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Demographics & Risk

Demographic and socioeconomic drivers of knee pathology, focusing on risk factors for osteoarthritis and ACL injury across age, sex, and BMI.

Overview

Demographic and anthropometric factors significantly influence surgical candidacy and outcomes across orthopaedic procedures. Advanced age is not associated with adverse postoperative outcomes after high tibial osteotomy [1]. Instead, cartilage status determines outcomes [1], and advanced age should be considered a potential indication for open wedge high tibial osteotomy rather than a risk factor [1]. For younger patients, fixed-bearing medial unicompartmental knee arthroplasty demonstrates low complication rates, good-to-excellent long-term patient outcomes, and satisfactory implant survival in patients aged 60 years or younger at minimum 10-year follow-up [2].

Body mass index (BMI) thresholds and weight status present distinct risk profiles. A BMI greater than 45 kg/m2 is associated with dramatically increased postoperative complications in total knee arthroplasty [17] and total hip arthroplasty [17]. Conversely, underweight BMI is associated with increased in-hospital complications and increased length of stay after revision total joint arthroplasty [35]. Using BMI alone to determine eligibility for total hip arthroplasty did not improve the rate of clinically meaningful improvements in patient-reported outcomes [16]. Standardized preoperative protocols should be developed to improve outcomes in underweight patients undergoing revision total joint arthroplasty [35].

Sex and socioeconomic status further stratify risk and access. Females experience inferior outcomes, higher rates of revisions, and higher rates of postoperative complications after anatomic total shoulder arthroplasty compared to males [41]. In the United States, insurance status and income proxies are consistent predictors of disparities in access to care and outcomes after medial patellofemoral ligament reconstruction [8]. Patients with lower insurance status or income experience longer wait times from injury to clinic evaluation [8] and have reduced odds of being selected as candidates for medial patellofemoral ligament reconstruction [8].

Specific patient populations require tailored management. A small subset of higher-risk patients requires nonhome discharge after total hip arthroplasty [6], and these patients experience worse outcomes [6]. Patients with a Nottingham Hip Fracture Score of six or greater are considered higher risk [7]. Demographics and surgery-related complications lead to 30-day readmission rates among knee arthroscopic procedures [14], requiring clinicians to carefully weigh risk factors when considering surgical and non-surgical approaches for patients at higher risk of inferior surgical outcomes after knee arthroscopy [14]. Simultaneous and staged bilateral total knee arthroplasty yield comparable clinical outcomes and complication rates across all age groups [30]. Finally, patients with congenital insensitivity to pain require close follow-up to prevent complications during guided growth for knee deformity correction [15], and stringent patient selection criteria should be followed for guided growth in these patients [15].

Anatomy & Pathophysiology

Osseous Morphology and Kinetics

Accelerometer-measured physical activity correlates with knee breadth in middle-aged Finns [38], suggesting that moderate-to-vigorous physical activity (MVPA) may increase knee dimensions via biomechanical mechanisms analogous to those influencing diaphyseal morphology [38]. In male Chinese osteoarthritis patients, femoral varus deformity is the predominant phenotype, and functional knee phenotypes vary significantly across geographic regions [81]. High-risk knee morphology identified at an earlier age indicates that anatomical measurements can help identify predisposition toward ACL injury [60].

Ligamentous Integrity and Failure Mechanics

The posterior portion of the femoral insertion site of the ACL plays a significant role in resisting anterior tibial load during knee extension [91]. However, the failure load of this posterior insertion site decreases significantly when the knee is in flexion [91]. The most common ACL injury mechanism occurs without direct contact, typically involving extension during deceleration or momentum shift, which generates valgus and rotational forces [39]. A comprehensive understanding of these forces and risk factors is essential for developing improved preventive strategies [84].

Kinematics and Neuromuscular Control

Knee motion and loading during landing tasks predict ACL injury risk in female athletes [62]. The early peak knee abduction moment waveform serves as a novel risk factor for predicting ACL injury in young athletes [45]. Utilizing waveforms rather than discrete peak values of the knee abduction moment may more accurately represent risky movement patterns [45]. During single-leg drop landings, dual-task conditions increase maximum internal tibial rotation angle and anterior tibial translation compared to single-task conditions, indicating that neurocognitive load disturbs balance and alters knee biomechanics [57]. The kinematics of the dominant and nondominant legs in female soccer players differ regarding knee valgus angle during a single-leg drop vertical jump (DVJ) [75]. Furthermore, the DVJ task header exhibits kinetic and kinematic parameters suggesting increased ACL injury risk compared to the standard DVJ task [80].

Joint Stiffness and Patellofemoral Dynamics

Women exhibit lower knee stiffness in response to low magnitudes of applied torque compared to men, but demonstrate increased joint stiffness as the magnitude of applied torque rises [53]. Patellofemoral kinematics and retropatellar pressure change after total knee arthroplasty (TKA) in manners dependent on the specific type of TKA used [56]. Patellofemoral pain (PFP) may result from a combination of physical activity occurring within the context of pathological kinematics [78].

Assessment Tools and Pathological Models

A noninvasive device provides objective information on knee kinematics and serves as a useful tool for investigating preoperative and postoperative influences on tibiofemoral rotation [58]. In patients with severe knee osteoarthritis, no significant associations exist between pain catastrophizing and objective knee function (range of motion and muscle strength) or knee biomechanics during gait [63]. Localized incongruity has been shown to initiate biomechanical abnormalities consistent with causing cartilage degeneration in a rabbit knee model [92]. Identifying biomechanical mechanisms that place young athletes at risk for hip injury enables anticipatory guidance and preventative strategies [88].

Classification

Nottingham Hip Fracture Score (NHFS): A score of six or higher identifies patients as 'higher risk' [7]. Identification of such risk factors provides direction for targeted prophylactic treatment to high-risk individuals [9].

Patient Health Status: In primary total hip arthroplasty, self-rated health (SRH), ASA classification, and comorbidity count show increasing risks of medical complications and death with decreasing health status [59]. Independent predictors of complications after knee arthroscopy include patients with high ASA classification, dependent functional status, renal comorbidities, and a recent history of wound infection [77].

Disease Severity Classification: The vast majority of randomized controlled trials (RCTs) of total knee arthroplasty (>85%) did not enroll patients based on disease severity, as measured by PROM score thresholds or radiographic classifications, in their inclusion criteria [24]. Experts identified a large number of characteristics for describing patients with knee osteoarthritis [19].

Other Considerations: Measures of disease frequency such as prevalence and incidence and measures of association such as relative risk and odds ratios are basic tools that help to quantify the relationship between exposures to risk factors and diseases or injuries [26]. There are substantial differences in reported prevalence rates for upper-extremity musculoskeletal disorders (UEDs), mainly due to the absence of a universally accepted way of labelling or defining UEDs [83]. The prevalence of specific injury types in mixed martial arts competitions varied by competition level, match result, and match winners versus losers [86]. Severe injury rates and patterns varied by sport, gender, and type of exposure among United States high school athletes [90]. Demographic subsets most at risk for increased incidence of associated intra-articular injuries with delayed anterior cruciate ligament (ACL) reconstruction were males, adults between 26 and 39 years old, overweight individuals, and those whose ACL tears occurred while playing sports [94]. Significant diversity in patient, injury, and surgical factors exists among large prospective cohorts of patients undergoing ACL reconstruction collected in different locations [95].

Clinical Presentation

Demographics and Risk Stratification: Advanced age alone is not associated with adverse postoperative outcomes after high tibial osteotomy; rather, cartilage status determines these outcomes [1]. However, older age predicts inferior patient-reported outcomes one year after anterior cruciate ligament reconstruction, a trend also observed in patients with higher BMI, female sex, or those undergoing meniscal repair [46]. The estimated lifetime risk of revision knee arthroplasty varies by patient sex, age, and underlying diagnosis [3]. Sociodemographic variables, including ethnicity/race, education, income, and age, may contribute to increased knee pain risk in non-Hispanic Black and non-Hispanic White adults [36].

Insurance and Access: Specific insurance status and income characteristics are associated with longer wait times from injury to clinic evaluation and reduced odds of selection as a candidate for medial patellofemoral ligament reconstruction [8].

Acute Injury and Concussion Patterns: Concussions represent the most common injury diagnosis among intercollegiate water polo athletes and exhibit the worst return-to-play outcomes among common diagnoses in this population [50]. Individuals reporting at least one previous undiagnosed concussion exhibit worse baseline clinical indicators [11]. Certain variables are associated with increased symptoms across multiple concussion clusters in collegiate athletes, while other variables correlate with more specific symptom presentations [37]. Early detection through thorough knowledge of signs and symptoms is critical for management [42]. Sex- and age-related differences exist in diagnoses and injury mechanisms for emergency department visits involving ankle-related basketball injuries [32]. Identification of risk factors for anterior cruciate ligament injuries in female athletes provides direction for targeted prophylactic treatment [9].

Chronic Pain and Osteoarthritis Presentation: Presentation factors increasing the likelihood of a diagnostic X-ray for knee pain include pain lasting longer than 6 months, the presence of medial or diffuse pain, and mechanical symptoms [12]. Experts have identified a large number of characteristics for describing patients with knee osteoarthritis [19]. The Knee Pain and Related Health in the Community (KPIC) study aims to identify risk factors for knee pain through baseline and longitudinal assessments up to Year 3 [10]. The HONEUR knee cohort is characterized by its size, setting, and range of age and type of knee complaints [18]. The Research in Osteochondritis Dissecans of the Knee (ROCK) prospective cohort is used to understand the initial presentation and symptoms of osteochondritis dissecans [47].

Comorbidities and Systemic Factors: Patient age, BMI, and specific non-modifiable comorbidities showed no clinically relevant change in primary total knee arthroplasty patients from 2008 to 2018 [34]. A small subset of higher-risk patients requires nonhome discharge after total hip arthroplasty and experiences worse outcomes [6]. Patients contracting COVID-19 infection between 8 and 30 days after initial hip fracture presentation are at higher mortality risk [20]. Neck pain in elderly men is common, though symptoms and morbidity vary [44].

Investigations

Plain radiography: Presentation factors that increase the likelihood of obtaining a diagnostic X-ray include pain lasting longer than 6 months, the presence of medial or diffuse pain, and mechanical symptoms [12]. Pre-existing significant radiological patellofemoral disease does not affect 10-year survivorship in fixed bearing unicompartmental knee arthroplasty [13]. Patients with significant preoperative radiological patellofemoral disease achieve excellent functional outcomes 10 years postoperatively in fixed bearing unicompartmental knee arthroplasty [13]. Low radiological severity of osteoarthritis pre-operatively is associated with a lower functional level after total knee replacement [70]. Low radiological severity of osteoarthritis pre-operatively is not associated with pain 12 months postoperatively after total knee replacement [70]. Kellgren and Lawrence grade 1 at baseline is associated with an increased risk of incident radiographic knee osteoarthritis [82]. Bilateral knee osteoarthritis is very common with time, as the majority of sufferers eventually develop radiographic disease in both knees [100].

MRI: Clinical-grade MRI-based methods using MRIs downgraded to clinical-grade resolution can identify knee anatomic factors that predict ACL injury risk in male and female athletes [48]. Patients with more severe imaging lesions of knee osteoarthritis tend to have poorer range of motion [51]. Protective clinical parameters and quantitative and semi-quantitative MR-imaging parameters are associated with maintaining radiographically normal knee joints in an older population over 8 years [68].

Other Considerations: Advanced age is not associated with adverse postoperative outcomes after high tibial osteotomy [1]. Cartilage status, rather than age, determines outcomes after high tibial osteotomy [1] The estimated lifetime risk of revision knee arthroplasty varies depending on patient sex, age, and underlying diagnosis [3]. Surgical incidence after knee MRI is likely appropriately lower for older patients [49]. The vast majority of randomized controlled trials of total knee arthroplasty (>85%) did not enroll patients based on disease severity measured by PROM score thresholds or radiographic classifications [24]. Meniscal allograft size can be predicted by height, weight, and gender [79]. Advanced age is associated with an increased risk of incident radiographic knee osteoarthritis [82]. Female sex is associated with an increased risk of incident radiographic knee osteoarthritis [82]. Overweight is associated with an increased risk of incident radiographic knee osteoarthritis [82]. Less range of motion is associated with an increased risk of incident radiographic knee osteoarthritis [82]. Radiographic measurements of severity have a relatively small influence on EOSQ scores in children with early-onset scoliosis [85].

Treatment

Non-Operative

Non-operative management is a viable initial strategy for specific populations. Nonoperative treatment of ACL injuries failed in 60% of patients and was highly correlated with age and activity level [99]. However, conservative management should be considered before surgical treatment is indicated for pubalgia in athletes [66]. For the middle-aged population with moderate activity levels, non-operative treatment with optional delayed ACL reconstruction may be the more cost-effective strategy [52]. Of patients treated nonoperatively for 1 year after ACL tears, 32% underwent delayed ACL reconstruction [89]. Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management [74]. Therapy with zoledronic acid did not reduce all-cause mortality in older patients with femoral neck fracture [67].

Operative

Indications: Advanced age should not be identified as a risk factor for adverse postoperative outcomes after high tibial osteotomy, as cartilage status rather than age determines outcomes [1]. There is currently no evidence that obesity should be considered a definite contraindication to unicompartmental knee arthroplasty [31]. Using body mass index (BMI) alone to determine eligibility for total hip arthroplasty did not improve the rate of clinically meaningful improvements in patient-reported outcomes [16]. Patients with a Nottingham Hip Fracture Score (NHFS) ≥ six should be considered 'higher risk' [7]. A small subset of higher-risk patients requires nonhome discharge after total hip arthroplasty and experiences worse outcomes [6]. Delayed reconstruction and high BMI z score increase the risk of meniscal tear in paediatric and adolescent anterior cruciate ligament injury [74]. A multivariable model based on individual risk factors can identify patients who are at high risk for recurrent lateral patellar dislocation and would be good candidates for early operative treatment [101].

Surgical Approach / Technique: Operative management for shoulder instability in National Football League athletes is associated with fewer recurrent instability events, greater time between recurrent instability events, and greater career longevity compared to nonoperative treatment [55]. Females undergoing total hip arthroplasty presented with worse baseline conditions and showed relatively less improvement at 1-year postsurgery compared to males [43]. Female patients and patients with non-sports-related ACL tears had less risk of associated intra-articular injuries with delayed surgery [93]. Identification of risk factors for anterior cruciate ligament (ACL) injuries in female athletes provides direction for targeted prophylactic treatment to high-risk individuals [9].

Implant Selection: Fixed-bearing medial unicompartmental knee arthroplasty (UKA) demonstrates low complication rates, good-to-excellent long-term patient outcomes, and satisfactory implant survival in young patients (≤ 60 years) at minimum 10-year follow-up [2]. Pre-existing significant preoperative radiological patellofemoral disease does not affect 10-year implant survival or long-term functional outcomes in fixed-bearing unicompartmental knee arthroplasty [13]. Total knee arthroplasty using patient-specific guides in obese patients shows favorable short-term outcomes [4].

Alignment / Balancing Strategy: The quality of care alone does not fully account for long-term outcomes in knee osteoarthritis, suggesting other factors need to be considered [5].

Pain Management: Clinicians should carefully weigh risk factors when considering surgical and non-surgical approaches for patients at higher risk of inferior surgical outcomes following knee arthroscopic procedures [14].

Adjuncts: Patients undergoing guided growth for knee deformity correction should be closely followed to prevent complications, and stringent patient selection criteria should be followed to ensure success [15].

Setting of Care: Patients contracting COVID-19 between 8 and 30 days after initial presentation for hip fracture are at even higher mortality risk [20]. Patient outcomes, including complication, mortality, and readmission rates, remained unchanged during the pandemic despite restrictions on elective total knee arthroplasty utilization [23]. Demographic and social factors impact the utilization of elective and nonelective primary total hip arthroplasty and subsequent revision surgery [87].

Other Considerations: Surgeons should advise patients about increased risks associated with diabetes mellitus when obtaining informed consent for elective primary total knee replacement and be meticulous about peri-operative care [40].

Complications

Infection (PJI): The provided evidence does not contain specific data regarding infection rates or risk factors for periprosthetic joint infection.

Aseptic loosening: The estimated lifetime risk of revision after primary knee arthroplasty varies depending on patient sex, age, and underlying diagnosis [3].

Instability: The provided evidence does not contain specific data regarding instability rates or risk factors.

Periprosthetic fracture: The provided evidence does not contain specific data regarding periprosthetic fracture rates or risk factors.

Thromboembolism: The provided evidence does not contain specific data regarding thromboembolic events or risk factors.

Patellar / Extensor-mechanism: The provided evidence does not contain specific data regarding patellar or extensor-mechanism complications.

Stiffness / Arthrofibrosis: The provided evidence does not contain specific data regarding stiffness or arthrofibrosis rates or risk factors.

Nerve palsy: The provided evidence does not contain specific data regarding nerve palsies or risk factors.

Wound complications: Complications after high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) are associated with increasing medical comorbidities and tobacco use [71]. There is a higher rate of overall complications observed after DFO compared to the HTO cohort [71].

Polyethylene wear: The provided evidence does not contain specific data regarding polyethylene wear rates or risk factors.

Other Considerations: Advanced age is not associated with adverse postoperative outcomes after high tibial osteotomy (OWHTO) [1]. Cartilage status, rather than age, determines outcomes after OWHTO [1]. Young patients (≤ 60 years) undergoing fixed-bearing medial unicompartmental knee arthroplasty (UKA) have low complication rates at minimum 10-year follow-up [2]. Short-term follow-up shows favorable outcomes for total knee arthroplasty using patient-specific guides in obese patients [4]. Quality of care alone does not fully account for long-term outcomes in knee osteoarthritis [5]. A BMI > 45 kg/m2 is associated with dramatically increased postoperative complications in total knee arthroplasty and total hip arthroplasty [17]. Prediction of moderate and severe frailty independently increases 90-day, 2-year, and 5-year morbidity, mortality, and health care use after total knee arthroplasty [22]. Patient outcomes, including complication, mortality, and readmission rates, remained unchanged during the COVID-19 pandemic despite restrictions on elective total knee arthroplasty [23]. Years of experience is the only factor associated with severe injuries in Chinese Arena Football League players [27]. Age at the time of anterior cruciate ligament reconstruction (ACLR) surgery is a strong risk factor for revision ACLR [28]. Prior total joint replacement (TJR) is a risk factor for subsequent TJR in the contralateral joint [29]. Younger age increases the risk of sustaining multiple concomitant injuries with an ACL rupture [61]. Concomitant injuries with ACL rupture are more prevalent in younger cohorts, potentially resulting in a poorer long-term prognosis [61]. Conventional total knee arthroplasty outcomes are favorable regardless of gender in the Asian population [69]. Younger patients are at increased risk for graft rupture and contralateral injury after ACLR [97]. It remains to be determined whether age per se is a risk factor or if age represents a proxy for other factors regarding graft rupture and contralateral injury after ACLR [97]. Patients with a history of prior cruciate ligament surgery have a substantially higher risk of total knee arthroplasty (TKA) [103]. Patients with a history of prior cruciate ligament surgery undergo arthroplasty at a relatively younger age than individuals without such history [103]. Patients with chronic obstructive pulmonary disease (COPD) undergoing TKA constitute a high-risk population with more complex medical histories [106]. Crude differences in complications and readmissions for COPD patients undergoing TKA were not independent of confounders and diminished over time [106]. Risk factors for early knee osteoarthritis include female sex, ageing, obesity, and history of knee injury [107].

Recovery

The provided evidence does not contain specific data regarding postoperative timelines for light activity, full activity, or complete recovery phases, nor does it detail rehabilitation protocols, functional milestones, or specific time-bound outcomes for the procedures listed. The available data focuses on long-term survival, complication rates, and demographic risk factors rather than the immediate postoperative recovery trajectory.

Other Considerations

Patient Selection & Demographics: Advanced age is not associated with adverse postoperative outcomes after high tibial osteotomy [1]. Cartilage status, rather than age, determines outcomes after high tibial osteotomy [1]. Advanced age should be considered a potential indication for open wedge high tibial osteotomy rather than a risk factor [1]. Fixed-bearing medial unicompartmental knee arthroplasty demonstrates low complication rates in patients aged 60 years or younger at minimum 10-year follow-up [2]. Fixed-bearing medial unicompartmental knee arthroplasty demonstrates good-to-excellent long-term patient outcomes in patients aged 60 years or younger at minimum 10-year follow-up [2]. Fixed-bearing medial unicompartmental knee arthroplasty demonstrates satisfactory implant survival in patients aged 60 years or younger at minimum 10-year follow-up [2]. The estimated lifetime risk of revision knee arthroplasty varies depending on patient sex [3]. The estimated lifetime risk of revision knee arthroplasty varies depending on patient age [3]. The estimated lifetime risk of revision knee arthroplasty varies depending on the underlying diagnosis [3]. Short-term follow-up shows favorable outcomes for total knee arthroplasty using patient-specific guides in obese patients [4]. Quality of care alone does not fully account for long-term outcomes in knee osteoarthritis [5].

Socioeconomic Disparities: Insurance status and income proxies are consistent predictors of disparities in access to care after medial patellofemoral ligament reconstruction [8]. Insurance status and income proxies are consistent predictors of disparities in outcomes after medial patellofemoral ligament reconstruction [8]. Patients with lower insurance status or income experience longer wait times from injury to clinic evaluation for medial patellofemoral ligament reconstruction [8]. Patients with lower insurance status or income have reduced odds of being selected as a candidate for medial patellofemoral ligament reconstruction [8].

Frailty & Morbidity: Prediction of moderate and severe frailty independently increases 90-day morbidity after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 90-day mortality after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 90-day health care use after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 2-year morbidity after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 2-year mortality after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 2-year health care use after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 5-year morbidity after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 5-year mortality after total knee arthroplasty [22]. Prediction of moderate and severe frailty independently increases 5-year health care use after total knee arthroplasty [22].

Specific Procedure Risks: Age at the time of anterior cruciate ligament reconstruction is a strong risk factor for revision anterior cruciate ligament reconstruction [28]. The 2-year short-term functional outcome scores of unicompartmental knee arthroplasty in the octogenarian population do not differ statistically from younger age groups [33]. Osteonecrosis in patients with systemic lupus erythematosus undergoing total knee arthroplasty is not associated with worse outcomes [65]. The neutrally corrected group had better long-term survival compared with the unchanged phenotype group in mechanically aligned total knee arthroplasty in Asian patients with osteoarthritis [72]. Smoking is associated with higher residual pain after autologous osteochondral transplantation for osteochondral lesions of the talus [73]. Smoking is associated with poorer functional outcomes at midterm follow-up after autologous osteochondral transplantation for osteochondral lesions of the talus [73]. There are no significant differences in activity levels based on Tegner scores between smokers and non-smokers after autologous osteochondral transplantation for osteochondral lesions of the talus [73].

Pediatric/Adolescent Considerations: The risk of Osgood-Schlatter disease is greater in stage A tibial tuberosity bony maturity than in stage C [111]. The risk of Osgood-Schlatter disease is greater in stage E tibial tuberosity bony maturity than in stage A [111]. The risk of Osgood-Schlatter disease increases with age in males [111]. The risk of Osgood-Schlatter disease does not increase with age in females [111].

Key Evidence

  • [Commentary] Advanced age should not be identified as a risk factor but rather a potential indication for OWHTO, as cartilage status rather than age determines outcomes. (10.1016/j.arthro.2021.05.042)
  • [L4] The study demonstrates low complication rates, good-to-excellent long-term patient outcomes, and satisfactory implant survival for this age group. (10.1007/s00167-020-05870-4)
  • [L3] The estimated lifetime risk of revision knee arthroplasty varied depending on patient sex, age, and underlying diagnosis. (10.1302/0301-620x.104b12.bjj-2021-1631.r3)
  • [Paper] Short-term follow-up has shown favorable outcomes. (10.1007/s00402-015-2399-z)
  • [L4] However, the quality of care alone does not fully account for longterm outcomes, suggesting that other factors need to be considered. (10.1186/s12891-025-08524-z)
  • [L3] However, a small subset of higher-risk patients still requires nonhome discharge and experience worse outcomes. (10.5435/jaaos-d-23-01242)
  • [L3] Patients with an NHFS ≥ six should be considered 'higher risk', though this requires validation by other studies. (10.1302/0301-620x.97b1.34670)
  • [L4] Patients with these characteristics experience longer wait times from injury to clinic evaluation and have reduced odds in selection as a candidate for surgery. (10.1016/j.asmr.2025.101268)
  • [L4] Identification of these risk factors provides direction for targeted prophylactic treatment to high-risk individuals. (10.1177/0363546505284183)
  • [L4] This protocol describes a prospective community-based cohort study designed to examine the natural history of recent-onset knee pain, identify phenotypes, and determine associated risk factors through baseline and longitudinal assessments up to Year 3. (10.1186/s12891-017-1761-4)
  • [L3] Individuals reporting at least 1 previous undiagnosed concussions exhibited worse baseline clinical indicators. (10.1177/03635465221118089)
  • [L2] Presentation factors that increase the likelihood of a diagnostic X-ray included pain for longer than 6 months, the presence of medial or diffuse pain, and mechanical symptoms. (10.1007/s00167-014-3003-8)
  • [L3] The presence of significant preoperative radiological patellofemoral disease does not affect long-term implant survival and patients have excellent functional outcomes 10 years postoperatively. (10.1007/s00167-018-5169-y)
  • [L3] For patients who are at higher risk of inferior surgical outcomes, clinicians should carefully weigh risk factors when considering surgical and non-surgical approaches. (10.1007/s00167-022-06919-2)
  • [L4] Patients should be closely followed to prevent complications, and stringent patient selection criteria should be followed to ensure success. (10.1186/s13018-021-02304-w)
  • [L3] Using BMI alone to determine eligibility criteria did not improve the rate of clinically meaningful improvements. (10.1302/0301-620x.102b6.bjj-2019-1644.r1)
  • [L3] The odds of complications increased dramatically once BMI reached 45.0 kg/m2. (10.1016/j.arth.2015.10.042)
  • [L2] The cohort is unique in its size, setting, and range of age and type of knee complaints. (10.1186/1471-2474-6-45)
  • [L5] Experts identified a large number of characteristics for describing patients with knee osteoarthritis. (10.1186/1471-2474-14-369)
  • [L2] Those contracting infection between 8 and 30 days after initial presentation are at even higher mortality risk, signalling the potential for targeted interventions during this period to improve survival. (10.1302/0301-620x.104b10.bjj-2022-0082.r1)
  • [L3] Prediction of moderate and severe frailty independently increased 90-day, 2-year, and 5-year morbidity, mortality, and health care use. (10.1016/j.arth.2026.02.006)
  • [L3] Patient outcomes were not compromised despite pandemic restrictions, as complication, mortality, and readmission rates remained unchanged. (10.5435/jaaos-d-22-00193)
  • [L1] The vast majority of RCTs (>85%) did not enroll patients based on disease severity, as measured by PROM score thresholds or radiographic classifications, in their inclusion criteria. (10.2106/jbjs.23.00629)
  • [L5] Measures of disease frequency such as prevalence and incidence and measures of association such as relative risk and odds ratios are basic tools that help us to quantify the relationship between exposures to risk factors and diseases or injuries. (10.1177/036354659702500325)
  • [L2] Years of experience was the only factor that was associated with severe injuries. (10.1177/2325967118780040)
  • [L2] Age at the time of ACLR surgery is a strong risk factor for revision ACLR. (10.1177/0363546515614813)
  • [L2] The observation that prior TJR is a risk factor for subsequent TJR in the contralateral joint has not been described previously. (10.1186/s12891-016-0864-7)
  • [L3] Both surgical approaches yielded comparable clinical outcomes and complication rates across all age groups. (10.1186/s12891-024-08023-7)
  • [L1] There is currently no evidence that obesity should be considered a definite contraindication to UKA. (10.1007/s00167-020-06297-7)
  • [L4] Sex- and age-related differences exist among diagnoses and injury mechanisms that involved ED visits. (10.1177/23259671251399846)
  • [L3] The 2-year short-term functional outcome scores of UKA in the octogenarian population did not differ statistically from the younger age groups. (10.1007/s00167-017-4639-y)
  • [L3] The overall patient health status improved from 2008 to 2018, with improvement in modifiable comorbidities, functional status, and overall morbidity and mortality probability, while no clinically relevant change was observed in patient age, BMI, or specific non-modifiable comorbidities. (10.2106/jbjs.20.00597)
  • [L3] Standardized preoperative protocols should be developed and instituted to improve outcomes in this patient cohort. (10.5435/jaaos-d-22-00214)
  • [L2] Certain sociodemographic variables (e.g. ethnicity/race, education, income, age) may contribute to an increased risk of experiencing greater pain. (10.1186/s12891-021-04284-8)
  • [L3] Certain variables were associated with increased symptoms across multiple clusters and may be indicative of greater injury severity, while other factors were associated with a more specific symptom presentation. (10.1177/23259671231163581)
  • [L4] Our findings indicate that MVPA could potentially increase knee dimensions through similar biomechanical mechanisms it affects diaphyseal morphology, thus offering a potential target in reducing tissue strains and preventing knee problems. (10.1186/s12891-022-05475-7)
  • [L4] The most common injury mechanism occurred without contact with the knee in extension during a deceleration or momentum shift, with resultant valgus and rotational force across the knee. (10.1016/j.arthro.2024.03.047)
  • [L1] Surgeons should advise patients specifically about these increased risks when obtaining informed consent and be meticulous about their peri-operative care. (10.1302/0301-620x.96b12.34378)
  • [L1] Females have higher rates of postoperative complications and revision surgery. (10.1016/j.jse.2024.12.043)
  • [L5] The report highlights that while many concussions are mild, they are a form of traumatic brain injury with a wide range of severity, and early detection through thorough knowledge of signs and symptoms is critical for management. (10.1177/03635465990270052401)
  • [L3] THA remains an effective treatment for severe hip osteoarthritis, but females presented with worse baseline conditions and showed relatively less improvement at 1-year postsurgery compared to males. (10.1002/ksa.12124)
  • [L4] Neck pain in elderly men is common but symptoms and morbidity vary. (10.1186/s13018-023-03508-y)
  • [L2] Using waveforms, instead of discrete peak values of the knee abduction moment, may better represent risky movement patterns. (10.1002/ksa.12471)
  • [L2] These findings underscore the importance of sex-specific preoperative counselling and postoperative management for patients at higher risk of suboptimal outcomes. (10.1002/ksa.12744)
  • [L3] This information is being used to further understand the pathology of OCD, including its cause, associated comorbidities, and initial presentation and symptoms. (10.1177/03635465211057103)
  • [L2] Simpler methods using MRIs downgraded to a clinical-grade resolution can identify the same knee anatomic factors previously found to significantly contribute to ACL injury risk using sophisticated methods and research-grade resolution MRIs. (10.1177/03635465211024249)
  • [L3] Surgical incidence after MRI was likely appropriately lower for older patients. (10.1177/23259671211052560)
  • [L3] Concussions were the most common injury diagnosis, had the worst return-to-play outcomes among common diagnoses, and were mostly sustained outside of competition. (10.1177/23259671221110208)
  • [L4] Patients with more severe imaging lesions tend to have poorer ROM. (10.1186/s12891-023-06432-8)
  • [L1] On the other hand, non-operative treatment with optional delayed ACLR may be the more cost-effective strategy in the middle age population with moderate activity levels. (10.1007/s00167-022-07087-z)
  • [L5] Women exhibited lower knee stiffness in response to low magnitudes of applied torque compared to men and demonstrated an increase of joint stiffness as the magnitude of applied torque increased. (10.1177/0363546508317411)
  • [L3] Whereas nonoperative treatment is associated with faster return to play, operative management is associated with fewer recurrent instability events, greater time between recurrent instability events, and greater career longevity. (10.1016/j.arthro.2020.12.225)
  • [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] Dual task conditions during single-leg drop landing increased maximum internal tibial rotation angle and anterior tibial translation compared to single task conditions, suggesting that neurocognitive load disturbs balance and alters knee biomechanics. (10.1186/s40634-019-0170-z)
  • [Letter] The authors conclude that while the introduced noninvasive device has limitations, it is a useful and valuable tool to investigate preoperative and postoperative influences on tibiofemoral rotation and provides additional objective information on knee kinematics in a simple, reproducible manner. (10.1177/0363546510376622)
  • [L2] SRH, ASA classification and comorbidity count showed increasing risks of medical complications and death with decreasing health status. (10.1186/s12891-025-08745-2)
  • [L3] The observed high-risk knee morphology at an earlier age preliminarily suggests the potential of knee anatomy measurements in identifying those with a predisposition toward ACL injury. (10.1177/03635465231177465)
  • [L2] However, these injuries are more prevalent in the younger cohort potentially resulting in a poorer long-term prognosis. (10.1007/s00167-021-06538-3)
  • [L2] Knee motion and knee loading during a landing task are predictors of anterior cruciate ligament injury risk in female athletes. (10.1177/0363546504269591)
  • [L4] No significant associations were observed between pain catastrophizing and objective knee function (range of motion and muscle strength) or knee biomechanics during gait in patients with severe knee OA. (10.1186/s12891-025-08993-2)
  • [L3] Longer-term durability of TKA in these patients requires further study. (10.1016/j.arth.2026.03.073)
  • [L2] However, conservative management should be considered before surgical treatment is indicated. (10.1186/s13018-022-03376-y)
  • [L3] Therapy with zoledronic acid did not reduce all-cause mortality in this cohort. (10.1186/s12891-022-05880-y)
  • [L2] Overall, this study provides protective clinical parameters as well as quantitative and semi-quantitative MR-imaging parameters associated with maintaining radiographically normal knee joints in an older population over 8 years. (10.1186/s12891-024-07590-z)
  • [L3] A low radiological severity of osteoarthritis was not associated with pain 12 months postoperatively. (10.1302/0301-620x.96b11.33726)
  • [L3] HTO and DFO have substantial complication rates in the short and mid term, with a higher rate of overall complications observed after DFO as compared to the HTO cohort. (10.1007/s00167-022-06865-z)
  • [L3] The neutrally corrected group had better long-term survival compared with the unchanged phenotype group. (10.1302/0301-620x.106b5.bjj-2023-1110.r1)
  • [L3] However, smoking is associated with higher residual pain and poorer functional outcomes at midterm follow-up, despite no significant differences in activity levels based on Tegner scores. (10.1186/s13018-025-06428-1)
  • [L3] Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management. (10.1007/s00167-018-5201-2)
  • [L4] The kinematics of the dominant and nondominant legs of female soccer players in a single-leg DVJ differ in knee valgus angle. (10.1177/03635465221107388)
  • [L4] Independent predictors of complications include patients with high ASA classification, dependent functional status, renal comorbidities, and a recent history of wound infection. (10.1016/j.arthro.2016.01.017)
  • [L3] Rather, PFP may derive from a combination of physical activity in the context of pathological kinematics. (10.1177/0363546516679139)
  • [L4] We compared it against previously published data for radiographic and magnetic resonance imaging sizing techniques and found it to produce results that were, overall, slightly more accurate. (10.1016/j.arthro.2009.01.004)
  • [L4] The header DVJ task showed kinetic and kinematic parameters that suggested increased risk of ACL injury as compared with the standard DVJ task. (10.1177/23259671231164706)
  • [L4] Additionally, functional knee phenotypes varied significantly across geographic regions. (10.1002/ksa.12693)
  • [L2] Advanced age, female sex, overweight, less range of motion, and Kellgren and Lawrence grade 1 at baseline were associated with an increased risk of incident radiographic knee osteoarthritis. (10.1186/s13018-021-02577-1)
  • [L1] There are substantial differences in reported prevalence rates on UEDs, mainly due to the absence of a universally accepted way of labelling or defining UEDs. (10.1186/1471-2474-7-7)
  • [L5] A complete understanding of the forces and risk factors associated with noncontact ACL injury should lead to the development of improved preventive strategies for this devastating injury. (10.5435/00124635-201009000-00003)
  • [L2] Radiographic measurements of severity have a relatively small influence on EOSQ scores. (10.2106/jbjs.20.00819)
  • [L4] The prevalence of specific injury types varied by competition level, match result, and match winners versus losers. (10.1177/2325967121991560)
  • [L3] Demographic and social factors impact the utilization of elective and nonelective primary THA and subsequent revision surgery. (10.1016/j.arth.2023.01.011)
  • [L3] Identifying biomechanical mechanisms that place young athletes at risk for hip injury enables anticipatory guidance and preventative strategies for these patients. (10.1177/2325967113s00059)
  • [L3] Of patients treated nonoperatively for 1 year after ACL tears, 32% underwent delayed ACL reconstruction. (10.1177/0363546516630751)
  • [L4] Severe injury rates and patterns varied by sport, gender, and type of exposure. (10.1177/0363546509333015)
  • [L5] Although the failure load of the posterior portion decreased significantly in the knee flexion position, it plays a significant role against anterior tibial load in the knee extension position. (10.1186/s13018-021-02676-z)
  • [L5] The mechanical data demonstrated that the accompanying localized incongruity involved the onset of biomechanical abnormality consistent with causing cartilage degeneration. (10.1002/jor.21259)
  • [L3] Female patients and patients with non-sports-related ACL tears had less risk of associated injuries with delayed surgery. (10.1177/23259671211073905)
  • [L3] The demographic subsets that are most at risk for increased incidence of associated injuries with surgical delay were males, adults between 26 and 39 years old, overweight individuals, and those whose ACL tears occurred while playing sports. (10.1016/j.arthro.2017.04.104)
  • [L3] Significant diversity in patient, injury, and surgical factors exist among large prospective cohorts collected in different locations. (10.1007/s00167-009-0919-5)
  • [L3] Whether age per se is a risk factor or age represents a proxy for other factors remains to be determined. (10.1177/0363546513517540)
  • [L2] Nonoperative treatment of ACL injuries failed in 60% of patients and was highly correlated with age and activity level. (10.1177/0363546520917386)
  • [L2] Bilateral knee osteoarthritis is very common with time, as the majority of sufferers will eventually develop radiographic disease in both knees. (10.1186/1471-2474-13-153)
  • [L3] This multivariable model can identify patients who are at high risk for recurrent dislocation and would be good candidates for early operative treatment. (10.2106/jbjs.20.00020)
  • [L3] Patients with a history of prior cruciate ligament surgery have substantially higher risk of TKA and undergo arthroplasty at a relatively younger age than individuals without a history of prior cruciate ligament surgery. (10.1302/0301-620x.106b3.bjj-2023-0425.r2)
  • [L3] Patients with COPD undergoing TKA constitute a high-risk population with more complex medical histories, but crude differences in complications and readmissions were not independent of confounders and diminished over time. (10.1016/j.arth.2026.03.037)
  • [L4] The risk factors for early knee osteoarthritis were female sex, ageing, obesity, and history of knee injury. (10.1007/s00167-019-05614-z)
  • [L3] The risk of OSD is greater in stage A than stage C and in stage E than stage A, with the risk increasing with age in males but not in females. (10.1177/2325967117749184)

See Also

References

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[103] Environmental and genetic risk factors associated with total knee arthroplasty following cruciate ligament surgery. The Bone & Joint Journal. 2024. DOI: 10.1302/0301-620x.106b3.bjj-2023-0425.r2

[106] Impact of Chronic Obstructive Pulmonary Disease on Complications and Readmissions Following Total Knee Arthroplasty: A Retrospective Matched Cohort Study. The Journal of Arthroplasty. 2026. DOI: 10.1016/j.arth.2026.03.037

[107] Early knee osteoarthritis prevalence is highest among middle-aged adult females with obesity based on new set of diagnostic criteria from a large sample cohort study in the Japanese general population. Knee Surgery, Sports Traumatology, Arthroscopy. 2019. DOI: 10.1007/s00167-019-05614-z

[111] Bony Maturity of the Tibial Tuberosity With Regard to Age and Sex and Its Relationship to Pathogenesis of Osgood-Schlatter Disease: An Ultrasonographic Study. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967117749184

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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.