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Lesão do canto posterolateral

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Updated Sep 2026
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Esta página foi traduzida automaticamente e ainda não foi verificada por um médico. A versão em inglês é a versão oficial.

O que você está sentindo

O canto posterolateral é um pequeno conjunto de ligamentos e tendões localizado na parte externa e posterior do seu joelho. Quando essas estruturas sofrem lesão, a dor geralmente aparece na lateral ou na parte de trás do joelho. O joelho pode parecer instável, como se fosse ceder ao girar ou mudar de direção.

Essa lesão costuma ocorrer junto com danos a outros ligamentos do mesmo joelho, especialmente os ligamentos cruzados localizados no interior da articulação. Esse é um dos motivos pelos quais, inicialmente, pode ser difícil identificar a lesão: os sinais de várias lesões se sobrepõem, e o canto externo pode passar despercebido enquanto a atenção se concentra na lesão mais evidente. Caminhar em encostas ou escadas, girar o corpo para alcançar algo ou ficar em pé sobre uma perna podem parecer tarefas incertas. Você pode notar que o joelho fica frouxo ou gira para fora ao suportar peso.

O desconforto tende a piorar após a atividade, quando o joelho foi submetido a carga ou torção. O inchaço e a rigidez podem dificultar a flexão completa do joelho, transformando tarefas simples como agachar-se até uma prateleira baixa, ajoelhar-se no jardim ou entrar no carro em ações delicadas. Caminhadas longas ou ficar em pé por um bom tempo podem deixar a região lateral do joelho dolorida.

Se a lesão resultou de um evento de alta energia, como uma queda, colisão ou torção brusca, o joelho inteiro pode ter dado a impressão de “sair do lugar”. Nesses casos, as estruturas do canto posterolateral geralmente se rompem junto com outros ligamentos, deixando o joelho instável de forma geral, e não apenas dolorido em um único ponto.

Como esse canto é facilmente negligenciado na avaliação inicial, vale a pena descrever ao seu cirurgião quais movimentos parecem inseguros e onde exatamente está a dor. Essas informações ajudam a formar um quadro claro do que foi lesado e do que precisa ser tratado.

O que está realmente acontecendo

O canto posterolateral é um pequeno conjunto de ligamentos e tendões na borda posterior externa do joelho. Pense nele como um conjunto de amarras que fixam o lado externo da articulação, impedindo que ela se abra para fora ou gire em excesso. O principal ligamento desse grupo vai da extremidade do fêmur até a parte superior do osso menor na lateral da perna. Sua função é manter o joelho estável quando a carga é aplicada no lado externo, além de limitar a rotação que gira a perna para fora.

Quando esse canto sofre lesão, essas “amarras” afrouxam ou se rompem. O joelho então pode deslizar ou girar de maneiras para as quais não foi projetado, resultando na instabilidade e na rotação externa que você talvez tenha notado. Como esse canto também ajuda a controlar a rotação durante a flexão do joelho, ladeiras, escadas e movimentos de pivô tornam-se incertos e pouco confiáveis.

Essa lesão raramente ocorre isoladamente; geralmente acontece ao mesmo tempo que algum dano nos ligamentos cruzados localizados no interior da articulação. Nesses casos, os dois problemas se agravam mutuamente: um ligamento cruzado reconstruído pode ficar sobrecarregado e falhar se o canto posterolateral permanecer instável. É por isso que não identificar essa lesão na avaliação inicial é problemático, e por que seu cirurgião irá examiná-la com cuidado.

A lesão costuma ser classificada em graus. Um grau leve indica que os ligamentos estão esticados, mas ainda mantêm a articulação estável. Um grau grave, às vezes chamado de ruptura completa, significa que as estruturas do canto posterolateral estão totalmente rompidas e o joelho fica claramente instável. Os graus graves, especialmente quando outros ligamentos também estão lesionados, são os que geralmente exigem cirurgia.

Mais uma informação importante: um nervo responsável pela sensibilidade e movimento da perna passa bem próximo a esse canto, ao redor da parte superior do osso lateral. Esse é um dos motivos pelos quais essa lesão, bem como qualquer cirurgia nela, requer um planejamento cuidadoso.

O que podemos fazer a respeito

O exame cuidadoso dos ligamentos, aliado à ressonância magnética, é o método padrão para determinar quais estruturas foram lesadas. Mesmo assim, essa região do joelho é facilmente ignorada nos exames de imagem; por isso, caso haja alguma dúvida, verificamos diretamente durante a artroscopia.

Nas lesões mais leves, em que os ligamentos estão apenas esticados e não completamente rompidos, geralmente iniciamos o tratamento não cirúrgico. Isso envolve modificar a forma como você carrega o peso no joelho, além de um programa de fisioterapia voltado para fortalecer a região do quadril e da coxa, além de retreinar o equilíbrio e o controle necessários para manter o joelho estável em encostas, escadas e movimentos de rotação. Damos tempo suficiente para esse tratamento antes de considerar outras opções.

Nas lesões em que as estruturas dessa região estão completamente rompidas, especialmente quando outros ligamentos do mesmo joelho também foram lesados, geralmente recomendamos a cirurgia sem demora. A operação reconstrói os ligamentos danificados na parte posterior externa do joelho; quando o ligamento cruzado também está rompido, ambos são reconstruídos numa única intervenção. Nesses casos recentes, a reconstrução costuma ser mais eficaz do que a simples sutura. Mesmo quando a lesão já existe há bastante tempo e o joelho ficou progressivamente instável, a cirurgia ainda pode ser útil: ao realinhar a perna e reconstruir os ligamentos, conseguimos restaurar estabilidade suficiente para atividades cotidianas e esportes de baixa intensidade. Como essa região fica próxima a um nervo responsável pela sensibilidade e movimento da perna, planejamos a cirurgia com todo o cuidado para respeitar essa área.

Se recomendamos a cirurgia imediata ou após um período de fisioterapia depende de quais estruturas estão lesadas, do grau de instabilidade do joelho e do que você precisa que ele consiga fazer. Conversaremos sobre todas as opções e decidiremos em conjunto.

O que esperar

O prognóstico depende da gravidade do rompimento nessa região e de se outros ligamentos também foram afetados. Um estiramento leve, em que os ligamentos ainda mantêm a estabilidade, geralmente melhora com fisioterapia e com mudanças na forma como o joelho é utilizado. Já um rompimento completo, especialmente aquele decorrente de uma queda, colisão ou torção brusca, normalmente não se resolve sozinho. Se deixado sem tratamento, a instabilidade tende a persistir, podendo, com o tempo, danificar a cartilagem articular.

O momento do tratamento é fundamental. Quando a cirurgia nessa região é adiada por mais de 4 semanas após a lesão, os resultados tornam-se menos previsíveis do que quando realizada precocemente. O mesmo ocorre no joelho como um todo: quanto maior o intervalo entre a lesão e a reconstrução dos ligamentos, maior a probabilidade de as superfícies articulares terem sido danificadas. Por isso, seu cirurgião desejará obter um diagnóstico preciso o quanto antes, em vez de aguardar para ver como a situação evolui.

Quando essa região é reconstruída juntamente com quaisquer ligamentos cruzados rompidos, a maioria dos pacientes recupera a estabilidade. Em um grupo de pacientes submetidos a essa reconstrução conjunta, 80% relataram bons resultados e um joelho que se mantinha estável nas atividades diárias. A rotação externa – o movimento que gira a perna para fora – é restaurada na maioria dos pacientes. A estabilidade contra a abertura do joelho para fora também é restaurada na maioria dos joelhos, porém não em todos. Os resultados tendem a ser melhores quando os ligamentos são reconstruídos logo após a lesão, e não anos depois; além disso, pessoas que já passaram por cirurgia nos ligamentos do joelho costumam relatar qualidade de vida inferior àquelas que nunca foram operadas.

Seja realista quanto ao trabalho e às atividades físicas. Em um grupo de pacientes com múltiplos rompimentos ligamentares, 10% no total precisaram mudar de emprego por causa do joelho; entre trabalhadores braçais, esse percentual subiu para 25%. Muitas pessoas retornam às atividades cotidianas e a esportes de baixa intensidade, mas um joelho que passou por várias reconstruções ligamentares pode não ser exatamente igual ao que era antes da lesão. Seu cirurgião explicará quais são as expectativas realistas de recuperação para o seu joelho, seu trabalho e as atividades que você deseja retomar.

Quando procurar ajuda médica

Procure prontamente o seu clínico geral após qualquer lesão no joelho em que o joelho tenha parecido “sair do lugar”, ou quando a parte posterior externa do joelho esteja dolorida e o joelho pareça instável ou “ceder” durante os movimentos. Essa região do joelho é fácil de ser negligenciada, e os exames de imagem nem sempre conseguem detectá-la; por isso, vale a pena fazer uma avaliação precoce em vez de esperar. Solicite uma avaliação por um especialista se, após algumas semanas, o seu joelho ainda parecer instável ao subir/descer ladeiras, escadas ou ao fazer movimentos de rotação; ou se uma reconstrução prévia do ligamento cruzado começou a parecer instável. O momento da intervenção é crucial: a cirurgia nessa região tem melhores resultados quando realizada nas primeiras 4 semanas após a lesão; caso contrário, os resultados tornam-se menos previsíveis.

Reviewed by AI synthesis (v2) — pending human review · 9 September 2026.

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Evidence & references

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

Anatomy & Pathophysiology

Bony Anatomy

  • The bones of the knee are the distal femur, the proximal tibia, and the patella [1].
  • The medial femoral condyle is larger and projects farther posteriorly and distally than the lateral condyle [6].
  • The lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction than the medial femoral condyle [6].
  • The sulcus terminalis is a small ridge on the lateral femoral condyle just distal to the intercondylar notch that separates the patellofemoral and tibiofemoral articular surfaces [6].
  • The tibial articular surface slopes 7° to 10° in the sagittal plane [6].
  • The medial tibial plateau is larger than the lateral plateau and is concave in its frontal and sagittal planes [6].
  • The lateral tibial plateau is smaller and more circular than the medial plateau, concave in the frontal plane and convex in the sagittal plane [6].
  • The proximal fibula articulates with a facet of the lateral cortex of the tibia and is not part of the knee articulation [6].
  • The Gerdy’s tubercle is the insertion site of the iliotibial band and is located 2 to 3 cm lateral to the tibial tubercle on the proximal tibia [6].
  • The fibular head is located a mean of 1.5 cm distal to the joint line, with a range of 6 to 32 mm [18].

Ligaments

  • The lateral collateral ligament (LCL) runs from the lateral femoral condyle to the head of the fibula and is the main stabilizer against varus stress [1].
  • The LCL is part of the posterolateral “complex” or “corner” of the knee that also resists external rotation [1].
  • The popliteofibular ligament is present in 90% of knees and runs from the tendon of the popliteus muscle to the styloid on the posterior fibular head [1].
  • The LCL resists varus tibial translation as its primary function and tibial external rotation, especially at 30 degrees of knee flexion, as its secondary function [7].
  • The popliteus tendon resists tibial external rotation, especially in knee flexion, as its primary function and varus tibial translation as its secondary function [7].
  • The popliteofibular ligament resists tibial external rotation, especially in knee flexion, as its primary function and posterior tibial displacement as its secondary function [7].
  • The oblique popliteal ligament resists knee hyperextension as its primary function and varus tibial translation as its secondary function [7].
  • The posterolateral corner (PLC) is made up of the FCL, the iliotibial band, the popliteofibular ligament, the biceps femoris, and the popliteus tendon [24].
  • The PLC resists posterior translation, external rotation, and varus angulation of the tibia [24].
  • The popliteus tendon originates on the posterocentral tibia and inserts anterior and distal to the LCL on the lateral femoral epicondyle [18].
  • The popliteus tendon has an intra-articular course through the popliteal hiatus [18].

Menisci

  • The menisci are C-shaped fibrocartilaginous disks that provide shock absorption, increase congruency between joint surfaces, enhance joint stability, and aid in distribution of synovial fluid [1].
  • The medial meniscus is firmly attached to the joint capsule along its entire peripheral edge [1].
  • The lateral meniscus is attached to the anterior and posterior capsule, but there is a region posterolaterally where it is not firmly attached [1].
  • The lateral meniscus is larger than the medial meniscus and carries a greater share of the lateral compartment pressure than the medial meniscus carries for the medial compartment [1].
  • The lateral meniscus has a more circular C-shape with symmetric sizes of the anterior and posterior horns [15].
  • The popliteomeniscal fascicles extend from the lateral meniscus to the posterior capsule to create the popliteal hiatus [15].
  • The less continuous attachment of the lateral meniscus to the capsule allows for greater meniscal mobility [15].
  • Mean lateral meniscus excursion from knee extension to flexion is 11.2 mm, compared to a mean medial meniscus excursion of 5.1 mm [15].
  • The lateral meniscus covers a larger proportion of the tibial plateau than the medial meniscus [18].
  • The lateral meniscus has a mobility of 10 mm, while the medial meniscus has a mobility of 5 mm [18].

Vascular and Nerve Anatomy

  • The blood supply to the knee is formed from an anastomosis around the knee derived from the descending geniculate artery, medial and lateral superior geniculate arteries, medial and lateral inferior geniculate arteries, middle geniculate artery, and anterior tibial recurrent arteries [6].
  • The inferior geniculate arteries pass deep to their respective collateral ligaments [6].
  • The knee is innervated by branches of the femoral nerve (L2, L3, L4), obturator nerve (L2, L3, L4), and sciatic nerve (L4, L5, S1, S2) [6].
  • The largest nerve providing innervation of the intra-articular knee is the posterior articular branch of the tibial nerve [6].
  • The popliteus artery travels through the adductor hiatus, where it is relatively immobile, and distally through the fibrous arch deep to the soleus muscle [24].
  • The common peroneal nerve travels along the posterior edge of the biceps femoris and continues distally around the fibular neck [24].
  • The tibial nerve courses distally through the center of the popliteus fossa after branching from the sciatic nerve [24].

Pathophysiology and Biomechanics

  • If the menisci are not present, the convex femoral condyles articulate with the relatively flat tibial plateaus, decreasing surface area of contact and increasing pressure on the articular cartilage [1].
  • The medial meniscus has less mobility than the lateral meniscus and is more susceptible to tearing when trapped between the femoral condyle and tibial plateau [1].
  • Biomechanical studies show a significantly higher graft force during varus loading at 0 and 30 degrees of knee flexion after transection of the LCL than with intact posterolateral structures [5].
  • In knees with grade III posterolateral injuries and evidence of varus or coupled posterior-external rotation instability, repair or reconstruction of the posterolateral structures should be performed at the time of PCL reconstruction to decrease the chance of later graft failure [5].
  • The menisci bear one-third to one-half body weight and help with load transmission [19].
  • Removal of the menisci increases contact stresses, with up to four times the load transfer to bone [19].

Investigations

Physical Examination

  • A thorough knee examination should be performed to evaluate for coexisting knee pathology in patients with LCL and/or posterolateral corner injury [31].
  • A careful neurovascular examination should be performed because the incidence of neurovascular injury, particularly peroneal nerve injury, has been reported in 12–29% of posterolateral knee injuries [31].
  • The integrity of the LCL is assessed by placing a varus stress with the knee in full extension and 30 degrees of flexion [31].
  • Baseline varus opening is widely variable and should be compared to the contralateral leg [31].
  • The average baseline for varus opening is 7 degrees [31].
  • Exam findings with an isolated LCL injury include varus laxity at 30 degrees of flexion and no instability in full extension [31].
  • A significant posterolateral knee injury can be present without significant varus laxity [31].
  • The dial test is the most useful test to evaluate for posterolateral instability [31].
  • The dial test is performed by externally rotating each tibia and noting the angle subtended between the thigh and the foot at 30 and 90 degrees of flexion [31].
  • A significant difference in the dial test is an angle 5 degrees or greater than the contralateral leg [31].
  • Greater external rotation at 30 degrees on the dial test confirms injury to the posterolateral capsule alone [31].
  • Greater external rotation at 90 degrees on the dial test confirms an isolated PCL injury [31].
  • Greater rotation at both 30 and 90 degrees compared to the uninjured leg on the dial test confirms injury to both posterolateral capsule and PCL structures [31].
  • The reverse pivot shift test involves starting with the knee flexed to 90 degrees, extending the knee while applying axial load and valgus stress, and holding the foot in external rotation [31].
  • A palpable shift is noted during the reverse pivot shift test as the tibia reduces from its posteriorly subluxed position as the knee is extended [31].
  • The external rotation recurvatum test is performed with the patient supine and the hip and knee fully extended [31].
  • In the external rotation recurvatum test, the leg is lifted off the bed by the toes [31].
  • Hyperextension, varus instability, and external rotation of the tibial tubercle occur with adequate quadriceps relaxation in a patient with posterolateral instability during the external rotation recurvatum test [31].
  • The posterolateral drawer test is performed with the tibia in internal rotation, neutral, and externally rotated positions [31].
  • With posterolateral injury, the magnitude of the posterior drawer displacement is greatest with external tibial rotation [31].
  • An examination under anesthesia is extremely useful, particularly in the acute setting [31].
  • If a patient with a multiligamentous knee injury is taken to the operating room, examining the knee without guarding improves the accuracy of the examination [31].

Imaging Studies

  • A series of knee radiographs should be obtained in any patient with a suspected knee injury [31].
  • Radiographs should be inspected for acute fractures, lateral capsular avulsion (Segond fracture), loose bodies, fibular head avulsions, and evidence of patellar dislocation [31].
  • With chronic posterolateral instability, degenerative changes of the lateral compartment are often noted on radiographs [31].
  • Lateral joint space narrowing with osteophytes and subchondral sclerosis can be seen on radiographs in chronic posterolateral instability [31].
  • Stress radiographs can help to better quantify the amount of varus angulation present [31].
  • MRI is often a useful adjunct for diagnosing posterolateral corner and LCL injuries in the severely injured knee [31].
  • MRI findings can refocus the examination to the posterolateral structures when this injury has gone unnoticed during an initial evaluation [31].
  • Pain and guarding at the time of injury can often obscure posterolateral injury, making MRI an extremely valuable adjunct in diagnosis [31].
  • MRI should be obtained as a useful adjunct to help diagnose posterolateral corner injuries [31].
  • MRI may identify edema, avulsion, or discontinuity for the MCL/lateral collateral ligament (LCL) or associated posteromedial and posterolateral ligamentous complexes [22].

Non-Operative Management

  • Isolated grade I and II tears of the lateral collateral ligament (LCL) can be managed with nonsurgical treatment and early rehabilitation [5].
  • Nonsurgical management of isolated grade III LCL injuries produced poor results in clinical studies by Krukaug et al. and Kannus [5].
  • In a cohort of National Football League players, isolated grade III LCL injuries managed nonoperatively were as likely to return to play as those managed surgically and did so more quickly [5].
  • Despite controversial results regarding nonoperative management of grade III LCL injuries in NFL players, the authors recommended surgical treatment for most grade III injuries [5].

Operative Management

  • For acute lateral compartment disruptions, the knee is examined for instability classification and systematic grading after the patient has been anesthetized [5].
  • Systematic arthroscopic examination is usually carried out to assess and rule out other intraarticular pathologic conditions before proceeding with repair or reconstruction of the posterolateral corner [5].
  • Biomechanical studies have shown a significantly higher graft force during varus loading at 0 and 30 degrees of knee flexion after transection of the LCL than with intact posterolateral structures [5].
  • Posteromedial corner injuries have been implicated in anteromedial rotary instability and failed ACL reconstructions [5].
  • The anterolateral ligament (ALL) is not an isometric ligament; its length increases with knee flexion as well as internal rotation [5].
  • The ALL usually originates on the femur, posterior and proximal to the lateral femoral epicondyle, although some have located it either directly on the lateral epicondyle or anterior and distal to the attachment site of the LCL [5].
  • The tibial attachment site of the ALL resides halfway between the center of Gerdy’s tubercle and the anterior margin of the fibular head and 1 cm distal to the joint line [5].
  • The ALL has a mean ultimate load to failure between 50N and 205N, a mean stiffness of 20 to 42 N/mm, and a mean ultimate strain of 36% [5].
  • Cadaver and biomechanical studies have shown the importance of the ALL as a restraint to internal tibial rotation and anterior tibial translation and in preventing the knee pivot shift phenomenon [5].
  • Experimental sectioning of the ALL was found to invariably induce high-grade pivot shifts in ACL-deficient cadaver knees, unlike isolated ACL injury [5].
  • There is no consensus regarding the proper angle of knee flexion at which fixation of ALL reconstruction should occur [5].
  • Anatomic ALL reconstruction at all graft fixation angles significantly overconstrained internal rotation of the knee joint beyond 30 degrees of flexion and at 45 and 60 degrees during the pivot shift test [5].
  • There were no significant kinematic differences between any tested graft fixation angles during anterior drawer, pivot shift, and internal rotation tests [5].
  • Most authors report fixing the ALL reconstruction graft at 30 degrees of flexion to avoid overconstraint [5].
  • Sonnery-Cottet et al. reported full range of motion in 83 patients at a minimum 2-year follow-up after combined reconstructions of the ACL and ALL [5].
  • In the study by Sonnery-Cottet et al., 76 patients had a negative pivot shift and seven had a grade 1 pivot shift after combined ACL and ALL reconstruction [5].
  • Sonnery-Cottet et al. reported significant improvements in Lysholm scores, subjective IKDC scores, and objective IKDC scores after combined ACL and ALL reconstruction [5].
  • Sonnery-Cottet et al. found that ALL reconstruction protected the repaired medial meniscus [5].
  • Indications for combined ACL and ALL reconstructions reported by Sonnery-Cottet et al. include an associated Segond fracture, a chronic ACL lesion, grade 3 pivot shift, high level of sports activity, participation in pivoting sports, and lateral femoral notch sign on radiographs [5].
  • Other surgeons have included revision ACL reconstruction as an indication for ALL reconstruction [5].
  • In a study of 552 patients who had primary ACL reconstruction, Gaunder et al. identified 47 patients who required revision ACL reconstruction [5].
  • The incidence of Segond fractures was 6% in the primary ACL reconstruction group studied by Gaunder et al. [5].
  • After ACL reconstruction, the Segond fracture healed in 90% of patients in the study by Gaunder et al. [5].
  • No patient with revision surgery had a Segond fracture, and no patient with a Segond fracture had graft failure in the study by Gaunder et al. [5].

References

[1] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 3Sports Medicine > Image KNEE INJURIES.

[5] Campbell S Operative Orthopaedics 4 Volume Set. LATERAL COMPARTMENT (COLLATERAL) DISRUPTIONS.

[6] Aaos Comprehensive Orthopaedic Review 3. Anatomy and Biomechanics of the Knee > I. Anatomy.

[7] Miller S Review Of Orthopaedics. SECTION 1 KNEE > ANATOMY (FIG. 4.1).

[15] Orthopaedic Basic Science Fifth Edition Print Ebook. Biology and Mechanics of the Skeletal Extracellular Matrix > Gross Anatomy.

[18] Aaos Comprehensive Orthopaedic Review 3. Radiographic Evaluation and Surgical Anatomy of the Knee > II. Surgical Anatomy of the Knee.

[19] Miller S Review Of Orthopaedics. ARTHRODESIS PERSON > Kinetics.

[22] Aaos Comprehensive Orthopaedic Review 3. Radiographic Evaluation and Surgical Anatomy of the Knee > I. Radiographic Evaluation.

[24] Aaos Comprehensive Orthopaedic Review 3. Knee Dislocations and Patellar Fractures* > I. Knee Dislocations.

[31] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 3Sports Medicine > 2. Lateral Collateral Ligament Injuries.

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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.