Incidence Of Knee Osteoarthritis Research Articles

Risk of Knee Osteoarthritis With Obesity, Sarcopenic Obesity, and Sarcopenia.

Obesity, defined by anthropometric measures, is a well-known risk factor for knee osteoarthritis (OA), but there is a relative paucity of data regarding the association of body composition (fat and muscle mass) with risk of knee OA. We undertook this study to examine the longitudinal association of body composition categories based on fat and muscle mass with risk of incident knee OA. We included participants from the Multicenter Osteoarthritis Study, a longitudinal cohort of individuals with or at risk of knee OA. Based on body composition (i.e., fat and muscle mass) from whole-body dual x-ray absorptiometry, subjects were categorized as obese nonsarcopenic (obese), sarcopenic obese, sarcopenic nonobese (sarcopenic), or nonsarcopenic nonobese (the referent category). We examined the relationship of baseline body composition categories with the risk of incident radiographic OA at 60 months using binomial regression with robust variance estimation, adjusting for potential confounders. Among 1,653 subjects without radiographic knee OA at baseline, significantly increased risk of incident radiographic knee OA was found among obese women (relative risk [RR] 2.29 [95% confidence interval {95% CI} 1.64-3.20]), obese men (RR 1.73 [95% CI 1.08-2.78]), and sarcopenic obese women (RR 2.09 [95% CI 1.17-3.73]), but not among sarcopenic obese men (RR 1.74 [95% CI 0.68-4.46]). Sarcopenia was not associated with risk of knee OA (for women, RR 0.96 [95% CI 0.62-1.49]; for men, RR 0.66 [95% CI 0.34-1.30]). In this large longitudinal cohort, we found body composition-based obesity and sarcopenic obesity, but not sarcopenia, to be associated with risk of knee OA. Weight loss strategies for knee OA should focus on obesity and sarcopenic obesity.

Body Mass Index Mediates the Association between Dietary Fiber and Symptomatic Knee Osteoarthritis in the Osteoarthritis Initiative and the Framingham Osteoarthritis Study

Dietary fiber reduces body weight and inflammation in clinical trials. It is unclear whether body mass index (BMI) and inflammation might explain the observed association between higher fiber intake and the lower risk of symptomatic knee osteoarthritis (SXKOA). We quantified the extent to which BMI and inflammation influenced the relation between dietary fiber and SXKOA. We used longitudinal data from the Osteoarthritis Initiative (OAI) and the Framingham Offspring Osteoarthritis Study. At baseline of each study, men and women (mean age: 61 y) with or at risk of knee osteoarthritis were followed for 48 mo in the OAI. Adults (mean age: 53 y) were followed for 9.5 y in the Framingham study. Dietary fiber intake was estimated using a validated food-frequency questionnaire. Measured weight and height were used to calculate BMI. Serum high-sensitivity C-reactive protein (CRP) was measured in the Framingham study only. Incident SXKOA was defined as new onset of a combination of knee pain and radiographic osteoarthritis. We applied marginal structural models to quantify the mediation through BMI in the OAI and the sequential mediation through BMI and CRP in the Framingham study. Incident SXKOA occurred in 861 knees among 2876 persons in the OAI and in 143 knees among 971 persons in the Framingham study. In persons whose fiber intake was ≥21 g/d compared with those with intakes <21 g/d, the OR (95% CI) was 0.70 (0.53, 0.91) for the overall association with SXKOA and was 0.93 (0.92, 0.95) for the mediation via BMI (per kg/m2) in the OAI. In the Framingham study, the overall association was 0.57 (0.30, 1.09), the mediation through BMI (via BMI and the influence of BMI on CRP) was 0.94 (0.85, 1.02), and the mediation through CRP (per milligram per liter) was 0.99 (0.84, 1.19). Our findings suggest that the inverse association of fiber intake and the risk of incident symptomatic knee osteoarthritis is partially mediated by BMI.

Consumption of dairy products in relation to the presence of clinical knee osteoarthritis: The Maastricht Study

PurposeObservational studies showed inverse associations between milk consumption and knee osteoarthritis (knee OA). There is lack of information on the role of specific dairy product categories. We explored the association between dairy consumption and the presence of knee osteoarthritis in 3010 individuals aged 40–75 years participating in The Maastricht Study.MethodsThe presence of knee OA was defined according to a slightly modified version of the American College of Rheumatology (ACR) clinical classification criteria. Data on dairy consumption were appraised by a 253-item FFQ covering 47 dairy products with categorization on fat content, fermentation or dairy type. Multivariable logistic regression analyses were performed to estimate odd ratios (ORs) and 95% confidence intervals (95%CI), while correcting for relevant factors.Results427 (14%) participants were classified as having knee OA. Significant inverse associations were observed between the presence of knee OA and intake of full-fat dairy and Dutch, primarily semi-hard, cheese, with OR for the highest compared to the lowest tertile of intake of 0.68 (95%CI 0.50–0.92) for full-fat dairy, and 0.75 (95%CI 0.56–0.99) for Dutch cheese. No significant associations were found for other dairy product categories.ConclusionIn this Dutch population, higher intake of full-fat dairy and Dutch cheese, but not milk, was cross-sectionally associated with the lower presence of knee OA. Prospective studies need to assess the relationship between dairy consumption, and in particular semi-hard cheeses, with incident knee OA.

Bone shape mediates the relationship between sex and incident knee osteoarthritis

BackgroundKnee bone shape differs between men and women and the incidence of knee osteoarthritis (OA) is higher in women than in men. Therefore, the purpose of the present study was to determine whether the observed difference in the incidence of knee radiographic OA (ROA) between men and women is mediated by bone shape.MethodsWe randomly sampled 304 knees from the OAI with incident ROA (i.e., development of Kellgren/Lawrence grade ≥ 2 by month 48) and 304 knees without incident ROA. We characterized distal femur and proximal tibia shape on baseline radiographs using Statistical Shape Modeling. If a specific bone shape was associated with the risk of incident ROA, marginal structural models were generated to assess the mediation effect of that bone shape on the relation of sex and risk of incident knee ROA adjusting for baseline covariates.ResultsCase and control participants were similar by age, sex and race, but case knees were from higher body mass index (BMI) participants (29.4 vs. 27.0; p < 0.001). Women had 49% increased odds of incident knee ROA compared with men (adjusted odds ratio (OR) = 1.49, 95% Confidence Interval (C.I.): 1.04, 2.12). There was an inconsistent mediation effect for tibial mode 2 between sex and incident knee ROA, with an indirect effect OR of 0.96 (95% C.I.: 0.91–1.00) and a direct effect OR of 1.56 (95% C.I.: 1.08–2.27), suggesting a protective effect for this mode. Similar findings were also observed for the mediation effect of tibia mode 10 and femur mode 4. These shape modes primarily involved differences in the angular relation of the heads to the shafts of the femur and tibia.ConclusionsDistal femur and proximal tibia bone shapes partially and inconsistently mediated the relationship between sex and incident knee OA. Women had a higher risk of incident ROA, and specific bone shapes modestly protected them from even higher risk of ROA. The clinical significance of these findings warrant further investigation.

Acoustic emission technique as an adaptive biomarker in integrity analysis of knee joint

Acoustic emission (AE) technique has been applied as an adaptive biomarker for evaluating the disorder of knee joint. Integrity analysis of knee joint involves a detail study of several anatomical parts of knee joint like bones, cartilage, tendons etc. Any damage of these anatomical parts causes several knee diseases like osteoarthritis (OA). The incidence of knee OA, a widely manifested knee disease, particularly in aging society, increases due to some damages in the cartilage of knee joint. The major concern of this disease (OA) is its incurability at its matured stage. However, early detection for adopting appropriate measures can reduce the risk of this disease [1], [2]. The present investigation focuses on the dynamical behavioral characterization of knee joint for its integrity analysis with acoustic emission (AE) characterizing parametric features. AE signals have been collected from different positions of tibia, patella, femur etc. by AE sensors with adaptive frequency bands for getting sufficient information about the condition of cartilage in knee joint. Data has been collected from the participants with different age groups without any knee problems as well as participants with knee diseases. All data have been clarified effectively to identify the proposed technique as an adaptive biomarker for monitoring knee condition in early stage of OA effectively.

Risk Factor for Knee Osteoarthritis Among Women

Background and Aim: Osteoarthritis is now firmly establish as public health problem. It is the most disabling diseases in many countries. Knee osteoarthritis is regarded as the most common form of the disease in adults. Elderly women are more affect by this disorder. From the available evidences, it is now reasonable to consider this disease as one of the most important among the chronic diseases and investigation for the risk factors that are associated with this disorder is very important. Aim of study to assess risk factors of osteoarthritis of the knee joint among women. Material and method: Case control study, where 200 women with symptomatic knee osteoarthritis proved by physical examinations and radiological evidences were allocate as cases. In addition, 200 women proved to be without clinical or radiological evidence of knee osteoarthritis were allocate as controls. The study was applied from 15th November 2013 to 7th april 2014. Questionnaire which focus on the distribution of the study population according to personal characteristics such as (Family history, smoking, sedentary lifestyle, walk long, employment and urban), life events as (previous trauma, stress previous surgery),other variables such as (BMI, DM, HT, genitourinary, calcium intake). Results: Smoking appeared in this study to be highly associated with knee osteoarthritis at (p-value =0.007), Sedentary lifestyle associated with development of knee Osteoarthritis (P-value =0.000).Unhealthy calcium intake was highly associated with development of knee osteoarthritis(P-Value=0.000),Walking for long distances appeared unexpected negatively associated with occurrence of knee Osteoarthritis(P-value=0.84). Employment appears unexpected negative associated with occurrence of knee Osteoarthritis (p-value= 0.129). Conclusion: Obese Women, diabetes mellitus, genitourinary infection, stress and previous surgery are the high risk for developing knee osteoarthritis, while hypertensive women or women with previous trauma has low risks for developing knee osteoarthritis. Recommendation: the study recommended avoiding sitting for long times, apply exercise regularly and encourage calcium intake for women to decrease the incidence of knee osteoarthritis. Keyword: Risk factor, Knee ,Osteoarthritis ,Women

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

Comparative study of total knee replacement Vs non surgical treatment regarding management of knee osteoarthritis

Osteoarthritis (OA) is a type of joint disease that results from breakdown of joint cartilage and underlying bone. The most common symptoms are joint pain and stiffness. Osteoarthritis (OA) is a common disease of aged population and one of the leading causes of disability. Incidence of knee OA is rising by increasing average age of general population. Age, weight, trauma to joint due to repetiting movements in particular squatting and kneeling are common risk factors of knee OA. Several factors including cytokines, leptin, and mechanical forces are pathogenic factors of knee OA. Treatment options for osteoarthritis typically depend on the severity of the condition and the particular joints involved. They most often include medication Physical activity, stretching, and weight management, physical and occupational therapy, with or without assistive devices and surgery. The most common surgeries to treat knee arthritis are total knee replacement (total knee arthroplasty), partial knee replacement (unicompartmental knee arthroplasty), knee osteotomy (tibial osteotomy or femoral osteotomy), knee arthroscopy and cartilage repair and restoration. In this randomized, controlled trial, we enrolled 90 patients with moderate-to severe knee osteoarthritis who were eligible for unilateral total knee replacement. Patients were randomly assigned to undergo total knee replacement followed by 10 weeks of nonsurgical treatment (total-knee-replacement group) or to receive only the 10 weeks of nonsurgical treatment (nonsurgical-treatment group), which was delivered by physiotherapists and dietitians and consisted of exercise, education, dietary advice, use of insoles, and pain medication. The primary outcome was the change from baseline to 10 months in the mean score on four Knee Injury and Osteoarthritis Outcome Score subscales, covering pain, symptoms, activities of daily living, and quality of life (KOOS4); scores range from 0 (worst) to 100 (best). A total of 80 patients completed the 10-month follow-up assessment. In the nonsurgical-treatment group, 11 patients underwent total knee replacement before the 10-month follow-up; in the total-knee-replacement group, 1 patient received only nonsurgical treatment. In the intention-to-treat analysis, the total-kneereplacement group had greater improvement in the KOOS4 score than did the nonsurgical- treatment group. The total-knee-replacement group had a higher number of serious adverse events than did the nonsurgical-treatment group. In patients with knee osteoarthritis who were eligible for unilateral total knee replacement, treatment with total knee replacement followed by nonsurgical treatment resulted in greater pain relief and functional improvement after 10 months than did nonsurgical treatment alone. However, total knee replacement was associated with a higher number of serious adverse events than was nonsurgical treatment, and most patients who were assigned to receive nonsurgical treatment alone did not undergo total knee replacement before the 10-month follow-up.

Is local or central adiposity more strongly associated with incident knee osteoarthritis than the body mass index in men or women?

To determine whether central (abdominal) or peripheral (thigh) adiposity measures are associated with incident radiographic knee osteoarthritis (RKOA) independent of body mass index (BMI) and whether their relation to RKOA was stronger than that of BMI. 161 Osteoarthritis Initiative (OAI) participants (62% female) with incident RKOA (Kellgren/Lawrence grade 0/1at baseline, developing an osteophyte and joint space narrowing (JSN) grade ≥1 by year-4) were matched to 186 controls (58% female) without incident RKOA. Baseline waist-height-ratio (WHtR), and anatomical cross-sectional areas of thigh subcutaneous (SCF) and intermuscular fat (IMF) were measured, the latter using axial magnetic resonance images. Logistic regression assessed the relationship between each adiposity measure and incident RKOA before and after adjustment for BMI, and area under receiver operating characteristic curves (AUC) for each adiposity measure was compared to that of BMI using chi-squared tests. BMI, WHtR, subcutaneous fat (SCF) and IMF were all significantly associated with incident RKOA when analysed separately, with similar effect sizes (odds ratio range 1.30-1.53). After adjusting for BMI, odds ratios (ORs) for WHtR, SCF and IMF were attenuated and no longer statistically significant. No measure of central or peripheral adiposity was significantly more strongly associated with incident RKOA than BMI. Results were similar for men and women. Although both central (WHtR) and peripheral (SCF and IMF) adiposity were significantly associated with incident RKOA, neither was more strongly associated with incident RKOA than BMI. The simple measure of BMI appears sufficient to capture the elevated risk of RKOA associated with greater amounts of localised adiposity.

Characterizing the distinct structural changes associated with self-reported knee injury among individuals with incident knee osteoarthritis: data from the osteoarthritis initiative

We aimed to characterize the agreement between distinct structural changes on magnetic resonance (MR) imaging and self-reported injury in the 12 months leading to incident common or accelerated knee osteoarthritis (KOA). We conducted a descriptive study using data from baseline and the first 4 annual visits of the Osteoarthritis Initiative. Knees had no radiographic KOA at baseline (Kellgren-Lawrence [KL]<2). We classified two groups: (1) accelerated KOA: a knee developed advanced-stage KOA (KL = 3 or 4) within 48 months and (2) common KOA: a knee increased in radiographic severity (excluding those with accelerated KOA). Adults were 1:1 matched based on sex. The index visit was when a person met the accelerated or common KOA criteria. We limited our sample to people with MR images and self-reported injury data at index visit and year prior. Among 226 people, we found fair agreement between self-reported injuries and distinct structural changes (kappa = 0.24 to 0.31). Most distinct structural changes were medial meniscal pathology. No distinct structural changes (e.g., root or radial tears) appeared to differ between adults who reported or did not report an injury; except, all subchondral fractures occurred in adults who developed accelerated KOA and reported an injury. While there is fair agreement between self-reported knee injuries and distinct structural changes, there is some discordance. Self-reported injury may represent a different construct from distinct structural changes that occur after joint trauma. Clin. Anat. 31:330-334, 2018. © 2018 Wiley Periodicals, Inc.

Predictive value of early osteoarthritic/degenerative changes on radiography and MRI for incident clinical and radiographic knee OA in overweight and obese women

Predictive value of early osteoarthritic/degenerative changes on radiography and MRI for incident clinical and radiographic knee OA in overweight and obese women

Body fat distribution and its association with risk of incident radiographic knee osteoarthritis

Body fat distribution and its association with risk of incident radiographic knee osteoarthritis

Predictive value of early structural changes on radiographs and MRI for incident clinical and radiographic knee osteoarthritis in overweight and obese women.

To determine the predictive value of tibiofemoral (TF), patellofemoral (PF) MRI osteoarthritis (OA), and Kellgren and Lawrence grade 1 (KLG1) for the incidence of knee OA (clinical and/or radiological signs) at 2.5 and 6.5 years follow-up in a high-risk cohort. Data of the PROOF study were used, consisting of middle-aged obese women without clinical (ACR-criteria) knee OA and free of radiographic signs (KLG < 2) at baseline. To determine the relation between MRI defined knee OA and KLG1 at baseline with clinical (ACR criteria) or radiographic OA (KLG ≥ 2) at the follow-up points, sensitivity, specificity, likelihood ratios and pre-test and post-test probabilities were calculated. The baseline prevalence of KLG1 (42.9%) was higher than TF MRI OA (14.6%) and PF MRI OA (10.0%). All diagnostic performance statistics indicated better prediction for radiographic OA than for clinical OA. For both outcomes and time points, the absolute difference between pre-test and post-test probabilities was the highest for TF MRI OA. The number needed to screen to obtain a certain number of cases with definite knee OA after a given follow-up period was higher (16-524%) for MRI OA, than for KLG1. When comparing the associations and post-test probabilities, TF MRI OA was more strongly related to the development of radiographic knee OA than KLG1. However, for the selection of people at high risk for developing knee OA, for instance for preventive trials, radiography seems to be sufficient, due to the high baseline prevalence.

Risk factors for progression of radiographic knee osteoarthritis in elderly community residents in Korea

BackgroundKnee osteoarthritis (OA) is the most common form of arthritis affecting the elderly. Understanding the risk factors for knee OA has been derived from cross sectional studies. There have been few longitudinal studies of risk factors for knee OA among Asian populations. The purpose of this study was to evaluate the risk factors for knee OA in elderly Korean community residents.MethodsThis prospective, population-based study was conducted on residents over 50 years of age in Chuncheon who participated in the Hallym Aging Study. Standardized weight-bearing semi-flexed knee anteroposterior radiographs were obtained in 2007 and in 2010. Of 504 participants at baseline, 322 participants (male: female = 150:172) underwent follow-up knee radiographs. Radiographic knee OA was defined as Kellgren/Lawrence (K-L) grade of ≥ 2. Risk factors assessed at baseline were tested for their association with incidence, progression, and worsening of radiographic knee OA by logistic regression analysis.ResultsThe median age of these participants at follow-up was 71 years (interquartile range 66–75 years). Incident OA was observed in 33 (10.2%) and progression of OA (defined as an increase of Kellgren-Lawrence (K-L) grade at follow-up, from grades 2 or 3 at baseline) in 43 (13.55%) participants. In multivariate logistic regression analysis, only females were significantly associated with the progression of radiographic knee OA (odds ratio [OR] = 4.41, 95% confidence interval [CI] 1.32–14.77).ConclusionsIn this 3-year longitudinal study, the yearly incidence and progression of knee OA was higher than those previously reported in Western populations.

Characterizing the distinct structural changes associated with self-reported knee injury among individuals with incident knee osteoarthritis: Data from the osteoarthritis initiative.

We aimed to characterize the agreement between distinct structural changes on magnetic resonance (MR) imaging and self-reported injury in the 12 months leading to incident common or accelerated knee osteoarthritis (KOA). We conducted a descriptive study using data from baseline and the first 4 annual visits of the Osteoarthritis Initiative. Knees had no radiographic KOA at baseline (Kellgren-Lawrence [KL]<2). We classified two groups: (1) accelerated KOA: a knee developed advanced-stage KOA (KL = 3 or 4) within 48 months and (2) common KOA: a knee increased in radiographic severity (excluding those with accelerated KOA). Adults were 1:1 matched based on sex. The index visit was when a person met the accelerated or common KOA criteria. We limited our sample to people with MR images and self-reported injury data at index visit and year prior. Among 226 people, we found fair agreement between self-reported injuries and distinct structural changes (kappa = 0.24 to 0.31). Most distinct structural changes were medial meniscal pathology. No distinct structural changes (e.g., root or radial tears) appeared to differ between adults who reported or did not report an injury; except, all subchondral fractures occurred in adults who developed accelerated KOA and reported an injury. While there is fair agreement between self-reported knee injuries and distinct structural changes, there is some discordance. Self-reported injury may represent a different construct from distinct structural changes that occur after joint trauma. Clin. Anat. 31:330-334, 2018. © 2018 Wiley Periodicals, Inc.

Objectively Measured Physical Activity and Risk of Knee Osteoarthritis

This study aimed to examine the association between objectively measured physical activity and risk of developing incident knee osteoarthritis (OA) in a community-based cohort of middle-age and older adults. We used data from the Osteoarthritis Initiative, an ongoing prospective cohort study of adults 45 to 83 yr of age at initial enrollment with elevated risk of symptomatic knee OA. Moderate-vigorous physical activity (MVPA) was measured by a uniaxial accelerometer for seven continuous days in two data collection cycles and was categorized as inactive (<10 min·wk), low activity (10-<150 min·wk), and active (≥150 min·wk). Incident knee OA based on radiographic and symptomatic OA and joint space narrowing were analyzed as outcomes over 4 yr of follow-up. Participants free of the outcome of interest in both knees at study baseline were included (sample sizes ranged from 694 to 1331 for different outcomes). We estimated hazard ratio (HR) with 95% confidence intervals (CI). In multivariate analyses, active MVPA participation was not significantly associated with risk of incident radiographic knee OA (HR = 1.52, 95% CI = 0.68-3.40), symptomatic knee OA (HR = 1.17, 95% CI = 0.44-3.09), or joint space narrowing (HR = 0.87, 95% CI = 0.37-2.06) when compared with inactive MVPA participation. Similar results were found for participants with low activity MVPA. MVPA was not associated with the risk of developing incident knee OA or joint space narrowing over 4 yr of follow-up among Osteoarthritis Initiative participants who are at increased risk of knee OA.

Meta-analysis of serum C-reactive protein and cartilage oligomeric matrix protein levels as biomarkers for clinical knee osteoarthritis

BackgroundThe roles of C-reactive protein (CRP) and cartilage oligomeric matrix protein (COMP) in knee osteoarthritis (KOA) remain controversial, thus the present study is aimed to explore the relationships between CRP, COMP, and the incidence/progression of KOA.MethodsA systematic search was conducted on PubMed and Embase until September, 2016 for all the relevant studies. The pooled mean difference (MD) with its 95% confidence interval (95% CI) based on fixed effects model or random effects model was calculated to assess the potential role of CRP and COMP in the incidence or progression of KOA. Heterogeneity was evaluated by Cochran’s Q and I2 tests. When P < 0.05 or I2 > 50%, a random effects model was chosen, otherwise, a fixed effects model was used. Moreover, the role of CRP in different degrees of pain was also analyzed. Sensitivity analysis was performed to evaluate the strength of the meta-analysis.ResultsFourteen studies were enrolled in the meta-analysis. No difference was found between baseline CRP and CRP levels in the last follow-up period of KOA (MD = − 0.09, 95% CI: -0.30, 0.13). Pooled data showed higher CRP concentration in patients with incident KOA when compared with controls (MD = 0.33, 95% CI: 0.04, 0.63). Moreover, higher serum COMP levels were found in patients with incident KOA (MD = 1.69, 95% CI: 0.61, 2.76) Additionally, significant higher CRP concentration was observed in KOA patients with highest degree of pain (MD = 1.60, 95% CI: 0.52, 2.67).ConclusionCRP and COMP serum levels were both associated with the incidence of KOA. Patients with a higher CRP and COMP concentration might have an increased probability of developing KOA. However, higher CRP serum levels was not related with KOA progression. Furthermore, KOA patients with more pain had higher CRP concentrations.

Effect of obesity on self-reported pain and functional disability in patients with knee osteoarthritis in Zaria, North Western Nigeria

Introduction: Osteoarthritis (OA) is the most common causes of arthritis in human, with the knee joint being the most commonly affected. Knee OA patients often present with knee pain and varying degree of functional limitation in activities of daily living. The incidence and prevalence of knee OA increases with age and is poised to increase even further in tandem with an expected increase in life expectancy, rise in population age, and increased prevalence of obesity. Obesity is associated with the occurrence and severity of knee OA, and it is perhaps the most amenable of all knee OA risk factors. The contribution of obesity to pain and functional limitation in Nigerian knee OA patients is not well elucidated. This study aims at ascertaining the burden of obesity in Nigerian knee OA patients with regards to its prevalence, effects on pain, and functional disability. Materials and Methods: Between January 2010 and February 2011, 140 consenting knee OA patients were recruited consecutively, as they presented to the Rheumatology Clinic of Ahmadu Bello University Teaching Hospital, Zaria. Knee OA was diagnosed in patients using American College of Rheumatology clinicoradiographic criteria. Information was collected from patient using a pretested interviewer-administered structured question. Pain, stiffness, and functional disability were determined using Likert version of Western Ontario McMaster Universities Osteoarthritis index (WOMAC). Patients were grouped based on body mass index (BMI) into obese (BMI > 30 kg/m2) and nonobese (BMI

Neuromuscular adaptations in older males and females with knee osteoarthritis during weight-bearing force control

BackgroundFemales exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA. ObjectiveTo identify sex-related differences in OA-affected adults and within-sex differences between healthy and OA-affected adults' muscular activation patterns during lower limb loading. MethodsThirty adults with OA and 36 controls completed a standing ground reaction force (GRF) matching protocol requiring participants to expose equal body weight to each leg and modulate horizontal GRFs while maintaining constant joint positions. Electromyography was plotted as a function of GRF direction to depict muscle activation patterns. Muscles were classified as a general joint stabilizer, specific joint stabilizer or moment actuator by quantifying activation patterns with a test of asymmetry, specificity index and mean direction of activity. Lower limb kinematics and kinetics were also recorded. ResultsIn general, muscle roles as it relates to joint stability did not differ between groups. Compared to controls, both males and females with OA demonstrated greater rectus femoris activity and reduced knee rotation moments. Females with OA had significantly greater biceps femoris and gastrocnemius activity during respective lateral, and anterior–medial loading directions compared to males with OA. ConclusionsWe identified fundamental differences in muscular stabilization strategies in older adults with OA as well as sex-related changes in neuromuscular function that may influence joint loading conditions and provide insight into the greater incidence of knee OA in females.

Bone Mineral Density and the Risk of Hip and Knee Osteoarthritis: The Johnston County Osteoarthritis Project.

To address knowledge gaps regarding the relationship between bone mineral density (BMD) and incident hip or knee osteoarthritis (OA); specifically, lack of information regarding hip OA or symptomatic outcomes. Using data (n = 1,474) from the Johnston County Osteoarthritis Project's first (1999-2004) and second (2005-2010) followup of participants ages ≥45 years, we examined the association between total hip BMD and both hip and knee OA. Total hip BMD was measured using dual x-ray absorptiometry, and participants were classified into sex-specific quartiles (low, intermediate low, intermediate high, and high). Radiographic OA (ROA) was defined as development of Kellgren/Lawrence grade ≥2. Symptomatic ROA (sROA) was defined as onset of both ROA and symptoms. Weibull regression modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs). Median followup time was 6.5 years (range 4.0-10.2 years). In multivariate models, and compared with participants with low BMD, those with intermediate high and high BMD were less likely to develop hip sROA (HR 0.52 [95% CI 0.31-0.86] and 0.56 [95% CI 0.31-0.86], respectively; P = 0.024 for trend); high BMD was not associated (HR 0.69 [95% CI 0.45-1.06]) with risk of hip ROA. Compared with participants with low BMD, those with intermediate low and intermediate high total hip BMD were more likely to develop knee sROA (HR 2.15 [95% CI 1.40-3.30] and 1.65 [95% CI 1.02-2.67], respectively; P = 0.325 for trend); similar associations were seen with knee ROA. Our findings suggest that higher BMD may reduce the risk of hip sROA, while intermediate levels may increase the risk of both knee sROA and ROA.