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Patients › Knee

ACL reconstruction

PDF Evidence Consent
Updated Sep 2026
Illustration: knee

Why this operation has been suggested

Scans such as an MRI are good at confirming a torn anterior cruciate ligament, the strap of tissue inside the knee that stops the shin bone sliding too far forward.

The anterior cruciate ligament cannot heal itself, so a reconstruction rebuilds it with a new piece of tendon. We usually offer this operation to people who are young or active, or whose knee gives way. Treatment is tailored to your age, activity level, how unstable your knee feels and any other injuries. Many people first try physiotherapy to restore movement and build thigh muscle strength, and surgery follows when that has not given enough improvement. The aim is a knee that feels steady, so you can move and stay active without it giving way.

Before the operation

In the weeks before surgery you will work with a physiotherapist to straighten and bend the knee fully and build up the thigh muscles. Doing this first makes recovery after the operation smoother. You will also have scans to help plan the operation, such as an X-ray or MRI. On the day, stop eating and drinking seven hours beforehand; we ask for a little longer than the standard six hours so your surgery can be brought forward if the list runs early. Your surgeon will tell you which medicines to pause. Arrange for someone to drive you home, and bring a list of your current medications. Wear loose, comfortable clothing. If you have other medical conditions, you may need blood tests or a review with the anaesthetist.

On the day

You arrive at the hospital's surgical admissions unit, where you are checked in and prepared for theatre. You will meet the anaesthetist, the doctor who puts you to sleep and keeps you comfortable during the operation. This operation is done under general anaesthetic. A regional nerve block is sometimes added for post-operative pain relief; the anaesthetist will discuss this with you on the day.

You are then taken into the operating theatre, where the operation is performed. Afterwards you wake up in the recovery area, where nurses watch over you while the anaesthetic wears off. Once you are stable, you either move to a ward or go home the same day, depending on the procedure and how your recovery is going.

What the operation involves

A reconstruction replaces the torn ligament with a new piece of tendon, called a graft. The graft can come from your own body, most often from the front of the knee or from the hamstring tendons at the back of the thigh, or from donor tissue. Your surgeon chooses the graft that suits your knee, your age and the activities you want to return to.

The operation is done through small cuts around the knee using a thin camera called an arthroscope, which lets your surgeon see inside the joint. The torn ligament is confirmed and the knee is checked for any other damage, such as a torn cartilage. Small tunnels are drilled in the shin bone and thigh bone, and the new graft is threaded through them so it sits where the old ligament used to be. The graft is then held in place with screws or buttons while it heals into the bone.

The cuts are closed with stitches and covered with a dressing. You will go home with written instructions on caring for the wounds.

Some tears can be repaired rather than rebuilt, but this suits only a small group of patients, usually where the ligament has torn cleanly off the bone and the tissue quality is good. Your surgeon will tell you if a repair is an option for you.

After the operation

When you wake up from the anaesthetic you will be in the recovery area, and once you are stable you will move to a ward or go home. Your team will tell you whether you go home the same day or stay one night in hospital. Nurses will keep you comfortable and give you pain relief as needed. Your knee will have a dressing on the wounds, and you may have a support bandage rather than a brace. Most people stand and take a few steps with a frame or crutches on the day of surgery, with a physiotherapist helping you. Please arrange for someone to stay with you for the first 24 hours after you get home. We leave the dressing on for about 10 days; please do not take it off before then unless we tell you to. We change or remove it when we see you.

Recovery

The first days are about comfort and gentle movement. Your knee will be sore and swollen, and it may feel warm. Rest, ice and the pain relief your team prescribes all help. Keep the leg raised when you are sitting or lying down. The swelling usually peaks in the first few days, then settles gradually over the following weeks.

You will see a physiotherapist soon after surgery, and you will keep working with them as your knee recovers. Early exercises focus on straightening the knee fully, bending it a little further each day and switching the thigh muscles back on. Walking starts with crutches or a frame, and you will put weight through the leg as your physiotherapist advises. You may have a support bandage rather than a brace. You can do most things at home once you feel steady: move around the house, prepare meals and go up and down stairs carefully. Avoid twisting, pivoting or kneeling until your knee is ready.

As the swelling settles and movement returns, the exercises become harder. You will build strength in the thigh muscles and practise balance and control. Later stages prepare you for the activities you want to get back to, such as running, jumping or changing direction. Some people also complete a structured return-to-sport program on top of normal physiotherapy before they are cleared for unrestricted sport.

Recovery varies from person to person. Your timeline may differ, and your surgeon and physiotherapist will guide you at each stage.

What can go wrong

Most patients do well, but problems can occasionally happen. Your surgeon and the team monitor you closely to spot any issue early.

Stiffness in the knee. Some people develop tightness that limits how far the knee bends or straightens. You might notice the knee feels locked or will not fully straighten, even with effort. Doing your exercises and getting full movement back before surgery lowers this risk. Tell your physiotherapist or call the clinic if the knee will not straighten.

Infection. This is uncommon, but watch for a deep, throbbing pain that does not ease with simple painkillers, redness spreading out from the wound, or feeling feverish and unwell. The knee may become hot, swollen and very tender. If you notice any of these signs, call the clinic straight away or go to the emergency department. Infection is treated with a washout of the joint and antibiotics, and the graft can often stay in place.

The new ligament tearing again. The graft can tear, just as the original ligament did. This usually happens with a twist or a fall, and it feels like the knee giving way again, often with swelling. If this happens, contact the clinic. A second operation to rebuild the ligament is possible, though recovery after that operation is usually slower and the results are not as predictable as the first time.

Injuring the ligament in the other knee. The ligament in your other knee can also tear, especially in young people returning to sport. Taking your time with the return-to-sport program before going back protects both knees.

Pain at the front of the knee. If the graft was taken from the front of the knee, that area can stay sore, particularly with kneeling, and the thigh muscle can be slower to regain strength. Mention this at your review if it limits you.

The complications table on this page lists typical rates if you want the specifics.

When to call us

Most problems show up early, and we would rather hear about them sooner than later. Call us if you have a fever, if the skin around the wound becomes redder or starts leaking fluid, or if the knee becomes hot, swollen and increasingly painful. Go to emergency if you have sudden severe pain, swelling in your calf, or shortness of breath, because these can signal a blood clot. Also go to emergency if your leg goes numb, feels cold or changes colour, or if you cannot move it.

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

Anatomy & Pathophysiology

Epidemiology & Risk Factors

  • ACL injury accounts for between 40% and 50% of all knee ligament injuries [6, 7].
  • Female athletes have a two to eight times higher risk of ACL tear than male athletes [6, 7].
  • The increased risk in female athletes is thought to occur because women have different landing biomechanics, specifically greater total valgus knee loading in landing and landing more erectly [6, 7].
  • Female athletes have increased quadriceps-to-hamstring strength, which causes greater anterior shear [6, 7].
  • Proposed additional risk factors for ACL injury include smaller notches, smaller ligaments (reduced area in cross section), greater generalized ligament laxity, increased knee laxity, and absence of the COL5A1 gene [6, 7].
  • Skiing, soccer, basketball, and football are the highest-risk sports for ACL injury [6, 7].

Mechanism & Biomechanics

  • The mechanism of ACL injury is typically a valgus load with internal tibial rotation and anterior tibial translation while the knee is in almost full extension [6, 7].
  • The in situ force of the ACL is highest at 30 degrees of flexion in response to anterior tibial load [6, 7].
  • The anteromedial bundle of the ACL provides anterior restraint and is evaluated by Lachman and anterior drawer tests [6, 7].
  • The posterolateral bundle of the ACL provides rotatory restraint and is evaluated by the pivot shift test [6, 7].

Associated Injuries

  • Associated injuries are common with ACL tears [6, 7].
  • Acute lateral meniscal tears are more common than acute medial tears, whereas medial tears occur more often with chronic ACL deficiency [6, 7].
  • MCL injuries occur in approximately 25% of cases and are typically treated nonoperatively [6, 7].
  • PLC injuries occur in approximately 10% of cases [6, 7].
  • Lack of recognition of a PLC injury has been cited as a common cause of ACL reconstruction failure [6, 7].
  • Chronic ACL deficiency is associated with higher incidences of both complex meniscal tears not amenable to repair and chondral injury [6, 7].

Pathophysiology & Long-term Outcomes

  • Currently there is no high-level evidence to suggest that ACL reconstruction reduces the risk of development of arthritis [6, 7].
  • Chondral and meniscal injuries that occur at the time of initial ACL rupture have been demonstrated to be the main predictors of arthritic change [6, 7].
  • The most common reasons for failure to return to play or sport after ACL reconstruction are pain and fear of reinjury [6, 7].
  • Primary repair of ACL tears is not currently recommended because myofibroblasts “coat” the ends of the ACL stumps, making primary healing unlikely [1, 2].
  • Arthrofibrosis is the most common complication following ACL reconstruction and often occurs with reconstruction for acute ACL tears [1, 2].
  • The risk of arthrofibrosis is minimized by the achievement of full range of motion prior to surgery [1, 2].
  • In skeletally immature patients, the most common complications after ACL reconstruction include arthrofibrosis, growth disturbance, and secondary injury of the same or the contralateral ACL [3].
  • An overall incidence of arthrofibrosis of 8.3% was reported in a cohort of 902 young patients (average age = 15 years) treated with ACL reconstruction [3].
  • Risk factors for arthrofibrosis in young patients include female sex, older age, the use of bone–patellar tendon–bone autograft, and concomitant meniscal repair [3].
  • Growth arrest can occur after ACL reconstruction in skeletally immature patients despite efforts to avoid this complication [3].
  • Clinically important growth disturbances, including tibial recurvatum and genu valgum, have been reported after transphyseal ACL reconstruction using physeal-respecting techniques [3].
  • Focal physeal bone bridges were noted in five knees in a review of 43 patients who underwent transphyseal ACL reconstruction using soft-tissue graft, although no patient had resultant limb deformity [3].
  • Growth disturbance has been reported with physeal-sparing techniques, with one patient in a series of all-epiphyseal ACL reconstructions developing clinically significant growth arrest [3].
  • The incidence of second ACL injury in young athletes (average age = 17 years) within 2 years of the index surgery is more than five times greater than that of healthy control athletes [3].
  • Nearly 30% of young athletes sustained a second ACL injury within 24 months of return to sports, with approximately one-third of the injuries occurring in the ipsilateral knee and two-thirds in the contralateral knee [3].
  • Patients younger than 20 years at the time of ACL reconstruction had a 29% chance of sustaining a second ACL injury (either knee) within 5 years of the index surgery [3].
  • In a cohort of 85 patients younger than 18 years, 32% sustained a second ACL injury, with later return to sport being protective against new ACL injury [3].
  • Athletes younger than 25 years who return to sports had a secondary rate of ACL injury (ipsilateral or contralateral knee) of 23% [3].

Clinical Evaluation

  • Young athletes with ACL tears frequently report the sudden onset of knee pain that may be accompanied by a popping sensation after a noncontact, twisting-type injury [4].
  • Difficulty bearing weight and hemarthrosis are commonly present in acute ACL tears [4].
  • Clinical tests for ACL deficiency include the Lachman, anterior drawer, and pivot shift tests [4].
  • Results of clinical tests for ACL deficiency should be compared with similar tests performed on the contralateral, unaffected knee, particularly in young, anxious patients [4].
  • The presence of associated meniscal injuries may be established by evaluating for tenderness of the joint line and decreased passive knee motion [4].
  • Injuries of the collateral ligaments may be evaluated by varus and valgus stress testing of the knee performed at 0° and 30° of flexion [4].
  • MRI of the knee has a sensitivity of 95% and specificity of 88% for confirming an ACL tear [4].
  • MRI is helpful for elucidating additional injuries and assessing physeal patency in skeletally immature patients [4].
  • A bone age study is generally performed for skeletally immature patients to estimate the amount of remaining skeletal growth before surgical treatment [4].
  • Standing hip-to-ankle alignment radiographs may be obtained to evaluate for preexisting angular deformity or limb-length discrepancy before surgical intervention [4].

Clinical Presentation

History and Symptoms

  • Young athletes with ACL tears frequently report the sudden onset of knee pain after a noncontact, twisting-type injury [4].
  • The onset of knee pain in young athletes with ACL tears may be accompanied by a popping sensation [4].
  • Difficulty bearing weight is commonly present in young athletes with ACL tears [4].
  • Hemarthrosis is commonly present in young athletes with ACL tears [4].

Physical Examination

  • Initial evaluation includes inspecting the soft tissues of the affected limb [4].
  • Initial evaluation includes performing passive motion of the ipsilateral hip, knee, and ankle [4].
  • Initial evaluation includes carefully palpating the entire affected limb [4].
  • Initial evaluation includes assessing neurovascular status [4].
  • Clinical tests for ACL deficiency include the Lachman test [4].
  • Clinical tests for ACL deficiency include the anterior drawer test [4].
  • Clinical tests for ACL deficiency include the pivot shift test [4].
  • Clinical tests for ACL deficiency may be difficult to perform and/or interpret in a young, anxious patient [4].
  • Results of clinical tests for ACL deficiency should be compared with similar tests performed on the contralateral, unaffected knee [4].
  • Clinical tests for ACL deficiency may need to be repeated in a young, anxious patient [4].
  • The presence of associated meniscal injuries may be established by evaluating for tenderness of the joint line [4].
  • Decreased passive knee motion may indicate a meniscal injury with displacement [4].
  • The dial test can be performed to evaluate the posterolateral corner of the knee [4].
  • The posterior drawer test can be performed to evaluate the posterior cruciate ligament [4].
  • Limb alignment and lengths are assessed clinically if ACL injury is suspected in a skeletally immature patient [4].
  • The patient’s degree of physiologic maturity may be gauged by use of Tanner staging of sexual maturation in skeletally immature patients [4].

Imaging

  • Orthogonal radiographs of the affected knee should be obtained [4].
  • Additional radiographs should be obtained as suggested by the physical examination findings [4].
  • MRI of the knee has a 95% sensitivity for confirming an ACL tear [4].
  • MRI of the knee has an 88% specificity for confirming an ACL tear [4].
  • MRI of the knee is helpful for elucidating additional injuries [4].
  • MRI of the knee is helpful for assessing physeal patency [4].
  • A bone age study is generally performed for skeletally immature patients before surgical treatment to estimate the amount of remaining skeletal growth [4].
  • A bone age study consists of a PA radiograph of the left hand compared with the Greulich and Pyle atlas of normal standards [4].
  • Standing hip-to-ankle alignment radiographs may be obtained to evaluate for preexisting angular deformity before surgical intervention [4].
  • Standing hip-to-ankle alignment radiographs may be obtained to evaluate for limb-length discrepancy of the lower limbs before surgical intervention [4].

Investigations

  • In young, anxious patients, results of clinical tests for ACL deficiency should be compared with similar tests performed on the contralateral, unaffected knee and may need to be repeated [4].
  • If ACL injury in a skeletally immature patient is suspected, limb alignment and lengths are assessed clinically [4].
  • The patient’s degree of physiologic maturity may be gauged by use of Tanner staging of sexual maturation [4].
  • Orthogonal radiographs of the affected knee should be obtained, with additional radiographs obtained as suggested by the physical examination findings [4].
  • MRI of the knee is helpful for elucidating additional injuries and assessing physeal patency [4].
  • Before surgical treatment, a bone age study (a PA radiograph of the left hand compared with the Greulich and Pyle atlas) is generally performed for skeletally immature patients to estimate the amount of remaining skeletal growth [4].
  • Standing hip-to-ankle alignment radiographs may be obtained to evaluate for preexisting angular deformity or limb-length discrepancy of the lower limbs before surgical intervention [4].
  • A thorough workup of failed ACL reconstruction should include acquiring prior imaging and considering all causes of graft failure, including technical issues, unrecognized concomitant ligament injuries, coronal or sagittal malalignment, biological failure of graft incorporation, and other patient-related issues [1].

Treatment

Non-Operative Management

  • Initial management of ACL injury consists of physical therapy to restore motion [1].
  • Immobilization is avoided in the initial management of ACL injury [1].
  • Full range of motion (ROM) and good quadriceps control should be achieved prior to surgery [1].
  • Treatment should be individualized based on age, activity level, instability, associated injuries, and other medical factors [1].

Surgical Technique

  • Primary repair of ACL tears is not currently recommended [1].
  • Myofibroblasts "coat" the ends of the ACL stumps, making primary healing unlikely [1].
  • Single-bundle reconstruction is the most commonly performed ACL reconstruction technique [1].
  • There is currently no difference in patient-reported outcomes between single-bundle and double-bundle ACL reconstruction techniques [1].
  • Independent femoral tunnel drilling techniques focus on placing a more horizontal femoral tunnel (10- or 2-o’clock position) to center the graft in the middle of the femoral ACL footprint [1].
  • A more horizontal graft position may reduce rotational instability [1].
  • Graft selection for ACL reconstruction depends on patient factors and surgeon preference [1].
  • Common graft choices for ACL reconstruction include bone–patellar tendon–bone (BPTB) autograft, four-strand hamstring autograft, quadriceps tendon autograft, and allograft [1].
  • BPTB autograft demonstrates faster incorporation into bone tunnels than hamstring autograft [1].
  • BPTB autograft is often the graft of choice for patients who desire an early return to sports activity [1].
  • Several studies have demonstrated a higher incidence of arthritis associated with the use of BPTB autograft than with hamstring autograft 5 to 7 years after ACL reconstruction [1].
  • BPTB autograft harvest carries the risk of anterior knee pain, pain with kneeling, loss of extension, and poorer recovery of quadriceps strength [1].
  • Hamstring autograft is similar in strength to the native ACL but is less stiff [1].
  • Hamstring autograft harvest carries the risk of weakness of knee flexion and internal rotation, along with injury to branches of the saphenous nerve [1].
  • Both BPTB and quadriceps tendon with bone block grafts carry the risk of patellar fracture [1].
  • Use of allograft with ACL reconstruction in younger, more active patients is associated with a higher rate of rerupture [1].
  • Chemically processed and irradiated allografts have demonstrated higher rates of failure than fresh frozen allografts [1].
  • Allografts have been demonstrated to incorporate into bone tunnels more slowly than autografts [1].
  • Use of allograft includes infection risk with Clostridium species, hepatitis, and human immunodeficiency virus (HIV), although rates are low at 1:1.6 million [1].
  • Preimplantation culture of allografts is not widely recommended [1].

Postoperative Rehabilitation

  • Most postoperative rehabilitation protocols encourage early motion with an emphasis on extension and weight bearing [1].
  • Exercises that do not endanger the ACL graft are dominated by the hamstrings, such as isometric hamstrings [1].
  • Exercises that do not endanger the ACL graft involve active knee ROM between 35 and 90 degrees of flexion [1].
  • Closed kinetic chain rehabilitation and compressive loading are emphasized because they allow physiologic cocontraction of the muscles around the knee [1].
  • Open kinetic chain extension exercises, particularly with the knee near full extension, place increased stress on the reconstructed ACL and should be avoided for the first 6 weeks [1].
  • No difference in outcome has been found between accelerated and nonaccelerated rehabilitation programs [1].
  • Postoperative bracing has not proved beneficial after ACL reconstruction except in downhill skiers [1].
  • Early progressive eccentric exercise has yielded good initial results in terms of muscle size and function after ACL reconstruction [1].

Complications

  • The most common technical error leading to graft failure is tunnel malposition [1].
  • Vertical graft placement results in decreased rotational stability [1].
  • Anterior placement of the femoral tunnel results in flexion loss [1].
  • Arthrofibrosis is the most common complication following ACL reconstruction [1].
  • Arthrofibrosis often occurs with reconstruction for acute ACL tears [1].
  • The risk of arthrofibrosis is minimized by the achievement of full ROM prior to surgery [1].
  • Aberrant hardware placement, defined as interference screw divergence of >30 degrees for femoral tunnels or >15 degrees for tibial tunnels, can result in complications [1].
  • Infection occurs in less than 1% of ACL reconstruction cases [1].
  • Irrigation and débridement with graft retention are successful in up to 85% of post-ACL reconstruction infection cases [1].

Revision ACL Reconstruction

  • Causes of graft failure in revision ACL reconstruction include technical issues, unrecognized concomitant ligament injuries, coronal or sagittal malalignment, biological failure of graft incorporation, and other patient-related issues [1].
  • A thorough workup of failed ACL reconstruction should include acquiring prior records [1].

Complications

General Complications

  • Graft failure is a complication of ACL reconstruction [1].
  • Irrigation and débridement with graft retention are successful in up to 85% of infected ACL reconstruction cases [1].

Skeletally Immune Patients

  • The most common complications occurring after ACL reconstruction in skeletally immature patients include arthrofibrosis, growth disturbance, and secondary injury of the same or the contralateral ACL [3].
  • In a retrospective case series of 902 young patients (average age 15 years) treated with ACL reconstruction, the overall incidence of arthrofibrosis was 8.3% [3].
  • Female sex, older age, the use of bone–patellar tendon–bone autograft, and concomitant meniscal repair are additional risk factors for arthrofibrosis in skeletally immature patients [3].
  • Growth arrest can occur after ACL reconstruction in skeletally immature patients despite the use of physeal-respecting techniques [3].
  • In a case series of four patients (average age 14.2 years) who underwent transphyseal ACL reconstruction using physeal-respecting techniques, clinically important growth disturbances including tibial recurvatum and genu valgum developed [3].
  • In a retrospective review of 43 patients (average age 14.8 years) who underwent transphyseal ACL reconstruction using soft-tissue graft, focal physeal bone bridges were noted in five knees, although no patient had resultant limb deformity [3].
  • Growth disturbance has been reported with physeal-sparing techniques, including one patient in a series of all-epiphyseal ACL reconstructions who developed clinically significant growth arrest [3].
  • In a 2014 cohort study of young athletes (average age 17 years), nearly 30% sustained a second ACL injury within 24 months of return to sports [3].
  • In the same 2014 cohort study, approximately one-third of second ACL injuries occurred in the ipsilateral knee and two-thirds in the contralateral knee [3].
  • In a 2014 case-control study, patients younger than 20 years at the time of ACL reconstruction had a 29% chance of sustaining a second ACL injury within 5 years of the index surgery [3].
  • In a cohort of 85 patients younger than 18 years who underwent primary ACL reconstruction with autograft, 32% sustained a second ACL injury [3].
  • A systematic review and meta-analysis found that athletes younger than 25 years who return to sports had a secondary rate of ACL injury (ipsilateral or contralateral knee) of 23% [3].

References

[1] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > 1. ACL injury > Treatment.

[2] Miller S Review Of Orthopaedics. 1. ACL injury > Treatment.

[3] Orthopaedic Knowledge Update. Ligamentous Knee Injuries > ACL Injuries > Complications.

[4] Orthopaedic Knowledge Update. Ligamentous Knee Injuries > ACL Injuries > Evaluation.

[6] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > 1. ACL injury > Introduction.

[7] Miller S Review Of Orthopaedics. 1. ACL injury > Introduction.

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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.