Nielsen et al. reported that when iliopsoas plane block was performed on healthy volunteers, the injection solution in Hip MRI was confined to the myofascial compartment, which was known to include all sensory branches of the femoral nerve that control the hip joint. The maximal muscle strength of knee extension did not decrease before and after Iliopsoas plane block in Volunteer. Since there is no clinical study conducted on patients after the volunteer study, the investigators intend to evaluate the analgesic and motor preserving effects of the iliopsoas plane block in a group of patients undergoing total hip arthroplasty.

Inclusion Criteria:

1. Patients 19 years of age or older who are expected to undergo unilateral hip arthroplasty
2. ASA PS 1-3

Exclusion Criteria:

1. Revision total hip arthroplasty
2. Allergy to drugs used in the study
3. Patients with moderate or more hepatic impairment (AST/ALT is more than 2.5 times the upper limit of normal)
4. Estimated glomerular filtration rate < 30 mL/min/1.73m2
5. Opioid dependence
6. Prolongation of PT and aPTT more than twice the upper limit of normal
7. Pre-existing neurological or anatomical disorders of the lower extremities
8. Serious psychiatric disorders

Double