A Comparative Evaluation of Combined Nerve Block Versus Periarticular Infiltration on Postoperative Pain Relief in Total Hip Arthroplasty

IntroductionTo minimize the side effects of the central neuraxial blockade to obtain postoperative pain relief, there has been an increasing preference for targeting the peripheral structures in patients undergoing total hip arthroplasty (THA).Patients and MethodsThis prospective study was performed between September 2019 and September 2021 and involved 30 patients that were randomized to two groups. One group (n = 15) received combined nerve block (CNB) [obturator nerve, nerve to quadratus femoris, superior gluteal nerve, and femoral nerve], while another group (n = 15) received periarticular infiltrative analgesia (PIA). All the patients were given the same volume and composition of the drug cocktail (20 ml 0.5% ropivacaine, 1 ml (100 mcg) dexmedetomidine, and 29 ml normal saline).ResultsThe patients in group CNB had a significantly lower visual analog score (VAS) at 6, 12, 18, 24, 30, 36, 42 and 48 h after surgery (p < 0.05). Patients in group CNB required fewer (p < 0.001) doses of the rescue analgesic (1.67 +/- 0.90 doses) as compared to group PIA (3.53 +/- 0.64 doses). Time to the first rescue analgesia was significantly longer (p = 0.01) in group CNB (6.71 +/- 2.36 h) as compared to group PIA (4.80 +/- 1.26 h). However, patients in group PIA had significantly faster sensory (p < 0.001) and motor recovery (p < 0.001) as compared to group CNB. It took significantly longer (p < 0.001) to administer the nerve block (16.87 +/- 1.80 min) as compared to periarticular infiltration (6.53 +/- 1.18 min). There were no complications in either group.ConclusionCNB registered significant superiority over PIA with respect to postoperative pain relief and time to rescue analgesia. However, the time taken to administer CNB was significantly higher and the patients in the PIA group had early recovery in sensory and motor modalities.