107/jocr.2025.v15.i02.5290

[12] The snapping scapula syndrome. A case report.. The Journal of Bone & Joint Surgery. 1982. DOI: 10.2106/00004623-198264060-00020

[13] Snapping scapula caused by abnormal angulation of the superior angle of the scapula. Journal of Shoulder and Elbow Surgery. 2004. DOI: 10.1016/s1058-2746(03)00178-2

[14] Two-Year Outcomes following Arthroscopic Treatment for Snapping Scapula Syndrome. Orthopaedic Journal of Sports Medicine. 2016. DOI: 10.1177/2325967116s00097

[15] Prognosis After Arthroscopic Superior Medial Scapuloplasty for Snapping Scapula Syndrome Improves After a Transient Beneficial Response With an Ultrasound‐Guided Subscapular Cortisone Injection. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2020.07.024

[16] Arthroscopic Treatment of Snapping Scapula Syndrome With Scapulothoracic Bursectomy and Partial Scapulectomy. Arthroscopy Techniques. 2022. DOI: 10.1016/j.eats.2022.02.028

[17] Editorial Commentary: Arthroscopy of the Scapulothoracic Joint for Treatment of Snapping Scapula Syndrome—Minimum 2‐Year Results in a Large Series, a Long‐Awaited Publication. Arthroscopy. 2017. DOI: 10.1016/j.arthro.2016.11.017

[18] Four-dimensional computed tomography scans facilitate preoperative planning in snapping scapula syndrome. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2014.09.020

[19] Arthroscopic partial resection of the scapula for snapping scapula: A new technique. Journal of Shoulder and Elbow Surgery. 1999. DOI: 10.1016/s1058-2746(99)90056-3

[20] Snapping scapula syndrome due to malunion of rib fractures: a case report. Journal of Shoulder and Elbow Surgery. 2004. DOI: 10.1016/s1058-2746(03)00055-7

[23] Snapping Scapula Syndrome in the Military. Clinics in Sports Medicine. 2014. DOI: 10.1016/j.csm.2014.06.003

[24] Open Surgical Treatment for Snapping Scapula Provides Durable Pain Relief, but so Does Nonsurgical Treatment. Clinical Orthopaedics & Related Research. 2016. DOI: 10.1007/s11999-015-4614-1

[25] Arthroscopic Scapulothoracic Decompression for Snapping Scapula Syndrome. Arthroscopy Techniques. 2015. DOI: 10.1016/j.eats.2015.07.002

[26] Symptomatic Scapulothoracic Crepitus and Bursitis. Journal of the American Academy of Orthopaedic Surgeons. 1998. DOI: 10.5435/00124635-199809000-00001

[28] Functional Outcomes After Arthroscopic Scapulothoracic Bursectomy and Partial Superomedial Angle Scapulectomy. Orthopaedic Journal of Sports Medicine. 2013. DOI: 10.1177/2325967113505739

[29] The Snapping Scapula: Diagnosis and Treatment. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2008.12.022

[30] Arthroscopic scapulothoracic bursectomy with and without superomedial angle scapuloplasty: a comparison of patient-reported outcomes. Journal of Shoulder and Elbow Surgery. 2023. DOI: 10.1016/j.jse.2023.03.020

[31] Imaging-Guided Treatment of Scapulothoracic Bursitis. HSS Journal®: The Musculoskeletal Journal of Hospital for Special Surgery. 2007. DOI: 10.1007/s11420-007-9047-2

[34] Association between scapula bony morphology and snapping scapula syndrome. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2014.12.034

[35] Arthroscopic treatment for snapping scapula: a prospective case series. European Journal of Orthopaedic Surgery & Traumatology. 2013. DOI: 10.1007/s00590-012-1154-1

[36] Imaging study findings in elastofibroma dorsi. Joint Bone Spine. 2004. DOI: 10.1016/j.jbspin.2004.04.006

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[42] Chapter 5 Adhesive Capsulitis, Cartilage Lesions, Nerve Compression Disorders, and Snapping Scapula. 2019.

[43] Pseudo-Winging of the Scapula Caused by Scapular Osteochondroma: Review of Literature and Case Report. HAND. 2014. DOI: 10.1007/s11552-014-9659-1

[46] A Cadaveric Model Evaluating the Influence of Bony Anatomy and the Effectiveness of Partial Scapulectomy on Decompression of the Scapulothoracic Space in Snapping Scapula Syndrome. The American Journal of Sports Medicine. 2017. DOI: 10.1177/0363546516687755

[47] Significant Association Between Snapping Scapula Syndrome and Anterior Angulation of the Superomedial Scapular Angle. Orthopaedic Journal of Sports Medicine. 2014. DOI: 10.1177/2325967114s00063

[48] Fluoroscopically Guided Scapulothoracic Injections. American Journal of Roentgenology. 2003. DOI: 10.2214/ajr.181.5.1811232

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[85] Anatomic safe zones for arthroscopic snapping scapula surgery: quantitative anatomy of the superomedial scapula and associated neurovascular structures and the effects of arm positioning on safety. Journal of Shoulder and Elbow Surgery. 2022. DOI: 10.1016/j.jse.2022.03.029

[86] Subscapular elastofibroma: A reactive pseudotumor. Journal of Shoulder and Elbow Surgery. 1996. DOI: 10.1016/s1058-2746(05)80008-4

[90] Snapping scapula: Formation of an erosive, subscapular bursal cyst after partial scapulectomy. Journal of Shoulder and Elbow Surgery. 1993. DOI: 10.1016/1058-2746(93)90078-u

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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.