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Hội chứng Đau Vùng Phức hợp (CRPS)

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What CRPS is, why it sometimes follows a wrist or hand injury or operation, how it is recognised and treated, and what recovery looks like.

Updated Aug 2026
Một bàn tay có quầng sáng mềm, gợi ý tăng độ nhạy cảm.
Trong CRPS, một chi có thể trở nên đau dữ dội, sưng và nhạy cảm quá mức so với tổn thương ban đầu. Kieran Hirpara 4.0

Trang này được dịch bằng máy và chưa được bác sĩ kiểm tra. Bản tiếng Anh là bản chính thức.

Những gì bạn đang cảm nhận

Bạn có thể nhận thấy cơn đau khác với cảm giác đau nhức thông thường. Cơn đau thường bắt đầu ở một bàn tay, cánh tay, bàn chân hoặc cẳng chân. Cơn đau có thể có cảm giác như bỏng rát, đập thình thịch hoặc đâm nhói. Bạn có thể cảm thấy nhạy cảm hơn với việc chạm vào hoặc thay đổi nhiệt độ. Ngay cả quần áo nhẹ hoặc một luồng gió nhẹ cũng có thể gây khó chịu. Điều này xảy ra do các dây thần kinh của bạn gửi các tín hiệu hỗn loạn lên não.

Cơn đau thường trở nên nghiêm trọng hơn vào ban đêm. Cơn đau cũng có thể bùng phát sau khi bạn đã vận động trong ngày. Khi vừa thức dậy, chi của bạn có thể cảm thấy cứng hoặc sưng. Tình trạng cứng này có thể khiến các hoạt động đơn giản trở nên khó khăn. Bạn có thể gặp khó khăn khi với tay ra sau lưng để cài móc áo bra. Việc nhét áo vào quần hoặc cài khuy áo khoác có thể cảm thấy bất tiện và gây đau. Việc nâng vật hoặc cầm nắm đồ vật có thể trở nên khó khăn.

Ngủ nghiêng về phía bị ảnh hưởng thường là không thể. Bạn có thể thấy mình phải thay đổi tư thế thường xuyên để tìm sự thoải mái. Sự khó chịu này có thể cản trở sinh hoạt hàng ngày và giấc ngủ của bạn. Trong khi điều trị sớm giúp giảm nguy cơ mất chức năng vĩnh viễn, một số người vẫn gặp phải những thay đổi kéo dài. Bác sĩ phẫu thuật của bạn sẽ làm việc cùng bạn để quản lý các triệu chứng này. Hiểu rõ những gì bạn đang cảm nhận là bước đầu tiên hướng tới việc chăm sóc tốt hơn.

Những gì thực sự đang xảy ra

CRPS là một tình trạng phức tạp trong đó các tín hiệu đau của cơ thể bạn bị mắc kẹt ở trạng thái "bật". Đây không chỉ là một vết thương đơn giản. Thay vào đó, đó là một vấn đề đa yếu tố liên quan đến dây thần kinh, hệ miễn dịch và thậm chí cả di truyền của bạn. Bác sĩ phẫu thuật của bạn chẩn đoán tình trạng này dựa trên tiền sử bệnh và khám thực thể, tìm kiếm các dấu hiệu cụ thể cho biết những gì đang xảy ra sai lệch trong các mô của bạn.

Hãy tưởng tượng dây thần kinh của bạn như những dây điện bị chập mạch. Các xét nghiệm cho thấy cách bạn cảm nhận đau bị thay đổi cơ bản so với những người không mắc tình trạng này. Não và dây thần kinh của bạn đang diễn giải sai các tín hiệu bình thường thành cơn đau dữ dội. Đây là lý do tại sao các loại thuốc giảm đau thông thường thường không đủ hiệu quả khi sử dụng đơn độc.

Bởi vì vấn đề liên quan đến nhiều hệ thống khác nhau, nên không có một giải pháp duy nhất. Việc nhận biết sớm là rất quan trọng. Nếu chúng ta phát hiện sớm, chúng ta có thể sử dụng các phương pháp điều trị tích cực để giảm nguy cơ trở thành vấn đề lâu dài. Tuy nhiên, ngay cả với việc chăm sóc kịp thời, một số bệnh nhân vẫn có thể trải qua những thay đổi vĩnh viễn về cách chi của họ hoạt động.

Các triệu chứng bạn cảm thấy—như sưng, thay đổi màu sắc hoặc nhạy cảm cực độ—là kết quả của sự nhầm lẫn thần kinh này. Cơ thể bạn đang phản ứng với một mối đe dọa được cảm nhận là không tồn tại. Đây là lý do tại sao chúng ta sử dụng các công cụ như Bảng điểm Hamilton để theo dõi không chỉ cơn đau của bạn, mà còn cả cách nó ảnh hưởng đến cuộc sống hàng ngày và sức khỏe tinh thần của bạn.

Mặc dù nguyên nhân chính xác vẫn đang được nghiên cứu, nhưng chúng ta biết rằng việc bỏ qua nó có thể dẫn đến mất chức năng vĩnh viễn. Đó là lý do tại sao chúng ta áp dụng cách tiếp cận toàn diện. Chúng ta có thể sử dụng các loại thuốc như ketamine hoặc prednisolone để làm dịu dây thần kinh. Chúng ta cũng có thể sử dụng liệu pháp laser cường độ cao để giảm đau trực tiếp tại vị trí tổn thương. Những phương pháp điều trị này nhằm mục đích phá vỡ chu kỳ đau trước khi nó trở nên vĩnh viễn.

Những điều cần biết

Bác sĩ phẫu thuật sẽ chẩn đoán tình trạng này dựa trên tiền sử bệnh và khám lâm sàng. Việc nhận biết sớm và điều trị kịp thời là rất quan trọng để giảm thiểu mất chức năng vĩnh viễn. Tuy nhiên, ngay cả khi được chăm sóc y tế, bạn vẫn có thể gặp phải tình trạng suy giảm chức năng và tàn tật vĩnh viễn. Tình trạng này có nhiều yếu tố liên quan, nghĩa là có nhiều yếu tố tham gia vào quá trình phát triển bệnh, và các nhà nghiên cứu vẫn đang nghiên cứu chính xác cách thức nó phát triển.

Nếu không được điều trị, tiên lượng là không chắc chắn. Một phương pháp tiếp cận điều trị tích cực dường như làm giảm nguy cơ phát triển dạng phổ biến nhất của hội chứng này. Đối với những người đã có các triệu chứng mạn tính hoặc khó điều trị, nên xem xét nghiêm túc việc sử dụng ketamine. Các lựa chọn khác bao gồm prednisolone, có thể được sử dụng trong các trường hợp không có sẵn các can thiệp chuyên biệt. Liệu pháp laser cường độ cao cũng cung cấp bằng chứng thuyết phục về việc giảm đau, ngay cả chỉ sau phiên trị liệu thứ ba.

Quá trình hồi phục cảm thấy khác nhau ở mỗi người. Bạn có thể nhận thấy sự thay đổi về mức độ đau trong vòng vài tuần sau khi bắt đầu các liệu pháp như điều trị bằng laser. Kiểm tra cảm giác định lượng cho thấy các cơ chế đau của bạn bị thay đổi so với nhóm đối chứng khỏe mạnh, điều này giúp giải thích tại sao các xét nghiệm tiêu chuẩn có thể không nắm bắt đầy đủ trải nghiệm của bạn. Các công cụ như Bảng câu hỏi Hamilton giúp theo dõi các triệu chứng, giới hạn chức năng và cách tình trạng này ảnh hưởng đến cuộc sống hàng ngày của bạn.

Mặc dù một số trường hợp tự khỏi, những trường hợp khác lại kéo dài. Tỷ lệ mắc hội chứng này sau phẫu thuật đơn thuần kênh khuỷu là cực kỳ hiếm, với tỷ lệ mắc trong một năm khoảng 0,33%. Đối với gãy xương cổ tay, tỷ lệ mắc được báo cáo trong vòng bốn tháng thay đổi tùy thuộc vào tiêu chuẩn chẩn đoán và cách thức quản lý gãy xương. Vì chất lượng phương pháp luận của các điều trị không dùng thuốc cho các trường hợp chi trên thường kém, bác sĩ phẫu thuật của bạn sẽ điều chỉnh kế hoạch dựa trên những gì hiệu quả với bạn. Hãy trung thực về tiến triển của bạn. Những kỳ vọng thực tế giúp bạn quản lý tình trạng này mà không có những hứa hẹn sai lầm.

Reviewed by Kieran Hirpara · 13 June 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

  • CRPS is a multifactorial condition that requires further study to better understand its pathogenesis, epidemiology, genetic involvement, psychological implications, and treatment options [3].
  • The diagnosis of CRPS is a clinical diagnosis based on history and physical examination [9].
  • Early recognition and prompt treatment of CRPS are important to minimize permanent loss of function [9].
  • Patients with CRPS may still experience permanent impairment and disability despite early recognition and prompt treatment [9].
  • The reported incidence of CRPS is influenced by the choice of diagnostic criteria, the study location, and how the fracture is managed [15].
  • A more active treatment approach seems to lower the incidence of CRPS-1 [2].
  • The incidence of CRPS following isolated cubital tunnel surgery is exceedingly rare, with an overall 1-year incidence rate of approximately 0.33% [10].
  • Quantitative sensory testing outcomes indicate altered pain mechanisms in CRPS compared to controls, with a pooled standardized mean difference of -0.41 [5].
  • The Hamilton Inventory can be relied upon to assess CRPS symptoms, functional limitations, and psychosocial impacts [4].
  • Strong consideration should be given for the use of ketamine in patients presenting with chronic or refractory CRPS [1].
  • Prednisolone has potential as a treatment option for CRPS, particularly in resource-limited settings where more specialized interventions may be unavailable [6].
  • High-intensity laser therapy (HILT) offers conclusive evidence of pain reduction in CRPS-I, even after the third treatment session [7].
  • The methodological quality of non-pharmacological treatment approaches for upper limb CRPS is overall poor [8].

Background & Causes

  • CRPS is a multifactorial condition requiring further study to understand its pathogenesis, epidemiology, genetic involvement, psychological implications, and treatment options [3].
  • Altered pain mechanisms exist in CRPS compared to controls, with a pooled standardized mean difference of -0.41 in quantitative sensory testing outcomes [5].
  • The diagnosis of CRPS is clinical, based on history and physical examination [9].
  • Early recognition and prompt treatment are important to minimize permanent loss of function, although patients may still experience permanent impairment and disability [9].
  • CRPS following isolated cubital tunnel surgery is exceedingly rare, with an overall 1-year incidence rate of approximately 0.33% [10].
  • Female sex is a significant predictor of developing CRPS following treatment of Dupuytren contracture [11].
  • Release of more than one digit is a significant predictor of developing CRPS following treatment of Dupuytren contracture [11].
  • A large percentage of patients diagnosed with and treated for CRPS type 1 can have full resolution of their symptoms with carpal tunnel release [12].
  • Elderly patients have a higher risk of developing CRPS after distal radius fracture surgery [13].
  • Females have a higher risk of developing CRPS after distal radius fracture surgery [13].
  • Manual laborers have a higher risk of developing CRPS after distal radius fracture surgery [13].
  • CRPS-related hand lesions developed in 19.4% of patients following arthroscopic rotator cuff repair [14].
  • Preexisting neuropathic disorders are the strongest predictors of CRPS after distal radius fracture [17].
  • Traumatic nerve injuries are the strongest predictors of CRPS after distal radius fracture [17].
  • Compressive neuropathies are the strongest predictors of CRPS after distal radius fracture [17].
  • Cervical radiculopathy is the strongest predictor of CRPS after distal radius fracture [17].
  • Patients with scaphoid waist fracture may be at higher risk of CRPS type I [19].
  • Women with diabetes mellitus who report severe pain before treatment are at higher risk of CRPS type I following scaphoid waist fracture [19].

Symptoms & Presentation

  • CRPS is a multifactorial condition [3].
  • Quantitative sensory testing indicates altered pain mechanisms in CRPS compared to controls, with a pooled standardized mean difference of -0.41 [5].
  • Pain is a highly debilitating symptom in CRPS-I [7].
  • The diagnosis of CRPS is based on history and physical examination [9].
  • CRPS should be considered a diagnosis of exclusion [18].
  • Glomus tumors should be included in the differential diagnosis for patients with unusual chronic pain or neuropathy [18].

Management

  • Quantitative sensory testing outcomes indicate altered pain mechanisms in complex regional pain syndrome compared to controls, with a pooled standardized mean difference of -0.41 [5].
  • Early recognition and prompt treatment of CRPS are important to minimize permanent loss of function, though patients may still experience permanent impairment and disability [9].
  • The incidence of CRPS following isolated cubital tunnel surgery (CuTS) is approximately 0.33% at 1 year [10].
  • Elderly patients have higher risks of developing CRPS after distal radius fracture surgery [13].
  • Female patients have higher risks of developing CRPS after distal radius fracture surgery [13].
  • Manual laborers have higher risks of developing CRPS after distal radius fracture surgery [13].
  • A patient with bilateral Dupuytren’s contractures who developed CRPS-1 after fasciectomy had a positive outcome with no relapse on subsequent collagenase clostridium histolyticum (CCH) injection and manipulation of the other hand [16].

Key Considerations

  • In patients with chronic or refractory CRPS, strong consideration should be given for the use of ketamine [1].
  • A more active treatment approach appears to lower the incidence of CRPS-1 [2].
  • CRPS is a multifactorial condition requiring further study to better understand its pathogenesis, epidemiology, genetic involvement, psychological implications, and treatment options [3].
  • Prednisolone is a potential treatment option for CRPS, particularly in resource-limited settings where specialized interventions may be unavailable [6].
  • High-intensity laser therapy (HILT) provides conclusive evidence of pain reduction in CRPS-I, even after the third treatment session [7].
  • CRPS diagnosis is clinical, based on history and physical examination, with early recognition and prompt treatment important to minimize permanent loss of function [9].
  • Patients with CRPS may still experience permanent impairment and disability despite early intervention [9].
  • Female sex and the release of more than one digit are significant predictors of developing CRPS following Dupuytren contracture treatment [11].
  • A large percentage of patients diagnosed with and treated for CRPS type 1 can achieve full resolution of symptoms with carpal tunnel release [12].
  • CRPS-related hand lesions developed in 19.4% of patients following arthroscopic rotator cuff repair (ARCR) [14].
  • The reported incidence of CRPS is influenced by the choice of diagnostic criteria, study location, and fracture management [15].
  • A patient with bilateral Dupuytren’s contractures developed CRPS-1 after fasciectomy but had a positive outcome with collagenase clostridium histolyticum (CCH) injection and manipulation of the other hand [16].

Key Evidence

  • [L1] In patients presenting with chronic or refractory CRPS, strong consideration should be given for the use of ketamine. [1] (10.1177/15589447221131847)
  • [L3] A more active treatment approach seems to lower the incidence of CRPS-1. [2] (10.1177/1558944719895782)
  • [L4] CRPS is a multifactorial condition that still requires further studying to better understand its pathogenesis, epidemiology, genetic involvement, psychological implications, and treatment options. [3] (10.1007/s40122-021-00279-4)
  • [L4] It can be relied upon to assess CRPS symptoms, functional limitations, and psychosocial impacts. [4] (10.1016/j.jht.2025.02.004)
  • [L1] The systematic review and meta-analysis of quantitative sensory testing outcomes indicates altered pain mechanisms in complex regional pain syndrome compared to controls, with a pooled standardized mean difference of -0.41. [5] (10.1186/s13018-022-03461-2)
  • [L4] The report emphasizes the importance of recognizing CRPS and highlights the potential of prednisolone as a treatment option, particularly in resource-limited settings where more specialized interventions may be unavailable. [6] (10.1186/s12891-024-07333-0)
  • [L1] The study results offer conclusive evidence of pain reduction, a highly debilitating symptom in CRPS-I, even after the third HILT treatment session. [7] (10.1016/j.jht.2025.02.009)
  • [L1] Methodological quality of non-pharmacological treatment approaches for upper limb CRPS is overall poor. [8] (10.1177/17589983221138610)
  • [L2] CRPS following isolated CuTS is exceedingly rare, with an overall 1-year incidence rate of approximately 0.33%. [10] (10.1016/j.jhsg.2026.101028)
  • [L3] Female sex and release of more than one digit are significant predictors of developing CRPS. [11] (10.1177/1558944720963915)
  • [L3] This study demonstrates that a large percentage of patients diagnosed with and treated for CRPS type 1 can have full resolution of their symptoms with carpal tunnel release. [12] (10.1016/j.jhsa.2024.09.024)
  • [L3] The occurrence of CRPS is the result of many factors, with elderly patients, females, and manual laborers having higher risks. [13] (10.1186/s12891-024-07948-3)
  • [L3] CRPS-related hand lesions developed in 19.4% of patients following ARCR. [14] (10.5397/cise.2021.00080)
  • [L1] The reported incidence of CRPS is influenced by choice of diagnostic criteria, along with the study location and/or how the fracture is managed. [15] (10.1177/1758998320910179)
  • [L4] The positive outcome for this woman with Dupuytren's and CRPS-I after CCH injection is encouraging. [16] (10.1016/j.jht.2024.09.002)
  • [L3] Preexisting neuropathic disorders, particularly traumatic nerve injuries, compressive neuropathies, and cervical radiculopathy, are the strongest predictors of CRPS after distal radius fracture. [17] (10.1016/j.jhsa.2026.01.004)
  • [Case_report] Glomus tumors should be included in the differential diagnosis for patients with unusual chronic pain or neuropathy, and the diagnosis of CRPS should only be a diagnosis of exclusion. [18] (10.1177/1558944719895618)
  • [L2] Patients suffering from scaphoid waist fracture may be at a higher risk of CRPS I, especially in women with diabetes mellitus who report severe pain before treatment. [19] (10.1186/s12891-021-04977-0)

References

[1] Pharmacologic Treatments in Upper Extremity Complex Regional Pain Syndrome: A Review and Analysis of Quality of Evidence. HAND. 2022. DOI: 10.1177/15589447221131847

[2] Treatment of Distal Radius Fracture: Does Early Activity Postinjury Lead to a Lower Incidence of Complex Regional Pain Syndrome?. HAND. 2020. DOI: 10.1177/1558944719895782

[3] Complex Regional Pain Syndrome: A Comprehensive Review. Pain and Therapy. 2021. DOI: 10.1007/s40122-021-00279-4

[4] Psychometric evaluation of the Hamilton Inventory to evaluate signs and symptoms in patients with Complex Regional Pain Syndrome (CRPS). Journal of Hand Therapy. 2025. DOI: 10.1016/j.jht.2025.02.004

[5] Pain mechanisms in complex regional pain syndrome: a systematic review and meta-analysis of quantitative sensory testing outcomes. Journal of Orthopaedic Surgery and Research. 2023. DOI: 10.1186/s13018-022-03461-2

[6] Complex regional pain syndrome: diagnostic challenges and favorable response to prednisolone. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07333-0

[7] Effect of high-intensity laser therapy and mirror therapy on complex regional pain syndrome type I in the hand area: A randomized controlled trial. Journal of Hand Therapy. 2025. DOI: 10.1016/j.jht.2025.02.009

[8] Person-centred management of upper limb complex regional pain syndrome: an integrative review of non-pharmacological treatment. Hand Therapy. 2023. DOI: 10.1177/17589983221138610

[9] Complex Regional Pain Syndrome. 2021.

[10] Incidence and Patient-Level Risk Factors for Complex Regional Pain Syndrome Following Cubital Tunnel Surgery. Journal of Hand Surgery Global Online. 2026. DOI: 10.1016/j.jhsg.2026.101028

[11] Separating Fact From Fiction: A Nationwide Longitudinal Examination of Complex Regional Pain Syndrome Following Treatment of Dupuytren Contracture. HAND. 2020. DOI: 10.1177/1558944720963915

[12] Outcomes of Median Nerve Release in Complex Regional Pain Syndrome Type 1 of the Hand: A Prospective Case Series. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2024.09.024

[13] Dynamic risk factors for complex regional pain syndrome after distal radius fracture surgery: multivariate analysis and prediction. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07948-3

[14] Clinical outcome in patients with hand lesions associated with complex regional pain syndrome after arthroscopic rotator cuff repair. Clinics in Shoulder and Elbow. 2021. DOI: 10.5397/cise.2021.00080

[15] What is the incidence of complex regional pain syndrome (CRPS) Type I within four months of a wrist fracture in the adult population? A systematic review. Hand Therapy. 2020. DOI: 10.1177/1758998320910179

[16] The case of a woman with bilateral Dupuytren’s contractures who developed CRPS-1 after fasciectomy with no relapse on subsequent collagenase clostridium histolyticum injection and manipulation of the other hand: Considerations for implementing a Budapest criteria checklist and assessing vasomotor instability by measuring differences in skin temperature. Journal of Hand Therapy. 2025. DOI: 10.1016/j.jht.2024.09.002

[17] A Nationwide Propensity Score-Matched Analysis Identifying Preinjury Predictors of Complex Regional Pain Syndrome Following Distal Radius Fracture. The Journal of Hand Surgery. 2026. DOI: 10.1016/j.jhsa.2026.01.004

[18] An Unusual Case of Periosteal Glomus Tumor at the Metacarpal Base Presenting as Type II CRPS: Case Report. HAND. 2020. DOI: 10.1177/1558944719895618

[19] Determinants of complex regional pain syndrome type I in patients with scaphoid waist fracture- a multicenter prospective observational study. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-021-04977-0

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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.