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副肩峰骨

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Patient-facing topic on os acromiale — failed fusion of an acromial ossification centre that may cause shoulder pain and contribute to subacromial impingement.

Updated May 2026
一幅手绘插图，展示了肩峰骨（os acromiale）的解剖图，即肩峰伴有独立的未融合骨碎片。
肩峰骨：在骨骼成熟过程中，肩峰的前部未与肩峰的其余部分融合。 Kieran Hirpara 4.0

本页面由机器翻译，尚未经临床医生审核。英文版本为权威版本。

您的感受

您可能会感到肩部顶部疼痛。这种情况约占需要接受MRI检查的肩部问题患者的2.13%。疼痛通常源于肩袖的撕裂，肩袖是一组负责手臂活动的肌肉和肌腱。这种撕裂是由于额外的骨块异常移动并摩擦其他组织所致。

您的疼痛可能在某些活动后加剧。它也可能在夜间将您痛醒，或在尝试向患侧侧卧时引起疼痛。简单的日常任务可能会变得困难。您可能难以将手伸到背后扣上胸罩或塞好衬衫。这些动作会对骨块未完全融合的区域施加压力。

如果您曾接受过肩关节置换手术，您可能会注意到该骨块正上方有压痛。这种情况在术后患者中占1/4。好消息是，对大多数人来说，这种酸痛通常会随时间自行消退。您的外科医生将检查您的症状，以确定该额外骨块是否是引起您疼痛的主要原因。

实际发生了什么

您的肩胛骨存在一个称为肩峰骨（os acromiale）的小骨碎片，该碎片未与主骨融合。这种情况在需要接受肩部 MRI 检查的肩部疾病患者中约占 2.13%。可以将这个未融合的部位想象成肩部骨骼两部分之间松动的垫片。当手臂运动时，这个松动的碎片并非作为单一整体移动，而是会发生摩擦和移位。

这种异常运动通常会刺激附近的软组织。肩袖是由一组肌腱组成的，它们像绳索一样帮助抬起和旋转手臂。由于这块松动的骨头运动异常，可能会卡压这些肌腱。这种卡压（即撞击）通常会导致肩袖撕裂。在年轻运动员中，这种特定的损伤模式很常见，需要仔细检查以确诊。

有时，在跌倒或受伤后，这块松动的骨头可能会受伤，尽管这种情况很少见。如果您因其他原因（如反式全肩关节置换术）接受手术，1/4 的患者可能会在该部位感到局部压痛。这种疼痛通常会随时间自行消退。拥有这块额外的骨碎片似乎不会影响主要肩关节置换手术的整体效果。

我们能采取的措施

大多数人首先通过自我护理和物理治疗来管理疼痛。治疗师将指导您进行锻炼，以增强肩部肌肉并改善活动范围。这种方法旨在减少多余骨块所在部位的摩擦。在考虑其他步骤之前，您应充分尝试这一非手术方案。

如果疼痛持续存在，您的外科医生可能会讨论药物或注射治疗。抗炎药有助于减轻关节周围的肿胀和疼痛。在某些情况下，会使用皮质类固醇注射来快速缓解炎症。虽然现有证据并未明确这些治疗的具体持续时间，但许多患者在药物起效期间找到了缓解。如果您是竞技运动员，您的外科医生会仔细权衡风险，因为通常不建议职业网球运动员进行手术。

通常只有在这些保守措施无法控制您的症状时，才会考虑手术。手术的目标是移除不稳定的骨碎片，或将其固定到位以阻止引起疼痛的运动。这一决定是在与您回顾具体病例和影像学结果后，与您的外科医生共同做出的。

何时就医

若肩部持续性疼痛经休息后无改善，请咨询全科医生。若出现无力、不稳、肩部卡顿或脱位，请要求专科医生评估。若症状影响睡眠或工作，亦需引起重视。若疼痛突然加重，请及时就医。此病与肩袖损伤相关，异常运动可能导致撞击。极少数情况下，关节可在创伤后受损。若您是职业网球运动员，通常不建议手术治疗，但专科医生可通过体格检查和影像学检查明确诊断。

Reviewed by AI synthesis (v2) — pending human review · 18 May 2026.

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Evidence & references

Overview

  • In Thai patients with shoulder problems requiring MRI evaluation, the prevalence of os acromiale was 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A multicenter study aimed to determine the prevalence of and factors associated with os acromiale in the Japanese population [6].
  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Surgical options for symptomatic os acromiale include arthroscopic sub-total excision [16].
  • Surgical options for symptomatic os acromiale include arthroscopic subacromial decompression of stable fragments [16].
  • Surgical options for symptomatic os acromiale include open reduction and internal fixation of unstable fragments [16].
  • Surgical treatment is usually not indicated for os acromiale in the professional tennis player [7].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [12].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients after reverse total shoulder arthroplasty [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients after reverse total shoulder arthroplasty [3].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty [4].
  • The outcome of reverse total shoulder arthroplasty does not seem to be negatively affected by the presence of an os acromiale [9].

Anatomy & Pathophysiology

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation is 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • Awareness of the os acromiale in the young athlete is crucial to confirm diagnosis through appropriate clinical examination and image studies [11].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [13].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients after reverse total shoulder arthroplasty [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients [3].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty [4].
  • The outcome of reverse total shoulder arthroplasty does not seem to be negatively affected by the presence of an os acromiale [9].
  • Reverse shoulder arthroplasty improves range of motion, decreases pain, and increases patient satisfaction in patients with os acromiale and cuff tear arthropathy [24].
  • Surgical treatment is usually not indicated for os acromiale in the professional tennis player [7].

Classification

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation is 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [11].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [13].
  • Meta-os acromiale is the rarest subtype of os acromiale [15].

Clinical Presentation

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation was 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].
  • The outcome of reverse total shoulder arthroplasty (RTSA) does not seem to be negatively affected by the presence of an os acromiale [9].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following rTSA [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients [3].
  • Surgical treatment is usually not indicated for os acromiale in professional tennis players [7].
  • Awareness of the os acromiale, appropriate clinical examination, and image studies are crucial to confirm diagnosis in young athletes [11].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [12].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [13].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • Meta-os acromiale is the rarest subtype of os acromiale [15].
  • Liberson reviewed 1800 shoulder girdles and identified an incidence of os acromiale of 1.4% [14].
  • The lesion of os acromiale is bilateral in 62% of patients according to Liberson's review [14].

Investigations

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation is 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [11].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [13].
  • Appropriate radiographic investigation for os acromiale injury includes axillary views [13].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • Liberson reviewed 1800 shoulder girdles and identified an incidence of os acromiale of 1.4% [14].
  • The lesion of os acromiale is bilateral in 62% of patients according to Liberson's review [14].

Treatment

  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments [16].
  • Open reduction and internal fixation using cannulated screws or tension band wiring have superior outcomes in the literature in the treatment of symptomatic os acromiale [19].
  • A new arthroscopic technique of fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction [17].
  • A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation [21].
  • Special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation for meta-os acromiale, the rarest subtype of os acromiale [15].
  • Surgical treatment is usually not indicated for os acromiale in the professional tennis player [7].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [12].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients [3].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].
  • The outcome of reverse total shoulder arthroplasty (RTSA) does not seem to be negatively affected by the presence of an os acromiale [9].

Complications

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation was 2.13% [1].
  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following reverse total shoulder arthroplasty [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients [3].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty [4].
  • Reverse total shoulder arthroplasty remains a safe and effective treatment option in the presence of os acromiale [4].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Surgical treatment is usually not indicated for os acromiale in professional tennis players [7].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • The incidence of os acromiale identified by Liberson was 1.4% [14].
  • The lesion of os acromiale was bilateral in 62% of patients in Liberson's review [14].

Recovery

  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients [3].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].
  • Reverse total shoulder arthroplasty (rTSA) remains a safe and effective treatment option in patients with os acromiale [4].
  • The outcome of reverse total shoulder arthroplasty (RTSA) does not seem to be negatively affected by the presence of an os acromiale [9].
  • Surgical treatment is usually not indicated for os acromiale in professional tennis players [7].

Key Evidence

  • [L3] In Thai patients with shoulder problems who required MRI evaluation, the prevalence of os acromiale was 2.13%. [1] (10.1177/23259671221078806)
  • [L4] Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes. [2] (10.1016/j.jse.2019.05.047)
  • [L3] Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients. [3] (10.1177/2325967120965131)
  • [L4] The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after surgery and rTSA remains a safe and effective treatment option. [4] (10.1016/j.xrrt.2025.01.002)
  • [L3] The study supports previous findings that os acromiale is associated with rotator cuff injuries. [5] (10.1016/j.jseint.2025.05.015)
  • [L3] This multicenter study aimed to determine the prevalence of and factors associated with os acromiale in the Japanese population. [6] (10.1016/j.jse.2025.01.008)
  • [L4] Surgical treatment is usually not indicated for os acromiale in the professional tennis player. [7] (10.1177/2325967118773723)
  • [L4] A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site. [8] (10.2106/00004623-198466080-00029)
  • [L4] The outcome of RTSA does not seem to be negatively affected by the presence of an os acromiale. [9] (10.1016/j.jse.2017.02.012)
  • [L4] An anatomical study showed that fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting. [10] (10.2106/00004623-200003000-00010)
  • [L4] Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis. [11] (10.1016/j.jseint.2020.02.008)
  • [L4] Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. [12] (10.1186/s12891-021-04841-1)
  • [L4] This case highlights that the synchondrosis of an os acromiale can be injured following trauma, though rarely, and emphasizes the need for appropriate radiographic investigation including axillary views and a flexible surgical approach. [13] (10.1016/j.jse.2008.02.012)
  • [L4] Meta–os acromiale is the rarest subtype of os acromiale, and special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation. [15] (10.1177/03635465211028238)
  • [L5] Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments. [16] (10.5435/jaaos-d-17-00011)
  • [L4] This new arthroscopic technique of fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction. [17] (10.1016/j.jse.2011.12.011)
  • [L4] Open reduction and internal fixation using cannulated screws, or tension band wiring have superior outcomes in the literature in the treatment of symptomatic os acromiale. [19] (10.1302/2058-5241.4.180100)
  • [L4] A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation. [21] (10.1177/0363546506288305)
  • [L4] Reverse shoulder arthroplasty improved ROM, decreased pain, and increased patient satisfaction in patients with os acromiale and cuff tear arthropathy. [24] (10.5397/cise.2019.00409)

References

[1] Prevalence of Os Acromiale in Thai Patients With Shoulder Problems: A Magnetic Resonance Imaging Study. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671221078806 [2] Os acromiale: systematic review of surgical outcomes. Journal of Shoulder and Elbow Surgery. 2020. DOI: 10.1016/j.jse.2019.05.047 [3] Os Acromiale in Reverse Total Shoulder Arthroplasty: A Cohort Study. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120965131 [4] Clinical implications of reverse total shoulder arthroplasty with an os acromiale: a systematic review. JSES Reviews, Reports, and Techniques. 2025. DOI: 10.1016/j.xrrt.2025.01.002 [5] Prevalence and factors associated with os acromiale: a multicenter study. JSES International. 2025. DOI: 10.1016/j.jseint.2025.05.015 [6] The prevalence and associated factors of os acromiale: a multicenter study. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2025.01.008 [7] Os Acromiale in Professional Tennis Players. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118773723 [8] Rotator cuff tears associated with os acromiale.. The Journal of Bone & Joint Surgery. 1984. DOI: 10.2106/00004623-198466080-00029 [9] Reverse shoulder arthroplasty in patients with os acromiale. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.02.012 [10] Os Acromiale: Frequency, Anatomy, and Clinical Implications. The Journal of Bone and Joint Surgery-American Volume. 2000. DOI: 10.2106/00004623-200003000-00010 [11] The unstable os acromiale: a cause of pain in the young athlete. JSES International. 2020. DOI: 10.1016/j.jseint.2020.02.008 [12] Os acromiale may be a contraindication of the clavicle hook plate: case reports and literature review. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04841-1 [13] Fracture of an os acromiale with associated rupture of the coracoclavicular ligaments. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2008.02.012 [14] Types of os acromiale according to Liberson. 2006. [15] Rare Symptomatic Meta–Os Acromiale in an Athlete. The American Journal of Sports Medicine. 2021. DOI: 10.1177/03635465211028238 [16] Symptomatic, Unstable Os Acromiale. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00011 [17] Arthroscopically assisted internal fixation of the symptomatic unstable os acromiale with absorbable screws. Journal of Shoulder and Elbow Surgery. 2012. DOI: 10.1016/j.jse.2011.12.011 [19] Os acromiale: a review of its incidence, pathophysiology, and clinical management. EFORT Open Reviews. 2019. DOI: 10.1302/2058-5241.4.180100 [21] Surgical Stabilization of Os Acromiale in a Fast-Pitch Softball Pitcher. The American Journal of Sports Medicine. 2006. DOI: 10.1177/0363546506288305 [24] Reverse shoulder arthroplasty with os acromiale. Clinics in Shoulder and Elbow*. 2020. DOI: 10.5397/cise.2019.00409

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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.