Patient-reported opioid dependency and reasons for use 12 months following knee arthroplasty: a prospective observational study

Background: Opioids are prescribed to alleviate pain after knee arthroplasty. However, prolonged postoperative opioid use may complicate recovery and potentially increase the risk of persistent use. This study explores opioid use following fast-track knee arthroplasty. Method: This prospective, single-center, observational study included patients scheduled for fast-track knee arthroplasty. A total of 1195 patients were included, of whom 996 underwent total knee arthroplasty (TKA) and 199 medial unicompartmental knee arthroplasty (mUKA). Participants completed a study-specific questionnaire on opioid use before surgery and at 3- and 12-month follow-up (FU). Patient-reported data at 12-month FU were available for 797 TKA (80%) and 160 mUKA (80%). Participants were categorized based on preoperative opioid use. The primary outcome was patient-reported opioid use at 12-month FU. Reasons for opioid use were also registered. Results: At 12-month FU, 3% (95% confidence interval (CI) 2–4; 24 patients) of TKA patients reported daily opioid use attributed to prosthetic knee joint pain; the proportion was higher among patients with preoperative daily opioid use (17%, CI 10–26, 17 patients) compared to those without preoperative use (1%, CI 0.2–1.5, 4 patients). 1 mUKA patient (0.6%, CI 0–3) reported daily opioid use attributed to prosthetic knee joint pain at 12-month FU. Conclusion: Persistent daily opioid use due to pain in the prosthetic knee joint was rare 12 months after fast-track TKA and mUKA. Patients with preoperative daily opioid use had a markedly higher risk of continued use compared to those without prior opioid use.