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Patients › Knee

Unicompartmental knee replacement

PDF Evidence Consent
Updated Sep 2026
Illustration: knee

Why this operation has been suggested

This operation replaces one worn part of the knee with an artificial surface. The name means replacement of one compartment, one of the three areas where the knee bones meet. We usually suggest it when wear-and-tear arthritis, called osteoarthritis, is limited to that one area and the rest of your knee is healthy.

The operation aims to relieve pain and restore function so you can stay active. Recent reports show 94% implant survival at 10 years and 90% at 18 years. We will weigh this option with you and decide together whether it suits your knee.

Before the operation

Once surgery is planned, we arrange imaging to map the worn part of your knee. This usually starts with standing X-rays, and sometimes an MRI scan, which shows the cartilage and soft tissues in more detail. These pictures help us plan the operation and confirm this procedure suits your knee.

In the days before surgery, you will get clear instructions from our team. You will need to stop eating and drinking seven hours beforehand. We ask for seven hours so you can be brought forward if the theatre list runs early. Some medications may need to be paused, and we will tell you which ones and when. Bring a list of everything you take, including tablets, drops and supplements. Arrange for someone to drive you home, as you will not be able to drive yourself. Wear loose, comfortable clothing on the day. If you have other medical conditions, you may also need blood tests or a review with the anaesthetist, the doctor who gives the anaesthetic.

On the day

You arrive at the hospital's surgical admissions unit, where you are checked in and prepared for theatre. You meet the anaesthetist, the doctor who gives the anaesthetic. 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.

You wake up in the recovery area, where nurses monitor you while the anaesthetic wears off. Once you are stable, you either go to the ward or go home, depending on the procedure and your recovery. Many people having this operation go home the same day.

What the operation involves

This operation replaces the worn surface in one part of your knee with metal and plastic parts. Your surgeon works through a small cut at the front of the knee, shorter than the cut used for a full knee replacement. Working through this smaller opening disturbs the muscle and tendon straightening your knee far less, which helps you recover sooner.

Inside the knee, your surgeon removes the worn-out joint surfaces in the affected compartment only. The healthy cartilage, ligaments and bone in the rest of your knee are left alone. The metal and plastic parts are then fitted to restore smooth movement between the thigh and shin bones. Special instruments guide their position, and the aim is to line the parts up with a slight undercorrection of the original deformity, so the knee keeps its natural shape. A working anterior cruciate ligament, one of the main straps inside the knee, matters for how the replacement performs over time, and part of the assessment before surgery checks this.

Some practices use a robotic assistant to help plan and carry out the operation. The robot does not perform the surgery itself. It helps your surgeon measure and position the parts precisely, and to reach the planned targets reliably.

The layers of tissue are closed with stitches, and a dressing covers the wound. Many people having this operation go home the same day, as mentioned above. Your knee will be swollen and sore at first, and this settles over the following weeks.

After the operation

You wake up in the recovery area, where nurses watch you as the anaesthetic wears off. Your knee will be sore, and you will be given pain relief to keep you comfortable. The knee will be swollen and covered with a dressing. 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. Most people stand and take a few steps on the day of surgery, with a nurse or physiotherapist close by. Some people go home the same day, and others stay one night. Your team will tell you whether you go home the same day or stay one night in hospital. Please arrange for someone to stay with you for the first 24 hours after you get home.

Recovery

Your knee will be sore and swollen at first. This is normal and settles over the following weeks. Pain relief keeps you comfortable in the early days, and keeping the knee raised when you rest helps the swelling go down. Some people notice the swelling is worse by evening; this usually eases as the days pass.

You will be up and walking on the day of surgery, with help close by. A physiotherapist will guide your exercises, and you will keep doing these at home. The exercises rebuild movement and strength in the knee. You will not wear a brace or cast for this operation. Once the dressing comes off at your review, you can shower normally and get on with light daily tasks around the house. Stairs, short walks and gentle bending of the knee all become part of your routine as comfort allows.

Many people find their knee feels steadier and less painful than before the operation within the first few weeks. Sleep can be restless early on because the knee is tender; finding a comfortable position with a pillow under or between your legs often helps. As the swelling settles and your movement returns, you will manage more on your feet. Driving can come back once you are off strong pain medication and no longer relying on a frame, crutches or a stick for the operated leg, and once you can move your foot between the pedals and brake hard without hesitating and sit and turn comfortably enough to check your mirrors and blind spots. Which knee was replaced matters, and so does whether the car is automatic or manual: in an automatic the right leg does the braking, while in a manual the left leg works the clutch, so a left knee is not the easy case it is often assumed to be. Your own surgeon is the one to decide when you are ready.

Recovery varies from person to person. Your surgeon and physiotherapist will guide your timeline, and most people return to work and low-impact activities within a short timeframe.

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.

Infection is the main concern after any joint replacement. Watch the wound for redness that spreads out from the edges, warmth, oozing fluid or a deep, throbbing pain that does not ease with simple painkillers. You may feel feverish or generally unwell. If you notice any of these signs, call our clinic the same day. If you feel very unwell, go to the emergency department. An infection around a replacement needs prompt treatment, and we will see you quickly to work out the next step.

The artificial parts can loosen or wear over time, or arthritis can develop in the rest of your knee. This usually feels like the old pain coming back, with aching that builds over months rather than days. Some people notice new clicking, grinding or a feeling that the knee is not steady. If this happens, bring it up at your next review. We will examine the knee and arrange imaging. Sometimes the answer is another operation to change the worn part or convert to a full knee replacement, and we will talk that through with you if it comes to that.

The knee can also develop instability, where the joint feels like it gives way or shifts side to side. A plastic spacer inside the knee can occasionally move out of place, which often causes sudden catching or a locked feeling. Tell us promptly if your knee locks, gives way or feels different from day to day.

If you have had keyhole surgery in this knee before your replacement, mention it at review, as it can affect how the replacement performs. Steroid injections into the joint after a replacement raise the risk of infection, so check with us before having one anywhere else.

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

When to call us

Most problems show up in ways you can spot early. Call us if you have a fever, or the wound becomes more red, warm or starts oozing fluid. Call us if you have calf pain or swelling. Go to the emergency department if you suddenly become short of breath or have chest pain, if you feel very unwell, have severe pain that does not ease with painkillers, or cannot feel or move your leg. If your knee locks or gives way, call us promptly.

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

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 [3].
  • The lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction than the medial femoral condyle [3].
  • The tibial articular surface slopes 7° to 10° in the sagittal plane [3].
  • The medial tibial plateau is larger than the lateral plateau and is concave in its frontal and sagittal planes [3].
  • The lateral tibial plateau is smaller and more circular than the medial plateau, concave in the frontal plane and convex in the sagittal plane [3].
  • The patella is the largest sesamoid bone in the body, averaging 2.5 cm in thickness [3].
  • The patella has the thickest articular surface in the body, approximately 5 mm in the midportion and 2 mm on the sides [3].
  • The medial compartment has a large surface area containing a convex femoral condyle and concave tibial plateau [17].
  • The lateral compartment has a smaller surface area than the medial compartment, containing a convex femoral condyle and convex lateral plateau in the sagittal plane [17].
  • The posterior slope of the tibia is a mean of 10.7° in the medial plateau and 7.2° in the lateral plateau [17].

Ligaments

  • The anterior cruciate ligament (ACL) prevents anterior translation and rotation of the tibia on the femur [1].
  • The posterior cruciate ligament (PCL) prevents posterior subluxation of the tibia on the femur [1].
  • The medial collateral ligament stabilizes the knee to valgus stresses [1].
  • The lateral collateral ligament is the main stabilizer against varus stress [1].
  • The ACL is composed of 90% type I collagen and 10% type III collagen [3].
  • The mean length of the ACL is 33 mm and the mean midsubstance width is 11 mm [3].
  • The femoral attachment of the ACL is a semicircular area on the posteromedial aspect of the lateral femoral condyle [3].
  • The tibial attachment of the ACL is a broad, irregular, oval-shaped area slightly medial and anterior to the midline between the tibial spinous processes [3].
  • The anteromedial bundle of the ACL is tight in knee flexion [4].
  • The posterolateral bundle of the ACL is tight in knee extension [4].
  • The PCL resists posterior tibial translation at all degrees of knee flexion [4].
  • The superficial medial collateral ligament resists valgus tibial translation [4].
  • The lateral collateral ligament resists varus tibial translation [4].
  • The popliteofibular ligament is present in 90% of knees [1].

Menisci

  • The menisci are C-shaped fibrocartilaginous disks that provide shock absorption, increase joint congruency, enhance stability, and aid in synovial fluid distribution [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 has a region posterolaterally where it is not firmly attached [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].
  • The lateral meniscus is larger than the medial meniscus and carries a greater share of the lateral compartment pressure [1].
  • The medial meniscus has a semicircular shape covering approximately 50% to 60% of the medial tibial plateau in adulthood [13].
  • The lateral meniscus has a more circular C-shape with symmetric sizes of the anterior and posterior horns [13].
  • The mean lateral meniscus excursion from knee extension to flexion is 11.2 mm, compared to a mean medial meniscus excursion of 5.1 mm [13].
  • Menisci bear one-third to one-half body weight [18].
  • Removal of the meniscus increases contact stresses by up to four times the load transfer to bone [18].

Vascular and Nerve Anatomy

  • The blood supply to the knee is formed from an anastomosis around the knee derived from the descending geniculate, superior geniculate, inferior geniculate, middle geniculate, and anterior tibial recurrent arteries [3].
  • The middle geniculate artery supplies both the anterior and posterior cruciate ligaments [3].
  • 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) [3].
  • The posterior articular branch of the tibial nerve is the largest nerve providing innervation of the intra-articular knee [3].
  • The infrapatellar branch of the saphenous nerve innervates the skin over the region of the anterior knee and proximal tibia [3].

Kinematics and Joint Forces

  • The knee is a hinge joint that incorporates both gliding and rolling, which are essential to its kinematics [4].
  • The "screw-home" mechanism involves the tibia externally rotating 5 degrees in the final 15 degrees of extension [4].
  • Knee joint surface loads are three times body weight during level walking and up to four times body weight with stair walking [18].
  • The ACL is typically subjected to peak loads of 170 N during walking and up to 500 N with running [18].
  • The ultimate strength of the ACL in young patients is about 1750 N [18].
  • Sectioning the PCL increases contact pressures in the medial compartment and the patellofemoral joint [18].
  • The patella bears half the body weight with normal walking and seven times the body weight with squatting and jogging [18].

Investigations

Radiography

  • Plain radiographs are appropriate initial imaging studies for most knee conditions because they allow the assessment of traumatic injury, arthritis, patellofemoral alignment, osteochondral injury, bone neoplasm, and surgical implants [21].
  • Orthogonal views for knee imaging should include at least two perpendicular views: AP and lateral [21].
  • Weight-bearing AP (extension) views are used to assess cartilage loss from the distal femur and tibial plateau [21].
  • Weight-bearing PA (Rosenberg; flexion) views are used to assess cartilage loss from the posterior femur and tibial plateau [21].
  • Patellofemoral views are used to assess patellofemoral alignment (tilt/subluxation), patellar and trochlear morphology, osteochondral injury, and patellofemoral arthritis [21].
  • A notch view is used to assess posterior femoral cartilage, notch width, and osteophytes [21].
  • Radiographs may identify subchondral sclerosis, joint space narrowing, subchondral cysts (variable), osteophytes (variable), and joint subluxation in osteoarthritis [21].
  • Radiographs can underestimate isolated chondral lesions but may demonstrate joint space narrowing, osteophytes, sclerosis, and cysts [25].
  • Weight-bearing AP and lateral views and an axial view of the patellofemoral joint should be reviewed for articular cartilage evaluation [25].
  • The ability to detect subtle narrowing or an isolated chondral defect on the flexion surface may be improved with a semiflexed PA view [25].
  • Long leg alignment views are used to determine the mechanical axis [25].
  • If the mechanical axis traverses the involved compartment (varus knees with medial compartment lesions or valgus knees with lateral compartment lesions), realignment may need to be considered as an initial procedure or as an adjunct to a cartilage restorative procedure [25].
  • Radiographs should be inspected for acute fracture, lateral capsular avulsion (Segond fracture), loose bodies, Pellegrini-Stieda lesion (MCL calcification), and evidence of patellar dislocation in patients with suspected significant knee injury [9].
  • Stress radiographs should be obtained in patients prior to skeletal maturity to rule out an epiphyseal fracture [9].
  • Radiographs are still the standard for initial evaluation of knee arthritis [29].
  • Images for knee arthritis evaluation should include weight-bearing AP and lateral views, a view of the weight-bearing knee flexed at 45-degree angle imaged posterior to anterior, a sunrise view (Merchant view), extension and flexion lateral views, and a standing full-length AP radiograph [29].
  • A standing full-length AP radiograph from hip joint to ankle joint is used to evaluate limb alignment and knee deformity and to identify femoral and/or tibial bone deformity [29].
  • The Kellgren-Lawrence (KL) rating grades extent of OA based on review of AP knee radiograph [29].
  • Primary features used for KL rating include osteophytes (periarticular and tibial spine), joint space narrowing, subchondral sclerosis with or without subchondral cysts, and altered shape of periarticular bones [29].
  • KL Grade 0 indicates normal knee features with no OA [29].
  • KL Grade 1 indicates OA possibly present [29].
  • KL Grade 2 indicates OA present with minimal severity [29].
  • KL Grade 3 indicates OA present with moderate severity [29].
  • KL Grade 4 indicates OA present with severe severity [29].
  • Knee arthroplasty is recommended when Grade 4 findings are present [29].

Magnetic Resonance Imaging (MRI)

  • MRI may help assess overall limb alignment and further delineate intra-articular and extra-articular soft tissues, including cartilage, menisci, ligaments, tendons, muscles, and nerve and vascular structures [21].
  • Increasing strength of the magnetic field (measured in Tesla units) increases the resolution of images [21].
  • An injected contrast agent (intravenous or intra-articular) may help delineate specific tissues of interest in MRI [21].
  • For cruciate ligaments, the presence of edema, intra-articular fluid, disruption of ligament fibers, and an atypical ligament contour may suggest injury on MRI [21].
  • Patterns of meniscal injury can be identified by location (anterior, midbody, posterior, peripheral, articular), pattern (horizontal, longitudinal, radial, complex), and displacement on MRI [21].
  • MRI may identify the degree of articular cartilage injury (chondrosis, full-thickness cartilage loss), the presence of associated bone marrow edema, and the location (medial condyle, lateral condyle, trochlea, patella; anterior, posterior) [21].
  • Edema, avulsion, or discontinuity may be identified for the MCL/lateral collateral ligament (LCL) or associated posteromedial and posterolateral ligamentous complexes on MRI [21].
  • MRI may be used to assess the continuity of the quadriceps or patellar tendon [21].
  • MRI may be used to assess the margin of resection for a neoplasm, identify vascular malformation, or define the location of nerves or vessels relative to popliteal cysts [21].
  • MRI can be used to evaluate articular cartilage morphology [25].
  • MRI is useful for confirming MCL injury and identifying the site of injury [9].
  • MRI is useful to detect the presence of meniscal and other injuries to the knee in the context of MCL injury [9].
  • 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 [9].
  • MRI is often a useful adjunct for diagnosing posterolateral corner and LCL injuries in the severely injured knee [30].
  • MRI findings can refocus the examination to the posterolateral structures when posterolateral injury can often go unnoticed during an initial evaluation [30].
  • MRI is grossly overused in the arthritic patient population [29].
  • If the joint space is significantly narrowed on radiograph, then MRI is not indicated [29].
  • MRI is used when osteonecrosis is suspected in the arthritic patient population [29].

Computed Tomography (CT)

  • CT provides a three-dimensional study performed with ionizing radiation that provides enhanced bone detail [21].
  • Imaging in the axial, sagittal, and coronal planes may help visualize fracture lines and displacement, osteolytic lesions around joint arthroplasty, and cortical disruption in cases of infection or neoplasia [21].
  • Three-dimensional reconstructions may help with preoperative planning for complex intra-articular fractures, multiplanar osteotomy for limb malalignment, and reconstitution of bone loss in joint arthroplasty [21].
  • Axial plane imaging of the hip and knee can help assess the rotational alignment of components of a total knee arthroplasty in cases of patellar maltracking [21].
  • Three-dimensional CT with remodeling is used for preoperative planning for reconstruction associated with dysplasia, post-trauma planning, and complex total knee arthroplasty (TKA) planning [29].

Nuclear Medicine

  • Nuclear medicine involves labeled radionuclide injection followed by delayed imaging of gamma radiation [21].
  • Areas of increased radionuclide concentration appear bright or “hot” in nuclear medicine imaging [21].
  • Nuclear medicine provides a nonspecific study that does not define the etiology of an abnormality but rather the presence of an abnormality that may correlate with a clinical concern [21].
  • Increased radionuclide activity in bone may be a normal postoperative finding for up to 6 to 12 months after a fracture repair or arthroplasty [21].
  • Technetium-99 (Tc-99) is a radionuclide that may help identify infection, neoplasia, occult fracture, bone healing, active phases of heterotopic ossification, implant loosening, or failure of osseointegration [21].
  • Gallium-67 (Ga-67) is a radionuclide that may help differentiate between aseptic and septic prosthetic loosening [21].
  • 24 to 72 hours are needed for a complete Gallium-67 study [21].

Physical Examination

  • The physical examination begins with observation of the patient’s gait [1].
  • The uninjured knee is examined as a basis of comparison with the injured knee [1].
  • Any swelling or effusion should be noted during physical examination [1].
  • A small effusion will cause obliteration of the recesses on the medial and lateral aspects of the patellar tendon [1].
  • With a larger effusion, diffuse swelling is present in the region of the suprapatellar pouch [1].
  • A fluid wave can be palpated on the sides of the patella with a larger effusion [1].
  • Active and then passive range of motion is tested carefully during physical examination [1].
  • The knee is palpated to define areas of localized tenderness [1].
  • The joint lines are located at the level of the inferior pole of the patella when the knee is flexed to 90 degrees [1].
  • Laxity to valgus stresses is assessed by the amount of medial joint space opening that occurs at 30 degrees of flexion for MCL injuries [9].
  • Zero opening is considered normal for valgus stress testing [9].
  • 1–4 mm of medial joint space opening indicates a grade I MCL injury [9].
  • 5–9 mm of medial joint space opening indicates a grade II MCL injury [9].
  • 10–15 mm of medial joint space opening indicates a complete or grade III MCL injury [9].
  • Grade I and II MCL injuries typically have a firm end point to valgus stress [9].
  • A grade III MCL injury tends to have a soft end point to valgus stress [9].
  • The integrity of the LCL is assessed by placing a varus stress, with the knee in full extension and 30 degrees of flexion [30].
  • The average baseline for varus opening is 7 degrees [30].
  • Exam findings with an isolated LCL injury should include varus laxity at 30 degrees of flexion and no instability in full extension [30].
  • The dial test is the most useful test to evaluate for posterolateral instability [30].
  • The dial test is performed at 30 and 90 degrees of flexion with a significant difference being an angle 5 degrees or greater than the contralateral leg [30].
  • Injury to the posterolateral capsule alone is confirmed with greater external rotation at 30 degrees on the dial test [30].
  • An isolated PCL injury is confirmed with greater external rotation at 90 degrees on the dial test [30].
  • Injury to both posterolateral capsule and PCL is confirmed when there is greater rotation at 30 and 90 degrees compared to the uninjured leg on the dial test [30].
  • A careful neurovascular examination should be performed for LCL and/or posterolateral corner injury as the incidence of neurovascular injury, particularly peroneal nerve injury, has been reported in 12–29% of posterolateral knee injuries [30].
  • Patients commonly present with a history of a precipitating traumatic event or previous surgery for articular cartilage defects [25].
  • An effusion, motion deficits, or limb malalignment may be observed in patients with articular cartilage defects [25].
  • Knee stability should be compared with the normal side in patients with articular cartilage defects [25].

References

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

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

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

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

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

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

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

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

[25] Aaos Comprehensive Orthopaedic Review 3. Articular Cartilage Injury and Treatment > IV. Full-­Thickness Outerbridge Grade IV Defects.

[29] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > SECTION 11 KNEE ARTHRITIS ASSESSMENT.

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

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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.