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.

All patients will be operated under spinal anaesthesia with 2.0-3.0 ml Bupivacaine 0.5 % plain, preferably at the L2/L3 alternatively the L3/L4 vertebral interspace. Propofol infusion will be administrated for sedation if needed. Postoperative morphine will be given as needed intravenously when needed. After transfer to a specialized hip arthroplasty unit with a well-defined and experienced program for multimodal rehabilitation, multimodal oral opioid-sparing analgesia will be given to all patients; NSAIDS and Acetaminophen will be given at regular intervals and Oxycodone as needed.