This study aimed to investigate the impact of personality traits, measured by the TIPI, on ADL in PROMs one and six months after TKA.
This cohort study included 140 patients who underwent unilateral or bilateral TKA. ADL in PROMs was assessed using the ADL subscale of the knee injury and osteoarthritis outcome score (KOOS-ADL). Personality traits were evaluated using the TIPI, which measures five traits: neuroticism, extraversion, openness, agreeableness, and conscientiousness.
Measurements were taken one month before surgery (baseline), one month (POM1) and six months (POM6) after surgery. Spearman rank correlations were used to examine the relationships between KOOS-ADL at each assessment time and each personality trait at baseline. A mixed-effects model for repeated measures was used to assess KOOS-ADL over time, including participants as a random effect and personality traits that were significantly correlated with KOOS-ADL before and after surgery as fixed effects (Model 1).
Because neuroticism had a significant impact on KOOS-ADL, participants were divided into two groups based on their neuroticism scores: the neuroticism group and the non-neuroticism group. A mixed-effects model for repeated measures (Model 2) analyzed changes in KOOS-ADL over time. Participants were included as a random effect and group, time, and group-by-time interaction terms were included as fixed effects. Age, sex, type of TKA, baseline gait speed, and baseline pain intensity were included as fixed effects in both models.
A total of 104 patients completed the follow-up assessments. Of the five personality traits measured at baseline, only neuroticism was significantly correlated with KOOS-ADL at baseline (r = -0.27, P 0.05), POM1(r = -0.34, P 0.05) and POM6 (r = -0.27, P 0.05). In Model 1, KOOS-ADL was significantly higher at POM1 (estimate = 7.72, P 0.001) and POM6 (estimate = 22.91, P 0.001) compared to baseline. Neuroticism had a significant negative main effect (estimate = -2.55, P = 0.001). In Model 2, the neuroticism group showed a significant negative main effect (estimate = -5.56, P = 0.03), although the group-by-time interaction was not statistically significant.
Our study highlights the importance of assessing personality traits before TKA, particularly neuroticism, as a predictor of postoperative ADL in PROMs. However, the recovery trajectory did not significantly differ between those with and without neuroticism.
TIPI may provide valuable insights for rehabilitation after TKA. Since patients with high neuroticism may report lower ADL in PROMs, despite actual ADL improvement, physical therapists should engage in open and patient-centered communication.
Personality
Total Knee Arthroplasty
