High levels of preoperative pain and fatigue are red flags for moderate‐severe pain 12 months after total knee arthroplasty—A longitudinal cohort study

Abstract

Background: Moderate/severe pain after total knee arthroplasty (TKA) is a poor surgical outcome. Many studies have identified preoperative risk factors of painafter TKA, but studies of the joint contributions of co-occurring symptoms arelacking. Methods: Patients undergoing primary TKA (n=202) were enrolled in a longitu-dinal cohort study. Preoperatively, patients completed questionnaires measuring demographics and symptoms (pain, fatigue, sleep problems and depression). Painwas re-assessed 12 months after TKA. Logistic regression analysis was used to compute the probabilities of moderate-severe pain at 12 months based on preoperative symptom levels, and results were combined into a risk matrix. Results: More than one-third (40%) of patients (n=187) reported moderate-severepain after TKA. Among preoperative risk factors included in the logistic regressionanalyses were age, sex, pain, fatigue, sleep problems and depression. Adjusting forpossible confounders, fatigue (p=0.02) and pain (p=0.01) were significant riskfactors for moderate-severe pain at 12-months follow-up and were retained in the final risk matrix. The co-occurrence of high-preoperative fatigue and pain scores resulted in 57% estimated probability of moderate-severe pain at 12 months.Similarly, the co-occurrence of low-preoperative fatigue and pain scores resulted in14% estimated probability of moderate-severe pain 12 months after TKA. Conclusion: The combination of high fatigue and pain scores prior to surgery was akey risk factor for moderate-severe pain 12 months after TKA. Mapping of these factors could be used preoperatively to identify patients who are at risk to expe-rience a poor outcome of TKA.