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Periprosthetic joint infection (knee)

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Updated Sep 2026
Illustration: knee

What you're feeling

A periprosthetic joint infection is an infection around a knee replacement. It can start any time after your operation, sometimes months or even years later. The knee is usually painful, swollen and warm. The pain often does not settle the way a normal recovery would, and it may be worse at night or after you have been on your feet.

Everyday tasks can become a struggle. Walking to the letterbox, standing up from a low chair, or getting down the stairs may hurt more than they did before. Some people notice the wound area is tender, or that fluid is leaking from it. A small channel in the skin that weeps fluid, called a sinus tract, is a strong sign of infection and should never be ignored.

The symptoms can be vague. Sometimes the main problem is not obvious pain but a knee that never feels quite right, with stiffness or discomfort that slowly builds. Infection can also make the replacement loose, which causes pain on weight bearing. Because these signs overlap with other knee problems, infection is not always easy to spot.

There is no single test that gives a certain answer. Your surgeon will combine several pieces of information: blood tests, fluid drawn from the knee with a needle, scans, and what they find when they examine you. Some of these tests can be affected by recent antibiotics, so it is important to tell your surgeon if you have taken any. If a late infection is suspected, antibiotics are generally held back until the diagnosis is confirmed or ruled out, because starting them first can hide the bacteria and spoil the samples.

If you have had a knee replacement and your knee is painful, swollen or leaking fluid, contact your surgical team. Early assessment gives you the best chance of a straightforward result.

What's actually happening

A knee replacement is an artificial surface fitted over the ends of your thigh and shin bones. Normally your body accepts it, and the new joint moves smoothly. With a periprosthetic joint infection, bacteria have settled on or around the artificial parts and formed a layer called a biofilm. Think of it as a slimy shield the bacteria build around themselves. Once that shield is in place, your immune system and antibiotics struggle to reach them, which is why the infection can smoulder for months and why treatment usually involves surgery as well as antibiotics.

The infection irritates the tissue around the knee, which is why it becomes painful, swollen and warm. It can also loosen the bond between the artificial parts and your bone, so the replacement no longer sits firmly. That loosening is what makes the knee hurt when you put weight on it, and it explains the fluid or weeping wound some people notice.

This happens in about 1% to 2% of knee replacements. Some situations raise the risk. If you have had a septic arthritis, an infection inside a joint, in the past, you are more likely to develop this problem after a knee replacement than after a hip replacement. Wound problems in the first weeks after surgery also increase the chance of infection reaching deep around the new joint.

There are two broad patterns. An early infection appears soon after the operation, when bacteria are still floating freely and have not yet built their shield. A late or chronic infection develops months or years later, when bacteria are well protected and firmly attached. This difference matters, because early infections can sometimes be treated by washing the joint out and keeping the original replacement in place. Late infections usually need the replacement removed and a new one fitted in separate stages.

What we can do about it

An infection around a knee replacement is not a problem you can manage yourself, and physiotherapy or pain tablets will not clear it. What helps is acting early. If your knee becomes painful, swollen, warm or starts leaking fluid after a knee replacement, contact your surgical team straight away rather than waiting to see if it settles.

Treatment depends on how soon the infection appears after your operation. When infection happens within the first weeks, we can sometimes wash the joint out and clean the artificial parts while leaving your original replacement in place. This is done in an operation, and antibiotics are given afterwards. It works better the earlier it is done. Infection within 1 month of surgery has the highest chance of being cleared this way, and the chance drops as more time passes. For infections within 12 weeks after surgery, this approach is a recognised option.

A later infection usually needs a bigger operation. The infected replacement is removed, an antibiotic spacer is placed in the knee, and antibiotics are given for a period. The spacer is a temporary block that holds the space open and delivers antibiotic medicine locally. Once the infection is under control, a new replacement is fitted in a second operation. This two-stage approach is the usual way to treat an established infection, and an infection-free knee is achieved in about two thirds of cases. Some people with certain health problems face a harder course, and we weigh this up with you when planning treatment.

Choosing treatment is a shared decision. We look at how long ago your replacement was done, which bacteria are involved, your overall health and how unwell the knee is. Then we explain which option suits you and what it involves, and you decide with us how to proceed.

What to expect

The outlook depends a lot on how early the infection is found and treated. When it is caught soon after your operation, washing the joint out and keeping your original replacement can work well. When it is treated this way early, the knee stays free of infection at 1 year in 76% of cases. The earlier this is done, the better the chance it works, and the chance drops as more time passes.

A later infection usually needs the two-stage approach described earlier. An infection-free knee is achieved in about two thirds of cases with this treatment. Some bacteria are harder to clear than others, and infections involving more than one type of bacteria tend to have a harder course. People with other health conditions can also face a tougher road. If the infection does come back after treatment, further surgery is usually needed.

Leaving an infection alone does not work. The bacteria shield themselves in a way your body and antibiotics cannot reach, so the pain, swelling and loosening tend to continue or slowly worsen. The longer it goes on, the harder it becomes to treat.

Recovery after treatment takes time. Many people find their knee moves well once the infection is cleared, and people who have been successfully treated often report their knee feels better than it did before the infection started. But the path is not always smooth. Some people need more than one operation, and a small number need bigger salvage surgery if the infection cannot be cleared any other way.

Your surgical team will keep a close eye on you in the first 2 years after treatment, because this is when infection is most likely to return. If your knee becomes painful, swollen or warm again at any point, contact your team straight away rather than waiting to see if it settles.

When to see someone

An infection around a knee replacement needs to be checked quickly. Contact your surgical team straight away if your knee becomes painful, swollen or warm, or if fluid starts leaking from the wound. Go to an emergency department if you have a fever, feel generally unwell, or the redness and swelling are spreading beyond the knee. Ask for a specialist review if your knee has never felt quite right since the operation, with pain that will not settle, stiffness that keeps building, or discomfort that is worse at night. A small channel in the skin that weeps fluid needs review without delay. If your knee was treated for infection before and the same signs return, contact your team again rather than waiting to see if it settles.

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

Want the clinical detail? Read the clinician version.

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Evidence & references

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

Anatomy & Pathophysiology

Bony Anatomy

  • The bones of the knee are the distal femur, the proximal tibia, and the patella [1].
  • The medial femoral condyle is larger and projects farther posteriorly and distally than the lateral condyle [4].
  • The lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction than the medial femoral condyle [4].
  • The tibial articular surface slopes 7° to 10° in the sagittal plane [4].
  • The medial tibial plateau is larger than the lateral plateau and is concave in its frontal and sagittal planes [4].
  • The lateral tibial plateau is smaller and more circular than the medial plateau, concave in the frontal plane and convex in the sagittal plane [4].
  • The patella is the largest sesamoid bone in the body, averaging 2.5 cm in thickness [4].
  • The patellar articular surface contains a vertical, central ridge that separates the broader lateral facet from the medial facet, and a smaller, more medial facet called the odd facet [4].
  • The posterior slope of the tibia is a mean of 10.7° in the medial plateau and 7.2° in the lateral plateau [9].
  • The fibular head is located a mean of 1.5 cm distal to the joint line, with a range of 6 to 32 mm [9].

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 [4].
  • The mean length of the ACL is 33 mm and the mean midsubstance width is 11 mm [4].
  • The femoral attachment of the ACL is a semicircular area on the posteromedial aspect of the lateral femoral condyle [4].
  • 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 [4].
  • The PCL is the largest of the intra-articular ligaments, with an average length of 38 mm and a mean diameter at the midpoint of 13 mm [17].
  • The PCL has two distinct bundles: an anterolateral (AL) bundle comprising 85% of the cross-sectional area and a posteromedial (PM) bundle [17].
  • The PCL inserts onto a midline depression on the tibia, 10 to 15 mm below the level of the tibial plateaus [17].
  • The meniscofemoral ligaments connect the posterior horn of the lateral meniscus to the intercondylar notch and are thought to be secondary restraints to posterior translation [17].
  • The anteromedial bundle of the ACL is tight in knee flexion and the posterolateral bundle is tight in knee extension [9].
  • The posterolateral bundle of the ACL is responsible for preventing the pivot-shift phenomenon [9].
  • The anterolateral bundle of the PCL is stronger and stiffer than the posteromedial bundle and is tight in knee flexion [9].

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 menisci consist of type I collagen fibers arranged obliquely, radially, and vertically [9].
  • Vascular supply to the menisci is derived from the geniculate arteries, which penetrate into 20% to 30% of the peripheral medial meniscus and 10% to 25% of the peripheral lateral meniscus [9].

Vascular and Nerve Anatomy

  • The blood supply to the knee is formed from an anastomosis around the knee derived from the descending geniculate artery, superior and inferior geniculate arteries, middle geniculate artery, and anterior tibial recurrent arteries [4].
  • The middle geniculate artery supplies both the anterior and posterior cruciate ligaments [4].
  • 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) [4].
  • The posterior articular branch of the tibial nerve is the largest nerve providing innervation of the intra-articular knee [4].
  • The popliteus artery travels through the adductor hiatus, where it is relatively immobile, and distally through the fibrous arch deep to the soleus muscle [14].
  • The common peroneal nerve travels along the posterior edge of the biceps femoris and continues distally around the fibular neck [14].

Kinematics

  • The knee is a hinge joint that incorporates both gliding and rolling, which are essential to its kinematics [5].
  • The "screw-home" mechanism involves the tibia externally rotating 5 degrees in the final 15 degrees of extension [5].
  • The greatest range of motion occurs in the sagittal plane, approximately 160° [21].
  • Knee rotation ranges from 45° in external rotation to 30° in internal rotation [21].
  • In the frontal plane, the range of motion in both abduction and adduction reaches a maximum of 10° [21].
  • During walking, knee range of motion reaches approximately 70° in the sagittal plane, 15° in the frontal plane, and 10° in the transverse plane [21].
  • The normal instant center of the knee joint follows a semicircular path related to the tibiofemoral surface and ligaments crossing the joint [21].
  • Rupture of the cruciate ligaments or disruption of the tibiofemoral surface causes a major change in the path of the instant center, leading to articular dysfunction [21].
  • In full extension, the knee slightly hyperextends with slight tibial external rotation while collateral and cruciate ligaments are tightened to lock the knee [22].
  • The popliteus muscle initiates flexion by pulling the lateral femoral condyle backward while the medial femoral condyle slides forward, resulting in tibial internal rotation [22].

Synovial Anatomy

  • Embryologically, the knee joint forms from three synovial compartments that normally fuse into a single synovial cavity [16].
  • The important synovial plicae of the knee represent unresolved remnants of these partitions and are classified as suprapatellar, infrapatellar, medial patellar, and lateral patellar plicae [16].
  • The medial patellar plica is the most common plica to be of clinical significance, with an incidence reported to range from 10% to more than 50% in normal knees [16].
  • A pathologic medial patellar plica makes firm contact with the underlying femoral condyle at 30 to 40 degrees of flexion [16].
  • In some patients, a median septum separates the posterior aspect of the knee into two compartments, with the posterior cruciate ligament projecting anteriorly in the septum [19].

Investigations

Plain Radiography

  • Plain radiographs are appropriate initial imaging studies for most knee conditions, allowing assessment of traumatic injury, arthritis, patellofemoral alignment, osteochondral injury, bone neoplasm, and surgical implants [3].
  • Standard knee imaging includes anterior-posterior (AP), lateral, and axial views (skyline, sunrise, sunset) [27].
  • Supine AP knee radiographs do not adequately estimate joint space width needed to estimate the degree of osteoarthritis progression [27].
  • A 45° standing flexion view was introduced to better evaluate joint space because plain frontal radiographs may not accurately display actual joint space due to cartilage wear patterns, meniscal integrity, or tibial slope variances [27].
  • The fixed flexion view (FFV) is a technique with improved reproducibility for evaluating joint space, involving a 10° caudal irradiation angle and specific limb positioning [27].
  • The Lyon Schuss view (LSV) uses fluoroscopic adjustment of the irradiation angle relative to the medial tibial plateau, which is more accurate for measuring actual joint space width but involves higher radiation exposure and more complex positioning [27].
  • Goniometer readings of long limb alignment or measured on a fixed flexion view correlate well with angles measured on long limb radiographs, providing an alternative if long limb radiographs are not available [27].
  • Radiographs are the standard for initial evaluation of knee pain, including weight-bearing AP and lateral views, a 45-degree flexion PA view, sunrise view, extension and flexion lateral views, and standing full-length AP radiograph [23].
  • The Kellgren-Lawrence (KL) classification grades osteoarthritis severity from 0 to 4 based on AP knee radiographs, using features such as osteophytes, joint space narrowing, subchondral sclerosis, and bone shape alterations [23].
  • Knee arthroplasty is recommended when KL Grade 4 findings are present [23].
  • Radiographic studies help confirm the clinical diagnosis of a joint disorder determined using history and physical examination [3].

Computed Tomography (CT)

  • CT provides enhanced bone detail through three-dimensional imaging with ionizing radiation [3].
  • CT imaging in axial, sagittal, and coronal planes helps visualize fracture lines, displacement, osteolytic lesions around joint arthroplasty, and cortical disruption in cases of infection or neoplasia [3].
  • Three-dimensional CT reconstructions assist in preoperative planning for complex intra-articular fractures, multiplanar osteotomy for limb malalignment, and reconstitution of bone loss in joint arthroplasty [3].
  • Axial plane CT imaging of the knee helps assess the rotational alignment of components in total knee arthroplasty in cases of patellar maltracking [3].
  • Three-dimensional CT with remodeling is used for preoperative planning for reconstruction associated with dysplasia, post-trauma planning, and complex total knee arthroplasty planning [23].

Magnetic Resonance Imaging (MRI)

  • MRI is the most useful study for differentiating osteonecrosis from other conditions such as osteochondritis dissecans, transient osteoporosis, bone bruises, or occult fractures [29].
  • A serpentine lesion within a well-demarcated border is a specific finding on MRI for osteonecrosis [29].
  • Bone edema on MRI is a common feature of osteoarthritis, osteonecrosis, cartilage injury, and transient regional osteoporosis [29].
  • MRI may identify the degree of articular cartilage injury, including chondrosis and full-thickness cartilage loss, as well as associated bone marrow edema and location [3].
  • MRI can identify patterns of meniscal injury by location, pattern (horizontal, longitudinal, radial, complex), and displacement [3].
  • MRI may suggest cruciate ligament injury through the presence of edema, intra-articular fluid, disruption of ligament fibers, and atypical ligament contour [3].
  • MRI is used to assess the continuity of the quadriceps or patellar tendon [3].
  • 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 [3].
  • MRI is grossly overused in the arthritic patient population and is not indicated if the joint space is significantly narrowed on radiograph [23].
  • MRI is indicated when osteonecrosis is suspected in the arthritic patient population [23].
  • A systematic review quantified the diagnostic accuracy of MRI for detection of meniscal injury and ACL tear [20].
  • Compositional MRI techniques, including T1ρ, T2*, dGEMRIC, and gagCEST, are used for early recognition of cartilage degeneration [20].

Nuclear Medicine

  • Nuclear medicine involves labeled radionuclide injection followed by delayed imaging of gamma radiation, where areas of increased concentration appear bright or "hot" [3].
  • Nuclear medicine provides a nonspecific study that indicates the presence of an abnormality but does not define its etiology [3].
  • Increased radionuclide activity in bone may be a normal postoperative finding for up to 6 to 12 months after fracture repair or arthroplasty [3].
  • 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 [3].
  • Gallium-67 (Ga-67) is a radionuclide that may help differentiate between aseptic and septic prosthetic loosening, requiring 24 to 72 hours for a complete study [3].

General Assessment

  • Assessment of the knee joint must combine physical examination with radiographic (including full-length alignment views) and MRI findings [30].
  • Radiographic evaluations are essential when diagnosing osteochondritis dissecans (OCD) lesions of the knee, though important aspects may be better seen with MRI [26].
  • Physical examination along with radiographic or advanced imaging findings must be used concomitantly to determine the source of symptoms and appropriate surgical intervention [7].

References

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

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

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

[5] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > SECTION 1 KNEE > ANATOMY (FIG. 4.1).

[7] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Arthroscopy and Preservation, Knee Reconstruction > Introduction.

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

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

[16] Campbell S Operative Orthopaedics 4 Volume Set. TRANSTIBIAL PULL-OUT REPAIR OF RADIAL OR MENISCAL ROOT TEAR > SYNOVIAL PLICAE OF THE KNEE.

[17] Rockwood And Green S Fractures In Adults. 59: Patellar Fractures and Dislocations and Extensor Mechanism Injuries > Posterior Knee Anatomy.

[19] Campbell S Operative Orthopaedics 4 Volume Set. SINGLE-INCISION POSTEROLATERAL APPROACH TO THE LATERAL AND POSTERIOR MALLEOLI > POSTEROLATERAL AND POSTEROMEDIAL APPROACHES TO THE KNEE.

[20] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Arthroscopy and Preservation, Knee Reconstruction > Annotated References.

[21] Aaos Comprehensive Orthopaedic Review 3. Biomechanics and Wear in Joint Arthroplasty > III. The Knee Joint.

[22] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Anatomy > Knee Kinematics.

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

[26] Orthopaedic Knowledge Update. Osteochondritis Dissecans of the Knee and Elbow* > Summary.

[27] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Anatomy > Imaging (Radiograph, MRI, CT Scan, Dynamic Versus Static) > Radiograph.

[29] Aaos Comprehensive Orthopaedic Review 3. General Evaluation of the Knee Patient > III. Osteonecrosis.

[30] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Arthroscopy and Preservation, Knee Reconstruction > Summary.

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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.