Personality traits predict residual pain after total hip and knee arthroplasty

Aim of the study: We assessed the role of personality traits, anxiety, and depression in residual pain among patients who underwent total hip (THA) and knee (TKA) arthroplasty.

Method: Eighty-three patients (40 THA and 43 TKA) were interviewed pre-operatively (t₀); five days (t₁) after surgery; and one (t₂), three (t₃), six (t₄), and 12 months (t₅) after surgery. Personality (TCI-R), pain (VAS), anxiety and depression (HADS), quality of life (SF-12), functionality (HHS/KSS), and disability (WOMAC) were evaluated.

Results: Pain reduction and functional improvement were reported at t₅ (both p < 0.001) in both THA and TKA patients. THA patients showed earlier and greater functional improvement after surgery (both p < 0.001) in comparison with TKA. Residual pain (VAS > 30 mm) was noted in 15% of the THA patients and 25% of the TKA patients, and it correlated with the SF-12 PCS (r² = - 0.412; p < 0.001), SF-12 MCS (r² = - 0.473; p < 0.001), HADS-A (r² = 0.619; p = <0.001), HADS-D (r² = 0.559; p < 0.001), functionality (r² = - 0.482; p < 0.001), and WOMAC (r² = 0.536; p < 0.001) scores at t₅. High pre-operative harm avoidance, persistence, and anxiety scores were predictive of residual pain after both THA and TKA (p < 0.001).

Discussion: The proportion of patients complaining of residual pain in this study was similar to that in previous findings. Multiple predictors of residual pain after THA and TKA have been previously described, and several studies evaluated the influence of psychological factors on the outcome of joint arthroplasty; however, only four studies investigated the role of personality traits in the outcome of THA and TKA patients, and a unique study out of these investigations demonstrated the effect of personality on persisting pain.

Conclusion: The current study demonstrated that personality traits and anxiety predict residual pain; thus, pre-operative evaluation of these factors could be helpful in identifying patients at risk for residual pain.