Background: Multimodal systemic analgesia plays an essential role in controlling postoperative pain after Total Knee Arthroplasty (TKA) by controlling the inflammatory process, dealing with the neuropathic component of pain. Single injection modified 4 in 1 block technique was aimed to block four nerves (saphenous nerve, obturator nerve, nerve to vastus medialis and sciatic nerve) through a single injection by spreading into the adductor canal and popliteal fossa. We hypothesized that the single injection modified 4 in 1 block would decrease postoperative total morphine consumption at first 24 hours postoperatively. Aim: To evaluate the quality of postoperative analgesia produced by single injection modified 4 in 1 block and midsartorius adductor canal block