Effect of Obesity on Pain and Functional Recovery Following Total Knee Arthroplasty

Abstract

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/m 2), 32% were overweight (BMI of 25 to 29.9 kg/m 2), 27% were class-I obese (BMI of 30 to 34.9 kg/m 2), 12% were class-II obese (BMI of 35 to 39.9 kg/m 2), and 9% were class-III obese (BMI of ‡40 kg/m 2). 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. K nee osteoarthritis is a prevalent, disabling joint disease that affects almost 4% of the global population 1,2. Knee osteoarthritis is more prevalent in obese individuals, and increased body mass index (BMI) has been established as a risk factor for the disease 3,4. The number of obese patients with advanced knee osteoarthritis is expected to increase in the coming decades as the prevalence of obesity among U.S. adults continues to rise 5. Patients who develop advanced knee osteoarthritis are typically offered total knee arthroplasty, a cost-effective procedure for relieving pain and restoring function 6,7. More than 660,000 total knee arthroplasty procedures were ...

<p>Being Underweight Is Associated with Worse Surgical Outcomes of Total Knee Arthroplasty Compared to Normal Body Mass Index in Elderly Patients</p>

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Early functional results of total knee arthroplasty in patients with alimentary obesity

“…Период реабилитации не отличался по результатам от такового у пациентов с нормальным ИМТ, что коррелирует с данными других исследователей [13][14][15].…”

What Have We Learned About the Course of Clinical Outcomes After Total Knee or Hip Arthroplasty?

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