Patient has undergone open surgery for a left total knee arthroplasty.

The patient has undergone a left total knee arthroplasty and subsequently received a femoral nerve block for postoperative pain management. CPT code 01402 is used for anesthesia for total knee arthroplasty. Code 64447-59-LT is for a femoral nerve block (single injection) for postoperative pain management, with modifier 59 indicating a distinct procedural service and LT indicating the left side. Therefore, the appropriate codes are 01402 and 64447-59-LT.