Structural equation model of knee pain in individuals with knee osteoarthritis-associated knee pain, based on functional capacity, kinesiophobia, muscle thickness, and joint position sense

Abstract

Background: There are several clinical parameters that contribute to knee osteoarthritis (KOA)-associated knee pain and/or its progression such as kinesiophobia, functional capacity, muscle thickness, and joint position sense. The relationship between knee pain and those aforementioned clinical parameters is needed for clear understanding. Therefore, this study constructed the structural equation model of knee pain with the variables of kinesiophobia, functional capacity, muscle thickness, and joint position sense in individuals with KOA-associated knee pain. Methods: We examined 200 individuals (74% female) with KOA-associated knee pain. Kinesiophobia, functional capacity test, quadriceps and hamstring muscle thickness, and knee joint position sense in flexion and extension were obtained and served as latent variables to investigate causal relationships with knee pain through structural equation modeling. Results: All latent variables were fit for the structural model with excellent statistical parameters. The squared multiple correlations’ estimate for the model was 0.928. In particular, kinesiophobia, functional capacity test, and hamstring muscle thickness had significant associations with knee pain. Conclusion: Knee pain was associated with kinesiophobia, functional capacity, quadriceps and hamstring muscle thickness, and knee joint position sense. Although this relationship does not establish causality, the findings underscore the importance of adopting an integrated approach when designing preventive interventions or therapeutic strategies for managing knee pain.