The purpose of this study is to learn if using a suprainguinal fascia iliaca (SIFI) injection technique (also called a "nerve block") that numbs the nerves going to the side and front of the upper leg will improve pain control after surgery. The SIFI technique uses a numbing solution (local anesthetics) that is injected next to nerves in the hip to reduce pain. This block may affect movement in the leg and make the legs weak. The amount of leg weakness is not known and assessment of this will be included in the study. Many institutions use the SIFI block for patients having total hip replacements, with the hope of providing good pain relief combined with improved mobility after surgery.