Definition Of Knee Osteoarthritis Research Articles

Health-related quality of life in relation to symptomatic and radiographic definitions of knee osteoarthritis: data from Osteoarthritis Initiative (OAI) 4-year follow-up study

BackgroundThe purpose was to quantify the decrement in health utility (referred as disutility) associated with knee osteoarthritis (OA) and different symptomatic and radiographic uni- and bilateral definitions of knee OA in a repeated measures design of persons with knee OA or at increased risk of developing knee OA.MethodsData were obtained from the Osteoarthritis Initiative database. SF-12 health-related quality of life was converted into SF-6D utilities, and were then handled as the health utility loss by subtracting 1.000 from the utility score, yielding a negative value (disutility). Symptomatic OA was defined by radiographic findings (Kellgren-Lawrence, K-L, grade ≥ 2) and frequent knee pain in the same knee. Radiographic OA was defined by five different definitions (K-L ≥ 2 unilaterally / bilaterally, or the highest / mean / combination of K-L grades of both knees). Repeated measures generalized estimating equation (GEE) models were used to investigate disutility in relation to these different definitions.ResultsUtility decreased with worsening of symptomatic or radiographic status of knee OA. The participants with bilateral and unilateral symptomatic knee OA had 0.03 (p < 0.001) and 0.02 (p < 0.001) points lower utility scores, respectively, compared with the reference group. The radiographic K-L grade 4 defined as the mean or the highest grade of both knees was related to a decrease of 0.04 (p < 0.001) and 0.03 (p < 0.001) points in utility scores, respectively, compared to the reference group.ConclusionsKnee OA is associated with diminished health-related quality of life. Health utility can be quantified in relation to both symptomatic and radiographic uni- and bilateral definitions of knee OA, and these definitions are associated with differing disutilities. The performance of symptomatic definition was better, indicating that pain experience is an important factor in knee OA related quality of life.

An experimental study on knee osteoarthritis patients

The prevalence of knee osteoarthritis is much lower in Asians or in black people. Few population-based studies regarding the incidence of knee osteoarthritis were found, with the incidence of knee osteoarthritis being higher in different age group. However, strict comparisons among these studies are limited, because the definition of the incidence of knee osteoarthritis is not the same for each study. A few risk factors for knee osteoarthritis were established, such as female gender and obesity. Also several cross sectional studies have found that the presence of a previous knee injury is significantly associated with the incidence of knee osteoarthritis. One of the limitations in previous studies is the definition of knee osteoarthritis. The most popular grading system for knee osteoarthritis is Kellgren–Lawrence classification. The data for the study was undertaken to determine osteoarthritis among the population in Chennai, Tamil Nadu, India. Frequencies and percentages were calculated to find the prevalence of osteoarthritis. For the purpose of the study a total of 207 female subjects aged (30-80) were engaged. The present study reports that the knee osteoarthritis among the sedentary women of the subjects were found to have a significant level (p

Knee osteoarthritis and the risk of premature mortality in the community: An international individual patient level meta-analysis in 9889 subjects

Purpose: The rising prevalence of osteoarthritis (OA) is recognised has having an impact on the increased need for medical consultations due to pain and functional limitations; however, the effect of OA on mortality is less understood. A recent systematic review has shown that there is currently mixed evidence on the relationship between lower limb OA and all-cause mortality, largely due to heterogeneity in definitions of OA, confounders, and inclusion criteria. The aim of this research was to combine individual patient data (IPD) from major international population-based cohorts using harmonised OA data, and to assess whether subjects with knee OA have an increased association with premature mortality. Methods: General population OA cohort studies were identified by literature review and expert consultation, regardless of whether they had published on the relationship between OA and mortality. Six population-based cohorts and one enhanced risk factor cohort* were identified and available for analysis: three US cohorts (Framingham, Johnston County Osteoarthritis Project and Multicentre Osteoarthritis Study* (MOST)); one UK cohort (Chingford); a Dutch cohort (Rotterdam Study); and an Australian cohort (Tasmanian Older Adult Cohort (TasOAC)). The definition of knee OA was established via an expert consensus study, which selected the two OA variables used in this analysis. Radiographic OA (ROA) was defined as Kellgren and Lawrence (K/L) grade 2 ≥ or equivalent validated scoring methods (e.g. the OARSI atlas). Pain was defined by using either an NHANES-type question (i.e. ‘have you had pain for most days in the last month in your joint’), the WOMAC pain subscale, or alternative equivelent pain question. Subjects were divided into four categories: (1) No OA (ROA-/Pain-); (2) ROA only (ROA+/Pain-); (3) Symptomatic OA (ROA-/Pain+); (4) Symptomatic Radiographic OA (ROA+/Pain+). Included subjects were free from RA, aged 45–80 years old, had complete symptomatic and radiographic OA data, confounder data (age, sex, and race) and mortality data. Complete case analysis was undertaken for all cohorts due to the low level of missingness (<10%). The association between OA and the time to all-cause mortality was assessed using Cox proportional hazard regression models to estimate hazard ratios (HRs) and 95% confidence intervals. Symptomatic radiographic OA (SROA) was assessed by comparing subjects who were ROA+/Pain+ against subjects free from OA (ROA-/Pain-). Symptomatic OA (SOA) compared subjects who were ROA-/Pain+ against ROA-/Pain- subjects. IPD meta-analysis methods were utilised, using a two-stage approach. Individual studies were analysed separately using identical methods and then data was pooled in the second stage using random effects analysis, with Dersimonian and Laird estimation. Heterogeneity was assessed using I-squared and the tau-squared statistic, and uncertainty around tau was accounted for by producing confidence intervals around the pooled estimate using the Hartung-Knapp correction. Results: The number of baseline subjects with complete data ranged from 253 to 3384 in each cohort, totalling 9889 subjects ranging from a median follow-up of 5.6 to 19.8 years. Prevalence of knee SROA ranged from 4.4% in one of the youngest cohorts (Chingford) to 33.3% in the risk enriched MOST cohort. Subjects with SROA had an overall pooled estimate of HR 1.47 (95% CI 1.07, 2.04) in an unadjusted model, with a pooled estimate of HR 1.19 (95% CI 1.04, 1.37) when adjusted for potential confounding factors (figure 1). Subjects with SOA had an overall pooled estimate of HR 1.13 (95% CI 0.70, 1.81) in an unadjusted model, with a pooled estimate of HR 1.19 (95% CI 0.78, 1.81) in the adjusted model (figure 2). Conclusions: Subjects with knee SROA had a 19% increased association with premature death independent of age, sex and race compared to pain-free and ROA-free subjects. This increase was not found in subjects with pain alone (SOA). This international study is one of the largest analyses of well-phenotyped knee osteoarthritis and mortality in the general population.

Association of knee pain and different definitions of knee osteoarthritis with health-related quality of life: a population-based cohort study in southern Sweden

BackgroundWhile the impact of knee pain and knee osteoarthritis (OA) on health-related quality of life (HRQoL) has been investigated in the literature, there is a lack of knowledge on the impact of different definitions of OA on HRQoL. The main aim of this study was to measure and compare the impact of knee OA and its different definitions on HRQoL in the general population.MethodsA random sample of 1300 participants from Malmö, Sweden with pain in one or both knees in the past 12 months with duration ≥4 weeks and 650 participants without were invited to clinical and radiographic knee examination. A total of 1527 individuals with a mean (SD) age 69.4 (7.2) participated and responded to both generic (EQ-5D-3L) and disease-specific (the Knee injury and Osteoarthritis Outcome Score) questionnaires. Knee pain was defined as pain during the last month during most of the days. Knee OA was defined radiographically (equivalent to Kellgren and Lawrence grade ≥2) and clinically according to the American College of Rheumatology (ACR) criteria.ResultsOf participants with either knee pain or knee OA or both, 7 % reported no problem for the EQ-5D-3L attributes. The corresponding proportion among references (neither knee pain nor OA) was 42 %. The participants with knee pain and OA had all HRQoL measures lower compared to those with knee pain but no OA. The ACR clinical definition of knee OA was associated with lower HRQoL than the definition based on radiographic knee OA (adjusted difference −0.08 in UK EQ-5D-3L index score).ConclusionsApplying different definitions of knee OA result in different levels of HRQoL and this is mainly explained by the knee pain experience. These differences may lead to discrepant conclusions from cost-utility analyses.

Association of knee pain and different definitions of knee osteoarthritis with health-related quality of life: A population-based cohort study

Association of knee pain and different definitions of knee osteoarthritis with health-related quality of life: A population-based cohort study

What Are the Prognostic Factors for Radiographic Progression of Knee Osteoarthritis? A Meta-analysis.

BackgroundA previous systematic review on prognostic factors for knee osteoarthritis (OA) progression showed associations for generalized OA and hyaluronic acid levels. Knee pain, radiographic severity, sex, quadriceps strength, knee injury, and regular sport activities were not associated. It has been a decade since the literature search of that review and many studies have been performed since then investigating prognostic factors for radiographic knee OA progression.Questions/purposesThe purpose of this study is to provide an updated systematic review of available evidence regarding prognostic factors for radiographic knee OA progression.MethodsWe searched for observational studies in MEDLINE and EMBASE. Key words were: knee, osteoarthritis (or arthritis, or arthrosis, or degenerative joint disease), progression (or prognosis, or precipitate, or predictive), and case-control (or cohort, or longitudinal, or follow-up). Studies fulfilling the inclusion criteria were assessed for methodologic quality according to established criteria for reviews on prognostic factors in musculoskeletal disorders. Data were extracted and results were pooled if possible or summarized according to a best-evidence synthesis. A total of 1912 additional articles were identified; 43 met our inclusion criteria. The previous review contained 36 articles, thus providing a new total of 79 articles. Seventy-two of the included articles were scored high quality, the remaining seven were low quality.ResultsThe pooled odds ratio (OR) of two determinants showed associations with knee OA progression: baseline knee pain (OR, 2.38 [95% CI, 1.74–3.27) and Heberden nodes (OR, 2.66 [95% CI, 1.46–8.84]). Our best-evidence synthesis showed strong evidence that varus alignment, serum hyaluronic acid, and tumor necrosis factor-α are associated with knee OA progression. There is strong evidence that sex, former knee injury, quadriceps strength, smoking, running, and regular performance of sports are not associated with knee OA progression. Evidence for the majority of determined associations, however, was limited, conflicting, or inconclusive.ConclusionsBaseline knee pain, presence of Heberden nodes, varus alignment, and high levels of serum markers hyaluronic acid and tumor necrosis factor-α predict knee OA progression. Sex, knee injury, and quadriceps strength, among others, did not predict knee OA progression. Large variation remains in definitions of knee OA and knee OA progression. Clinical studies should use more consistent definitions of these factors to facilitate data pooling by future meta-analyses.Electronic supplementary materialThe online version of this article (doi:10.1007/s11999-015-4349-z) contains supplementary material, which is available to authorized users.

Elucidation of Dietary Risk Factors in Osteoarthritis Knee—A Case-Control Study

Background and Objective: Nutritional imbalance, combined with endocrine abnormalities, may be involved in the pathogenesis of osteoarthritis (OA). This study was conducted to determine the association of OA with dietary factors, such as quantity and quality of nutrient intake.Methods: This case-control study enrolled 180 knee osteoarthritis (KOA) subjects who met the American College of Rheumatology definition of KOA, with an equal number of matched controls. Outcome measures, such as dietary nutrient intake and its frequency, were recorded using a food frequency questionnaire.Results: Compared to controls, cases were older individuals with a higher body mass index (BMI). Physical activity scores were lower in female cases compared to male cases and controls. A significantly higher intake of phosphorus and fat was observed in overall cases (fat in females only). A significantly lower intake of vitamin C and vitamin D was observed in overall cases and the significance of vitamin D persisted on gender-wise bifurcation. On multiple logistic regression analysis, the intake of vitamin D (odds ratio [OR] = 0.79) and vitamin C (OR = 0.97) was inversely associated with the presence of KOA in the observation group, especially in females. Generally, the intake of food servings/day, green leafy vegetables (GLVs), and fats/oils was higher, whereas the intake of fruits, milk/milk products, and meat/poultry was lower in cases compared to controls.Conclusion: Low intake of vitamin D and vitamin C is a possible risk factor for KOA. Certain food groups, such as fruits, milk/milk products, and meat/poultry are beneficial for KOA. Further studies are needed to elucidate the associations between diet and KOA.

Do scores on WOMAC pain and function subscales vary with different definitions of knee osteoarthritis?

Purpose: The MRI definition for knee osteoarthritis, developed in 2011, has not yet been validated in other populations. In previous work, we showed that if this MRI definition of tibiofemoral (TF) OA (TFOAMRI) is applied, more cases of knee OA are detected than with the radiographic Kellgren and Lawrence grading (K&L). With a better content validity and at least equal construct validity, we concluded that the TFOAMRI is more sensitive in detecting structural knee OA. However, it is unknown whether women defined with TFOAMRI differ in pain and disability from those who are not, or those who have a radiographic K&L grade ≥2. Furthermore, with the available MRI definitions, a distinction between patellofemoral (PF) OA and TFOA can be made, and the debated contribution to pain and disability by PFOA can be assessed. Therefore the aim of the present study was to investigate if women with knee OA defined with PF- or TFOAMRI report different pain and function scores measured with The Western Ontario and McMaster Universities Arthritis Index (WOMAC), or report different scores than women with knee OA defined by K&L-grading. Methods: Of 891 females (aged 45-60) from a random subpopulation of the Rotterdam Study, radiographs and MRI of both knees were assessed for knee OA; radiographs with the K&L-grading (K&L≥2 was defined as OA) and MRIs with a comprehensive semi-quantitative scoring system. Based on these scored features we applied the proposed MRI definition. We distinguished a PFOAMRI-definition from a TFOAMRI-definition. All women filled in the WOMAC questionnaire. With multivariable regression analysis we tested if the definitions (K&L≥2, PFOAMRI or TFOAMRI) reported different WOMAC pain and function scores independently from each other. Analyses were adjusted for BMI, age and bilaterality (if women had knee OA in one or both knees). Results: Data of 871 women were analyzed. Of 20 women data was missing due to insufficient quality of images (radiographs or MRIs). Table 1 shows the mean and the standard deviation (sd) of age, BMI, WOMAC pain and function scores per definition. 21 women met the K&L≥2 and TFOAMRI definition in one or both knees; 3 women met the K&L≥2 and PFOAMRI definitions; 35 women met the TF- and PFOAMRI definitions; 17 women met all three definitions of knee OA in one or both knees. All three definition contributed significantly (p < 0.001) to higher WOMAC pain scores (K&L≥2: β = 1.61; (95% confidence interval (95% CI) 0.79–2.44), PFOAMRI: β = 1.32 (95% CI: 0.69–1.95) or TFOAMRI: β = 1.15 (95% CI: 0.52–1.77)) and to WOMAC function score (K&L≥2: β = 5.21 (95% CI:2.56–7.86), p < 0.001; TFOAMRI (β = 2.75 (95% CI:0.74–4.75), p = 0.007; PFOAMRI: β = 4.06 (2.02–6.10), p < 0.001). Conclusions: The MRI definitions show differences in WOMAC pain and function scores between women with and without knee OA. Those women with all definitions positive had the highest pain and disability scores, and those with alone K&L≥2 the lowest. The TF- and PFOAMRI definitions, but also the K&L-definition, all contributed significantly and independently from each other, to the higher pain and disability scores.Table 1Mean (sd) of age, BMI, WOMAC pain (0-20) and function subscale (0-68)Women met the definition (n)Age mean (sd)BMI mean (sd)Uni-/bilateral n/nWOMAC pain mean (sd)WOMAC function mean (sd)No OA67654.6 (3.8)26.3 (4.3)-1.0 (2.4)3.0 (7.5)K&L≥26156.2 (3.3)30.1 (6.3)25/364.2 (4.7)12.9 (16.1)- Only K&L≥21756.1 (3.8)27.1 (3.3)11/61.8 (2.3)5.7 (8.2)- K&L≥2 + TFOAMRI2155.7 (3.4)30.1 (7.2)7/143.8 (4.9)11.8 (17.6)- K&L≥2 + PFOAMRI357.5 (1.3)34.8 (7.7)0/35.7 (6.4)21.3 (25.3)TFOAMRI12556.6 (3.3)29.4 (6.2)69/563.5 (4.7)10.3 (14.7)- Only TFOAMRI5155.9 (3.6)27.7 (6.2)42/92.2 (3.4)7.0 (11.2)PFOAMRI10656.9 (2.9)30.1 (4.1)59/473.5 (4.6)10.6 (14.4)- Only PFOAMRI5156.1 (2.9)29.2 (4.1)40/112.3 (3.4)8.2 (11.7)- TF- + PFOAMRI3557.7 (2.8)29. (5.8)15/203.5 (5.1)8.9 (14.0)K&L≥21757.3 (2.6)32.4 (6.6)4/136.7 (5.2)19.2 (17.6) Open table in a new tab

English

Introduction The prevalence of knee osteoarthritis is much higher in Caucasians than in Asians or in black people. Few population-based studies regarding the incidence of knee osteoarthritis were found, with the incidence of knee osteoarthritis being higher in Japanese than in Caucasians. However, strict comparisons among these studies are limited, because the definition of the incidence of knee osteoarthritis is not the same for each study. A few risk factors for knee osteoarthrit is were established, such as female gender and obesity. Several crosssectional studies have found that the presence of a previous knee injuryis significantly associated with the incidence of knee osteoarthritis, but longitudinal studies did not find this significant correlation. However, the same longitudinal studies found significant associations between previous knee injuries and incident knee pain. One of the limitations in previous studies is the definition of knee osteoarthritis. The most popular grading system for knee osteoarthritis is Kellgren–Lawrence classification. However, joint space narrowing and osteophytosis cannot be separately assessed in this grading system. Recent studies have suggested distinct causes for both joint space narrowing and osteophytosis. These studies have also found an independent association between joint space narrowing and osteophytosis with the quality of life of the person. This is a review of population-based studies for knee osteoarthritis. Conclusion To further assess new risk factors or markers, joint space narrowing and osteophytosis should be assessed separately using a fully automatic system that measures joint space width and osteophyte area. Introduction Knee osteoarthritis (OA) is a major public health issue and causes chronic pain and disability among elderly in most of the developed countries. It is characterised by several pathological features, including joint space narrowing and osteophytosis. Despite the urgent need of strategies for the prevention and treatment of this condition, demographics on the overall disease prevalence and the affected subgroups are not adequately characterised yet. The reported prevalence of radiographic knee OA differs considerably among previous population-based epidemiologic studies.In addition, apart from age, sex, obesity and occupational activities, there are only a few other established risk factors for knee OA. We aimed to review the literature on population-based studies investigating knee OA. Prevalence of knee osteoarthritis Twelve previously published studies on the prevalence of knee OA were identified after performing a search in the English literature1–12 (Table 1). Epidemiologic studies on elderly Caucasians in the United States and Europe have shown that the prevalence of knee OA with Kellgren– Lawrence(KL) grade 2 or higher was 30–40%; where as studies in Asia have found a prevalence of 60% or higher. Thus, the prevalence of knee OA is higher in Asian populations than in Caucasian populations. Based on these studies, Caucasians show a lower prevalence of radiographic OA than that found in other races. Furthermore, the Johnston County study and the National Health and Nutrition Examination Survey (NHANES) studies reported that African-Americans have a higher prevalence of radiographic knee OA than did Caucasians. However, in the NHANES studies, the prevalence rates of knee OA were lower than those in other studies;this discrepancy was explained by differences in radiographic acquisition. In these studies, knee radiographs were obtained in a non-weight-bearing position, as opposed to other studies, where in knee radiographs were obtained in a weight-bearing position. The Chingford study presented lower prevalence of knee OA because subjects were much younger than those who participated in other studies. In terms of KL grading, KL grade 2 indicates the presence of osteophyte formation; and grade 3 indicates joint space narrowing in addition to osteophyte formation; KL ≥ 2 is generally thought to be the standard for the diagnostic criterion of knee OA13. However, accumulating evidence has shown that osteophytosis and joint space narrowing have distinct aetiologic mechanisms, and their progression is neither constant nor proportional14. Hence, to assess these two pathological features separately, the * Corresponding author Email: murakis-ort@h.u-tokyo.ac.jp 1 Department of Clinical Motor System Medicine, 22nd Century Medical and Research Center, Faculty of Medicine, University of Tokyo,7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8655, Japan 2 Department of Orthopaedic Surgery, Faculty of Medicine, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8655, Japan 3 Department of Joint Disease Research, 22nd Century Medical & Research Center, Faculty of Medicine, University of Tokyo,7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8655, Japan

Association Between Cumulative Joint Loading From Occupational Activities and Knee Osteoarthritis

To determine the associations between cumulative occupational physical load (COPL) and 3 definitions of knee osteoarthritis (OA). Cross-sectional analyses were performed from 2 population-based cohorts (n = 327). Eligible symptomatic participants were those with pain, aching, or discomfort in or around the knee on most days of a month at any time in the past and any pain in the past 12 months. Asymptomatic participants responded "no" to both knee pain questions. Self-reported COPL was calculated over each participant's lifetime and then categorized into quarters (QCOPL). Radiographic OA (ROA) and symptomatic OA (SOA) were defined by Kellgren/Lawrence grade ≥2, with SOA also including pain. Magnetic resonance imaging (MRI) OA was defined using criteria by Hunter et al. Logistic regression, adjusted with population weights, examined the associations between QCOPL and each of ROA, SOA, and MRI-OA after controlling for covariates and two-way interactions. Participants had a mean ± SD age of 58.5 ± 11.0 years and a mean ± SD body mass index of 26.3 ± 4.7 kg/m(2) . Of those, 109 (33.3%) had ROA, 102 (31.2%) had SOA, and 131 (40.1%) had MRI-OA. Compared with QCOPL-1, increased odds of ROA were found for QCOPL-4 (odds ratio [OR] 3.15, 95% confidence interval [95% CI] 1.02-9.70) and QCOPL-3 (OR 4.19, 95% CI 1.55-11.34). Statistically significant relationships were found in SOA (QCOPL-4: OR 8.16, 95% CI 1.89-35.27; QCOPL-3: OR 5.73, 95% CI 1.36-24.12) and MRI-OA (QCOPL-4: OR 9.54, 95% CI 2.65-34.27; QCOPL-3: OR 9.04, 95% CI 2.65-30.88; QCOPL-2: OR 7.18, 95% CI 2.17-23.70). Occupational activity is associated with knee OA, with dose-response relationships observed in SOA and MRI-OA.

Variaciones en la estimación de la prevalencia de artrosis de rodilla según los criterios diagnósticos utilizados en los estudios poblacionales

Objective To assess the impact of the distinct diagnostic criteria used in population-based studies on estimation of the prevalence of knee osteoarthritis. Methods We performed a search for population-based studies of the prevalence of knee osteoarthritis carried out in the general noninstitutionalized population in Europe or the USA. Results Eight articles were selected, six from Europe and two from the USA. Depending on the study, definition of knee osteoarthritis was based on symptomatic criteria (pain), radiological criteria (the Kellgren and Lawrence scale) or a combination of both symptomatic and radiological criteria. Prevalence estimates ranged from 2.0 to 42.4% with symptomatic criteria, from 16.3 to 33.0% with radiological criteria, and from 1.5 to 15.9% when both criteria were combined. The prevalence was higher for women and increased with age, with the exception of some prevalences estimated through symptoms, which decreased in ages older than 80 years. Conclusions There is a lack of consensus on the criteria used to diagnose knee osteoarthritis in population-based studies of prevalence. Consequently, prevalence estimates vary widely, depending on the diagnostic criteria used, and not only by age and sex. The prevalence was higher when radiological evidence alone was used, followed by symptomatic criteria and by combinations of both.