Pain after total hip replacement (THR) surgery is severe. The target population is elderly and comorbid. Level III analgesics are responsible for significant side effects in this population. Locoregional analgesia, by reducing the consumption of painkillers, is an effective way of reducing morphine or morphine agonist consumption in this surgery. Furthermore, these techniques fit in perfectly with the objectives of accelerated rehabilitation after surgery. Surgical infiltration is a frequently used and effective analgesic technique. PENG block is a new locoregional anesthesia technique which initial results show promising analgesic efficacy and the absence of loss of strength through motor block. In February 2022, we carried out a survey of national anesthetic practices in posterior hip arthroplasty, with the help of the SFAR (Société Française d'Anesthésie-Réanimation). It shows that, despite the lack of plentiful literature on the subject, the PENG block is currently the most frequently performed pre-operative block in hip arthroplasty (PENG block in 39.5% of cases, femoral block in 13% of cases). The survey also shows that in 41.5% of cases, no block is performed, and only intraoperative surgical infiltration is carried out. PENG block and surgical infiltration are therefore the two analgesic techniques most frequently used in France today. It is for these reasons that we feel it is essential to carry out a study comparing these two techniques.