THE ANALGESIC EFFICACY OF A STANDARDIZED LOCAL INFILTRATION ANALGESIA TECHNIQUE OVER EQUIVALENT EPIDURAL ANALGESIA IN TOTAL KNEE ARTHROPLASTY AND A COMPARATIVE ANALYSIS WITH MOST CITED RCTs

Abstract

Background: Managing postoperative pain in TKA is a challenge and needs an imperative strategy to bring maximal knee function early, with minimal side effects and less hospital stay. Though local infiltration analgesia emerged as a potent alternative, consensus on whether local infiltration analgesia offers clinically relevant pain relief is still lacking due to inconsistent studies and lack of standardization. The present study is an attempt to deduce the analgesic efficacy of a standardized single-shot local infiltration analgesia (LIA) with epidural analgesia with comparative analysis of previous most cited studies. Study Design & Methods: This is a prospective, randomized clinical trial done in n=74 patients with moderate to severe arthritis (Mean OKS - 15.24, SD 6.153) undergoing unilateral primary TKA in the south Indian population in a single center. The choice of analgesia, surgical technique, postoperative medications, and rescue analgesia and rehabilitation protocol on both groups are kept identical. In the LIA group, the CPN area is carefully avoided. The primary outcome is postoperative pain at rest and at activity, knee flexion and mobilization time quantified for 72hrs postoperatively. The student t-test, the chi-square test is used for analysis. Results: The LIA group had significantly lower mean VAS scores at rest (P = <0.001) and during activity (p= < 0.001) for 72 hrs postoperatively, and the mean difference in knee flexion angle is low (7.20 ± 1.07) yet higher in LIA on D0 and a significantly better knee flexion angle is noted at postoperative D1 & D2 (P=0.001, 0.005). The mobilization time is significantly lower in the LIA group (P = <0.001) with a mean difference of 14.50 ± 6.236 hrs. Conclusions: The multimodal local infiltration analgesia offers better pain relief, ROM and earlier mobilization than epidural analgesia if consistently standartized, facilitating rehabilitation and early return to day to day activities with lesser side effects and no transient peroneal nerve palsy if used methodically.