T1Gd is reduced in bone marrow lesions overlying cartilage in the hip.

OBJECTIVE: Bone Marrow Lesions (BMLs) are areas in bone with high fluid signal on MRI associated with painful and progressive OA. While cartilage near BMLs in the knee has been shown to be degenerated, this relationship has not been investigated in the hip. RESEARCH QUESTION: is T1Gd lower in areas of cartilage overlying BMLs in the hip? DESIGN: 128 participants were recruited from a population-based study of hip pain in 20-49-year-olds. Proton-density weighted fat-suppressed and delayed Gadolinium Enhanced MR Imaging of Cartilage (dGEMRIC) images were acquired to locate BMLs and quantify hip cartilage health. BML and cartilage images were registered and cartilage was separated into BML overlying and surrounding regions. Mean T1Gd was measured in 32 participants with BMLs in both cartilage regions and in matched regions in 32 age- and sex-matched controls. Mean T1Gd in the overlying cartilage was compared using linear mixed-effects models between BML and control groups for acetabular and femoral BMLs, and between cystic and non-cystic BML groups. RESULTS: Mean T1Gd of overlying cartilage was lower in the BML group compared to the control group (acetabular: -105 ms; 95% CI: -175, -35; femoral: -8 ms; 95% CI: -141, 124). Mean T1Gd in overlying cartilage was lower in cystic compared to non-cystic BML subjects, but the confidence interval is too large to provide certainty in this difference (-3 [95% CI: -126, 121]). CONCLUSIONS: T1Gd is reduced in overlying cartilage in hips from a population-based sample of adults aged 20-49, which suggests BMLs are associated with local cartilage degeneration in hips.

Magnetic resonance imaging predictors (cartilage, osteophytes and meniscus) of prevalent and 3-year incident medial and lateral tibiofemoral knee joint tenderness and patellofemoral grind.

OBJECTIVE: To identify magnetic resonance imaging (MRI) predictors (cartilage [C], osteophytes [O] and meniscus [M] scores) of prevalent and 3-year incident medial tibiofemoral (MTF) and lateral tibiofemoral (LTF) knee joint tenderness and patellofemoral (PF) grind.  METHODS: Population-based knee pain cohort aged 40-79 was assessed at baseline (N = 255), 3- and 7-year follow-up (N = 108 × 2 = 216). COM scores were measured at 6/8/6 subregions respectively. Age-sex-BMI adjusted logistic models predicted prevalence versus relevant COM predictors (medial, lateral or patellar / trochlear groove scores). Fully adjusted models also included all relevant COM predictors. Binary generalized estimating equations models predicting 3-year incidence were also adjusted for individual follow-up time between cycles. RESULTS: Significant predictors of prevalent MTF tenderness: medial femoral cartilage (fully adjusted odds ratio [aOR] 1.84; 95% confidence interval [CI] 1.11, 3.05), female (aOR = 3.05; 1.67, 5.58), BMI (aOR = 1.53 per 5 units BMI; 1.10, 2.11). Predictors of prevalent LTF tenderness: female (aOR = 2.18; 1.22, 3.90). There were no predictors of prevalent PF grind in the fully adjusted model. However, medial patellar osteophytes was predictive in the age-sex-BMI adjusted model. There were no predictors of 3-year incident MTF tenderness. Predictors of 3-year incident LTF tenderness: female (aOR = 3.83; 1.25, 11.77). Predictors of 3-year incident PF grind: lateral patellar osteophytes (aOR = 4.82; 1.69, 13.77). In the age-sex-BMI adjusted model, patellar cartilage was also a predictor. CONCLUSION: We explored potential MRI predictors of prevalent and 3-year incident MTF/LTF knee joint tenderness and PF grind. These findings could guide preemptive strategies aimed at reducing these symptoms in the present and future (3-year incidence).

Association between statins and progression of osteoarthritis features on magnetic resonance imaging in a predominantly pre-radiographic cohort: the Vancouver Longitudinal Study of Early Knee Osteoarthritis (VALSEKO): a cohort study.

BACKGROUND: To evaluate the effect of statin use on osteoarthritis (OA) incidence/progression using magnetic resonance imaging (MRI) in a population-based cohort with predominantly pre-radiographic knee OA. METHODS: A cohort aged 40-79 years with knee pain was recruited using random population sampling and followed for 7 years. Baseline exclusions were inflammatory arthritis, recent knee surgery/injury, and inability to undergo MRI. At baseline, current statin use was ascertained. Baseline and follow-up MRIs were read semi-quantitatively for cartilage damage (grade 0-4, 0/1 collapsed, 6 regions), osteophytes (grade 0-3, 8 regions), bone marrow lesions (BML) (grade 0-3, 6 regions) and effusion (grade 0-3). The primary outcome was cartilage damage incidence/progression, while secondary outcomes were incidence/progression of osteophytes, BML, and effusion, each defined as an increase by ≥1 grade at any region. To ensure population representative samples, sample weights were used. Logistic regression was used to assess the association of statin use at baseline with incidence/progression of MRI outcomes. Analyses were adjusted for sex, age, BMI, and multiple comorbidities requiring statin therapy. RESULTS: Of 255 participants evaluated at baseline, 122 completed the 7-year follow-up. Statin use was not significantly associated with progression of cartilage damage (OR 0.82; 95% CI 0.17, 4.06), osteophytes (OR 3.48; 95% CI 0.40, 30.31), BML (OR 0.61; 95% CI 0.12, 3.02), or effusion (OR 2.38; 95% CI 0.42, 13.63), after adjusting for confounders. CONCLUSION: In this population-based cohort of predominantly pre-radiographic knee OA, statins did not affect MRI incidence/progression of cartilage damage, BML, osteophytes or effusion. Therefore, statin use does not appear to affect people with pre-radiographic stages of knee OA.

Reducing the burden of low back pain: results from a new microsimulation model.

BACKGROUND: Low back pain (LBP) causes the highest morbidity burden globally. The purpose of the present study was to project and compare the impact of three strategies for reducing the population health burden of LBP: weight loss, ergonomic interventions, and an exercise program. METHODS: We have developed a microsimulation model of LBP in Canada using a new modeling platform called SimYouLate. The initial population was derived from Cycle 1 (2001) of the Canadian Community Health Survey (CCHS). We modeled an open population 20 years of age and older. Key variables included age, sex, education, body mass index (BMI), type of work, having back problems, pain level in persons with back problems, and exercise participation. The effects of interventions on the risk of LBP were obtained from the CCHS for the effect of BMI, the Global Burden of Disease Study for occupational risks, and a published meta-analysis for the effect of exercise. All interventions lasted from 2021 to 2040. The population health impact of the interventions was calculated as a difference in years lived with disability (YLDs) between the base-case scenario and each intervention scenario, and expressed as YLDs averted per intervention unit or a proportion (%) of total LBP-related YLDs. RESULTS: In the base-case scenario, LBP in 2020 was responsible for 424,900 YLDs in Canada and the amount increased to 460,312 YLDs in 2040. The effects of the interventions were as follows: 27,993 (95% CI 23,373, 32,614) YLDs averted over 20 years per 0.1 unit change in log-transformed BMI (9.5% change in BMI) among individuals who were overweight and those with obesity, 19,416 (16,275, 22,557) YLDs per 1% reduction in the proportion of workers exposed to occupational risks, and 26,058 (22,455, 29,661) YLDs averted per 1% increase in the proportion of eligible patients with back problems participating in an exercise program. CONCLUSIONS: The study provides new data on the relationship between three types of interventions and the resultant reductions in LBP burden in Canada. According to our model, each of the interventions studied could potentially result in a substantial reduction in LBP-related disability.

Association of tramadol with all-cause mortality, cardiovascular diseases, venous thromboembolism, and hip fractures among patients with osteoarthritis: a population-based study.

BACKGROUND: The use of tramadol among osteoarthritis (OA) patients has been increasing rapidly around the world, but population-based studies on its safety profile among OA patients are scarce. We sought to determine if tramadol use in OA patients is associated with increased risks of all-cause mortality, cardiovascular diseases (CVD), venous thromboembolism (VTE), and hip fractures compared with commonly prescribed nonsteroidal anti-inflammatory drugs (NSAIDs) or codeine. METHODS: Using administrative health datasets from British Columbia, Canada, we conducted a sequential propensity score-matched cohort study among all OA patients between 2005 and 2013. The tramadol cohort (i.e., tramadol initiation) was matched with four comparator cohorts (i.e., initiation of naproxen, diclofenac, cyclooxygenase-2 [Cox-2] inhibitors, or codeine). Outcomes are all-cause mortality, first-ever CVD, VTE, and hip fractures within the year after the treatment initiation. Patients were followed until they either experienced an event, left the province, or the 1-year follow-up period ended, whichever occurred first. Cox proportional hazard models were used to estimate hazard ratios after adjusting for competing risk of death. RESULTS: Overall, 100,358 OA patients were included (mean age: 68 years, 63% females). All-cause mortality was higher for tramadol compared to NSAIDs with rate differences (RDs/1000 person-years, 95% CI) ranging from 3.3 (0.0-6.7) to 8.1 (4.9-11.4) and hazard ratios (HRs, 95% CI) ranging from 1.2 (1.0-1.4) to 1.5 (1.3-1.8). For CVD, no differences were observed between tramadol and NSAIDs. Tramadol had a higher risk of VTE compared to diclofenac, with RD/1000 person-years (95% CI) of 2.2 (0.7-3.7) and HR (95% CI) of 1.7 (1.3-2.2). Tramadol also had a higher risk of hip fractures compared to diclofenac and Cox-2 inhibitors with RDs/1000 person-years (95% CI) of 1.9 (0.4-3.4) and 1.7 (0.2-3.3), respectively, and HRs (95% CI) of 1.6 (1.2-2.0) and 1.4 (1.1-1.9), respectively. No differences were observed between tramadol and NSAIDs for all events. CONCLUSIONS: OA patients initiating tramadol have an increased risk of mortality, VTE, and hip fractures within 1 year compared with commonly prescribed NSAIDs, but not with codeine.

Delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage Values in Hips With Bone Marrow Lesions.

OBJECTIVE: Bone marrow lesions (BMLs) are associated with painful and progressive osteoarthritis (OA). Quantitative magnetic resonance imaging (MRI) has been used to study early cartilage degeneration in knees with BML, but similar work has not been done in hips. The purpose of this study was to compare mean delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) relaxation values (T1Gd) in hips with BML to hips without BML in a population-based study. Reduced T1Gd suggests depleted glycosaminoglycan. Our hypothesis was that mean T1Gd is lower in hips with BML compared to hips without BML. METHODS: Study participants (n = 128) were recruited from a cross-sectional population-based study of people ages 20-49 years with and without hip pain. dGEMRIC and proton density (PD)-weighted MRI scans of 1 hip from each participant were used for this analysis. BMLs were identified from PD-weighted fat-suppressed images. We applied a sampling-weighted linear regression model to determine the association of the presence of BMLs with mean cartilage T1Gd (significance: P < 0.05). The model was adjusted for age, sex, body mass index (BMI), hip pain, cam/pincer deformity, and physical activity. RESULTS: Thirty-two (25%) of the 128 participants had at least 1 BML. Subjects with at least 1 BML, compared to those without, had similar weighted characteristics of age, BMI, physical activity levels, and frequency of hip pain. Mean T1Gd was 75.25 msec lower (95% confidence interval -149.69, -0.81; P = 0.048) (9%) in the BML compared to the no-BML group. CONCLUSION: Our results suggest that hips with BMLs are associated with hip cartilage degeneration early in the OA disease process.

Prevalence of joint-specific osteoarthritis and joint pain in British Columbia, Canada.

The objective is to determine the prevalence of self-reported physician-diagnosed osteoarthritis (OA) and musculoskeletal symptoms (pain, stiffness or discomfort) in specific joints among adults in British Columbia (BC), Canada. We carried out a cross-sectional mixed-mode survey in a random population sample of persons 18 years of age and older. Estimates were weighted to reflect the age and sex distribution of the population of BC. We obtained responses from 2,233 individuals. Overall, 18.4% (95% CI 16.8-20.1) of the adult population reported OA. Of those, more than 40% had OA in multiple sites. Prevalence ranged from 8.8% (95% CI 7.6-10.1) in the knee to 2.7% (2.1-3.5) in the foot. One-year prevalence of symptoms ranged from 49.1% (47.0-51.2) in the lower back to 23.3% (21.5-25.1) in the hip. Females reported more symptoms and OA than males in all joints. The most common site of self-reported physician-diagnosed OA in BC is the knee, but OA in the hands, hips, and feet is also common. Having OA in one joint is a strong predictor of OA in other joints.

A comparison of three strategies to reduce the burden of osteoarthritis: A population-based microsimulation study.

OBJECTIVES: The purpose of this study was to compare three strategies for reducing population health burden of osteoarthritis (OA): improved pharmacological treatment of OA-related pain, improved access to joint replacement surgery, and prevention of OA by reducing obesity and overweight. METHODS: We applied a validated computer microsimulation model of OA in Canada. The model simulated a Canadian-representative open population aged 20 years and older. Variables in the model included demographics, body mass index, OA diagnosis, OA treatment, mortality, and health-related quality of life. Model parameters were derived from analyses of national surveys, population-based administrative data, a hospital-based cohort study, and the literature. We compared 8 what-if intervention scenarios in terms of disability-adjusted life years (DALYs) relative to base-case, over a wide range of time horizons. RESULTS: Reductions in DALYs depended on the type of intervention, magnitude of the intervention, and the time horizon. Medical interventions (a targeted increase in the use of painkillers) tended to produce effects quickly and were, therefore, most effective over a short time horizon (a decade). Surgical interventions (increased access to joint replacement) were most effective over a medium time horizon (two decades or longer). Preventive interventions required a substantial change in BMI to generate a significant impact, but produced more reduction in DALYs than treatment strategies over a very long time horizon (several decades). CONCLUSIONS: In this population-based modeling study we assessed the potential impact of three different burden reduction strategies in OA. Data generated by our model may help inform the implementation of strategies to reduce the burden of OA in Canada and elsewhere.

Open MRI assessment of anterior femoroacetabular clearance in active and passive impingement-provoking postures.

AIMS: Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement. METHODS: We recruited nine participants with cam and/or pincer morphologies and with pain, 13 participants with cam and/or pincer morphologies and without pain, and 11 controls from a population-based cohort. We scanned hips in active squatting and passive sitting flexion, adduction, and internal rotation using open MRI and quantified anterior femoroacetabular clearance using the ß angle. RESULTS: In squatting, we found significantly decreased anterior femoroacetabular clearance in painful hips with cam and/or pincer morphologies (mean -11.3° (SD 19.2°)) compared to pain-free hips with cam and/or pincer morphologies (mean 8.5° (SD 14.6°); p = 0.022) and controls (mean 18.6° (SD 8.5°); p < 0.001). In sitting flexion, adduction, and internal rotation, we found significantly decreased anterior clearance in both painful (mean -15.2° (SD 15.3°); p = 0.002) and painfree hips (mean -4.7° (SD 13°); p = 0.010) with cam and/pincer morphologies compared to the controls (mean 7.1° (SD 5.9°)). CONCLUSION: Our results support the anterior femoroacetabular impingement pathomechanism in hips with cam and/or pincer morphologies and highlight the effect of posture on this pathomechanism. Cite this article: Bone Jt Open 2021;2(11):988-996.

Open MRI validation of a hip model driven with subject-specific motion capture data in predicting anterior femoroacetabular clearance.

BACKGROUND: Cam and/or pincer morphologies (CPM) are potential precursors to hip osteoarthritis (OA) and important contributors to non-arthritic hip pain. However, only some CPM hips develop OA and/or pain, and it is not clear why. Anterior impingement between the femoral head/neck contour and acetabular rim during motion is a proposed pathomechanism. Understanding how activity and deformity combine to produce impingement may shed light on the causes of hip degeneration/pain. The objective of this study was to determine the accuracy of a subject-specific hip model driven by subject-specific motion data in predicting anterior impingement. METHODS: We recruited 22 participants with CPM (both with and without pain) and 11 controls. We collected subject-specific 3D kinematics during squatting and sitting flexion, adduction, and internal rotation (FADIR) (an active and a passive maneuver, respectively, proposed to provoke impingement). We then developed 3D subject-specific hip models from supine 3T hip MRI scans that predicted the beta angle (a measure of anterior femoroacetabular clearance) for each frame of acquired kinematics. To assess the accuracy of these predictions, we measured the beta angle directly in the final position of squatting and sitting FADIR using open MRI scans. We selected the frame of motion data matching the static imaged posture using the least-squares error in hip angles. Model accuracy for each subject was calculated as the absolute error between the open MRI measure of beta and the model prediction of beta at the matched time frame. To make the final model accuracy independent of goodness of match between open MRI position and motion data, a threshold was set for least-squares error in hip angles, and only participants that were below this threshold were considered in the final model accuracy calculation, yielding results from 10 participants for squatting and 7 participants for sitting FADIR. RESULTS: For squatting and sitting FADIR, we found an accuracy of 1.1°(0.8°) and 1.3°(mean (SD), and root mean squared error, respectively) and 0.5°(0.3°) and 0.6°, respectively. CONCLUSION: This subject-specific hip model predicts anterior femoroacetabular clearance with an accuracy of about 1°, making it useful to predict anterior impingement during activities measured with motion analysis.

A whole-joint, unidimensional, irreversible, and fine-grained MRI knee osteoarthritis severity score, based on cartilage, osteophytes and meniscus (OA-COM).

OBJECTIVE: To develop a whole-joint, unidimensional, irreversible, and fine-grained MRI knee osteoarthritis (OA) severity score, based on cartilage, osteophytes and meniscus (OA-COM), and to predict progression across different severity states using OA-COM as outcome and clinical variables as predictors. METHODS: Population-based knee pain cohort aged 40-79 was assessed at baseline and 7-year follow-up. OA-COM score was defined as the sum of MRI scores for cartilage, osteophytes and menisci, measured at 6, 8 and 6 sites, total score 0-54. To anchor severity levels, we fit cross-sectional logistic models using OA-COM to predict Kellgren-Lawrence (KL) grades in subsets at or one point below each grade. OA-COM threshold scores were selected on sensitivity, specificity, positive and negative predictive value. We developed longitudinal logistic models for OA-COM progression over each threshold over 7 years. Potential predictors included age, sex, BMI, malalignment, physical exam effusion, quadriceps weakness, and crepitus, selected on area under the receiver operating characteristic curve (AUC) and Akaike's Information Criterion (AIC). RESULTS: Optimal OA-COM thresholds were 12, 18, 24 and 30, for KL grades 1 to 4. Significant predictors of progression (depending on threshold) included physical exam effusion, malalignment and female sex, with other selected predictors age, BMI and crepitus. CONCLUSION: OA-COM (0-54 range) is a whole-joint, unidimensional, irreversible, and fine-grained MRI OA severity score reflecting cartilage, osteophytes and menisci. OA-COM scores 12, 18, 24 and 30 are equivalent to KL grades 1 to 4, while offering fine-grained differentiation of states between KL grades, and within pre-radiographic disease (KL = 0) or late-stage disease (KL = 4). In modeling, several clinical variables predicted progression across different states over 7 years.

Specific manifestations of knee osteoarthritis predict depression and anxiety years in the future: Vancouver Longitudinal Study of Early Knee Osteoarthritis.

BACKGROUND: To evaluate whether knee osteoarthritis (OA) manifestations predict depression and anxiety using cross-sectional and longitudinal prediction models. METHODS: A population-based cohort (n = 122) with knee pain, aged 40-79, was evaluated at baseline, 3 and 7 years. Baseline predictors were: age decade; sex; BMI ≥ 25; physical exam knee effusion; crepitus; malalignment; quadriceps atrophy; flexion; flexion contracture; Kellgren-Lawrence (KL) x-ray grade (0/1/2/3+); WOMAC pain ≥25; WOMAC stiffness ≥25; self-reported knee swelling; and knee OA diagnosis (no/probable/definite). Depression and anxiety, cutoffs 5+ and 7+ respectively, were measured via the Hospital Anxiety and Depression Scale. We fit logistic models at each cycle using multivariable models selected via lowest Akaike's information criterion. RESULTS: Baseline depression model: sex (female OR = 0.27; 0.10, 0.76) and KL grade (KL 1 OR = 4.21; 1.31, 13.48). Three-year depression model: KL grade (KL 1 OR = 18.92; 1.73, 206.25). Seven-year depression model: WOMAC stiffness ≥25 (OR = 3.49; 1.02, 11.94) and flexion contracture ≥1 degree (OR = 0.23; 0.07, 0.81). Baseline anxiety model: knee swelling (OR = 4.11; 1.51, 11.13) and age (50-59 vs. 40-49 OR = 0.31 [0.11, 0.85]; 60-69 OR = 0.07 [0.01, 0.42]). Three-year anxiety model: WOMAC stiffness ≥25 (OR = 5.80; 1.23, 27.29) and KL grade (KL 1 OR = 6.25; 1.04, 37.65). Seven-year anxiety model: sex (female OR = 2.71; 0.87, 8.46). CONCLUSION: Specific knee OA-related manifestations predict depression and anxiety cross-sectionally, 3 years in the future, and for depression, 7 years in the future. This information may prove useful to clinicians in helping to identify patients most at risk of present or future depression and anxiety, thus facilitating preemptive discussions that may help counter that risk.

Biomechanics during cross-body lunging in individuals with and without painful cam and/or pincer morphology.

BACKGROUND: Femoroacetabular impingement is a patho-mechanical hip condition that can lead to restrictions in hip motion, particularly in end-range hip flexion, adduction and/or internal rotation. Radiographic evidence of femoroacetabular impingement - cam and/or pincer morphology - is prevalent in the general and athletic populations. There is, however, a lack of studies that have analyzed the performance of sport-specific movements in people possessing these morphologies. Therefore, the purpose of this study was to compare cross-body lunge biomechanics between individuals with and without painful cam and/or pincer morphology. METHODS: This was an exploratory, cross-sectional study where nine participants with cam and/or pincer morphology and symptoms, thirteen participants with asymptomatic cam and/or pincer morphology, and eleven pain-free controls performed the cross-body lunge during a single session. Trunk, pelvis, hip, knee and ankle kinematics, as well as hip, knee and ankle kinetics and vertical ground reaction forces were examined. FINDINGS: Overall, the groups performed the movement similarly, with most variables statistically similar between groups. However, pelvis sagittal plane excursion throughout the entire cross-body lunge was significantly larger in those with cam and/or pincer morphology and symptoms compared to those with asymptomatic cam and/or pincer morphology (P = .046, effect size = 0.98). INTERPRETATION: The results of this study show that cross-body lunge performance is similar across individuals with and without painful cam and/or pincer morphology. However, future research should aim to better understand pelvis biomechanics during sporting activities, as pelvis sagittal plane excursion may have important implications in rehabilitation and sport performance.

Prevalence of Femoroacetabular Impingement Syndrome among Young and Middle-aged White Adults.

OBJECTIVE: The purpose of the study was to determine the prevalence of femoroacetabular impingement syndrome (FAIS) in white adults 20 to 49 years of age. METHODS: Participants were white men and women aged 20-49 years, recruited through random digit dialing from the population of Metro Vancouver, British Columbia, Canada. Participants filled out a self-administered questionnaire and underwent a physical examination and radiographs of both hips. FAIS was defined as a combination of hip symptoms, physical signs of impingement, and radiological findings of cam or pincer morphology as recommended by the Warwick Agreement. All analyses were weighted to reflect the population from which the sample was drawn. RESULTS: Data were obtained for 500 participants. In the study population, 48.9% were males and the age distribution was 32.2%, 31.4%, and 36.4% in the groups 20-29, 30-39, and 40-49 years, respectively. The physical signs of impingement correlated significantly with symptoms, but there was no significant association between either symptoms or physical examination with radiographic findings. FAIS on either side was found in 3.0% (95% CI 1.5-4.5) of the population. CONCLUSION: In this study, FAIS was present in 3% of whites aged 20-49 years. Further research is needed to develop consistent criteria for assessing hip symptoms, physical signs, and hip joint morphology, and to better understand the relationships between them.

Qualitative study to elicit patients' and primary care physicians' perspectives on the use of a self-management mobile health application for knee osteoarthritis.

OBJECTIVE: To elicit perspectives of family physicians and patients with knee osteoarthritis (KOA) on KOA, its treatment/management and the use of a mobile health application (app) to help patients self-manage their KOA. DESIGN: A qualitative study using Cognitive Task Analysis for physician interviews and peer-to-peer semistructured interviews for patients according to the Patient and Community Engagement Research (PaCER) method. SETTING: Primary care practices and patient researchers at an academic centre in Southern Alberta. PARTICIPANTS: Intentional sampling of family physicians (n=4; 75% women) and patients with KOA who had taken part in previous PaCER studies and had experienced knee pain on most days of the month at any time in the past (n=5; 60% women). RESULTS: Physician and patient views about KOA were starkly contrasting. Patient participants expressed that KOA seriously impacted their lives and lifestyles, and they wanted their knee pain to be considered as important as other health problems. In contrast, physicians uniformly conceptualised KOA as a relatively minor health problem, although they still recognised it as a painful condition that often limits patients' activities. Consequently, physicians did not regard KOA as a condition to be proactively and aggressively managed. The gap between physicians' and patients' conceptualisation of KOA and its treatment extended to the use of an app for self-management. While patients were supportive of the app, physicians were sceptical of its use and focused more on accountability and patient resources. CONCLUSIONS: The clear discord between physicians' mental models and patients' lived experience and perceived needs around KOA emphasised a gap in understanding and communication about treatment and management of KOA. As such, this preliminary and formative research will inform a codesign approach to develop an app that will act as a communications tool between patients and physicians, enabling patient-physician discussions regarding modifiable self-management options based on a patient's perspectives and needs.

Association of Knee Effusion Detected by Physical Examination With Bone Marrow Lesions: Cross-Sectional and Longitudinal Analyses of a Population-Based Cohort.

OBJECTIVE: To determine the association of effusion detected by physical examination with the prevalence of bone marrow lesions (BMLs) on magnetic resonance imaging (MRI), and the incidence/progression of BMLs over 3 years in subjects with knee osteoarthritis. METHODS: A population-based cohort with knee pain (n = 255) was assessed for effusion on physical examination. On MRI, BMLs were graded 0-3 (none, mild, moderate, severe), and incidence/progression was defined as a worsening of the sum of BML scores over 6 surfaces by ≥1 grade. We analyzed the full cohort and a mild disease subsample with a Kellgren/Lawrence (K/L) grade <3. Cross-sectional logistic and longitudinal exponential regression analyses were performed, adjusted for age, sex, body mass index (BMI) and pain. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for effusion detected by physical examination versus BMLs (prevalence and incidence/progression). RESULTS: The weighted mean age was 56.7 years, the mean BMI was 26.5, 56.3% were women, 20.1% had effusion on physical examination, and 80.7% had a K/L grade <3. Effusion on physical examination was significantly associated with prevalent BMLs in the full cohort (odds ratio [OR] 6.10 [95% confidence interval (95% CI) 2.77-13.44]) and in the K/L grade <3 cohort (OR 6.88 [95% CI 2.76-17.15]). In the full cohort, sensitivity, specificity, PPV, and NPV were 34.6, 92.5, 79.9, and 62.1%, respectively, and in the K/L <3 cohort 31.7, 94.0, 75.5, and 70.1%, respectively. Longitudinally, effusion on physical examination was not significantly associated with BML incidence/progression in the full cohort (hazard ratio [HR] 1.83 [95% CI 0.95-3.52]) or in the K/L grade <3 cohort (HR 1.73 [95% CI 0.69-4.33]). In the two cohorts, sensitivity, specificity, PPV, and NPV were 32.0, 82.2, 42.2, and 74.9%, respectively, and 21.2, 85.6, 30.1, and 78.8% respectively. CONCLUSION: BMLs on MRI can be predicted from physical examination effusion cross-sectionally, with a high PPV of 79.9%. Assessment for knee effusion on physical examination is useful for determining potential candidates with BMLs before costly MRI screening for recruitment into clinical trials.

Relationship Between Hip Morphology and Hip-Related Patient-Reported Outcomes in Young and Middle-Aged Individuals: A Population-Based Study.

OBJECTIVE: Radiographic measurements of the alpha angle and the lateral center edge (LCE) angle in the hip joint are important for the diagnosis of femoroacetabular syndrome, a potential risk factor for hip osteoarthritis. Our objective was to determine whether these measurements are associated with hip-related patient-reported outcomes in young and middle-aged individuals. METHODS: A stratified random sample of white men and women ages 20-49 years, with and without hip pain, was selected using random digit dialing from the population of metro Vancouver, Canada. The alpha and LCE angles were measured bilaterally on radiographs using Dunn and anteroposterior views, respectively. Patient-reported outcomes were measured by the Copenhagen Hip And Groin Outcome Score (HAGOS), which has scales for symptoms, pain, daily activities, sports, physical activity, and quality of life (QoL). We performed descriptive analyses and a regression analysis with restricted cubic splines, adjusted for age and sex and weighted for the sampling design. RESULTS: Data were obtained for 500 subjects. The alpha angle distribution was strongly skewed, with a mean of 54°. The LCE angle distribution was symmetric, with a mean of 34°. In the restricted cubic splines analysis, the relationship between the alpha angle and HAGOS scores was nonlinear, with higher alpha angles generally associated with worse HAGOS scores for alpha >60°. The associations were statistically significant for symptoms, sports, and QoL. No association was found between the LCE angle and HAGOS scales. CONCLUSION: In a general population sample ages 20-49 years, we have found an association between the alpha angle and hip-related patient-reported outcomes.

Quadriceps Weakness and Risk of Knee Cartilage Loss Seen on Magnetic Resonance Imaging in a Population-based Cohort with Knee Pain.

OBJECTIVE: To determine whether baseline quadriceps weakness predicts cartilage loss assessed on magnetic resonance imaging (MRI). METHODS: Subjects aged 40-79 with knee pain (n = 163) were recruited from a random population sample and examined for quadriceps weakness with manual isometric strength testing, using a 3-point scoring system (0 = poor resistance, 1 = moderate resistance, 2 = full resistance), which was dichotomized as normal (grade 2) versus weak (grade 0/1). MRI of the more symptomatic knee was obtained at baseline and at mean of 3.3 years. Cartilage was graded 0-4 on MRI. Exponential regression analysis was used to evaluate whether quadriceps weakness was associated with whole knee cartilage loss, and in secondary analyses with compartment-specific cartilage loss, adjusted for age, sex, body mass index, Western Ontario and McMaster Universities Osteoarthritis Arthritis Index pain score, and baseline MRI cartilage score. RESULTS: Of 163 subjects, 54% were female, with a mean age of 57.7 years. Quadriceps weakness was seen in 11.9% of the subjects. Weakness was a predictor of whole knee cartilage loss (HR 3.48, 95% CI 1.30-9.35). Quadriceps weakness was associated with cartilage loss in the medial tibiofemoral (TF) compartment (HR 4.60, 95% CI 1.25-17.02), while no significant association was found with lateral TF (HR 1.53, 95% CI 0.24-9.78) or patellofemoral compartment (HR 2.76, 95% CI 0.46-16.44). CONCLUSION: In this symptomatic, population-based cohort, quadriceps weakness predicted whole knee and medial TF cartilage loss after 3 years. To our knowledge, this is the first study to show that a simple clinical examination of quadriceps strength can predict the risk of knee cartilage loss.

Efficacy of commonly prescribed analgesics in the management of osteoarthritis: a systematic review and meta-analysis.

OBJECTIVE: Pain management is a cornerstone of osteoarthritis (OA) management. The aim of this review is to obtain current, literature-based estimates of the effect of common pharmacologic treatments on pain reduction in OA. METHODS: A MEDLINE search (2006-2016) was conducted for randomized controlled trials studying acetaminophen, oral NSAIDs, topical NSAIDs, COX-2 inhibitors, and opioids in the treatment of OA pain. Drug effect on pain was estimated using relative change in pain, and expressed as percentage change. An overall effect for each drug category was obtained as a weighted average of study-specific effects, with weights based on each study's sample size. RESULTS: Twenty-nine studies were included. The effect on pain was estimated in a total of 43 treatment arms (acetaminophen n = 6, oral NSAIDs n = 9, topical NSAIDs n = 8, COX-2 inhibitors n = 9, and opioids n = 11). Relative (%) changes in pain were found to be as follows: acetaminophen = 32.5, oral NSAIDs = 34.3, topical NSAIDs = 40.9, COX-2 inhibitors = 36.9, and opioids = 35.4. CONCLUSION: The effects of 5 major drug categories in the treatment of OA pain were reviewed with data extracted from 29 studies published from 2006 to 2016. Acetaminophen was found to have an RC value close to that of oral NSAIDs. The effects of oral NSAIDs, COX-2 inhibitors, and opioids in controlling pain were similar to what has been demonstrated in previous literature. Topical NSAIDs were found to have a greater RC than oral NSAIDs.