Effect of Local Infiltration Anesthesia With Ropivacaine on Pain After Primary Total Hip Arthroplasty

150 ml Ropivacaine 2mg/ml + 0,5 ml Epinephrine 1 mg/ml: The first 50 ml will be injected in the periacetabular tissue after insertion of the acetabular component. After insertion of the femoral component, 50 ml will be inserted in the gluteus muscles and the proximal part of the iliotibial tract. The last 50 ml will be inserted in the subcutaneous layer.

150 ml 0,9% saline: The first 50 ml will be injected in the periacetabular tissue after insertion of the acetabular component. After insertion of the femoral component, 50 ml will be inserted in the gluteus muscles and the proximal part of the iliotibial tract. The last 50 ml will be inserted in the subcutaneous layer.