A randomized, controlled trial on the effect of anesthesia on chronic pain after total knee arthroplasty

Aim: The study sought to evaluate the influence of anesthesia on chronic pain after total knee arthroplasty (TKA). Methods: This was a single-center, randomized controlled study, with patients receiving a spinal anesthetic (SP) alone or a general anesthetic (GA) with femoral block, with follow-up at 3 and at 6 months. The primary outcome was the WOMAC^® score at 6 months. Results: 199 patients were enrolled. Group SP had better function (WOMAC: GA: 16.9 vs SP: 14.4, p = 0.015) and less pain (WOMAC pain: GA: 3.04 vs SP: 2.69, p = 0.02) at 3 months, but not at 6 months. Overall, 11% of patients had chronic postsurgical pain (CPSP), with Group GA having a higher incidence of CPSP at 6 months. Neuropathic pain increased during the follow-up and was more common in patients with CPSP. Conclusion: An SP reduces pain and incidence of CPSP after TKA. Clinical Trial Registration: NCT04206046 (ClinicalTrials.gov).