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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 Aug 2026
一幅手绘插图，展示的是肩峰骨（os acromiale）的解剖图，即肩峰带有独立的未融合骨碎片。
Os acromiale：肩峰的前部在骨骼成熟过程中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

您可能会感到肩部上方疼痛。该区域位于主要盂肱关节的正上方。这种不适感通常表现为深部酸痛。在某些手臂动作下，也可能感到尖锐疼痛。许多人描述在该部位有不稳定感或弹响。这是因为小的骨碎片未能与肩胛骨其余部分完全连接。

您的症状通常在过头活动时加重。伸手去拿高处的架子或将物体举过头顶可诱发疼痛。当您向后伸手时（例如扣内衣或塞衬衫下摆），也可能感到不适。这些动作会挤压骨碎片与肩胛骨其余部分连接的区域。如果您伴有肩袖撕裂（这种情况在此病症中很常见），疼痛可能会更加剧烈。连接处的异常运动可刺激周围组织，导致炎症和进一步的不适。

夜间疼痛是另一个常见的主诉。您可能会发现难以患侧卧位睡眠。仰卧时肩部承受的压力会加重炎症区域。有些人早晨醒来时肩部僵硬。随着白天活动，疼痛可能会缓解，但在长时间活动后通常会再次出现。如果您是职业网球运动员，您的外科医生可能会建议避免手术，因为休息和康复治疗通常有助于控制症状。然而，如果保守治疗无效，可能会考虑手术选项，如切除部分骨碎片或将其固定原位，以减轻疼痛并改善功能。

实际发生了什么

您的肩关节是一个复杂的球窝关节。肩峰是肩胛骨顶部的骨性拱形结构。在大多数人的儿童期，这块骨头会融合成单一的整体。在某些情况下，一小块称为肩峰骨（os acromiale）的独立骨碎片未能融合。这种情况在接受肩部 MRI 检查的肩部问题患者中约占 2.13%。

可以将这个未融合的碎片想象成鞋里的一块松动石子。它位于本应成为主骨一部分的位置，但其活动度略大于正常范围。这种额外的运动可能会刺激周围的组织。软骨结合部（synchondrosis）是碎片与主骨之间的纤维连接。虽然这种连接通常很稳定，但偶尔也会因创伤而受损。

这种异常运动通常会导致继发性问题：撞击综合征。当骨骼或组织在狭窄的空间内相互摩擦时，就会发生撞击。当您活动手臂时，松动的碎片可能会夹住其下方的软组织。这种夹压是肩部疼痛和炎症的常见原因。

肩袖是一组稳定肩关节的肌腱。这些肌腱就像绳索一样，将上臂骨的球部固定在窝内。由于肩峰骨直接位于这些肌腱上方，异常运动可能会磨损这些肌腱。研究表明，肩峰骨常与肩袖损伤相关。松动碎片造成的夹压可能导致这些关键肌腱纤维撕裂。

如果您患有此症，在将手臂举过头顶时可能会感到疼痛。不适感源于肩关节上方拥挤空间内的摩擦和压力。理解这一机械性问题有助于解释为何简单的休息有时不足以解决问题。移动骨碎片引起的物理刺激通常需要针对性治疗才能缓解症状。

我们能做什么

基兰·希尔帕拉（Kieran Hirpara）医生是麦特私人医院（Mater Private Hospital Rockhampton）的上肢外科医生，他所采用的方法反映了我们在诊所中对此病情的管理方式。患者通过全科医生或物理治疗师的转诊来到我们这里就诊。我们首先进行全面的评估，包括病史采集、体格检查，并在必要时进行影像学检查，以确诊。对于长期存在或退行性的问题，我们通常首先采取非手术治疗。这包括调整您的活动、物理治疗或手部治疗、夹板固定以及注射治疗。只有当这些措施未能提供足够的改善时，我们才会考虑手术。对于急性结构性问题，可能会立即建议手术。

您可以从调整日常活动开始，避免引起疼痛的动作。物理治疗旨在增强您肩部周围的肌肉，以减少对肩峰骨（os acromiale）的牵拉。这是您肩胛骨上的一个额外骨碎片，可能会引起刺激。我们通常建议您先充分尝试这种保守治疗方法，然后再考虑其他选项。如果疼痛持续存在，我们可能会讨论药物治疗。这包括使用止痛药和非甾体抗炎药来帮助控制症状。可能会提供注射治疗，如皮质类固醇注射，以减少炎症并提供临时缓解。这些治疗有助于管理不适，但不会改变潜在的骨骼结构。

当保守治疗达到极限且您的症状仍然显著时，才会考虑手术。我们将此作为共同决策进行讨论，权衡潜在益处与风险。目标是当非手术方法不再有效时，缓解疼痛并恢复功能。我们的团队将根据您的具体需求和评估结果，指导您进行下一步。

预期情况

肩峰骨（Os acromiale）是肩胛骨上的一个额外骨碎片。它影响约 1/50 的患有肩部问题的患者。您可能出现双侧疼痛，因为 62% 的病例为双侧。该碎片可能会与其他骨骼摩擦，导致刺激或肩袖撕裂。

如果您有症状，您的外科医生可能会首先采取非手术治疗。这包括休息和抗炎药物。对于大多数人来说，这种方法有助于控制疼痛。如果这些措施无效，可能会考虑手术切除或修复该碎片。这通常会导致症状减轻和肩部功能改善。

术后恢复涉及手术部位局部压痛的时期。四分之一的患者会出现这种情况。好消息是，大多数患者的压痛会随时间自行消退。随着该区域愈合，您应预期逐渐恢复正常活动。

如果您接受了反式肩关节置换术，肩峰骨的存在不会对您的预后产生负面影响。该手术对您来说仍然是一个安全有效的选择。您的外科医生将确保尽管存在额外的骨碎片，关节置换仍能良好运作。

对于职业网球运动员，通常不建议手术。这项运动的需求可能超过修复该碎片的好处。在这些情况下，非手术管理症状通常是首选方案。

总体而言，需要治疗的人预后良好。大多数人会发现疼痛缓解和活动改善。您的外科医生将指导您选择最适合您具体情况的最佳方案。您应预期在数周至数月内肩部舒适度稳步改善。

何时就诊

若肩部疼痛持续且休息后无改善，请咨询全科医生。若出现无力、不稳或卡锁感、打软腿感，请要求专科评估。干扰睡眠或工作的症状也需引起重视。疼痛突然加重时应尽快评估。

肩峰骨（Os acromiale）是肩部的额外骨碎片。它约占肩部问题患者的2%。它常与肩袖损伤相关，即肩部肌肉撕裂。这些撕裂可能由于额外骨骼导致异常运动和刺激所致。早期评估有助于明确诊断并指导治疗方案。

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Want the clinical detail? Read the clinician version.

Talk to your treating clinician for advice specific to you.

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

Evidence & references

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

Overview

  • 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].
  • 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 resolves spontaneously over time in the majority of patients [3].
  • Reverse shoulder arthroplasty improves range of motion, decreases pain, and increases patient satisfaction in patients with os acromiale and cuff tear arthropathy [24].

Classification

  • Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [11].
  • 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].
  • 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].
  • 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].
  • 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

  • Appropriate radiographic investigation for os acromiale injury includes axillary views [13].

Treatment

  • 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].
  • 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].

Complications

  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following reverse total shoulder arthroplasty [3].
  • Reverse total shoulder arthroplasty remains a safe and effective treatment option in the presence of os acromiale [4].
  • 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

  • Reverse total shoulder arthroplasty (rTSA) remains a safe and effective treatment option in patients with os acromiale [4].

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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a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

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.