Local infiltration analgesia improves functional outcome after total knee arthroplasty: A randomized controlled trial

Abstract

Background: Total knee arthroplasty (TKA) may be associated with severe postoperative pain, which requires prolonged hospital stay to provide effective analgesia. Increasing postoperative pain is associated with increased hospital stays and readmissions, lower patient satisfaction, longer time to rehabilitation and physiotherapy milestones and diminished range of motion (ROM). Purpose: This randomized controlled trial compared the functional outcome following the use of local infiltration analgesia (LIA) with combined spinal epidural analgesia (CSEA) versus CSEA alone in patients undergoing primary unilateral osteoarthritis of the knee. Methods: Between December 2017 and June 2019, a total of 30 patients undergoing primary unilateral TKA were included in the study. The patients were randomized into two groups, 15 patients each. Patients in Group A were administered LIA intraoperatively while patients in Group B were not. Both groups were given CSEA as their primary modality of anesthesia. Primary outcome was ROM of knee on 1st, 5th, and 14th postoperative days. Secondary outcomes were pain assessment using visual analog scale score on 6th, 24th, and 48th h postsurgery, total opioid consumption in 1st 48 h, and duration of hospital stay. Results: Mean ROM at 1st, 5th and 14th day was significantly higher in Group A compared to Group B (P < 0.05 for all). Mean pain score at 6 h, 24 h, and 48 h was significantly higher in Group B compared to Group A (P < 0.05 for all). Mean total opioid consumption was significantly higher in Group B (455.20 ± 38.84 g) compared to Group A (325.73 ± 50.18 g) (P < 0.001). Mean duration of hospital stay was significantly higher in Group B (7.07 ± 0.96 days) compared to Group A (5.73 ± 0.59 days) (P < 0.001). Conclusion: LIA provides significant pain relief in the early postoperative period and hence is associated with higher patient satisfaction. LIA also allows early and improved pain-free ROM at knee and contributes to achieving rehabilitation milestones earlier. It significantly reduces opioid requirement and thus reducing opioid-related side-effects.