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Patients › Knee

胫骨高位截骨术

Updated Sep 2026
Illustration: knee

本页面由机器翻译,尚未经临床医生审核。英文版本为权威版本。

为何建议进行此手术

该手术涉及对小腿主要骨骼——胫骨进行切割和重塑,以使您的体重从膝关节磨损部位转移开。我们通常建议年龄较轻且活动量较大(通常 60 岁以下)的人群进行此手术,特别是那些膝关节仅部分区域而非整个关节存在关节炎的患者。该手术适合从事体力劳动或希望继续参与体育运动的人群。

手术的目的是缓解疼痛,让您在保留自身膝关节的同时保持活动能力。该手术在 5 年时的存活率超过 96%。我们将与您讨论该手术是否适合您,并共同做出决定。

术前准备

一旦决定进行手术,我们会仔细制定手术计划。您需要拍摄站立位X光片,有时还需要进行磁共振成像(MRI)扫描,该检查利用磁场显示膝关节的软组织。这些影像可显示磨损软骨的位置,帮助我们精确确定骨骼重塑的程度。大多数患者无需其他检查。如果您有其他基础疾病,可能需要进行血液检查或由麻醉师(负责实施麻醉的医生)进行评估。在手术前的几天内,我们会告知您需要停用哪些药物以及停用的时间。手术前7小时内请勿进食或饮水;我们要求禁食时间略长于常规,以便如果手术排程提前,您的手术时间可以相应提前。请安排他人驾车送您回家,并穿着宽松舒适的衣物。

手术当天

您抵达医院的手术入院单元,在此办理入院手续并进行术前准备。您将见到麻醉师,即负责让您进入睡眠状态的医生。本手术在全身麻醉下进行。有时会追加区域神经阻滞以缓解术后疼痛;麻醉师将在当天就此与您讨论。随后,您将被带入手术室,手术在此进行。

您将在复苏区醒来,护士会在此看护您,直至麻醉药效消退。一旦您的生命体征稳定,根据手术类型及您的恢复情况,您将被转入病房或直接回家。

手术内容

手术通过膝关节内侧、胫骨上部的切口进行,胫骨是下肢的主要骨骼。外科医生将大部分切开该骨骼,然后轻轻撑开切口,从而改变膝关节下方骨骼的角度。这会将您的体重转移到关节中更健康、磨损较少的侧面上。

一旦骨骼处于预定位置,带有螺钉的金属板将固定骨骼直至其愈合。金属板保留在您的膝关节内。在某些情况下,它后来会通过同一区域取出,这可以缓解部分患者的症状。随后,切口被缝合并用敷料覆盖。

这一切的目的是减轻膝关节磨损部分的负荷,这正是缓解疼痛的原因。外科医生在手术前会根据您的站立位X光片仔细规划矫正方案,以确保骨骼被精确地打开至为您腿部计算出的量。

术后

您将在复苏病房醒来,护士会在此监护您直至麻醉消退。您的膝关节将覆盖敷料,随着麻木感消退,您可能会感到一些疼痛。护士会为您用药以缓解不适。物理治疗师可能会在手术当天或次日早晨协助您使用拐杖站立并行走几步。回家后,前24小时内应有人陪伴您。您的医疗团队会告知您是当天回家还是在医院过夜。我们会保留敷料约10天;除非我们告知您,否则请勿在此之前拆除。我们会在复诊时为您更换或拆除敷料。

恢复

最初几天以舒适为主。您的膝盖会疼痛、肿胀,切口附近的皮肤可能会感觉紧绷。止痛药有助于控制疼痛,抬高腿部休息有助于减轻肿胀。有些人最初会注意到肿胀在傍晚时更为明显。用毛巾包裹冰袋敷敷可以缓解这种情况。

起初您需要使用拐杖行走,在骨骼愈合期间,仅将部分体重通过腿部传递。物理治疗师将指导您的锻炼。这些锻炼从轻柔的动作开始,活动膝盖并保持大腿肌肉工作,然后随着骨骼愈合逐渐加强。敷料大约保留10天;我们在复诊时会更换或拆除敷料。

在日常生活中,您在一段时间内需要他人协助上下楼梯和购物。您可以在屋内活动,抬高腿部休息,并每天多次进行锻炼。通常仰卧并支撑腿部是最舒适的睡姿。一旦我们告知可以拆除敷料,您就可以淋浴了。

恢复的关键节点取决于事件,而非具体日期。一旦骨骼愈合到足以承受完全体重,行走会变得更加稳定,拐杖会逐渐停用。随着力量恢复,您可以开始更长的步行,然后根据膝盖状况返回工作和运动。大多数人恢复到与术前相同或更好的运动水平。

每个人的恢复情况各不相同。您的外科医生和物理治疗师将指导您的恢复时间表。

可能出现的问题

大多数患者恢复良好,但偶尔也可能出现问题。您的外科医生和医疗团队会密切监测您,以便尽早发现任何问题。

骨骼可能愈合缓慢,或在极少数情况下完全无法愈合。您可能会注意到切口部位出现持续不缓解的疼痛,或感觉膝关节不稳。如果发生这种情况,请在下次复诊时告知医生。

金属内固定板有时可能会引起不适。这通常表现为内固定板区域的酸痛或压痛,尤其在寒冷天气或活动后更为明显。如果这让您感到困扰,日后可以通过同一区域的小切口将内固定板取出。请在复诊时提及此情况。

感染并不常见,但有可能发生。请留意伤口周围发红扩散、局部发热、肿胀加重而非减轻,或切口有液体渗出。您可能会感到发热。如果发现上述任何症状,请立即致电诊所。

腿部深静脉可能形成血栓。这表现为小腿突然肿胀和压痛,有时皮肤感觉发热。如果发现这种情况,请在当天联系诊所。如果您出现呼吸困难或胸痛,请前往急诊科。

膝关节附近的神经可能在手术过程中受到挫伤。这可能表现为足部或脚趾麻木、刺痛或无力,或抬脚困难。其中许多症状会自行缓解。如果您注意到这些情况,请在下次复诊时告知您的外科医生。

矫正后的骨骼在极少数情况下可能滑回原来的位置。您可能会注意到膝关节逐渐再次感觉错位,或磨损侧疼痛复发。请在复诊时提及此情况。

其他问题可能包括手术过程中发生骨折、膝关节僵硬,或一种罕见的疼痛状况,该状况会导致在正常愈合期之后出现烧灼感、敏感性和肿胀。您的医疗团队会及时发现这些问题并与您共同管理。

本页上的并发症表格列出了典型发生率,如果您想了解具体数据,可查阅该表。

何时联系我们

大多数问题会在早期出现,我们更希望尽早得知。如果您出现发热、伤口周围发红范围扩大,或切口有液体渗出,请致电我们。如果您的小腿突然肿胀且触痛,请在当天联系我们。如果您出现呼吸困难或胸痛,请立即前往急诊。如果您腿部或足部失去感觉,或无法活动,请立即前往急诊。如果疼痛突然明显加重,或肿胀在最初几天后持续增大,请致电我们。


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

Complications and Pathology

  • Recurrence of varus deformity is reported to occur in 5% to 30% of patients with proximal tibial osteotomy [1].
  • Recurrence of varus deformity was the most common complication in Coventry's report of 213 proximal tibial osteotomies [1].
  • Coventry attributed the recurrence of varus deformity to inadequate correction at the time of surgery [1].
  • Overcorrection beyond the normal 5 degrees of anatomic valgus decreased the frequency of recurrent varus deformity [1].
  • Peroneal nerve injury is most often related to fibular osteotomy performed in conjunction with proximal tibial osteotomy [1].
  • The peroneal nerve is most at risk during osteotomy of the proximal fibula, where the nerve wraps around the neck of the fibula before dividing into deep and superficial branches [1].
  • Popliteal artery injury is rare but devastating [1].
  • At 90 degrees of flexion, the distance between the osteotomy blade and the popliteal artery averaged 10.6 mm in a cadaver study [1].
  • Most patients develop significant patella baja after proximal tibial osteotomy [1].
  • Shortening of the patellar tendon after prolonged immobilization is a factor that may cause patella baja [1].
  • New bone formation at the site of the osteotomy in the area of the insertion of the patellar tendon is a factor that may cause patella baja [1].
  • Fibrosis of the patellar tendon is a factor that may cause patella baja [1].
  • The decrease in the height of the patella has no appreciable effect on the success or failure of the osteotomy or the need for subsequent total joint replacement [1].
  • Patella baja is likely to make a subsequent total knee arthroplasty more technically demanding [1].

Comparative Outcomes

  • A meta-analysis by Fu et al. showed better knee function in the arthroplasty group compared to high tibial osteotomy [1].
  • A meta-analysis by Fu et al. showed no difference in knee score between the arthroplasty group and high tibial osteotomy [1].
  • The 10-year survival rate for medial compartment arthroplasty reported by Pandit et al. was 91% [1].
  • The 10-year survival rate for high tibial osteotomy was 60% [1].
  • Unicompartamental arthroplasty is less stressful for the patient than total knee arthroplasty [1].
  • Unicompartamental arthroplasty is more likely to be “forgotten” by the patient according to Zuiderbaan et al. [1].
  • Patients with the varus morphotype may be better served with an osteotomy to unload the already overloaded medial compartment according to Becker and Hirschmann [1].
  • Osteotomy may be preferred if the underlying cause is significant malalignment [1].
  • Unicompartamental arthroplasty may be best suited for true medial compartment arthritis [1].
  • Total knee arthroplasty may be the best choice if the problem is an undiagnosed early inflammatory arthritis [1].

Investigations

Radiographic Evaluation

  • 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 [7].
  • Orthogonal views for knee imaging should include at least two perpendicular views: AP and lateral [7].
  • Weight-bearing AP (extension) views are used to assess cartilage loss from the distal femur and tibial plateau [7].
  • Weight-bearing PA (Rosenberg; flexion) views are used to assess cartilage loss from the posterior femur and tibial plateau [7].
  • Patellofemoral views are used to assess patellofemoral alignment (tilt/subluxation), patellar and trochlear morphology, osteochondral injury, and patellofemoral arthritis [7].
  • A notch view is used to assess posterior femoral cartilage, notch width, and osteophytes [7].
  • Radiographs may identify subchondral sclerosis, joint space narrowing, subchondral cysts (variable), osteophytes (variable), and joint subluxation in osteoarthritis [7].
  • Radiographs may identify joint space loss and peripheral bone erosion in inflammatory arthropathy [7].
  • Radiographs may identify subchondral radiolucency, most common in the medial femoral condyle, in osteochondral defects [7].
  • Radiographs may identify linear radiolucency or radiodensity, most common in the proximal medial tibia, in stress fractures [7].
  • Radiographs may identify a mixed sclerotic pattern with a subchondral, epiphyseal, or metaphyseal location in osteonecrosis [7].
  • Radiographs may identify malalignment, osteophytes, cysts, and joint space loss in patellofemoral disease [7].
  • Radiographs can underestimate isolated chondral lesions but may demonstrate joint space narrowing, osteophytes, sclerosis, and cysts [9].
  • Weight-bearing AP and lateral views and an axial view of the patellofemoral joint should be reviewed for articular cartilage evaluation [9].
  • The ability to detect subtle narrowing or an isolated chondral defect on the flexion surface may be improved with a semiflexed PA view [9].
  • Long leg alignment views are used to determine the mechanical axis [9].
  • 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 [9].
  • Radiographs are still the standard for initial evaluation of knee arthritis [13].
  • Images for knee arthritis evaluation should include weight-bearing AP and lateral views [13].
  • Images for knee arthritis evaluation should include a view of the weight-bearing knee flexed at 45-degree angle, imaged posterior to anterior [13].
  • Images for knee arthritis evaluation should include a sunrise view (i.e., Merchant view) [13].
  • Images for knee arthritis evaluation should include extension and flexion lateral views [13].
  • A standing full-length AP radiograph from hip joint to ankle joint is used to evaluate limb alignment and knee deformity [13].
  • A standing full-length AP radiograph is used to identify femoral and/or tibial bone deformity (developmental or traumatic) [13].
  • The KL rating grades extent of OA based on review of AP knee radiograph [13].
  • Primary features used for KL rating include osteophytes (periarticular and tibial spine) and joint space narrowing [13].
  • KL Grade 0 indicates normal knee features with no OA [13].
  • KL Grade 1 indicates OA possibly present [13].
  • KL Grade 2 indicates OA present with minimal severity [13].
  • KL Grade 3 indicates OA present with moderate severity [13].
  • KL Grade 4 indicates OA present with severe severity [13].
  • Knee arthroplasty is recommended when Grade 4 findings are present [13].

Computed Tomography

  • Three-dimensional CT study provides enhanced bone detail [7].
  • 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 [7].
  • 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 [7].
  • 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 [7].
  • 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 [13].

Magnetic Resonance Imaging

  • Increasing strength of the magnetic field (measured in Tesla units) increases the resolution of images [7].
  • An injected contrast agent (intravenous or intra-articular) may help delineate specific tissues of interest in MRI [7].
  • MRI may identify the presence of edema, intra-articular fluid, disruption of ligament fibers, and an atypical ligament contour to suggest cruciate ligament injury [7].
  • MRI can identify patterns of meniscal injury by location (anterior, midbody, posterior, peripheral, articular), pattern (horizontal, longitudinal, radial, complex), and displacement [7].
  • 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) [7].
  • MRI may identify edema, avulsion, or discontinuity for the MCL/lateral collateral ligament (LCL) or associated posteromedial and posterolateral ligamentous complexes [7].
  • MRI may be used to assess the continuity of the quadriceps or patellar tendon [7].
  • 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 [7].
  • MRI can be used to evaluate articular cartilage morphology [9].
  • MRI is grossly overused in the arthritic patient population [13].
  • If the joint space is significantly narrowed on radiograph, then MRI is not indicated [13].
  • MRI is used when osteonecrosis is suspected [13].
  • MRI can be helpful in confirming MCL diagnosis and helping to rule out concomitant meniscal injury [3].
  • MRI is useful for confirming MCL injury and identifying the site of injury [3].
  • MRI is useful to detect the presence of meniscal and other injuries to the knee [3].
  • 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 [3].
  • MRI should be obtained as a useful adjunct to help diagnose posterolateral corner injuries in LCL injuries [14].
  • MRI is often a useful adjunct for diagnosing posterolateral corner and LCL injuries in the severely injured knee [14].
  • MRI findings can refocus the examination to the posterolateral structures when posterolateral injury can often go unnoticed during an initial evaluation [14].
  • MRI can prove to be an extremely valuable adjunct in diagnosis when pain and guarding at the time of injury can often obscure posterolateral injury [14].

Nuclear Medicine

  • Nuclear medicine involves labeled radionuclide injection followed by delayed imaging of gamma radiation [7].
  • Areas of increased radionuclide concentration appear bright or “hot” in nuclear medicine imaging [7].
  • 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 [7].
  • Increased radionuclide activity in bone may be a normal postoperative finding for up to 6 to 12 months after a fracture repair or arthroplasty [7].
  • 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 [7].
  • Gallium-67 (Ga-67) is a radionuclide that may help differentiate between aseptic and septic prosthetic loosening [7].
  • 24 to 72 hours are needed for a complete Gallium-67 (Ga-67) study [7].

Physical Examination

  • Physical examination along with radiographic or advanced imaging findings must be used concomitantly to determine the source of each patient’s symptoms and to determine appropriate surgical intervention when nonsurgical measures have failed [2].
  • The physical examination for knee injury begins with observation of the patient’s gait [5].
  • The uninjured knee is examined as a basis of comparison with the injured knee [5].
  • Any swelling or effusion should be noted during physical examination [5].
  • A small effusion will cause obliteration of the recesses on the medial and lateral aspects of the patellar tendon [5].
  • With a larger effusion, diffuse swelling is present in the region of the suprapatellar pouch [5].
  • A fluid wave can be palpated on the sides of the patella with a larger effusion [5].
  • Active and then passive range of motion is tested carefully during physical examination [5].
  • The knee is palpated to define areas of localized tenderness [5].
  • The joint lines are located at the level of the inferior pole of the patella when the knee is flexed to 90 degrees [5].
  • To determine varus and valgus stability, the patient’s foot is held between the examiner’s elbow and hip [5].
  • Medial knee pain and instability at 30 degrees of flexion is diagnostic for MCL injury [3].
  • Laxity to valgus stresses is assessed by the amount of medial joint space opening that occurs at 30 degrees of flexion [3].
  • It is important to stress the knee at 30 degrees of flexion because with the knee in full extension the posterior capsule and PCL will stabilize the knee to valgus stress [3].
  • Zero opening is considered normal for MCL injury grading [3].
  • 1–4 mm of medial joint space opening indicates a grade I MCL injury [3].
  • 5–9 mm of medial joint space opening indicates a grade II MCL injury [3].
  • 10–15 mm of medial joint space opening indicates a complete or grade III MCL injury [3].
  • Grade I and II MCL injuries typically have a firm end point to valgus stress [3].
  • A grade III MCL injury tends to have a soft end point to valgus stress [3].
  • Varus stress to the knee with opening at 30 degrees of flexion is diagnostic for an isolated LCL injury [14].
  • The integrity of the LCL is assessed by placing a varus stress, with the knee in full extension and 30 degrees of flexion [14].
  • Baseline varus opening is widely variable and should be compared to the contralateral leg [14].
  • The average baseline for varus opening is 7 degrees [14].
  • Exam findings with an isolated LCL injury should include varus laxity at 30 degrees of flexion and no instability in full extension [14].
  • The dial test is the most useful test to evaluate for posterolateral instability [14].
  • 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 [14].
  • Injury to the posterolateral capsule alone is confirmed with greater external rotation at 30 degrees [14].
  • An isolated PCL injury is confirmed with greater external rotation at 90 degrees [14].
  • Injury to both posterolateral capsule and PCL is confirmed when there is greater rotation at 30 and 90 degrees compared to the uninjured leg [14].
  • Patients commonly present with a history of a precipitating traumatic event or previous surgery for articular cartilage defects [9].
  • An effusion, motion deficits, or limb malalignment may be observed in patients with articular cartilage defects [9].
  • Knee stability should be compared with the normal side in patients with articular cartilage defects [9].
  • Pain with weight bearing is a clinical presentation of knee arthritis [13].
  • Pain with weight bearing is aggravated by stairs, inclines, and transition from sit to stand [13].
  • Bowing deformity and instability are seen later in the clinical presentation of knee arthritis [13].
  • Knee thrust is seen later in the clinical presentation of knee arthritis [13].
  • A varus thrust indicates ligament stretch-out on the convex side of the thrust [13].
  • A varus thrust overloads the medial compartment [13].
  • A varus thrust accelerates cartilage degeneration in the medial compartment [13].
  • A valgus thrust overloads the lateral compartment [13].
  • A valgus thrust accelerates cartilage degeneration in the lateral compartment [13].

Complications

General Complications

  • Reported complications of proximal tibial osteotomy include recurrence of deformity, peroneal nerve palsy, nonunion, infection, knee stiffness or instability, intraarticular fracture, deep vein thrombosis, compartment syndrome, patella infra, and osteonecrosis of the proximal fragment [1].
  • Inadequate correction and recurrent varus deformity have been reported to occur in 5% to 30% of patients with proximal tibial osteotomy [1].
  • Recurrence of a varus deformity was the most common complication in Coventry's report of 213 proximal tibial osteotomies [1].
  • Coventry suggested that overcorrection beyond the normal 5 degrees of anatomic valgus decreased the frequency of recurrent varus deformity [1].

Neurovascular Injury

  • The peroneal nerve is most at risk with osteotomy of the proximal fibula, where the nerve wraps around the neck of the fibula before dividing into deep and superficial branches [1].
  • A cadaver study demonstrated that at 90 degrees of flexion, the distance between the osteotomy blade and the popliteal artery averaged only 10.6 mm [1].
  • Authors of a cadaver study recommended keeping something substantial between the proximal tibia and the popliteal artery, especially when using an oscillating power saw [1].

Patellar Position

  • Factors that may cause patella baja include shortening of the patellar tendon after prolonged immobilization, new bone formation at the site of the osteotomy in the area of the insertion of the patellar tendon, and fibrosis of the patellar tendon [1].

References

[1] Campbell S Operative Orthopaedics 4 Volume Set. SOFT-TISSUE PROCEDURES AND OSTEOTOMIES ABOUT THE KNEE > GENERAL COMPLICATIONS OF HIGH TIBIAL OSTEOTOMY.

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

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

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

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

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

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

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

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Using Creative Commons Public Licenses

Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.

Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees


Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.


Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.