Total Periarticular Infiltration Vs Posterior Periarticular Infiltration Plus PENG Block for Hip Analgesia

In a recent study, direct periarticular local anesthetic infiltration (PAI) showed a greater incidence of early quadriceps weakness (33% at 3 hours and 13% at 6 hours) than pericapsular nerve group block (PENGB) in total hip arthroplasty (THA) but, in turn, demonstrated a statistically significant better pain control. Additionally, PENGB could not completely circumvent motor compromise either, particularly at 3 hours (20% incidence), probably secondary to an injectate migration towards the femoral nerve. Posteriorly to this publication, a cadaveric trial looking into the maximum effective volume that spared the femoral nerve resulted in 13.2 mL. This newer evidence led to the design of a strategy that combines both interventions, aiming to obtain the best of them and have a solid alternative for those cases where very early mobilization is pursued. Thus, it is hypothesized that posterior PAI added to a low-volume PENGB (10mL) represents a superior alternative to PAI in terms of strength preservation and provides effective analgesia during the first 24 postoperative hours after THA.