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桡管综合征

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Radial tunnel syndrome — causes forearm pain, weakness straightening fingers, and is distinct from tennis elbow.

Updated Aug 2026
插图显示一个人因疼痛而紧握上臂外侧前臂。
桡管综合征引起肘部下方外侧前臂的钝痛。 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

您可能会注意到肘部外侧出现深部的酸痛。这种不适感通常会沿着前臂背侧向手腕和手部放射。与其他神经问题不同，在此阶段您通常不会感到手部无力。相反，主要症状是持续性疼痛，且难以精确定位到某一具体部位。

当您对抗阻力伸展腕关节或手指时，疼痛往往会加重。在抓握物体、转动门把手或掌心向下提举物品时，您可能会感到疼痛加剧。需要重复手臂活动的活动（如打字或园艺）可能诱发疼痛发作。酸痛在夜间也可能变得更加明显，导致难以找到舒适的睡眠姿势。

随着不适感加剧，日常活动可能变得具有挑战性。简单的动作，如伸手到背后扣内衣或塞衬衫下摆，可能会引起尖锐的刺痛或钝痛。您可能会为了避免某些动作以保护手臂，这可能导致随着时间的推移出现僵硬。虽然休息通常能提供一定的缓解，但疼痛可能会持续存在并干扰您的日常生活。

如果保守措施无法缓解您的症状，我们将讨论进一步的选项。我们的方法侧重于确定刺激的来源，以指导您的康复。我们旨在通过为您量身定制的计划，帮助您恢复舒适感和功能。

实际发生了什么

桡管综合征是由于桡神经在沿手臂下行过程中受到压迫所致。该神经穿过前臂中一个狭窄的通道，称为桡管。可以将这个通道想象成一个紧身的袖套。当周围组织肿胀或收紧时，就会对神经产生压迫。这种压力会阻碍神经向肌肉发送清晰的信号。

桡神经控制着抬起手腕和手指的肌肉，并为手背提供感觉。当神经受压时，您可能会感到肘部和前臂外侧深处疼痛。当您试图在抗阻情况下伸直手腕时，这种疼痛通常会加重。您可能还会注意到握力减弱或提举物体困难。这些症状的发生是因为神经在压力下难以与肌肉进行有效沟通。

您的外科医生会寻找这种压迫发生的具体位置。没有任何一种单一的手术入路能够完全显露并松解桡管内所有潜在的压迫点。因此，仔细的检查至关重要。如果保守治疗无效，可能会建议手术以解除神经压迫。其目的是创造更多空间，使神经能够再次自由移动。

在某些情况下，该问题与其他肘部疾病有关。例如，肘关节僵硬有时源于神经刺激。如果您因肘关节僵硬接受手术，您的外科医生会检查是否存在任何神经受累情况。即使术前您的神经功能看似正常，也可能考虑进行预防性神经松解。这有助于预防未来的并发症，并确保手臂运动和力量获得最佳恢复。

我们能采取的措施

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，他所采取的方法反映了我们在诊所中对该疾病的管理方式。我们通常从非手术治疗开始。这一步骤侧重于休息和活动调整，以减轻前臂的负担。物理治疗旨在增强手臂和手腕的力量与灵活性。我们通常建议在进行其他选择之前，先充分尝试这种保守治疗。

药物治疗有助于在愈合过程中控制疼痛和炎症。您的外科医生可能会建议使用抗炎药物来减少神经周围的肿胀。在某些情况下，我们会讨论注射治疗。皮质类固醇注射可以减轻炎症，尽管效果是暂时的。透明质酸或富血小板血浆（PRP）注射是您的外科医生可能会讨论的其他选择，以支持组织健康。这些治疗旨在缓解症状并改善功能，而无需进行手术。

当非手术治疗未能提供足够的改善时，会考虑手术治疗。对于结构性或急性问题（例如骨折导致的神经损伤），在没有先进行非手术试验的情况下，我们也建议立即进行手术。手术减压涉及释放对桡神经的压力。这是针对对保守治疗无反应的病例的可行选择。在特定情况下，例如肘关节置换术中水泥导致的神经损伤，立即移除水泥并进行神经松解可能有助于恢复。对于长期存在的神经损伤且神经无法修复的情况，可能会使用肌腱转移来恢复手部功能。我们会与您讨论这些选项，以确保计划符合您的需求。

预期情况

对大多数人而言，桡管综合征无需手术即可改善。70%–88% 的桡神经损伤可自发恢复。这意味着您的症状可能会随时间自行缓解。初始非手术治疗是标准的第一步。您的外科医生将指导您进行保守治疗，以帮助神经愈合。

如果您的症状在保守治疗后没有改善，手术可能是一个选项。手术减压可解除对桡神经的压力。这通常仅保留用于在其他治疗后仍持续疼痛的病例。手术后的预后取决于多种因素，包括您出现症状的时间长短以及神经受压的具体原因。

恢复是一个渐进的过程。如果需要手术，您的外科医生将致力于减轻对神经的压力。您可能会在数周至数月内注意到感觉或力量的变化。在某些情况下，例如与骨折相关的损伤，在受伤后 3 周内进行早期手术探查可提高恢复神经功能的可能性。然而，即使进行干预，也不能保证每个人都能完全康复。

保持现实的期望非常重要。虽然许多患者会经历显著改善，但有些人可能会继续存在残留症状。治疗的目标是尽可能减轻疼痛并恢复功能。您的外科医生将根据您的具体情况以及对初始治疗的反应，与您讨论具体的预后。

如果神经损伤严重或病程较长，可能会考虑肌腱转移等额外手术。这些手术通过重新排列肌腱来帮助恢复功能。这通常被视为不可修复神经病变的最后手段。然而，大多数患者通过非手术方法或标准减压手术获得缓解。

我们将支持您度过这一过程的每一个阶段。我们将密切监测您的进展，并根据需要调整您的护理计划。我们的目标是帮助您以最小的不适感回归日常生活。如果您对接下来会发生什么有疑问，请随时提问。

何时就医

若外侧肘部或前臂持续疼痛且休息后无改善，请咨询全科医生。若发现腕部或手指无力，或症状干扰睡眠或工作，请要求专科医生评估。疼痛或麻木突然加重也需及时就诊。尽管许多桡神经损伤可在3至5个月内自行恢复，但早期评估至关重要。与等待观察相比，在受伤后3周内进行手术探查与显著更高的桡神经功能恢复率相关。非手术治疗是桡管综合征的一线治疗方法，但及时评估可确保您获得正确的治疗。

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Talk to your treating clinician for advice specific to you.

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

Evidence & references

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

Overview

  • Radial tunnel syndrome is an illness construct based on a speculative pathophysiology with no verifiable pathophysiology or accepted reference standard for diagnosis [2].
  • The traditional clinical issue surrounding radial tunnel syndrome has been properly identifying it [1].
  • Radial tunnel syndrome is distinct from posterior interosseous nerve syndrome, though both are reviewed in the context of radial nerve pathology [8].
  • The Rule-of-Nine test effectively specifies the site of tenderness for the diagnosis of radial tunnel syndrome [4].
  • Nonsurgical management is considered first-line treatment for radial tunnel syndrome [3].
  • Surgical decompression remains a viable option for refractory cases of radial tunnel syndrome despite ongoing controversy regarding diagnosis and outcomes [3].
  • There is a tendency that surgical decompression of the radial tunnel might be effective in patients with radial tunnel syndrome [14].
  • Pain in patients with radial tunnel syndrome may be treated successfully by surgical decompression of the superficial branch of the radial nerve [11].
  • Corticosteroid injection demonstrated improvement in standardized outcomes measures of pain and function at one year in 75% of patients presenting with symptoms of radial tunnel syndrome [5].
  • Surgical decompression of the median nerve or the anterior interosseous nerve (AIN) in the forearm is rarely indicated, and a prolonged nonsurgical approach is warranted in most cases [19].

Anatomy & Pathophysiology

  • It is important to understand the anatomic course and distribution of the radial nerve to make an accurate diagnosis [9].
  • The posterior interosseous nerve crosses the radial head midline and increases its distance from bony structures with supination of the forearm [26].
  • Supination increases the linear distance between the posterior interosseous nerve and the radial head, which should be considered to increase safe working volume during intra-articular procedures on the anterolateral aspect of the elbow [26].
  • The distance of the posterior interosseous nerve from the radial head appears to increase with forearm supination, potentially increasing safe working space [31].
  • Predictive accuracy for posterior interosseous nerve localization in the proximal forearm is highest when the arm is in a supinated position [32].
  • The posterior interosseous nerve moves farther from the radial head during elbow extension than flexion [35].
  • The posterior interosseous nerve moves farther from the radial head during forearm pronation than supination [35].
  • Distal migration of the posterior interosseous nerve is minimal (3.5 mm) across various elbow and forearm positions [35].
  • Wrist proprioception appears to be a multifactorial phenomenon [34].
  • There is controversy surrounding radial tunnel syndrome, dynamic compression theories, and the difficulty in differentiating it from tennis elbow [37].

Classification

  • Radial tunnel syndrome is traditionally defined as a pain syndrome caused by compression of the posterior interosseous nerve at the proximal forearm [7].
  • Radial tunnel syndrome and posterior interosseous nerve compression are distinct entities with different clinical presentations but share identical potential sites of nerve interference [12].
  • Radial tunnel syndrome and posterior interosseous nerve compression are proposed to be mild (radial tunnel syndrome) and severe (posterior interosseous nerve compression) forms of one disease to simplify nomenclature [12].
  • MR imaging features provide credence to the concept that radial tunnel syndrome is a distinct clinical entity related to compression of the posterior interosseous nerve [10].
  • The issue surrounding radial tunnel syndrome traditionally has been properly identifying it clinically [1].
  • It is important to understand the anatomic course and distribution of the radial nerve in order to make an accurate diagnosis [9].
  • Nomenclature advocates for consistent use of terminology distinguishing the deep branch of the radial nerve and the posterior interosseous nerve [17].
  • Radial tunnel syndrome and posterior interosseous nerve syndrome are recommended to be viewed as a single condition presenting along a spectrum of nerve entrapment [17].

Clinical Presentation

  • Radial tunnel syndrome is traditionally characterized by difficulty in proper clinical identification [1].
  • Radial tunnel syndrome is an illness construct based on speculative pathophysiology with no verifiable pathophysiology or accepted reference standard for diagnosis [2].
  • There is ongoing controversy regarding the diagnosis and outcomes of radial tunnel syndrome [3].
  • Radial tunnel syndrome is a pain syndrome caused by compression of the posterior interosseous nerve at the proximal forearm [7].
  • Radial tunnel syndrome and posterior interosseous nerve compression are distinct entities with different clinical presentations [12].
  • Radial tunnel syndrome and posterior interosseous nerve compression share identical potential sites of nerve interference [12].
  • Radial tunnel syndrome is a distinct clinical entity related to compression of the posterior interosseous nerve [10].
  • Understanding the anatomic course and distribution of the radial nerve is important for making an accurate diagnosis [9].
  • Radial tunnel syndrome and posterior interosseous nerve syndrome may be viewed as a single condition presenting along a spectrum of nerve entrapment [17].

Investigations

  • Radial tunnel syndrome is traditionally identified through clinical evaluation [1].
  • MR imaging provides credence to the concept that radial tunnel syndrome is a distinct clinical entity related to compression of the posterior interosseous nerve [10].
  • Dynamic ultrasonographic assessment of changes in the anteroposterior diameter and cross-sectional area is an effective diagnostic tool for identifying radial tunnel syndrome [18].
  • Neuroimaging should be considered as a complementary diagnostic method in posterior interosseous neuropathy syndrome [33].

Treatment

Non-Operative Management

  • Nonsurgical management is the first-line treatment for radial tunnel syndrome [3].
  • A prolonged nonsurgical approach is warranted in most cases of nerve compression syndromes in the forearm, such as ulnar tunnel syndrome, radial tunnel syndrome, anterior interosseous nerve syndrome, and pronator syndrome [19].
  • Nonoperative management with corticosteroid injection can be used as a therapeutic measure with potential long-term benefits in the treatment of radial tunnel syndrome [27].
  • Prospective evaluation of a single corticosteroid injection demonstrated improvement in standardized outcomes measures of pain and function at one year in 75% of patients presenting with symptoms of radial tunnel syndrome [5].

Operative Management

  • Surgery is advocated for high radial nerve entrapment neuropathy cases resistant to conservative treatment, emphasizing the importance of dissecting the entire length of the fibrous tunnel [6].
  • No single surgical approach was adequate for complete visualization and release of all compression points of the radial tunnel [13].

Complications

  • Isolated posterior interosseous nerve neurectomy (PINN) has shown excellent clinical outcomes, with few patients experiencing recurrent pain at long-term follow-up [21].

Recovery

  • Surgical decompression is a viable option for refractory cases of radial tunnel syndrome [3].
  • In a case of posterior interosseous-nerve syndrome secondary to rheumatoid synovitis with entrapment duration of more than two years, a tendon transfer was used as treatment [38].
  • Surgical excision can lead to rapid recovery of nerve sensation in cases of radial nerve compression by ganglion cysts [39].

Key Evidence

  • [L5] The issue surrounding radial tunnel syndrome traditionally has been properly identifying it clinically. [1] (10.1097/01.bth.0000231580.32406.71)
  • [L5] Radial tunnel syndrome is an illness construct based on a speculative pathophysiology with no verifiable pathophysiology or accepted reference standard for diagnosis. [2] (10.1016/j.jhsa.2010.03.020)
  • [L4] The article reviews the anatomy, diagnosis, and treatment of radial tunnel syndrome, noting that while nonsurgical management is first-line, surgical decompression remains a viable option for refractory cases despite ongoing controversy regarding diagnosis and outcomes. [3] (10.5435/jaaos-d-23-00314)
  • [L4] The Rule-of-Nine test effectively specifies the site of tenderness for the diagnosis of radial tunnel syndrome. [4] (10.1177/230949900401200115)
  • [L4] Prospective evaluation of corticosteroid injection demonstrated improvement in standardized outcomes measures of pain and function at one year in 75% of patients presenting with symptoms of radial tunnel syndrome. [5] (10.1016/j.jhsa.2017.06.095)
  • [Case_report] The authors advocate for surgery in high radial nerve entrapment neuropathy cases resistant to conservative treatment, emphasizing the importance of dissecting the entire length of the fibrous tunnel. [6] (10.1016/j.jse.2025.02.060)
  • [L5] Radial tunnel syndrome is a pain syndrome caused by compression of the posterior interosseous nerve at the proximal forearm. [7] (10.1016/j.ocl.2012.07.022)
  • [Paper] This article is a review of the history, anatomy, and clinical presentation of radial tunnel syndrome (RTS) and posterior interosseous nerve syndrome (PINS). [8] (10.1016/s0749-0712(21)00357-7)
  • [L5] It is important to understand the anatomic course and distribution of the radial nerve in order to make an accurate diagnosis. [9] (10.1007/s11420-011-9238-8)
  • [L4] The study provides credence to the somewhat disputed concept that radial tunnel syndrome is a distinct clinical entity related to compression of the posterior interosseous nerve. [10] (10.1148/radiol.2401050028)
  • [L4] This study indicates that pain in patients with radial tunnel syndrome may be treated successfully by surgical decompression of the superficial branch of the radial nerve. [11] (10.1177/1753193408099832)
  • [L5] Radial tunnel syndrome (RTS) and posterior interosseous nerve (PIN) compression are distinct entities with different clinical presentations but share identical potential sites of nerve interference; the author proposes unifying them as mild (RTS) and severe (PIN compression) forms of one disease to simplify nomenclature. [12] (10.1177/1753193420953990)
  • [L5] No single approach was adequate for complete visualization and release of all compression points of the radial tunnel. [13] (10.1016/j.jhsa.2015.03.009)
  • [L4] There is a tendency that surgical decompression of the radial tunnel might be effective in patients with RTS. [14] (10.1016/j.jhsa.2007.10.001)
  • [L5] The authors advocate for consistent use of the terminology distinguishing the deep branch of the radial nerve (DBRN) and the posterior interosseous nerve (PIN), and recommend viewing radial tunnel syndrome and posterior interosseous nerve syndrome as a single condition presenting along a spectrum of nerve entrapment. [17] (10.1177/17531934241254706)
  • [L4] Dynamic ultrasonographic assessment of changes in the AP diameter and CSA is an effective diagnostic tool for identifying radial tunnel syndrome. [18] (10.1177/17531934261443138)
  • [L5] Surgical decompression of the median nerve or the AIN in the forearm is rarely indicated; a prolonged nonsurgical approach is warranted in most cases. [19] (10.5435/jaaos-d-16-00010)
  • [L4] Isolated PINN have shown excellent clinical outcomes, with few patients experiencing recurrent pain at long-term follow-up. [21] (10.1177/1558944717692093)
  • [L5] Supination increases the linear distance between the PIN and radial head and should be considered to increase the safe working volume whenever intra-articular procedures are performed on the anterolateral aspect of the elbow. [26] (10.1016/j.jse.2018.08.019)
  • [L4] Nonoperative management with corticosteroid injection can be used as a therapeutic measure with potential long-term benefits in the treatment of RTS. [27] (10.1177/1558944718787282)
  • [L5] Furthermore, its distance from the radial head appears to increase with forearm supination, which could increase the safe working space. [31] (10.1055/s-0037-1605388)
  • [L5] Predictive accuracy was highest when the arm was in a supinated position. [32] (10.1016/j.arthro.2013.03.056)
  • [L4] Neuroimaging should be considered as a complementary diagnostic method in PINS. [33] (10.1212/wnl.0000000000003287)
  • [L1] Wrist proprioception appears to be a multifactorial phenomenon. [34] (10.1016/j.jht.2015.03.003)
  • [L3] The posterior interosseous nerve moved farther from the radial head during elbow extension than flexion and during forearm pronation than supination, but distal migration was minimal (3.5 mm). [35] (10.5397/cise.2024.00213)
  • [L5] The paper is a letter to the editor discussing the controversy surrounding radial tunnel syndrome, dynamic compression theories, and the difficulty in differentiating it from tennis elbow, noting that a combined operative procedure for both conditions will be reported in the future. [37] (10.2106/00004623-199274020-00024)
  • [L4] In the third patient, in whom the duration of entrapment was more than two years, a tendon transfer was used as treatment. [38] (10.2106/00004623-197355040-00009)
  • [L4] Surgical excision can lead to rapid recovery of nerve sensation in cases of radial nerve compression by ganglion cysts. [39] (10.1007/s11552-007-9083-x)

References

[1] A Unified Approach to Radial Tunnel Syndrome and Lateral Tendinosis. Techniques in Hand & Upper Extremity Surgery. 2006. DOI: 10.1097/01.bth.0000231580.32406.71

[2] Radial Tunnel Syndrome. The Journal of Hand Surgery. 2010. DOI: 10.1016/j.jhsa.2010.03.020

[3] Radial Tunnel Syndrome: Review and Best Evidence. Journal of the American Academy of Orthopaedic Surgeons. 2023. DOI: 10.5435/jaaos-d-23-00314

[4] A New Clinical Test for Radial Tunnel Syndrome—The Rule-of-Nine Test: A Cadaveric Study. Journal of Orthopaedic Surgery. 2001. DOI: 10.1177/230949900401200115

[5] Prospective Evaluation of Single Corticosteroid Injection in Radial Tunnel Syndrome. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.06.095

[6] High radial nerve entrapment neuropathy: an anatomical cadaver study and case report. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2025.02.060

[7] Radial Tunnel Syndrome. Orthopedic Clinics of North America. 2012. DOI: 10.1016/j.ocl.2012.07.022

[8] RADIAL TUNNEL SYNDROME. Hand Clinics. 1996. DOI: 10.1016/s0749-0712(21)00357-7

[9] Posterior Interosseous Neuropathy: Electrodiagnostic Evaluation. HSS Journal®: The Musculoskeletal Journal of Hospital for Special Surgery. 2012. DOI: 10.1007/s11420-011-9238-8

[10] MR Imaging Features of Radial Tunnel Syndrome: Initial Experience. Radiology. 2006. DOI: 10.1148/radiol.2401050028

[11] Radial Tunnel Syndrome: Emphasis on the Superficial Branch of the Radial Nerve. Journal of Hand Surgery (European Volume). 2009. DOI: 10.1177/1753193408099832

[12] Radial tunnel syndrome: definition, distinction and treatments. Journal of Hand Surgery (European Volume). 2020. DOI: 10.1177/1753193420953990

[13] Anatomical Study of the Surgical Approaches to the Radial Tunnel. The Journal of Hand Surgery. 2015. DOI: 10.1016/j.jhsa.2015.03.009

[14] Interventions for Treating the Radial Tunnel Syndrome: A Systematic Review of Observational Studies. The Journal of Hand Surgery. 2008. DOI: 10.1016/j.jhsa.2007.10.001

[17] Nomenclature of the radial nerve: distinguishing between the deep branch of the radial nerve and the posterior interosseous nerve. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241254706

[18] Role of high-resolution dynamic ultrasonography in the evaluation of posterior interosseous nerve compression at radial tunnel: a prospective case-control study. Journal of Hand Surgery (European Volume). 2026. DOI: 10.1177/17531934261443138

[19] Ulnar Tunnel Syndrome, Radial Tunnel Syndrome, Anterior Interosseous Nerve Syndrome, and Pronator Syndrome. Journal of the American Academy of Orthopaedic Surgeons. 2017. DOI: 10.5435/jaaos-d-16-00010

[21] Outcomes Following Isolated Posterior Interosseous Nerve Neurectomy: A Systematic Review. HAND. 2017. DOI: 10.1177/1558944717692093

[26] The posterior interosseous nerve crosses the radial head midline and increases its distance from bony structures with supination of the forearm. Journal of Shoulder and Elbow Surgery. 2019. DOI: 10.1016/j.jse.2018.08.019

[27] Prospective Evaluation of a Single Corticosteroid Injection in Radial Tunnel Syndrome. HAND. 2018. DOI: 10.1177/1558944718787282

[31] Distance of the Posterior Interosseous Nerve from the Radial Head during Elbow Arthroscopy: An Anatomical Study. Joints. 2017. DOI: 10.1055/s-0037-1605388

[32] Posterior Interosseous Nerve Localization in the Proximal Forearm: A Cadaveric Study Establishing a Non‐invasive, Patient‐normalized Parameter (SS‐49). Arthroscopy. 2013. DOI: 10.1016/j.arthro.2013.03.056

[33] Posterior interosseous neuropathy. Neurology. 2016. DOI: 10.1212/wnl.0000000000003287

[34] Multiplanar wrist joint proprioception: The effect of anesthetic blockade of the posterior interosseous nerve or skin envelope surrounding the joint. Journal of Hand Therapy. 2015. DOI: 10.1016/j.jht.2015.03.003

[35] In vivo dynamic migration of the posterior interosseous nerve across various elbow and forearm positions. Clinics in Shoulder and Elbow. 2024. DOI: 10.5397/cise.2024.00213

[37] Radial tunnel syndrome. An investigation of compression neuropathy as a possible cause.. The Journal of Bone & Joint Surgery. 1992. DOI: 10.2106/00004623-199274020-00024

[38] Posterior Interosseous-Nerve Syndrome Secondary to Rheumatoid Synovitis. The Journal of Bone & Joint Surgery. 1973. DOI: 10.2106/00004623-197355040-00009

[39] Compression Neuropathy of the Radial Nerve Due to Ganglion Cysts. HAND. 2008. DOI: 10.1007/s11552-007-9083-x

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Using Creative Commons Public Licenses

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Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees

Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

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.