Postoperative Psychological Predictors for Chronic Postsurgical Pain After a Knee Arthroplasty: A Prospective Observational Study

Abstract

Objective Chronic postsurgical pain is a significant adverse effect shown in around 20% of people who had undergone a knee arthroplasty. Psychological risk factors emerged as significant and potentially modifiable risk factors for its development. However, there is still little evidence when assessing these factors during the acute postoperative period. This study aimed to assess the predictive value of postoperative pain catastrophizing, pain-related fear of movement, anxiety, depression, and pain attitudes in developing chronic postsurgical pain after knee arthroplasty.

Methods A 6-month follow-up prospective observational study design was used. The study sample comprised 115 people who underwent a knee arthroplasty due to painful primary osteoarthritis. Measures of pain catastrophizing, pain-related fear of movement, anxiety, depression, and pain attitudes were obtained 1 week after surgery. Chronic postsurgical pain was set at an intensity of ≥30 using a 100-mm visual analog scale 3 and 6 months after surgery.

Results Analysis revealed that baseline pain intensity, pain catastrophizing, pain-related fear of movement, anxiety, depression, and maladaptive pain attitudes were significant predictors of chronic pain at 3 and 6 months after surgery in a univariate analysis. However, at 3 months after surgery, only pain intensity and pain catastrophizing were predictors in the final multivariate model forecasting disturbing pain. Moreover, 6 months after surgery, pain intensity and distrust in medical procedures remained independent predictors. Most of the psychological factors can be grouped into a single dimension defined as pain-related psychological distress.

Conclusion The results suggest that postoperative pain intensity, pain catastrophizing, and pain attitudes are independent predictors for chronic postsurgical pain after knee arthroplasty.

Impact Postoperative cognitive and emotional factors should be considered alongside pain intensity during postoperative rehabilitation after knee arthroplasty since they could influence the development of chronic postsurgical pain.