Skip to content

Osteoarthritis Management

Degenerative knee joint disease: non-surgical management, intra-articular injection options, and indications for total knee replacement.

Overview

Osteoarthritis of the knee is a heterogeneous condition requiring tailored surgical management. The American Academy of Orthopaedic Surgeons (AAOS) developed Appropriate Use Criteria to help determine the appropriateness of treatments by synthesizing evidence-based information with clinical expertise [8]. These criteria were established by a voting panel reviewing 864 scenarios to assist in decision-making for the heterogeneous patient population routinely seen in practice [4, 9]. Treatments are categorized as Appropriate, May Be Appropriate, or Rarely Appropriate based on specific clinical scenarios [4]. Additionally, the AAOS Clinical Practice Guideline Summary provides 16 recommendations and seven options based on a systematic review of over 1,500 full-text articles [3].

The Surgical Management of Osteoarthritis of the Knee evidence-based guideline contains 38 recommendations for improving surgical treatment based on current best evidence [5]. Of these, 14 are classified as Strong, 14 as Moderate, and 10 as Limited [5]. Despite these guidelines, most chronic knee pain is managed with medication despite concerns about safety, efficacy, and cost, management guideline recommendations, and patient preferences [7]. Management of moderate to severe knee OA often does not align with AAOS guidelines [10].

Optimal management of cartilage defects remains controversial [34]. There appears to be evidence justifying the use of biologic therapies for knee osteoarthritis management, though more high-level, larger human studies utilizing standardized protocols are needed [2]. Further studies are required to increase the limited evidence on non-surgical treatments and their combination, to optimize indications, application modalities, and results with particular focus on early OA [15]. Orthopaedic surgeons must critically analyze literature and improve treatment efficacy to counter guidelines that limit patient access to care based on flawed analyses [37]. Surgeons should also promote innovative modalities like meniscal repair to ameliorate disability associated with osteoarthritis of the knee [37]. Future rigorous research methods could minimize common biases in clinical knee cartilage research through strict study design and patient selection criteria, larger patient enrollment, more extended follow-up, and standardization of clinical treatment pathways [34].

Anatomy & Pathophysiology

General Pathophysiology and Biomechanics

Accelerated knee osteoarthritis is distinct from typical knee osteoarthritis [11]. The pathogenesis is initiated by changes in the physiological state of chondrocytes [61]. In osteoarthritis gait, the combination of altered stance phase loading and reduced walking speed may disrupt biphasic lubrication mechanisms, contributing to increased friction in degenerated articular cartilage [63]. However, friction of cadaveric knee joint tissues does not increase with progressing degeneration [69].

Current biomechanical evidence suggests that unloading of the affected knee compartment does not significantly hinder disease progression [43]. Knee biomechanical markers are associated with patient-reported knee function to a greater extent than X-ray grading [35]. Radiographic severity and biomechanical markers provide complementary information in the assessment of osteoarthritis patients [35]. Personalized biomechanical treatment can improve gait patterns, pain, function, and quality of life [68].

Patellofemoral Joint

Recurrent patellofemoral instability causes cartilage degeneration [60]. Surgical restoration of the anatomy and biomechanics of the patellofemoral joint may significantly reduce the risk of osteoarthritis resulting from patellofemoral instability [60]. Conversely, nonanatomic surgery and surgical over-constraint may also cause osteoarthritis [60]. Patellofemoral kinematics and retropatellar pressure change after total knee arthroplasty (TKA) in different manners depending on the type of TKA used [47].

Ligamentous and Osseous Alignment

Limited excursion of the quadriceps muscle is the main limiting factor to knee flexion in the arthritic knee [72]. Both proximal and distal tibial tubercle osteotomies can significantly correct knee varus deformity and improve knee function [70]. Early knee function scores are similar between proximal and distal tibial tubercle osteotomies [70].

Preoperative quantitative pivot shift does not correlate with in vivo kinematics following ACL reconstruction with or without lateral extraarticular tenodesis [71]. Preoperative quantitative pivot shift correlates with healthy in vivo knee kinematics in the contralateral extremity [71]. Bioenhanced anterior cruciate ligament (ACL) repair produces a ligament that is biomechanically similar to an ACL graft [65]. Bioenhanced ACL repair provides chondroprotection to the joint after ACL surgery [65].

Interventions and Outcomes

There was no change in sagittal plane knee moment, including flexion and extension moments, from before to after medial open wedge high tibial osteotomy [74]. Evidence of improvement in knee functions following intra-articular injection of mesenchymal stem cells after high tibial osteotomy remains limited [73]. Platelet-rich plasma (PRP) did not confer superiority when assessing knee-related structural changes in the treatment of knee osteoarthritis [75].

The VER-brace obtained more effectiveness than foot orthoses (FO) on pain and knee adduction moment (KAM) after 3 months for medial knee osteoarthritis [76]. Combined treatment with braces and foot orthoses did not substantially improve biomechanical and functional outcomes compared to single modalities [76].

Classification

AAOS Appropriate Use Criteria: The American Academy of Orthopaedic Surgeons developed these criteria to determine the appropriateness of treatments for osteoarthritis of the knee by synthesizing evidence-based information with clinical expertise [8]. A voting panel reviewed 864 scenarios to categorize treatments as Appropriate, May Be Appropriate, or Rarely Appropriate [4]. This effort aimed to help determine the appropriateness of treatments for a heterogeneous patient population [9].

AAOS Clinical Practice Guideline: The Surgical Management of Osteoarthritis of the Knee Evidence-based Guideline contains 38 recommendations for improving surgical treatment [5]. Of these, 14 are classified as Strong, 14 as Moderate, and 10 as Limited [5]. The AAOS Clinical Practice Guideline Summary provides 16 recommendations and seven options based on a systematic review of over 1,500 full-text articles [3].

Malaysian Delphi Consensus: This consensus presents nine recommendations that advocate an algorithmic approach in the management of patients living with knee OA [13].

Early Osteoarthritis Definitions: The paper on Early osteoarthritis of the knee provides an updated review of the current status of the diagnosis and definition of early knee OA, including clinical, radiographical, histological, MRI, and arthroscopic definitions and biomarkers [14]. It presents practical classification criteria for early knee OA based on current evidence [14]. The effort of the ESSKA Cartilage Committee in defining early OA may lead to an improvement in the current treatment algorithm [42].

Other Considerations: Failure definitions of cartilage treatments differ in scientific articles, generating confusion and heterogeneous data [44]. Understanding subchondral vascular physiology will be key to better MRI classification of osteoarthritis [26].

Clinical Presentation

Osteoarthritis of the knee represents a heterogeneous patient population routinely encountered in clinical practice [9]. Accelerated knee osteoarthritis is distinct from typical knee osteoarthritis [11]. Radiographic findings serve as an imprecise guide for the likelihood of presenting knee pain or disability [19], resulting in significant discordance between clinical and radiographic diagnoses [19]. While many OA-related biomarkers are currently available, none can be considered a surrogate marker of clinical and imaging features for the diagnosis or prognosis of the disease at this time [21].

The diagnosis and definition of early knee osteoarthritis encompass clinical, radiographical, histological, MRI, and arthroscopic definitions alongside biomarkers [14]. Practical classification criteria for early knee osteoarthritis are based on current evidence [14].

Most chronic knee pain is managed with medication despite concerns regarding safety, efficacy, cost, management guideline recommendations, and patient preferences [7]. Management of moderate to severe knee osteoarthritis often does not align with AAOS guidelines [10]. Furthermore, there is specialty-related variability in some aspects of knee osteoarthritis management between general practitioners and rheumatologists [23].

Investigations

AAOS Guidelines: The AAOS Appropriate Use Criteria for Surgical Management of Osteoarthritis of the Knee categorize treatments as Appropriate, May Be Appropriate, or Rarely Appropriate based on specific clinical scenarios [4]. These criteria were developed by a voting panel reviewing 864 scenarios [4]. The AAOS Clinical Practice Guideline for Surgical Management of Osteoarthritis of the Knee provides 16 recommendations and seven options based on a systematic review of over 1,500 full-text articles [3]. Additionally, the AAOS Evidence-based Guideline for Surgical Management of Osteoarthritis of the Knee contains 38 recommendations, with 14 classified as Strong, 14 as Moderate, and 10 as Limited [5]. Management of moderate to severe knee OA does not align with AAOS guidelines [10].

Plain Radiography: Radiographic knee osteoarthritis is an imprecise guide to the likelihood that knee pain or disability will be present [19]. Low grading of the severity of knee osteoarthritis pre-operatively is associated with a lower functional level after total knee replacement [40]. A low radiological severity of osteoarthritis was not associated with pain 12 months postoperatively [40].

MRI: Magnetic resonance imaging has created an undeniably important role for reproducible, noninvasive, and objective evaluation and monitoring of cartilage in the setting of trauma, degenerative arthritides, and surgical treatment for cartilage injury [41]. There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration [45]. MR-based disease activity and cumulative damage metrics may be prognostic markers to help identify people at risk for accelerated onset and progression of knee osteoarthritis [62]. Understanding subchondral vascular physiology will be key to better MRI classification and prevention, control, prognosis and treatment of osteoarthritis and other bone diseases [26]. Postoperative improvements in clinical and MRI outcomes after autologous osteochondral transfer at the early term follow-up were maintained through a mean follow-up of 4 years [66]. The extent to which patients ≥ 50 years with degenerative knee disease received a MRI or arthroscopy declined significantly over time, but could not be attributed to a tailored intervention [67].

Other Considerations: Although many OA-related biomarkers are currently available, none can be considered as a surrogate marker of clinical and imaging features for the diagnosis or prognosis of the disease at this time [21]. A Malaysian Delphi consensus on managing knee osteoarthritis presents nine recommendations that advocate an algorithmic approach in the management of patients living with knee OA [13].

Treatment

Non-Operative Management

Management of symptomatic knee osteoarthritis is often multimodal, incorporating lifestyle changes, medications, joint injections, and joint-preserving surgery [6]. This approach can help slow disease progression, provide symptomatic relief, and delay or prevent the need for knee arthroplasty [6]. Nonsurgical treatments include rehabilitation and medical management [54], with physical therapy capable of incorporating a full spectrum of conservative, nonoperative, and postoperative care [59]. A trial of conservative management may be effective and should be considered, especially in patients with moderate osteoarthritis [18].

Most chronic knee pain is managed with medication despite concerns about safety, efficacy, cost, guideline recommendations, and patient preferences [7]. The AAOS Clinical Practice Guideline Summary: Management of Osteoarthritis of the Knee (Nonarthroplasty), Third Edition contains 29 recommendations to assist healthcare professionals in nonarthroplasty management [52]. Evidence supports the use of NSAIDs and acetaminophen for this purpose [52]. Conversely, there is limited evidence for dietary supplements and intra-articular injections in nonarthroplasty management [52].

Self-efficacy at baseline was associated with change over time in pain and physical activity at 3 and 12 months after a supported osteoarthritis self-management programme [16]. Further studies are needed to increase the limited evidence on non-surgical treatments and their combination, to optimize indications, application modalities, and results with particular focus on early OA [15]. Further studies are necessary to increase the limited medical evidence on conservative treatments, optimizing results, application modalities, indications, and focusing on early OA [53]. Current research addresses non-pharmacological conservative treatment of knee OA-related pain to provide important new insights to care recommendations [58], while other trials evaluate how multidisciplinary and multifaceted management affects health outcomes and healthcare costs [12].

Biologic Therapies

There appears to be evidence justifying the use of biologic therapies for knee osteoarthritis management, though more high-level, larger human studies utilizing standardized protocols are needed [2]. The efficacy and safety demonstrated in a placebo-controlled trial support the implementation of intra-articular mesenchymal stromal cells as a treatment option for symptomatic knee OA [33]. The symptomatic treatment effect of SVF injections was found to be dose dependent, and the efficacy, safety, and ease of use supports its use as a treatment option for symptomatic knee osteoarthritis [38]. Adipose tissue derived cell-based therapy is established as safe and effective for reducing pain and improving knee function in symptomatic knee OA in old adults [39].

The efficacy of stem cell therapy for treating knee osteoarthritis and cartilage defects remains unclear, mostly because of the heterogeneity and inconsistency in the sources of cells used for the treatments, different delivery methods, and concomitant surgery [36]. One trial has the potential to provide an effective new therapeutic approach for pain management in knee osteoarthritis [20].

Arthroscopic Surgery

The evidence does not support the effectiveness of arthroscopic knee surgery compared to conservative treatments in knee OA [46]. However, arthroscopic debridement for the management of mild to moderate knee OA is effective at short-term follow-up in patients who have exhausted conservative care [48].

Surgical Guidelines and Appropriateness

The AAOS Appropriate Use Criteria (AUC) for Surgical Management of Osteoarthritis of the Knee categorize treatments as Appropriate, May Be Appropriate, or Rarely Appropriate based on specific clinical scenarios to assist in decision-making [4]. The AAOS AUC developed appropriateness treatment ratings for 864 patient scenarios to help determine the appropriateness of treatments of the heterogeneous patient population routinely seen in practice [9]. The AAOS AUC helps determine the appropriateness of treatments for osteoarthritis of the knee by synthesizing evidence-based information with clinical expertise to improve patient care [8]. The AAOS AUC provide guidance for the surgical management of osteoarthritis of the knee, helping clinicians determine the appropriateness of various surgical options based on patient-specific factors [1].

The AAOS Clinical Practice Guideline Summary of Surgical Management of Osteoarthritis of the Knee provides 16 recommendations and seven options based on a systematic review of over 1,500 full-text articles to assist surgeons in the surgical management of osteoarthritis of the knee [3]. The Surgical Management of Osteoarthritis of the Knee guideline contains 38 recommendations for improving the surgical treatment of patients with osteoarthritis of the knee based on current best evidence, with 14 classified as Strong, 14 as Moderate, and 10 as Limited [5]. Surgical options such as arthroscopic debridement, osteotomy, and arthroplasty each have specific indications and limitations regarding symptom relief and activity return [54].

Complications

Other Considerations: Accelerated knee osteoarthritis is unique from typical knee osteoarthritis [11]. Patients with untreated focal chondral defects (FCDs) of the knee joint are more likely to experience progression of cartilage damage [29]. However, studies on untreated focal chondral defects did not demonstrate the development of radiographically evident osteoarthritis within 2 years of follow-up [29]. Longer-term studies are needed to assess progression toward osteoarthritis and functional deterioration over time following reconstruction of lateral femoral condyle osteochondral lesions [22]. Osteoarthritis is likely to progress after third-generation autologous chondrocyte implantation, although such findings did not affect clinical outcomes in the study population [31].

Recovery

Multimodal management of symptomatic knee osteoarthritis, including lifestyle changes, medications, joint injections, and joint-preserving surgery, can help slow progression, provide symptomatic relief, and delay or prevent the need for knee arthroplasty [6].

Light activity (weeks): Evidence does not specify a week range for light activity or driving.

Full activity (months): Evidence does not specify a month range for full activity or strength return.

Complete recovery / outcome plateau (months): Intra-articular mesenchymal stem cells provide improvements in pain and function in knee osteoarthritis at short-term follow-up (<28 months) in many cases [24]. For intra-articular PRP injection, short-term efficacy is observed with benefits worsening by 24 months compared to 12 months [56]. Articular cartilage debridement for large focal chondral defects in the setting of mild to moderate osteoarthritis results in significant improvements in physical function and knee-specific PROs at minimum one-year follow-up [57]. Osteoarthritis is likely to progress after third-generation autologous chondrocyte implantation, although these findings did not affect the clinical outcome in the study population [31].

Rehabilitation protocol: Evidence does not specify PT phasing, immobilisation duration, or weight-bearing progression.

Functional milestones: Self-efficacy at baseline is associated with change over time in pain and physical activity at 3 and 12 months after a supported osteoarthritis self-management programme [16]. For short-term follow-up (≤1 year), intra-articular PRP injection is more effective than hyaluronic acid (HA) and placebo in terms of pain relief and function improvement in knee osteoarthritis patients, with no difference in adverse event risk between PRP and HA or placebo [25]. At a minimum 6-month follow-up, PRP demonstrated significantly improved pain and function for patients with knee osteoarthritis compared with placebo [28]. Long-term effectiveness data emphasizes the sustained efficacy of PRP, particularly when combined with HA, in providing superior long-term pain relief and functional improvement in knee osteoarthritis compared to other intra-articular injectables [55]. Patients with a preoperative duration of symptomatic medial knee overload/arthritis of two years or greater do not experience inferior PRO or clinical outcomes than patients with a symptom duration of less than 2 years at mid-term follow-up after high tibial osteotomy [30].

Other Considerations: There is substantial variation in the type and cost of nonoperative treatment for patients with late-stage osteoarthritis [81].

Key Evidence

  • [L5] The Appropriate Use Criteria provide guidance for the surgical management of osteoarthritis of the knee, helping clinicians determine the appropriateness of various surgical options based on patient-specific factors. (10.2106/jbjs.16.01484)
  • [L2] Despite these limitations, there appears to be evidence justifying their use for knee osteoarthritis management, though more high-level, larger human studies utilizing standardized protocols are needed. (10.1016/j.arth.2018.12.001)
  • [L1] The guideline provides 16 recommendations and seven options based on a systematic review of over 1,500 full-text articles to assist surgeons in the surgical management of osteoarthritis of the knee. (10.5435/jaaos-d-23-00338)
  • [L5] The AAOS Appropriate Use Criteria (AUC) for Surgical Management of Osteoarthritis of the Knee, developed by a voting panel reviewing 864 scenarios, categorize treatments as Appropriate, May Be Appropriate, or Rarely Appropriate based on specific clinical scenarios to assist in decision-making. (10.5435/jaaos-d-17-00425)
  • [L1] The guideline contains 38 recommendations for improving the surgical treatment of patients with osteoarthritis of the knee based on current best evidence, with 14 classified as Strong, 14 as Moderate, and 10 as Limited. (10.5435/jaaos-d-16-00159)
  • [L4] Most chronic knee pain is managed with medication despite concerns about safety, efficacy and cost, management guidelines recommendations and people's management preferences. (10.1186/1471-2474-9-123)
  • [L5] The American Academy of Orthopaedic Surgeons developed Appropriate Use Criteria to help determine the appropriateness of treatments for osteoarthritis of the knee by synthesizing evidence-based information with clinical expertise to improve patient care. (10.5435/jaaos-22-04-256)
  • [L5] The AUC for the Surgical Management of Osteoarthritis of the Knee developed appropriateness treatment ratings for 864 patient scenarios to help determine the appropriateness of treatments of the heterogeneous patient population routinely seen in practice. (10.5435/jaaos-d-17-00424)
  • [L4] Management of moderate to severe knee OA does not align with AAOS guidelines. (10.5435/jaaos-d-17-00164)
  • [L5] Accelerated knee osteoarthritis is unique from typical knee osteoarthritis. (10.1186/s12891-020-03367-2)
  • [L1] This trial will provide results on how multidisciplinary and multifaceted management of patients with OA affects health outcomes and health care costs. (10.1186/1471-2474-11-253)
  • [L5] This consensus presents nine recommendations that advocate an algorithmic approach in the management of patients living with knee OA. (10.1186/s12891-021-04381-8)
  • [L4] The paper provides an updated review of the current status of the diagnosis and definition of early knee OA, including clinical, radiographical, histological, MRI, and arthroscopic definitions and biomarkers, presenting practical classification criteria based on current evidence. (10.1007/s00167-016-4068-3)
  • [L4] Further studies are needed to increase the limited evidence on non-surgical treatments and their combination, to optimize indications, application modalities, and results with particular focus on early OA. (10.1007/s00167-016-4089-y)
  • [L3] Self-efficacy at baseline was associated with change over time in pain and physical activity at 3 and 12 months after the supported osteoarthritis self-management programme. (10.1186/s12891-020-03407-x)
  • [L1] A trial of conservative management may be effective and should be considered, especially in patients with moderate osteoarthritis. (10.1302/0301-620x.98b7.37410)
  • [L1] Radiographic knee osteoarthritis is likewise an imprecise guide to the likelihood that knee pain or disability will be present. (10.1186/1471-2474-9-116)
  • [L2] This trial has the potential to provide an effective new therapeutic approach for pain management in knee osteoarthritis. (10.1186/s12891-021-04690-y)
  • [L5] Although many OA-related biomarkers are currently available, none can be considered as a surrogate marker of clinical and imaging features for the diagnosis or prognosis of the disease at this time. (10.1186/1471-2474-16-s1-s2)
  • [L4] Longer-term studies are needed to assess progression toward osteoarthritis and functional deterioration over time. (10.1016/j.otsr.2021.103051)
  • [L4] This study identified speciality-related variability in some aspects of the management of knee OA. (10.1186/1471-2474-12-72)
  • [L2] Intraarticular MSCs provide improvements in pain and function in knee osteoarthritis at short-term follow-up (<28 months) in many cases. (10.1016/j.arthro.2018.07.028)
  • [L1] For short-term follow-up (≤1 year), intra-articular PRP injection is more effective in terms of pain relief and function improvement in the treatment of KOA patients than HA and placebo, and there is no difference in the risk of an adverse event between PRP and HA or placebo. (10.1186/s13018-019-1363-y)
  • [L4] Understanding subchondral vascular physiology will be key to better MRI classification and prevention, control, prognosis and treatment of osteoarthritis and other bone diseases. (10.1530/eor-23-0002)
  • [L1] At a minimum 6-month follow-up, PRP demonstrated significantly improved pain and function for patients with knee osteoarthritis compared with placebo. (10.1016/j.arthro.2024.01.037)
  • [L3] Patients with untreated FCDs of the knee joint are more likely to experience a progression of cartilage damage, although the studies included in this review did not demonstrate the development of radiographically evident OA within 2 years of follow-up. (10.1177/2325967118801931)
  • [L4] Patients with a preoperative duration of symptomatic medial knee overload/arthritis of two years or greater do not experience inferior PRO or clinical outcomes than patients with a symptom duration of less than 2 years at mid-term follow-up. (10.1016/j.jisako.2022.03.003)
  • [L4] These findings did not affect the clinical outcome in the study population, although osteoarthritis is likely to progress. (10.1177/03635465231162107)
  • [L1] The efficacy and safety demonstrated in this placebo-controlled trial support its implementation as a treatment option for symptomatic knee OA. (10.1177/0363546519899923)
  • [L1] Optimal management of cartilage defects is controversial, and future rigorous research methods could minimize common biases through strict study design and patient selection criteria, larger patient enrollment, more extended follow-up, and standardization of clinical treatment pathways. (10.1016/j.arthro.2012.02.022)
  • [L2] Knee biomechanical markers are associated with patient-reported knee function to a greater extent than X-ray grading, but both provide complementary information in the assessment of OA patients. (10.1186/s12891-022-05845-1)
  • [L5] The efficacy of stem cell therapy for treating knee osteoarthritis and cartilage defects remains unclear, mostly because of the heterogeneity and inconsistency in the sources of cells used for the treatments, different delivery methods, and concomitant surgery. (10.1016/j.arthro.2020.07.035)
  • [L5] Orthopaedic surgeons must critically analyze literature and improve treatment efficacy to counter guidelines that limit patient access to care based on flawed analyses, while promoting innovative modalities like meniscal repair to ameliorate disability associated with osteoarthritis of the knee. (10.1016/j.arthro.2017.10.014)
  • [L1] The symptomatic treatment effect was found to be dose dependent, and the efficacy of SVF injections, in combination with its safety and ease of use, supports its use as a treatment option for symptomatic knee osteoarthritis. (10.1177/2325967120s00127)
  • [L1] The therapy is established as safe and effective for reducing pain and improving knee function in symptomatic knee OA in old adults. (10.3390/cells10061365)
  • [L3] A low radiological severity of osteoarthritis was not associated with pain 12 months postoperatively. (10.1302/0301-620x.96b11.33726)
  • [L5] Magnetic resonance imaging has created an undeniably important role for reproducible, noninvasive, and objective evaluation and monitoring of cartilage in the setting of trauma, degenerative arthritides, and surgical treatment for cartilage injury. (10.1177/0363546505281938)
  • [L5] The effort of the ESSKA Cartilage Committee in defining early OA and the potential of available therapeutic options may lead to an improvement in the current treatment algorithm. (10.1007/s00167-011-1858-5)
  • [L3] Although clinical evidence supports brace use to improve pain and functional ability, current biomechanical evidence suggests that unloading of the affected knee compartment does not significantly hinder disease progression. (10.1007/s00167-014-3305-x)
  • [L4] Failure definitions of cartilage treatments differ in scientific articles, generating confusion and heterogeneous data. (10.1007/s00167-014-3272-2)
  • [L1] There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. (10.1177/0363546511407612)
  • [L1] The evidence does not support the effectiveness of arthroscopic knee surgery compared to conservative treatments in knee OA. (10.1186/s12891-024-07813-3)
  • [L5] Patellofemoral kinematics and retropatellar pressure change after TKA in different manners depending on the type of TKA used. (10.1007/s00167-017-4772-7)
  • [L4] Arthroscopic debridement for the management of mild to moderate knee OA is effective at short-term follow-up in patients who have exhausted conservative care. (10.1016/j.arthro.2024.03.016)
  • [L1] The guideline contains 29 recommendations to assist healthcare professionals in the nonarthroplasty management of osteoarthritis of the knee, with evidence supporting the use of NSAIDs and acetaminophen while noting limited evidence for dietary supplements and intra-articular injections. (10.5435/jaaos-d-21-01233)
  • [L4] Further studies are necessary to increase the limited medical evidence on conservative treatments, optimizing results, application modalities, indications, and focusing on early OA. (10.1007/s00167-011-1713-8)
  • [L5] Nonsurgical treatments include rehabilitation and medical management, while surgical options such as arthroscopic debridement, osteotomy, and arthroplasty each have specific indications and limitations regarding symptom relief and activity return. (10.5435/00124635-199911000-00005)
  • [L1] These findings emphasize the sustained efficacy of PRP, particularly when combined with HA, in providing superior long-term pain relief and functional improvement in knee OA compared to other intra-articular injectables, highlighting its potential as a preferred treatment modality. (10.1186/s13018-025-05574-w)
  • [L3] Treatment with PRP injections can reduce pain and improve knee function and quality of life with short-term efficacy, though benefits worsen by 24 months compared to 12 months. (10.1007/s00167-010-1238-6)
  • [L3] Articular cartilage debridement for large focal chondral defects in the setting of mild to moderate osteoarthritis results in significant improvements in physical function and knee-specific PROs at minimum one-year follow-up. (10.1177/2325967125s00234)
  • [L2] This study addresses the current topic of non-pharmacological conservative treatment of knee OA-related pain and anticipates that the results will provide important new insights to the current care recommendations. (10.1186/1471-2474-14-46)
  • [Paper] Physical therapy management of osteochondritis dissecans can incorporate a full spectrum of conservative, nonoperative, and postoperative care. (10.1016/j.csm.2014.01.001)
  • [L5] Recent evidence suggests that recurrent patellofemoral instability is causing cartilage degeneration, and stopping this process via surgical restoration of the anatomy and biomechanics of the patellofemoral joint may significantly reduce the risk of osteoarthritis. (10.1016/j.arthro.2022.10.003)
  • [L5] Changes in the physiological state of chondrocytes are the initiating factors in the pathogenesis of knee OA. (10.1186/s12891-021-04281-x)
  • [L2] MR-based disease activity and cumulative damage metrics may be prognostic markers to help identify people at risk for accelerated onset and progression of knee osteoarthritis. (10.1186/s12891-020-03338-7)
  • [Paper] The combination of altered stance phase loading and reduced walking speed characteristic of OA gait may disrupt biphasic lubrication mechanisms, thereby contributing to increased friction. (10.1002/ksa.70225)
  • [L5] Bioenhanced ACL repair produces a ligament that is biomechanically similar to an ACL graft and provides chondro protection to the joint after ACL surgery. (10.1177/0363546513483446)
  • [L4] Postoperative improvements in clinical and MRI outcomes after AOT at the early term follow-up were maintained through a mean follow-up of 4 years. (10.1177/23259671251356267)
  • [L3] The extent to which patients ≥ 50 years with degenerative knee disease received a MRI or arthroscopy declined significantly over time, but could not be attributed to the tailored intervention. (10.1007/s00167-022-06949-w)
  • [L4] Our results suggest that the personalised biomechanical treatment can improve gait patterns, pain, function and quality of life. (10.1186/s12891-020-03382-3)
  • [L5] The results of this in vitro study suggested that the friction of cadaveric knee joint tissues does not increase with progressing degeneration. (10.1007/s00167-023-07602-w)
  • [L1] Nevertheless, both can significantly correct knee varus deformity and improve knee function; their early knee function scores are also similar. (10.1186/s13018-023-03725-5)
  • [L2] Preoperative quantitative pivot shift does not correlate with in vivo kinematics following ACL reconstruction with or without lateral extraarticular tenodesis, although it does correlate with healthy in vivo knee kinematics in the contralateral extremity. (10.1007/s00167-022-07232-8)
  • [L4] The limited excursion of the quadriceps muscle is the main limiting factor to knee flexion. (10.1016/j.arth.2008.01.247)
  • [L1] However, evidence of improvement in knee functions remains limited. (10.1177/23259671221133784)
  • [L2] There was no change in sagittal plane knee moment, including flexion and extension moments, from before to after medial open wedge HTO. (10.1186/s12891-019-2472-9)
  • [L1] In addition, PRP did not confer superiority when assessing knee-related structural changes. (10.1016/j.arth.2022.05.014)
  • [L1] The VER-brace obtained more effectiveness than FO on pain and KAM after 3 months for medial knee osteoarthritis and the combined treatment did not substantially improve biomechanical and functional outcomes. (10.1002/ksa.12312)
  • [L3] There is substantial variation in the type and cost of nonoperative treatment for patients with late-stage OA. (10.2106/jbjs.21.01415)

See Also

References

[1] The American Academy of Orthopaedic Surgeons Appropriate Use Criteria for Surgical Management of Osteoarthritis of the Knee. Journal of Bone and Joint Surgery. 2017. DOI: 10.2106/jbjs.16.01484

[2] Biologic Therapies for the Treatment of Knee Osteoarthritis. The Journal of Arthroplasty. 2019. DOI: 10.1016/j.arth.2018.12.001

[3] American Academy of Orthopaedic Surgeons Clinical Practice Guideline Summary of Surgical Management of Osteoarthritis of the Knee. Journal of the American Academy of Orthopaedic Surgeons. 2023. DOI: 10.5435/jaaos-d-23-00338

[4] AAOS Appropriate Use Criteria: Surgical Management of Osteoarthritis of the Knee. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00425

[5] Surgical Management of Osteoarthritis of the Knee: Evidence-based Guideline. Journal of the American Academy of Orthopaedic Surgeons. 2016. DOI: 10.5435/jaaos-d-16-00159

[6] Chapter 20 Nonarthroplasty Management of Osteoarthritis of the Knee. 2019.

[7] Management of chronic knee pain: A survey of patient preferences and treatment received. BMC Musculoskeletal Disorders. 2008. DOI: 10.1186/1471-2474-9-123

[8] Non-Arthroplasty Treatment of Osteoarthritis of the Knee. Journal of the American Academy of Orthopaedic Surgeons. 2014. DOI: 10.5435/jaaos-22-04-256

[9] Surgical Management of Osteoarthritis of the Knee. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00424

[10] Compliance With the AAOS Guidelines for Treatment of Osteoarthritis of the Knee: A Survey of the American Association of Hip and Knee Surgeons. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00164

[11] Risk factors and the natural history of accelerated knee osteoarthritis: a narrative review. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03367-2

[12] Multidisciplinary and multifaceted outpatient management of patients with osteoarthritis: protocol for a randomised, controlled trial. BMC Musculoskeletal Disorders. 2010. DOI: 10.1186/1471-2474-11-253

[13] A Malaysian Delphi consensus on managing knee osteoarthritis. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04381-8

[14] Early osteoarthritis of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2016. DOI: 10.1007/s00167-016-4068-3

[15] Non‐surgical treatments for the management of early osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2016. DOI: 10.1007/s00167-016-4089-y

[16] High self-efficacy – a predictor of reduced pain and higher levels of physical activity among patients with osteoarthritis: an observational study. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03407-x

[18] The role for arthroscopic partial meniscectomy in knees with degenerative changes. The Bone & Joint Journal. 2016. DOI: 10.1302/0301-620x.98b7.37410

[19] The discordance between clinical and radiographic knee osteoarthritis: A systematic search and summary of the literature. BMC Musculoskeletal Disorders. 2008. DOI: 10.1186/1471-2474-9-116

[20] Effect of low-dose amitriptyline on reducing pain in clinical knee osteoarthritis compared to benztropine: study protocol of a randomised, double blind, placebo-controlled trial. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04690-y

[21] Biomarkers of prognosis and efficacy of treatment in OA. BMC Musculoskeletal Disorders. 2015. DOI: 10.1186/1471-2474-16-s1-s2

[22] Good medium-term functional results in reconstruction of lateral femoral condyle osteochondral lesions. Orthopaedics & Traumatology: Surgery & Research. 2022. DOI: 10.1016/j.otsr.2021.103051

[23] Comparison of general practitioners and rheumatologists' prescription patterns for patients with knee osteoarthritis. BMC Musculoskeletal Disorders. 2011. DOI: 10.1186/1471-2474-12-72

[24] Intra-articular Mesenchymal Stem Cells in Osteoarthritis of the Knee: A Systematic Review of Clinical Outcomes and Evidence of Cartilage Repair. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2019. DOI: 10.1016/j.arthro.2018.07.028

[25] Intra-articular platelet-rich plasma injection for knee osteoarthritis: a summary of meta-analyses. Journal of Orthopaedic Surgery and Research. 2019. DOI: 10.1186/s13018-019-1363-y

[26] Walking on water: subchondral vascular physiology explains how joints work and why they become osteoarthritic. EFORT Open Reviews. 2023. DOI: 10.1530/eor-23-0002

[28] Platelet‐Rich Plasma, Bone Marrow Aspirate Concentrate, and Hyaluronic Acid Injections Outperform Corticosteroids in Pain and Function Scores at a Minimum of 6 Months as Intra‐Articular Injections for Knee Osteoarthritis: A Systematic Review and Network Meta‐analysis. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.01.037

[29] Do Focal Chondral Defects of the Knee Increase the Risk for Progression to Osteoarthritis? A Review of the Literature. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118801931

[30] Preoperative symptom duration does not affect clinical outcomes after high tibial osteotomy at a minimum of 2-year follow-up. Journal of ISAKOS. 2022. DOI: 10.1016/j.jisako.2022.03.003

[31] Long-term Assessment of Subchondral Bone Changes and Intralesional Bony Overgrowth After Third-Generation Autologous Chondrocyte Implantation: A Retrospective Study. The American Journal of Sports Medicine. 2023. DOI: 10.1177/03635465231162107

[33] Clinical Efficacy of Intra-articular Mesenchymal Stromal Cells for the Treatment of Knee Osteoarthritis: A Double-Blinded Prospective Randomized Controlled Clinical Trial. The American Journal of Sports Medicine. 2020. DOI: 10.1177/0363546519899923

[34] Limitations and Sources of Bias in Clinical Knee Cartilage Research. Arthroscopy. 2012. DOI: 10.1016/j.arthro.2012.02.022

[35] Biomechanical markers associations with pain, symptoms, and disability compared to radiographic severity in knee osteoarthritis patients: a secondary analysis from a cluster randomized controlled trial. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05845-1

[36] Editorial Commentary: Stem Cell Therapy for the Knee: Heterogeneity in Cell Sources, Delivery Methods, and Concomitant Surgery Needs to Be Considered. Arthroscopy. 2021. DOI: 10.1016/j.arthro.2020.07.035

[37] Editorial Commentary: Are We Running Out of Treatments for Osteoarthritis of the Knee?. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2017.10.014

[38] Clinical Efficacy Of Intra-articular Mesenchymal Stem Cells For The Treatment Of Knee Osteoarthritis: A Double Blinded, Prospective, Randomized, Controlled Clinical Trial. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120s00127

[39] Meta-Analysis of Adipose Tissue Derived Cell-Based Therapy for the Treatment of Knee Osteoarthritis. Cells. 2021. DOI: 10.3390/cells10061365

[40] Low grading of the severity of knee osteoarthritis pre-operatively is associated with a lower functional level after total knee replacement. The Bone & Joint Journal. 2014. DOI: 10.1302/0301-620x.96b11.33726

[41] Magnetic Resonance Imaging of Articular Cartilage. The American Journal of Sports Medicine. 2006. DOI: 10.1177/0363546505281938

[42] Early osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2011. DOI: 10.1007/s00167-011-1858-5

[43] Current state of unloading braces for knee osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-3305-x

[44] Cartilage failures. Systematic literature review, critical survey analysis, and definition. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-3272-2

[45] The Clinical Utility and Diagnostic Performance of Magnetic Resonance Imaging for Identification of Early and Advanced Knee Osteoarthritis. The American Journal of Sports Medicine. 2011. DOI: 10.1177/0363546511407612

[46] Arthroscopic surgery is not superior to conservative treatment in knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trails. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07813-3

[47] Medial stabilized and posterior stabilized TKA affect patellofemoral kinematics and retropatellar pressure distribution differently. Knee Surgery, Sports Traumatology, Arthroscopy. 2017. DOI: 10.1007/s00167-017-4772-7

[48] Arthroscopic Debridement of Mild and Moderate Knee Osteoarthritis Results in Clinical Improvement at Short‐Term Follow‐Up: A Systematic Review. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.03.016

[52] AAOS Clinical Practice Guideline Summary: Management of Osteoarthritis of the Knee (Nonarthroplasty), Third Edition. Journal of the American Academy of Orthopaedic Surgeons. 2022. DOI: 10.5435/jaaos-d-21-01233

[53] Non‐surgical management of early knee osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2011. DOI: 10.1007/s00167-011-1713-8

[54] Degenerative Arthritis of the Knee in Active Patients: Evaluation and Management. Journal of the American Academy of Orthopaedic Surgeons. 1999. DOI: 10.5435/00124635-199911000-00005

[55] Long-term effectiveness of intra-articular injectables in patients with knee osteoarthritis: a systematic review and Bayesian network meta-analysis. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-05574-w

[56] Platelet‐rich plasma intra‐articular knee injections for the treatment of degenerative cartilage lesions and osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-010-1238-6

[57] Poster 137: Articular Cartilage Debridement Results in Increases in Patient-Reported Outcomes in Large Focal Chondral Defects in the Setting of Mild to Moderate Knee Osteoarthritis. Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/2325967125s00234

[58] Effectiveness of a cognitive-behavioral group intervention for knee osteoarthritis pain: protocol of a randomized controlled trial. BMC Musculoskeletal Disorders. 2013. DOI: 10.1186/1471-2474-14-46

[59] Physical Therapy Management of Patients with Osteochondritis Dissecans. Clinics in Sports Medicine. 2014. DOI: 10.1016/j.csm.2014.01.001

[60] Editorial Commentary: Patellofemoral Instability Results in Osteoarthritis, and Nonanatomic Surgery and Surgical Over‐constraint May Also Cause Osteoarthritis. Arthroscopy. 2023. DOI: 10.1016/j.arthro.2022.10.003

[61] Experimental observation of the sequence of tibial plateau chondrocyte and matrix degeneration in spontaneous osteoarthritis in Guinea pigs. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04281-x

[62] Composite quantitative knee structure metrics predict the development of accelerated knee osteoarthritis: data from the osteoarthritis initiative. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03338-7

[63] Gait alterations increase friction of degenerated articular cartilage: A tribological study. Knee Surgery, Sports Traumatology, Arthroscopy. 2025. DOI: 10.1002/ksa.70225

[65] Use of a Bioactive Scaffold to Stimulate Anterior Cruciate Ligament Healing Also Minimizes Posttraumatic Osteoarthritis After Surgery. The American Journal of Sports Medicine. 2013. DOI: 10.1177/0363546513483446

[66] Autologous Osteochondral Transfer Demonstrates Satisfactory Clinical Outcomes and Durable Cartilage Properties: A Mean 4-Year Follow-up Using Quantitative MRI. Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/23259671251356267

[67] A tailored intervention does not reduce low value MRI’s and arthroscopies in degenerative knee disease when the secular time trend is taken into account: a difference‐in‐difference analysis. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-06949-w

[68] The effect of treatment with a non-invasive foot worn biomechanical device on subjective and objective measures in patients with knee osteoarthritis- a retrospective analysis on a UK population. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03382-3

[69] Impact of hyaluronic acid injection on the knee joint friction. Knee Surgery, Sports Traumatology, Arthroscopy. 2023. DOI: 10.1007/s00167-023-07602-w

[70] Is proximal tibial tubercle osteotomy superior to distal tibial tubercle osteotomy for medial compartmental osteoarthritis? A meta-analysis. Journal of Orthopaedic Surgery and Research. 2023. DOI: 10.1186/s13018-023-03725-5

[71] Preoperative quantitative pivot shift does not correlate with in vivo kinematics following ACL reconstruction with or without lateral extraarticular tenodesis. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-07232-8

[72] Does Quad Release Improve Knee Flexion in the Arthritic Knee?. The Journal of Arthroplasty. 2008. DOI: 10.1016/j.arth.2008.01.247

[73] Intra-articular Injection of Mesenchymal Stem Cells After High Tibial Osteotomy: A Systematic Review and Meta-analysis. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671221133784

[74] Change in adduction moment following medial open wedge high tibial osteotomy: a meta-analysis. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2472-9

[75] The Efficacy of Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis Symptoms and Structural Changes: A Systematic Review and Meta-Analysis. The Journal of Arthroplasty. 2022. DOI: 10.1016/j.arth.2022.05.014

[76] Knee braces and foot orthoses multimodal 3‐month treatment of medial knee osteoarthritis in a randomised crossover trial. Knee Surgery, Sports Traumatology, Arthroscopy. 2024. DOI: 10.1002/ksa.12312

[81] Costs of Nonoperative Procedures for Knee Osteoarthritis in the Year Prior to Primary Total Knee Arthroplasty. Journal of Bone and Joint Surgery. 2022. DOI: 10.2106/jbjs.21.01415

Creative Commons BY-NC 4.0

CC Creative Commons licence
BY Attribution — you must credit the source
NC NonCommercial — not for commercial use

Attribution-NonCommercial 4.0 International

Creative Commons Corporation ("Creative Commons") is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an "as-is" basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.

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.