Total knee arthroplasty (TKA) surgery is associated with severe pain. The success of knee rehabilitation following surgery depends largely on adequate pain control that permits early physical therapy. Postoperative modern analgesic recommendations specific to TKA propose either spinal block with intrathecal morphine (ITM) or a combination of general anesthesia with single shot femoral nerve block (SFNB). Femoral nerve block (FNB) too has proven analgesic advantages in TKA surgery. However, we do not know if the combination of the two analgesic techniques, ITM and peripheral nerve blocks (PNB), provides superior analgesia to ITM alone.