Frontal plane knee alignment mediates the effect of frontal plane rearfoot motion on knee joint load distribution during walking in people with medial knee osteoarthritis

Hunt, MA; Charlton, JM; Felson, DT; Liu, A; Chapman, GE; Graffos, A; Jones, R

Abstract

Objective
To examine the nature of differences in the relationship between frontal plane rearfoot kinematics and knee adduction moment (KAM) magnitudes.

Design
Cross-sectional study resulting from a combination of overground walking biomechanics data obtained from participants with medial tibiofemoral osteoarthritis at two separate sites. Statistical models were created to examine the relationship between minimum frontal plane rearfoot angle (negative values = eversion) and different measures of the KAM, including examination of confounding, mediation, and effect modification from knee pain, radiographic disease severity, static rearfoot alignment, and frontal plane knee angle.

Results
Bivariable relationships between minimum frontal plane rearfoot angle and the KAM showed consistent negative correlations (r = -0.411 to -0.447), indicating higher KAM magnitudes associated with the rearfoot in a more everted position during stance. However, the nature of this relationship appears to be mainly influenced by frontal plane knee kinematics. Specifically, frontal plane knee angle during gait was found to completely mediate the relationship between minimum frontal plane rearfoot angle and the KAM, and was also an effect modifier in this relationship. No other variable significantly altered the relationship.

Conclusions
While there does appear to be a moderate relationship between frontal plane rearfoot angle and the KAM, any differences in the magnitude of this relationship can likely be explained through an examination of frontal plane knee angle during walking. This finding suggests that interventions derived distal to the knee should account for the effect of frontal plane knee angle to have the desired effect on the KAM.

Citation

Hunt, M., Charlton, J., Felson, D., Liu, A., Chapman, G., Graffos, A., & Jones, R. (2021). Frontal plane knee alignment mediates the effect of frontal plane rearfoot motion on knee joint load distribution during walking in people with medial knee osteoarthritis. Osteoarthritis and Cartilage, 29(5), 678-686. https://doi.org/10.1016/j.joca.2021.02.003

• Journal Article Type: Article
• Acceptance Date: Feb 1, 2021
• Online Publication Date: Feb 12, 2021
• Publication Date: May 1, 2021
• Deposit Date: Feb 17, 2021
• Publicly Available Date: Feb 12, 2022
• Journal: Osteoarthritis and Cartilage
• Print ISSN: 1063-4584
• Publisher: Elsevier
• Volume: 29
• Issue: 5
• Pages: 678-686
• DOI: https://doi.org/10.1016/j.joca.2021.02.003
• Publisher URL: https://doi.org/10.1016/j.joca.2021.02.003
• Related Public URLs: https://www.journals.elsevier.com/osteoarthritis-and-cartilage/
• Additional Information: Funders : The Arthritis Society (Canada);The Pedorthic Research Foundation of Canada;NIHR Manchester Musculoskeletal Biomedical Research Centre;Centre for Epidemiology Versus Arthritis;Arthritis Research UK Special Strategic Award;The National Institutes of Health; Grant Number: SOG-13-024; Grant Number: 20380; Grant Number: 18676; Grant Number: P30AR72571