Objective: To determine the association between changes in semiquantitative magnetic resonance imaging (MRI) biomarkers over 24 months and radiographic and pain progression over 48 months in knees with mild‐to‐moderate osteoarthritis (OA).Methods: We undertook a nested case–control study as part of the Foundation for the National Institutes of Health Biomarkers Consortium Project. We used multivariable logistic regression models to examine the association between change over 24 months in semiquantitative MRI markers and radiographic and pain progression in knee OA. MRIs were read according to the MRI OA Knee Score system. We focused on changes in cartilage, osteophytes, meniscus, bone marrow lesions, Hoffa‐synovitis, and effusion‐synovitis.Results: The most parsimonious model included changes in cartilage thickness and surface area, effusion‐synovitis, Hoffa‐synovitis, and meniscal morphology (C statistic 0.740). Compared with no worsening, worsening in cartilage thickness in ≥3 subregions was associated with 2.8‐fold (95% confidence interval [95% CI] 1.3–5.9) greater odds of being a case, and worsening in cartilage surface area in ≥3 subregions was associated with 2.4‐fold (95% CI 1.3–4.4) greater odds of being a case. Worsening of meniscal morphology in any region was associated with 2.2‐fold (95% CI 1.3–3.8) greater odds of being a case. Worsening effusion‐synovitis and Hoffa‐synovitis were also associated with a greater odds of being a case (odds ratios 2.7 and 2.0, respectively).Conclusion: Twenty‐four–month changes in cartilage thickness, cartilage surface area, effusion‐synovitis, Hoffa‐synovitis, and meniscal morphology were independently associated with OA progression, suggesting that these factors may serve as efficacy biomarkers in clinical trials of disease‐modifying interventions for knee OA.

Background: Anterior cruciate ligament (ACL) injuries are common and potentially disabling and frequently prompt surgical reconstruction. The utilization of ACL reconstruction among ACL-injured patients has not been examined rigorously. Purpose: This study reports the 3-year cumulative incidence of ACL reconstruction among adults with ACL injury and compares demographic and clinical characteristics of ACL-injured patients who do and do not go on to undergo ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: A tertiary health care system patient data repository was used to identify patients diagnosed with an ACL injury between January 1, 2001, and December 31, 2007. Follow-up data were obtained to determine how many patients with ACL injury underwent ACL reconstruction within 3 years of ACL injury diagnosis. Stratified analyses were used to examine incidence rates separately by sex, age, race, primary language, socioeconomic status (SES), and health insurance status. Multivariable logistic regression models were built to examine the association of patient characteristics with utilization of ACL reconstruction. Results: There were 2304 patients, with a mean age of 47 years, diagnosed with an ACL injury between 2001 and 2007. The 3-year cumulative incidence of ACL reconstruction after ACL injury diagnosis was 22.6% (95% CI, 20.9%-24.3%). Eighty-six percent of patients undergoing reconstruction did so within 6 months of injury diagnosis, while 94% underwent reconstruction within 1 year. In multivariable models, several patient features were independently associated with a higher adjusted odds of undergoing ACL reconstruction, including male sex (adjusted odds ratio [aOR], 1.4; 95% CI, 1.1-1.7), younger age (aOR per decade, 1.8; 95% CI, 1.7-2.0), white race (aOR, 1.4; 95% CI, 0.94-1.9), higher SES (aOR, 1.4; 95% CI, 1.04-1.8 for high vs low SES; aOR, 1.3; 95% CI, 1.02-1.8 for medium vs low SES), and private health insurance versus self-pay (aOR, 1.9; 95% CI, 1.04-3.5). Conclusion: Less than a quarter of patients with a diagnosed ACL injury underwent ACL reconstruction in the 3 years after diagnosis. The odds of having surgery were higher for men, whites, younger patients, patients with higher SES, and patients with private health insurance.

Background: While obesity may be a risk factor for complications following total knee arthroplasty, data remain sparse on the impact of the degree of obesity on patient-reported outcomes following this procedure. Our objective was to determine the extent to which obesity level affects the trajectory of recovery as well as patient-reported pain, function, and satisfaction with surgery following total knee arthroplasty. Methods: We followed a cohort of patients who underwent total knee arthroplasty at 1 of 4 medical centers. Patients were ≥40 years of age with a primary diagnosis of osteoarthritis. We stratified patients into 5 groups according to the World Health Organization classification of body mass index (BMI). We assessed the association between BMI group and pain and function over the time intervals of 0 to 3, 3 to 6, and 6 to 24 months using a piecewise linear model. We also assessed the association between BMI group and patient-reported outcomes at 24 months. Multivariable models adjusted for age, sex, race, diabetes, musculoskeletal functional limitations index, pain medication use, and study site. Results: Of the 633 participants included in our analysis, 19% were normal weight (BMI of <25 kg/m²), 32% were overweight (BMI of 25 to 29.9 kg/m²), 27% were class-I obese (BMI of 30 to 34.9 kg/m²), 12% were class-II obese (BMI of 35 to 39.9 kg/m²), and 9% were class-III obese (BMI of ≥40 kg/m²). Study participants with a higher BMI had worse preoperative WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) pain and function scores and had greater improvement from baseline to 3 months. The mean change in pain and function from 3 to 6 and from 6 to 24 months was similar across all BMI groups. At 24 months, participants in all BMI groups had similar levels of pain, function, and satisfaction. Conclusions: Because of the differential trajectory of recovery in the first 3 months following total knee arthroplasty, the participants in the higher BMI groups were able to attain absolute pain and function scores similar to those in the nonobese and class-I obese groups. These data can help surgeons discuss expectations of pain relief and functional improvement with total knee arthroplasty candidates with higher BMI. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.