PAIN & OPIOID OUTCOMES FOLLOWING KNEE REPLACEMENT SURGERY

Abstract

Background: Total knee arthroplasty (TKA) and partial knee arthroplasty (PKA) are common surgical procedures for managing advanced knee osteoarthritis. Although most patients experience improved function and pain relief, a substantial subset continue to report persistent pain, dissatisfaction, or prolonged opioid use. These outcomes are not consistently addressed by standard perioperative care. Objective: This thesis aims to investigate psychological risk factors and coping behaviours for poor recovery following knee arthroplasty and to evaluate the feasibility of a multicomponent perioperative care pathway to improve long-term pain and opioid-related outcomes. Methods: The thesis includes two complementary studies. First, a prospective cohort study (SPOC Study) examined the association between maladaptive psychological traits measured using the Somatic Pre-Occupation and Coping (SPOC) questionnaire and outcomes such as chronic post-surgical pain (CPSP), opioid use, and satisfaction with care. Second, a pilot randomized controlled trial (OREOS) tested the feasibility of a multicomponent care pathway incorporating risk screening, patient education, cognitive behavioural strategies, personalized opioid prescribing, and follow-up support. Results: In the SPOC Study, higher preoperative pain scores and early postoperative SPOC scores were associated with increased risk of CPSP and dissatisfaction, underscoring the value of early risk identification. In the OREOS trial, high participant retention was achieved. However, adherence to some intervention components, particularly the behavioural skills sessions, and recruitment rates fell below pre-specified feasibility thresholds, suggesting the need for modifications before progressing to a larger trial. Conclusion: Persistent pain and opioid use remain common and often undertreated after knee surgery. Identifying psychological risk factors and implementing scalable, personalized perioperative interventions may help improve recovery and reduce harm. The findings of this thesis support a patient-centred approach to knee arthroplasty care that emphasizes behavioural support and structured postoperative follow-up.