Factors influencing knee adduction moment measurement: A systematic review and meta-regression analysis

• Published in: Gait & posture Vol. 58; pp. 333 - 339
• Main Authors: Telfer, Scott, Lange, Moritz J., Sudduth, Amanda S.M.
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01-10-2017
• Subjects: Footwear; Humans; Knee adduction moment; Knee Joint - physiopathology; Knee osteoarthritis; Meta-regression; Osteoarthritis, Knee - physiopathology; Range of Motion, Articular - physiology; Walking - physiology; Walking speed; Walking Speed - physiology; Meta-regression; Knee adduction moment; Knee osteoarthritis; Walking speed; Footwear
• ISSN: 0966-6362; 1879-2219
• DOI: 10.1016/j.gaitpost.2017.08.025

•We performed a meta-regression analysis of external knee adduction moment (KAM) data.•The effect of population type, footwear type, and walking speed were determined.•Controlling for other moderators, walking speed had the largest effect on the measurement.•Subjects in standardized footwear had a higher KAM than those tested barefoot or in their own shoes.•Participants with medial knee osteoarthritis had higher KAMs than healthy individuals.
The external knee adduction moment has been identified as a key biomarker in biomechanics research, with associations with this variable and degenerative diseases such as knee osteoarthritis. Heterogeneity in participant characteristics and the protocols used to measure this variable may however complicate its interpretation. Previous reviews have focused on interventions or did not control for potential moderator variables in their analysis. In this meta-regression analysis, we aimed to determine the influence of factors including the cohort type, footwear, and walking speed on the measurement of knee adduction moment. We performed a systematic review of the literature, identifying articles that used the Plug-in-Gait inverse dynamics model to calculate the knee adduction moment during level walking, and used a mixed effect model to determine the effect of the previously described factors on the measurement. Results for 861 individuals were described in 19 articles. Walking speed had the largest influence on knee adduction moment (p<0.001), and participants with medial knee osteoarthritis had an increased knee adduction moment (p=0.008) compared to healthy subjects. Footwear was found to have a significant overall effect (p=0.024). Participants tested barefoot or wearing their own shoes had lower adduction moments than those tested in footwear provided by the researchers. Overall, the moderators accounted for 60% of the heterogeneity in the results. These results support the hypothesis that an increased knee adduction moment is associated with medial compartment knee osteoarthritis, and that footwear choice can influence the results. Gait speed has the largest effect on knee adduction moment measurement and should be carefully controlled for in studies investigating this variable.