Inclusion Criteria:  Physical status according to American Society of Anesthesiologists (ASA) I-III Patients scheduled for total knee arthroplasty  Exclusion Criteria:  Previous operation on same knee Hepatic or renal insufficiency Younger than 18 years old and older than 85 Patients undergoing general anesthesia Allergy or intolerance to one of the study medications BMI > 40 ASA IV Chronic gabapentin/pregabalin use (regular use for longer than 3 months) Chronic opioid use (taking opioids for longer than 3 months, or daily oral morphine equivalent of >5mg/day for one month)