Walk With Ease (WWE) is an effective low-cost walking program. We estimated the budget impact of implementing WWE in persons with knee osteoarthritis (OA) as a measure of affordability that can ...inform payers’ funding decisions.
We estimated changes in two-year healthcare costs with and without WWE. We used the Osteoarthritis Policy (OAPol) Model to estimate per-person medical expenditures. We estimated total and per-member-per-month (PMPM) costs of funding WWE for a hypothetical insurance plan with 75,000 members under two conditions: 1) all individuals aged 45+ with knee OA eligible for WWE, and 2) inactive and insufficiently active individuals aged 45+ with knee OA eligible. In sensitivity analyses, we varied WWE cost and efficacy and considered productivity costs.
With eligibility unrestricted by activity level, implementing WWE results in an additional $1,002,408 to the insurance plan over two years ($0.56 PMPM). With eligibility restricted to inactive and insufficiently active individuals, funding WWE results in an additional $571,931 over two years ($0.32 PMPM). In sensitivity analyses, when per-person costs of $10 to $1000 were added with 10–50% decreases in failure rate (enhanced sustainability of WWE benefits), two-year budget impact varied from $242,684 to $6,985,674 with unrestricted eligibility and from -$43,194 (cost-saving) to $4,484,122 with restricted eligibility.
Along with the cost-effectiveness of WWE at widely accepted willingness-to-pay thresholds, these results can inform payers in deciding to fund WWE. In the absence of accepted thresholds to define affordability, these results can assist in comparing the affordability of WWE with other behavioral interventions.
Nearly 1 in 60 adolescent athletes will suffer anterior cruciate ligament (ACL) injuries with 90% of these athletes electing to undergo an ACL reconstruction (ACLR) at an estimated annual cost of $3 ...billion. While ACLR and subsequent rehabilitation allow these athletes to return to sports, they have a 15-fold increased risk of second ACL injuries. The modification of post-operative rehabilitation to improve movement and loading symmetry using visual and tactile biofeedback could decrease the risk factors for sustaining a second ACL injury. Participants included 40 adolescent ACLR patients who were intending to return to full sport participation. This preliminary randomized controlled trial (RCT) examined the changes in knee extension moment symmetry, a known risk factor for second ACL injuries, during landing from a stop-jump task between the following time-points: pre-intervention, immediate post-intervention, and subsequent follow-up 6-weeks post-intervention. Participants met twice per week for six-weeks (12-session). The intervention included bilateral squat biofeedback (visual and tactile); the attention control group attended weekly educational sessions. This RCT enrolled and randomize 40 participants over a two-and-a-half-year period. All participants were greater than 4.5 months post-op from a primary, unilateral ACLR and were released to participate by their treating physician. The findings from this pilot biofeedback RCT will provide critical effect size estimates for use in subsequent larger clinical trials.
Osteoarthritis (OA), the leading cause of disability among adults, has no cure and is associated with significant comorbidities. The premise of this randomized clinical trial is that, in a population ...at risk, a 48-month program of dietary weight loss and exercise will result in less incident structural knee OA compared to control.
The Osteoarthritis Prevention Study (TOPS) is a Phase III, assessor-blinded, 48-month, parallel 2 arm, multicenter randomized clinical trial designed to reduce the incidence of structural knee OA. The study objective is to assess the effects of a dietary weight loss, exercise, and weight-loss maintenance program in preventing the development of structural knee OA in females at risk for the disease. TOPS will recruit 1230 ambulatory, community dwelling females with obesity (Body Mass Index (BMI) ≥ 30 kg/m2) and aged ≥50 years with no radiographic (Kellgren-Lawrence grade ≤1) and no magnetic resonance imaging (MRI) evidence of OA in the eligible knee, with no or infrequent knee pain. Incident structural knee OA (defined as tibiofemoral and/or patellofemoral OA on MRI) assessed at 48-months from intervention initiation using the MRI Osteoarthritis Knee Score (MOAKS) is the primary outcome. Secondary outcomes include knee pain, 6-min walk distance, health-related quality of life, knee joint loading during gait, inflammatory biomarkers, and self-efficacy. Cost effectiveness and budgetary impact analyses will determine the value and affordability of this intervention.
This study will assess the efficacy and cost effectiveness of a dietary weight loss, exercise, and weight-loss maintenance program designed to reduce incident knee OA.
ClinicalTrials.gov Identifier: NCT05946044.
Half of the 14 million persons in the US with knee osteoarthritis (OA) are not physically active, despite evidence that physical activity (PA) is associated with improved health. We estimated both ...the quality-adjusted life-year (QALY) losses in the US knee OA population due to physical inactivity and the health benefits associated with higher PA levels.
We used data from the Osteoarthritis Initiative and CDC to estimate the proportions of the US knee OA population aged 45+ that are inactive, insufficiently active, and active and their likelihoods of shifting PA level. We used the Osteoarthritis Policy (OAPol) Model, a computer simulation of knee OA, to determine QALYs lost due to inactivity and to measure potential benefits (comorbidities averted and QALYs saved) of increased PA.
Among 13.7 million persons living with knee OA, 7.5 million total QALYs, or 0.55 QALYs/person, were lost due to inactivity or insufficient PA relative to activity over their remaining lifetimes. Black Hispanic women experienced the highest losses, 0.76 QALYs/person. Females of all races/ethnicities had ~20% higher loss burdens than males. According to our model, if 20% of the inactive population were instead active, 95,920, 222,413, and 214,725 potential cases of cancer, cardiovascular disease, and diabetes would be averted, and 871,541 potential QALYs would be saved.
Physical inactivity leads to substantial QALY losses in the US knee OA population. Increasing activity level in even a fraction of this population may have considerable collateral health benefits, potentially averting cases of cancer, cardiovascular disease, and diabetes. This article is protected by copyright. All rights reserved.
•Study of frontal plane knee joint motion as a treatment moderator of pain-relief.•Frontal plane knee motion is unlikely to predict pain-relief in knee osteoarthritis.•Other patient-specific ...characteristics should be examined to predict pain-relief.
Pain is a cardinal symptom of knee osteoarthritis (OA) and although conservative treatments such as exercise and diet related interventions can reduce pain, effects are modest and can be improved. Frontal plane knee joint motion has been associated with knee pain, and is suggested as a patient-specific characteristic on which to tailor interventions.
Does the association between baseline frontal plane knee joint kinematics and pain-relief differ among overweight and obese people with knee OA who underwent an intervention from the Intensive Diet and Exercise for Arthritis (IDEA) clinical trial: diet-only, exercise-only, and combined diet and exercise intervention?
323 participants with knee OA were included in the analysis (77% females; 66 ± 6 years; 33.5 ± 3.7 kg/m2). At baseline, frontal plane knee joint kinematics during walking were measured using 3-dimensional gait analysis and characterised as peak varus-valgus knee angle, peak varus-valgus excursion, and peak varus angular velocity. Pain was assessed at baseline and 18-month follow-up using the Western Ontario and McMaster Universities Osteoarthritis Index pain subscale. Linear regressions were performed unadjusted and adjusted for covariates to determine if the associations between baseline frontal plane knee joint kinematics and 18-month change in pain differed according to intervention.
The interaction terms between the intervention and measures of frontal plane knee joint kinematics were not statistically significant (all P ≥ 0.05).
We found no evidence to suggest that 18-months of either exercise, diet, or a combination of diet and exercise could be more effective than the other to improve pain based on frontal plane measures of knee kinematics.
PURPOSEUsing three separate models that included total body mass, total lean and total fat mass, and abdominal and thigh fat as independent measures, we determined their association with knee joint ...loads in older overweight and obese adults with knee osteoarthritis (OA).
METHODSFat depots were quantified using computed tomography, and total lean and fat mass were determined with dual energy x-ray absorptiometry in 176 adults (age, 66.3 yr; body mass index, 33.5 kg·m) with radiographic knee OA. Knee moments and joint bone-on-bone forces were calculated using gait analysis and musculoskeletal modeling.
RESULTSHigher total body mass was significantly associated (P ≤ 0.0001) with greater knee compressive and shear forces, compressive and shear impulses (P < 0.0001), patellofemoral forces (P < 0.006), and knee extensor moments (P = 0.003). Regression analysis with total lean and total fat mass as independent variables revealed significant positive associations of total fat mass with knee compressive (P = 0.0001), shear (P < 0.001), and patellofemoral forces (P = 0.01) and knee extension moment (P = 0.008). Gastrocnemius and quadriceps forces were positively associated with total fat mass. Total lean mass was associated with knee compressive force (P = 0.002). A regression model that included total thigh and total abdominal fat found that both were significantly associated with knee compressive and shear forces (P ≤ 0.04). Thigh fat was associated with knee abduction (P = 0.03) and knee extension moment (P = 0.02).
CONCLUSIONSThigh fat, consisting predominately of subcutaneous fat, had similar significant associations with knee joint forces as abdominal fat despite its much smaller volume and could be an important therapeutic target for people with knee OA.
To investigate whether serum concentrations of various inflammatory markers are associated with physical function and disease severity among older obese adults with knee osteoarthritis (OA).
Data are ...from baseline assessments in 274 patients with knee OA participating in an exercise and nutrition intervention study. The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) was used to assess self-reported physical function, pain, and stiffness. The presence of disability was assessed, walking speed was calculated on the basis of the 6-minute walk test, and knee radiographs determined the radiographic severity of OA. Serum concentration of interleukin 6 (IL-6), C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), and the soluble receptors IL-6sR, IL-2sR, TNF-sR1 and TNF-sR2 were measured by ELISA.
In multivariate regression analyses adjusted for age, sex, race, body mass index, comorbid conditions, and use of nonsteroid antiinflammatory drugs, higher serum levels of TNF-sR1 and TNF-sR2 were significantly associated with lower scores on the WOMAC physical function, with more symptoms of pain and stiffness, and with more reported physical disability. In addition, higher serum levels of TNF-sR1 and TNF-sR2 were significantly associated with slower walking speed, and tended to be associated with worse radiographic scores. Higher serum levels of IL-6 tended to be associated with slower walking speed, but no significant associations were observed for CRP, IL-6sR, or IL-2sR.
Especially high levels of the soluble receptors of TNF-alpha were found to be associated with lower physical function, increased OA symptoms, and worse knee radiographic scores in older obese adults with knee OA.
Muscle loss and fat gain contribute to the disability, pain, and morbidity associated with knee osteoarthritis (OA), and thigh muscle weakness is an independent and modifiable risk factor for it. ...However, while all published treatment guidelines recommend muscle strengthening exercise to combat loss of muscle mass and strength in knee OA patients, previous strength training studies either used intensities or loads below recommended levels for healthy adults or were generally short, lasting only 6 to 24 weeks. The efficacy of high-intensity strength training in improving OA symptoms, slowing progression, and affecting the underlying mechanisms has not been examined due to the unsubstantiated belief that it might exacerbate symptoms. We hypothesize that in addition to short-term clinical benefits, combining greater duration with high-intensity strength training will alter thigh composition sufficiently to attain long-term reductions in knee-joint forces, lower pain levels, decrease inflammatory cytokines, and slow OA progression.
This is an assessor-blind, randomized controlled trial. The study population consists of 372 older (age ≥ 55 yrs) ambulatory, community-dwelling persons with: (1) mild-to-moderate medial tibiofemoral OA (Kellgren-Lawrence (KL) = 2 or 3); (2) knee neutral or varus aligned knee ( -2° valgus ≤ angle ≤ 10° varus); (3) 20 kg.m-2 ≥ BMI ≤ 45 kg.m-2; and (3) no participation in a formal strength-training program for more than 30 minutes per week within the past 6 months. Participants are randomized to one of 3 groups: high-intensity strength training (75-90% 1Repetition Maximum (1RM)); low-intensity strength training (30-40%1RM); or healthy living education. The primary clinical aim is to compare the interventions' effects on knee pain, and the primary mechanistic aim is to compare their effects on knee-joint compressive forces during walking, a mechanism that affects the OA disease pathway. Secondary aims will compare the interventions' effects on additional clinical measures of disease severity (e.g., function, mobility); disease progression measured by x-ray; thigh muscle and fat volume, measured by computed tomography (CT); components of thigh muscle function, including hip abductor strength and quadriceps strength, and power; additional measures of knee-joint loading; inflammatory and OA biomarkers; and health-related quality of life.
Test-retest reliability for the thigh CT scan was: total thigh volume, intra-class correlation coefficients (ICC) = 0.99; total fat volume, ICC = 0.99, and total muscle volume, ICC = 0.99. ICC for both isokinetic concentric knee flexion and extension strength was 0.93, and for hip-abductor concentric strength was 0.99. The reliability of our 1RM testing was: leg press, ICC = 0.95; leg curl, ICC = 0.99; and leg extension, ICC = 0.98. Results of this trial will provide critically needed guidance for clinicians in a variety of health professions who prescribe and oversee treatment and prevention of OA-related complications. Given the prevalence and impact of OA and the widespread availability of this intervention, assessing the efficacy of optimal strength training has the potential for immediate and vital clinical impact.
ClinicalTrials.gov, NCT01489462.
Approximately 36 million Americans participate in running each year, with 10.5 million running at least 100 d x yr(-1). Although running injuries are well understood medically, their potential risk ...factors are not. Thus, we presently have limited ability to identify individuals at high risk for overuse injuries.
This study aimed to identify behavioral and physiological risk factors that influenced potential knee injury mechanisms, including knee joint forces and knee moments.
Participants included 20 adults ranging in age from 20 to 55 yr (n = 7 males and n = 13 females). During the first screening visit, quadriceps and hamstring flexibility was assessed, and Q-angle, height, and weight were measured. During the second screening visit, participants completed a series of questionnaires and a gait analysis to calculate knee joint loads. An isokinetic dynamometer was used to measure eccentric and concentric knee extension strength.
Body weight (r = 0.48, P = 0.03), weekly mileage (r = 0.62, P = 0.005), and concentric knee extension strength (r=0.68, P = 0.0001) were significantly correlated with tibiofemoral compressive force. Knee extension moment displayed a negative correlation with hamstring flexibility (r = -0.47, P = 0.04). Both weekly mileage (r = 0.50, P = 0.03) and concentric knee extension strength (r = 0.60, P = 0.01) had significant positive correlations with patellofemoral force.
The results of this study relate larger knee joint loads to poor hamstring flexibility, greater body weight, greater weekly mileage, and greater muscular strength. Most of these risk factors could potentially be modified to reduce joint loads to lower the risk of injury.
Obesity is the most modifiable risk factor, and dietary induced weight loss potentially the best nonpharmacologic intervention to prevent or to slow osteoarthritis (OA) disease progression. We are ...currently conducting a study to test the hypothesis that intensive weight loss will reduce inflammation and joint loads sufficiently to alter disease progression, either with or without exercise. This article describes the intervention, the empirical evidence to support it, and test-retest reliability data.
This is a prospective, single-blind, randomized controlled trial. The study population consists of 450 overweight and obese (BMI = 27-40.5 kg/m2) older (age > or = 55 yrs) adults with tibiofemoral osteoarthritis. Participants are randomized to one of three 18-month interventions: intensive dietary restriction-plus-exercise; exercise-only; or intensive dietary restriction-only. The primary aims are to compare the effects of these interventions on inflammatory biomarkers and knee joint loads. Secondary aims will examine the effects of these interventions on function, pain, and mobility; the dose response to weight loss on disease progression; if inflammatory biomarkers and knee joint loads are mediators of the interventions; and the association between quadriceps strength and disease progression.
Test-retest reliability results indicated that the ICCs for knee joint load variables were excellent, ranging from 0.86 - 0.98. Knee flexion/extension moments were most affected by BMI, with lower reliability with the highest tertile of BMI. The reliability of the semi-quantitative scoring of the knee joint using MRI exceeded previously reported results, ranging from a low of 0.66 for synovitis to a high of 0.99 for bone marrow lesion size.
The IDEA trial has the potential to enhance our understanding of the OA disease process, refine weight loss and exercise recommendations in this prevalent disease, and reduce the burden of disability.
NCT00381290.
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