Obesity Class and Clinical Response to Multidisciplinary Weight Management in Patients with Knee Pain: A Retrospective Study
Objective: To determine the impact of reducing body mass index (BMI) and differences between obesity classes in obese patients with knee pain.
Methods: This retrospective research examined ninety-three obesity center patients with complete 9-month data, including monthly weight, BMI, Visual Analog Scale (VAS), and functional status assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) assessments, who were included in the analysis. Participants were classified as obesity class I (30.0-34.9 kg/m²), class II (35.0-39.9 kg/m²), or class III (≥40.0 kg/m²). We studied pain and function changes associated with percentage BMI decrease.
Results: Mean age was 50.3±11.0 years. Median BMI was 36.74 kg/m² (IQR: 33.94–40.75). All obesity groups had significant reductions in BMI, VAS and WOMAC scores, at month 9 compared to baseline (P<0.001). The magnitude of BMI reduction did not differ between groups (P=0.155). VAS and WOMAC improvements differed by category (VAS; P=0.009; WOMAC; P=0.004), with the smallest improvement in class III. Holm-corrected comparisons showed differences between class I and class III for VAS (P=0.007) and WOMAC (P=0.004), and between class II and class III for WOMAC (P=0.042). A weak association was observed between percentage BMI reduction and WOMAC improvement (rho=0.262; P=0.011), but not VAS improvement (rho=0.008; P=0.941).
Conclusion: BMI reduction was associated with improvements in pain and functional status over 9 months in patients with obesity and knee pain. However, symptomatic improvement was less pronounced in class III obesity despite a similar magnitude of BMI reduction. These findings suggest that obesity severity may influence clinical response and that patients with advanced obesity may require more individualized and comprehensive management strategies.
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Article Information
- Article Type Research Article
- Submitted March 14, 2026
- Accepted May 24, 2026
- Published June 16, 2026
- Issue 2026: Online First
- Section Research Article
- Categories
