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Lesión del ligamento colateral medial

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Updated Sep 2026
Illustration: knee

Esta página se tradujo automáticamente y todavía no la ha revisado un médico. La versión en inglés es la versión oficial.

Qué está sintiendo

El ligamento colateral medial se encuentra en la parte interna de su rodilla. Puede lesionarse cuando la rodilla recibe un empuje hacia el interior, o cuando se produce una torsión sin que nada impacte directamente contra ella. Las lesiones de menor gravedad suelen ocurrir durante una torsión; las lesiones de mayor gravedad, en cambio, suelen ser consecuencia de un impacto directo en la parte externa del muslo o de la parte superior de la pierna.

Sentirá dolor en la cara interna de la rodilla, a lo largo de la trayectoria del ligamento. La rodilla también puede sentirse inestable o “suelta”, sobre todo al soportar peso. La aparición inmediata de hinchazón es algo que debe comunicar a su cirujano, ya que puede indicar otras lesiones internas, como un desgarro del ligamento cruzado, una fractura o una rótula desplazada de su posición normal.

Con esta lesión, ciertas actividades resultan más difíciles. Caminar sobre terreno irregular puede generar sensación de inestabilidad. Levantarse de una silla baja implica cargar peso sobre la parte interna de la rodilla. Girar o pivotar sobre la pierna afectada, por ejemplo al rodear a alguien en un pasillo, puede provocar dolor. Al subir escaleras hay que tener cuidado, pues cada paso exige que la parte interna de la rodilla mantenga la estabilidad.

El dolor suele intensificarse tras realizar actividad física, una vez que la rodilla ha estado en uso durante un tiempo. También puede manifestarse como molestia nocturna, especialmente en los primeros días posteriores a la lesión. El reposo de la pierna y la evitación de movimientos de torsión suelen ayudar a aliviarlo.

Si la rodilla se siente inestable cuando está ligeramente flexionada, esto concuerda con un estiramiento o desgarro de este ligamento. Si, en cambio, se siente inestable con la pierna completamente extendida, podría indicar afectación de otros ligamentos situados en la parte posterior o central de la rodilla. Su cirujano evaluará ambas posiciones para determinar el alcance real de la lesión.

Las pruebas de imagen ayudan a confirmar el diagnóstico. La resonancia magnética permite identificar el punto exacto del desgarro y si el menisco u otras estructuras internas de la rodilla también resultaron dañadas. Los rayos X se utilizan para detectar fracturas, pequeños fragmentos óseos desprendidos por la lesión y la presencia de calcificaciones en el ligamento derivadas de lesiones previas.

¿Qué está ocurriendo realmente?

El ligamento colateral medial es una fuerte banda de tejido que recorre la parte interna de la rodilla, desde el fémur hasta la tibia. Puede considerarse como una de las cuerdas que mantienen firme una tienda de campaña. Cuando la rodilla se ve sometida a fuerzas que la empujan hacia adentro o la torsionan, esa “cuerda” se estira o se desgarra. El desgarro suele producirse en el punto donde el ligamento se une al fémur; ese lugar cuenta con buena irrigación sanguínea, por lo que estas lesiones suelen curarse por sí solas.

Los médicos clasifican la lesión según cuán inestable se sienta la rodilla. Una lesión de grado 1 implica que el ligamento está estirado, pero sigue cumpliendo su función. El grado 2 indica un desgarro parcial y una sensación de inestabilidad en la rodilla. El grado 3 significa que el ligamento está completamente roto y la rodilla resulta muy inestable. La mayoría de las lesiones de grados 1 y 2 se resuelven sin necesidad de cirugía. En cambio, es más probable que las lesiones de mayor grado afecten a otros ligamentos de la rodilla, especialmente al ligamento cruzado situado en el centro; esta combinación es lo que frecuentemente lleva a optar por la cirugía.

Cuando el ligamento interno se desgarra gravemente, la rodilla puede abrirse por el lado interno al recibir presión. Otras estructuras, como el ligamento cruzado, normalmente ayudan a mantener la estabilidad; por eso, cuando hay desgarros en varios lugares, la rodilla se siente mucho más inestable que cuando el desgarro es único. Algunas personas también sufren lesiones en el menisco, el tejido cartilaginoso que amortigua el contacto entre los huesos; sin embargo, esto es menos frecuente en este tipo de lesiones.

Si la lesión ocurrió hace mucho tiempo y nunca sanó adecuadamente, el cuerpo puede depositar pequeñas cantidades de calcio en el ligamento, cerca del fémur. Esto se observa en las radiografías y constituye una señal de que se trata de un problema crónico y persistente, no de una lesión reciente.

Qué podemos hacer al respecto

La mayoría de las lesiones del ligamento colateral medial no requieren cirugía. Normalmente comenzamos con el uso de una ortesis y fisioterapia. Una ortesis de rodilla con bisagras sirve para sostener el lado interno de la rodilla mientras el ligamento cicatriza. La fisioterapia tiene como objetivo controlar el dolor, restaurar el movimiento y recuperar la fuerza necesaria para mantener la estabilidad de la rodilla. Muchas lesiones se resuelven en semanas en lugar de meses; por ello, realizamos seguimientos periódicos para evaluar su evolución.

El alivio del dolor es sencillo: los analgésicos y antiinflamatorios comunes, tomados según las indicaciones, le ayudarán a sentirse cómodo y a seguir moviéndose mientras el ligamento sana.

La cirugía se considera cuando la rodilla sigue siendo inestable a pesar del uso de la ortesis y la fisioterapia, o cuando existen lesiones simultáneas en otros ligamentos de la rodilla. Un ligamento gravemente desgarrado que haya arrancado un fragmento óseo, o una rodilla que cede debido a lesiones en varios ligamentos, pueden requerir reparación o reconstrucción de forma temprana, en lugar de esperar. En esos casos, intervenimos para volver a fijar o reconstruir los ligamentos dañados y así recuperar la estabilidad de la rodilla. La operación en sí misma cuenta con su propia página informativa; antes de tomar cualquier decisión, le explicaremos en detalle en qué consiste.

Qué esperar

La mayoría de estas lesiones evolucionan favorablemente. Las lesiones de menor gravedad suelen curarse sin cirugía, en cuestión de semanas en lugar de meses. Primero disminuye el dolor; luego, a medida que se sigue el programa de fisioterapia, vuelven la fuerza y la estabilidad. Muchas personas recuperan la capacidad de caminar y realizar sus actividades diarias mucho antes de que el ligamento se haya curado por completo.

Si la lesión es más grave, o si al mismo tiempo se han desgarrado otros ligamentos de la rodilla, el pronóstico dependerá de recibir el tratamiento adecuado a tiempo. Cuando se lesionan tanto el ligamento interno como un ligamento cruzado, el tratamiento dirigido a ambos produce resultados similares a los obtenidos al tratar únicamente la lesión del ligamento cruzado. Algunas personas con esta combinación de lesiones vuelven a practicar deportes al nivel que hacían antes.

Si se deja sin tratar una rodilla que presenta inestabilidad en varias direcciones, esta inestabilidad suele persistir. La rodilla puede seguir siendo inestable al girar o pivotar, y con el tiempo las superficies cartilaginosas pueden desgastarse de forma desigual. La cirugía para reconstruir los ligamentos inestables puede devolverle la estabilidad; muchas personas vuelven después a sus actividades cotidianas y a practicar deporte de baja exigencia.

La recuperación tras la cirugía dura más que la recuperación de la propia lesión. Es normal que la rodilla se sienta rígida y tensa durante las primeras semanas; se necesitan meses de fisioterapia para recuperar la fuerza. Aun tras un buen resultado, algunas personas siguen percibiendo que su rodilla no es exactamente igual que antes. La cirugía en varios ligamentos a la vez conlleva más riesgos que la cirugía en uno solo: infección, rigidez, problemas en la cicatrización y lesión de un nervio situado en la parte externa de la rodilla, que puede provocar entumecimiento o debilidad en el pie.

Hay que tener cuidado de no esperar una solución inmediata. Por lo general el ligamento sana de manera fiable, pero la rodilla puede tardar meses en volver a sentirse fuerte y fiable. Si ya se ha sometido a una cirugía de ligamentos de rodilla, es posible que su rodilla no sea tan estable como antes. En las consultas de seguimiento, una vez que sepamos exactamente qué estructuras están lesionadas y cómo evoluciona su recuperación, analizaremos su pronóstico personal.

Cuándo consultar a un especialista

Acuda a su médico de cabecera si siente dolor en la cara interna de la rodilla tras un giro o un golpe, y este no mejora con el reposo durante las primeras dos semanas. Solicite una evaluación especializada si siente que la rodilla está inestable o cede al caminar, girar o pivotar, o si sigue hinchándose después de la actividad. Diríjase a urgencias si la rodilla se hincha de inmediato tras la lesión, si parece inestable cuando la pierna está completamente estirada, o si el pie se siente entumecido, débil o frío; estos síntomas pueden indicar desgarro de otros ligamentos, una fractura, un desplazamiento de la rótula o un problema nervioso que requiere atención inmediata.

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 & Ligament Structure

  • The medial collateral ligament (MCL) originates on the medial epicondyle and inserts 7 to 10 cm below the joint line on the posterior half of the medial surface of the tibial metaphysis deep to the pes anserinus tendons [6].
  • The MCL is a long, rather narrow, well-delineated structure lying superficial to the medial capsule and capsular ligaments [6].
  • The femoral insertion site of the superficial MCL is located a mean 1.6 mm posterior and 4.9 mm proximal to the intersection between a line paralleling the posterior femoral cortex and a line drawn perpendicular to the posterior femoral cortex, where it intersects the Blumensaat line [7].
  • The medial side of the knee is described in layers: layer 1 is the deep fascia, layer 2 is the superficial MCL, and layer 3 is the joint capsule and deep MCL [2].
  • The MCL receives its blood supply from the superior medial and inferior medial geniculate arteries [2].
  • The perpendicular mean distance from the saphenous nerve to the adductor tubercle or the medial epicondyle is 5 cm or 6.1 cm, respectively [7].
  • The perpendicular mean distance of the sartorial branch of the saphenous nerve to the anterior aspect of the superficial MCL is 4.8 cm at a point 2 cm distal to the joint line, 4.1 cm at 4 cm distal to the joint line, and 3.8 cm at 6 cm distal to the joint line [7].

Static & Dynamic Stabilizers

  • The superficial MCL is the primary restraint to valgus stress [2].
  • The deep MCL and posterior oblique ligaments (POL) form the secondary restraints to valgus stress [2].
  • The semimembranosus, vastus medialis, medial retinaculum, sartorius, semimembranosus, and gracilis act as dynamic stabilizers of the medial knee [2].
  • The medial capsuloligamentous complex comprises a three-layered sleeve of static and dynamic stabilizers extending from the midline anteriorly to the midline posteriorly [3].
  • Static stabilizers of the medial knee include the superficial MCL, the posterior oblique ligament, and the deep MCL (also called the deep medial ligament or middle capsular ligament) [3].
  • Dynamic stabilizers providing abduction stability under dynamic conditions include the semimembranosus complex, the pes anserinus muscle group (sartorius, gracilis, and semitendinosus muscles), the vastus medialis, and the medial retinaculum [3].
  • The superficial MCL with intact femoral and distal tibial attachments has the highest load to failure and stiffness among medial knee ligaments, followed by the POL and the deep MCL [7].

Biomechanics & Injury Mechanism

  • The main function of the medial capsuloligamentous complex is to resist valgus and external rotation loads [3].
  • The superficial MCL is the primary restraint to valgus loads at 30° of flexion [3].
  • The posterior oblique ligament, the deep MCL, and the cruciate ligaments are secondary restraints to valgus stress [3].
  • The MCL is the most commonly injured ligament in the knee [2].
  • The mechanism of MCL injury is a valgus and external rotation force to the lateral knee [2].
  • The most common injury location for the MCL is the femoral insertion, which has great healing potential [2].
  • Distal ruptures of the MCL are less common and more often lead to residual valgus laxity [2].
  • In a healthy knee, the anterior bundles of both the superficial and deep MCL elongate during knee flexion, while the posterior bundles distend with knee flexion [7].
  • The elongation of the posterior bundles of the MCL peaks at midstance and the terminal extension–preswing stance phase [7].
  • Isolated grade III superficial MCL injury in a cadaver model resulted in a mean increase of 3.2 mm in medial joint line opening [7].
  • In a cadaver model, medial joint line opening increased to 8.8 mm when the deep MCL and posterior oblique ligament were injured, and to 13.8 mm when ACL injury was added [7].
  • A cutoff distance of 3.2 mm of medial joint line opening was established as the basis for suspecting an isolated grade III superficial MCL injury [7].
  • The ultimate tensile strength of the MCL is twice that of the LCL, although there is no significant difference in stiffness between the two [7].
  • The MCL was most commonly torn at the femoral insertion site in biomechanical studies [7].
  • Only a few fibers of the MCL radiate to the medial meniscus, and meniscal displacement does not significantly differ between a healthy MCL and an MCL detached from the femoral insertion [7].

Injury Classification & Pathophysiology

  • Grade I MCL injury involves minimal torn fibers with 1 to 4 mm opening on valgus stress at 30° [2].
  • Grade II MCL injury involves partial tearing of the fibers with 5 to 10 mm laxity at 30° and a firm end point [2].
  • Grade III MCL injury is a complete tear with >10 mm opening without an end point [2].
  • Grade I MCL sprain is characterized by few torn fibers with no loss of ligamentous integrity [3].
  • Grade II MCL sprain is characterized by incomplete ligament tearing with increased joint laxity, maintenance of an end point to valgus stress at 30° of flexion, and continued fiber apposition despite partial tearing [3].
  • Grade III MCL sprain is characterized by complete ligamentous disruption resulting in gross laxity without a palpable end point to valgus stress [3].
  • Concomitant ligamentous injuries occur in 20% of grade I, 52% of grade II, and 78% of grade III MCL injuries [3].
  • Concurrent meniscal injuries have been noted in up to 5% of isolated MCL injuries [3].
  • Chronic MCL injuries may present with calcification at the insertion of the MCL on the medial femoral condyle [1].
  • A Pellegrini-Stieda lesion is a calcification at the medial femoral insertion site resulting from chronic MCL deficiency [2].
  • High-grade medial instability or an MCL tear with an associated tear of the posterior horn of the medial meniscus should raise suspicion for posteromedial corner (PMC) instability [8].
  • All patients with grade III laxity of the MCL had a complete tear of the POL and meniscotibial ligament in an MRI-based retrospective study [8].
  • All patients with injury to the posterior horn of the medial meniscus had concomitant meniscotibial ligament injury, and 67% had a tear of the POL [8].
  • 81% of patients with a confirmed knee dislocation or a knee dislocatable under anesthesia had an injury to the PMC, and 63% had a superficial MCL tear alone [8].

Clinical Presentation

Mechanism of Injury

  • MCL injuries occur after a valgus stress to the knee or a noncontact rotational injury [1].
  • Lower-grade MCL injuries typically occur in a noncontact external rotational injury [1].
  • Higher-grade MCL injuries generally involve lateral contact to the thigh or upper leg [1].

Symptoms and History

  • The location and presence of pain, instability, timing of swelling, and sensation of a “pop” or tear are important pieces of historical information [1].
  • Grade I and II MCL injuries are often more painful than complete MCL rupture [1].
  • Immediate swelling should make one suspicious for an associated cruciate ligament injury, fracture, and/or patellar dislocation [1].
  • A prior history of knee injuries or instability should always be sought when evaluating a new knee injury [1].

Physical Examination

  • Medial joint line tenderness along the course of the MCL is typical at the location of the tear [1].
  • Laxity to valgus stresses is assessed by the amount of medial joint space opening that occurs at 30 degrees of flexion [1].
  • The knee must be stressed at 30 degrees of flexion because with the knee in full extension the posterior capsule and PCL will stabilize the knee to valgus stress [1].
  • Stability to valgus stress in full extension could mislead the examiner to believe that the MCL is intact [1].
  • Zero opening is considered normal for medial joint space opening [1].
  • 1–4 mm of medial joint space opening indicates a grade I injury [1].
  • 5–9 mm of medial joint space opening indicates a grade II injury [1].
  • 10–15 mm of medial joint space opening indicates a complete or grade III injury [1].
  • Grade I and II injuries typically have a firm end point to valgus stress [1].
  • A grade III injury tends to have a soft end point to valgus stress [1].
  • Medial knee pain and instability at 30 degrees of flexion is diagnostic of MCL injury [1].
  • If opening occurs at full extension with a valgus stress, ACL or PCL injuries should be considered in addition to MCL injury [1].
  • Palpation of the patella and the medial parapatellar stabilizing ligaments should be performed in addition to patellar apprehension testing due to the frequency of coexisting patellar dislocations in MCL injuries [1].

Imaging

  • Chronic MCL injuries may have calcification at the insertion of the MCL on the medial femoral condyle [1].
  • Radiographs should be inspected for acute fracture, lateral capsular avulsion (Segond fracture), loose bodies, Pellegrini-Stieda lesion (MCL calcification), and evidence of patellar dislocation [1].
  • Stress radiographs should be obtained in patients prior to skeletal maturity to rule out an epiphyseal fracture [1].
  • MRI can be helpful in confirming diagnosis and helping to rule out concomitant meniscal injury [1].
  • MRI is useful for confirming MCL injury and identifying the site of injury [1].
  • MRI is useful to detect the presence of meniscal and other injuries to the knee [1].
  • Relative indications for an MRI include an uncertain ACL status despite multiple examinations, evaluation of a suspected meniscal tear, or preoperative evaluation for a planned MCL reconstruction or repair [1].
  • An examination under anesthesia can be valuable when physical examination is unreliable because of the patient guarding the knee [1].
  • Diagnostic arthroscopy can be used to evaluate for coexisting pathology [1].
  • Examination under anesthesia and diagnostic arthroscopy have largely been replaced by MRI [1].

Investigations

Physical Examination

  • Medial knee pain and instability at 30 degrees of flexion is diagnostic for MCL injury [1].
  • Opening at full extension with a valgus stress suggests concomitant ACL or PCL injuries in addition to MCL injury [1].
  • Laxity to valgus stress is assessed by the amount of medial joint space opening at 30 degrees of flexion [1].
  • The knee is stressed at 30 degrees of flexion because the posterior capsule and PCL stabilize the knee to valgus stress in full extension, which could mislead the examiner into believing the MCL is intact [1].
  • Zero opening to valgus stress is considered normal [1].
  • Medial joint space opening of 1–4 mm indicates a grade I MCL injury [1].
  • Medial joint space opening of 5–9 mm indicates a grade II MCL injury [1].
  • Medial joint space opening of 10–15 mm indicates a complete or grade III MCL injury [1].
  • Grade I and II MCL injuries typically have a firm end point to valgus stress [1].
  • Grade III MCL injuries tend to have a soft end point to valgus stress [1].
  • Valgus stress should be applied at both 0° and 30° of flexion [2].
  • Opening at 0° of flexion indicates a posteromedial capsular or associated cruciate (ACL/PCL) injury [2].
  • An effusion may indicate associated intra-articular pathology [2].
  • Abduction stress testing should be performed with the knee at 0° and 30° of flexion [3].
  • The superficial MCL is isolated with a valgus stress at 30° of flexion [3].
  • Pathologic laxity is indicated by the amount of increased medial joint space separation compared with the opposite, normal knee [3].
  • Grade I MCL injury is characterized by 1 to 4 mm of laxity [3].
  • Grade II MCL injury is characterized by 5 to 9 mm of laxity [3].
  • Grade III MCL injury is characterized by ≥10 mm of laxity [3].
  • Valgus laxity with the knee at or near full extension implies concurrent injury to the posteromedial capsule and/or cruciate ligaments [3].
  • Isolated laxity at 30° and stability in 0° of extension indicates either a grade I or II injury [3].
  • Combined laxity at 0° and 30° indicates a grade III injury with concurrent injury to the posteromedial capsule, and ACL or PCL combined injury should be considered [3].
  • The Lachman and anterior drawer tests should be performed to rule out an ACL injury [3].
  • The pivot shift test often has false-negative results in the presence of a grade III MCL sprain [3].
  • A PCL injury is assessed by palpation of the tibial-condylar step-off and by the posterior drawer test (both performed at 90° of flexion), the quadriceps-active test, and observation of posterior tibial sag [3].
  • Patellar apprehension and tenderness over the patella and medial retinaculum indicate possible patellar dislocation or subluxation [3].
  • Diagnosis of an isolated medial meniscal injury is suggested by medial joint line tenderness, the absence of pain to valgus stress, and increased pain on flexion-rotation testing (McMurray test) [3].

Imaging

  • Plain radiographs should be performed to rule out fracture [2].
  • A Pellegrini-Stieda lesion can be seen on radiographs, which is a calcification at the medial femoral insertion site resulting from chronic MCL deficiency [2].
  • MRI is not routinely necessary unless concomitant injuries are suspected [2].
  • Plain radiographs are typically normal but should be inspected for fractures, lateral capsular avulsions (Segond fracture associated with an ACL tear), and Pellegrini-Stieda lesions (indicative of prior MCL injury) [3].
  • Stress radiographs may be indicated in skeletally immature patients to rule out a physeal injury [3].
  • MRI has become the imaging modality of choice to evaluate the injured MCL [3].
  • MRI advantages include identifying the location and extent of injury and ruling out associated meniscal, chondral, and cruciate ligament injuries [3].
  • MRI disadvantages include being expensive, reader-dependent, and potentially overestimating the degree of injury [3].

Treatment

Non-Operative Management

  • Nonoperative treatment using a hinged knee brace is highly successful in alleviating isolated MCL injuries [4].
  • Clinical work has shown the advantage of nonoperative treatment (bracing) for an associated MCL injury in patients undergoing an ACL reconstruction [4].
  • Prophylactic bracing may be helpful for football players, especially interior linemen [4].
  • Pellegrini-Stieda syndrome, which can occur with chronic MCL injury, usually responds to a brief period of immobilization followed by progressive motion [4].

Operative Management

  • Advancement and reinforcement of the ligament are rarely necessary for chronic injuries that do not respond to conservative treatment [4].
  • Distal (tibia-side) injuries have less healing potential than proximal (femur-side) injuries [4].
  • The management algorithm for isolated grade III MCL injury or MCL with associated injuries includes MRI, rehabilitation, and physical therapy to regain motion [4].
  • The management algorithm for femoral avulsion involves MCL repair or reconstruction [4].
  • The management algorithm for tibial avulsion involves MCL repair or reconstruction [4].
  • The management algorithm for ACL/MCL injuries involves ACL reconstruction and rehabilitation to regain full range of motion [4].

References

[1] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 3Sports Medicine > 1. Medial Collateral Ligament Injuries.

[2] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Soft-­Tissue Injuries About the Knee > Medial Collateral Ligament.

[3] Aaos Comprehensive Orthopaedic Review 3. Ligamentous Injuries of the Knee > III. Medial Collateral Ligament and Posteromedial Corner Injuries.

[4] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > 3. MCL injury.

[6] Campbell S Operative Orthopaedics 4 Volume Set. MEDIAL COLLATERAL LIGAMENT.

[7] Orthopaedic Knowledge Update Sports Medicine 6. Collateral Ligament Injuries > The Medial Collateral Ligament > Anatomy and Biomechanics.

[8] Orthopaedic Knowledge Update Sports Medicine 6. Collateral Ligament Injuries > The Medial Collateral Ligament > PMC and Other Combined Injuries.

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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.