Influence of Anatomical Alignment on Pharmacological Response and Functional Outcomes Following Conservative Management of Knee Osteoarthritis

Abstract

Background: Knee osteoarthritis (KOA) is a progressive musculoskeletal disorder characterized by pain, functional impairment, and reduced quality of life. Anatomical alignment of the lower limb is an important biomechanical factor that may influence disease progression and the effectiveness of conservative pharmacological management.

Objective: To evaluate the influence of anatomical alignment on pharmacological response and functional outcomes among patients undergoing conservative treatment for knee osteoarthritis.

Methods: A cross-sectional analytical study was conducted involving 180 patients with radiographically confirmed knee osteoarthritis managed conservatively. Participants were categorized according to lower limb alignment into varus (n = 82), neutral (n = 46), and valgus (n = 52) groups using standing anteroposterior radiographs. All patients received standard pharmacological therapy consisting of nonsteroidal anti-inflammatory drugs (NSAIDs) with or without acetaminophen, along with physiotherapy and lifestyle modification. Pain intensity was assessed using the Visual Analog Scale (VAS), functional status using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and physical performance using the Timed Up and Go (TUG) test after 12 weeks of treatment. Statistical analysis was performed using one-way ANOVA, chi-square test, and multivariate linear regression. A p-value <0.05 was considered statistically significant.

Results: Patients with neutral alignment demonstrated significantly greater improvement in pain and function compared with those having varus or valgus deformities. Mean reduction in VAS score was 3.8 ± 1.1 in the neutral group compared with 2.4 ± 1.0 in the varus group and 2.7 ± 1.2 in the valgus group (p < 0.001). WOMAC total scores improved by 39.6%, 24.8%, and 27.3%, respectively (p = 0.002). The mean TUG time improved from 12.3 ± 2.5 s to 9.8 ± 2.1 s in the neutral group, whereas improvements were significantly smaller in varus and valgus groups (p = 0.004). Multivariate regression identified varus malalignment as an independent predictor of poorer pharmacological response (β = 0.34, p = 0.001) after adjusting for age, sex, body mass index, and disease severity.

Conclusion: Anatomical alignment significantly influences the clinical response to conservative pharmacological management in knee osteoarthritis. Patients with neutral lower limb alignment achieved superior pain relief and functional recovery, whereas varus and valgus malalignment were associated with reduced treatment effectiveness. Incorporating anatomical alignment assessment into routine clinical evaluation may facilitate individualized treatment strategies and improve patient outcomes.