The determinants of outcomes and the scope of outcomes examined in total joint replacement (TJR) typically have been limited to aspects of physical health. We investigated mental well-being, physical and social health, and self-rated health (SRH) as predictors of future health status within a cohort undergoing a TJR for hip or knee osteoarthritis. We also investigated the interrelationships among these health dimensions as they relate to SRH.
Participants (n = 215 hip, n = 234 knee) completed measures presurgery and 3 and 6 months postsurgery, including pain, physical function, fatigue, anxiety, depression, social participation limitations, passive/active recreation, community mobility, and SRH. Structural equation modeling was used to investigate the interrelationship between 3 latent health dimensions (physical, mental, social) and the predictive significance of SRH for future health status.
The mean age was 63.5 years (range 31-88 years) and 60% were women. Prior dimension status strongly predicted future status. Adjusted for prior dimension scores, comorbidity, and sociodemographic characteristics, SRH predicted future scores for all 3 health dimensions. Worse prior SRH predicted less improvement at all time points. The effects of physical and social health on SRH were fully mediated through mental well-being. Only mental well-being significantly predicted SRH, within and across time.
Mental well-being is critical for understanding the relationship between physical health and SRH. In addition, SRH significantly predicts TJR outcomes, above and beyond prior physical health. The exclusive focus on any one health dimension may lead to missed opportunities for predicting and improving outcomes following surgery, and likely improving overall health generally.