The aim of this study is to compare the Competency of coupling of IPACK Block with Adductor Canal Block versus Adductor Canal Block Alone on Postoperative Pain after total knee replacement as well as Functional Recovery and Inflammatory Response and range of motion postoperatively.

Postoperative Analgesia Management and Evaluation of Outcomes:

After the total knee arthroplasty ended, the patients will be transmitted to the post anaesthesia care unit (PACU). The same multimodal postoperative analgesia will be applied in the PACU in three groups, which will be consistent with ketorolac 50 mg every twelve hours and acetaminophen 1 g i.v. every eight hours will be both applied for 3 days. If the NRS score is higher than 4, 5 mg morphine will be administered as rescue analgesia. Eight mg of odanesteron will be given when severe nausea or vomiting occurs. Enoxaparin for four weeks postoperatively will be given as a thromboembolism prophylaxis. Finally, patients will be ambulated with the help of the walker after the first ten postoperative hours.

Assessment of outcomes:

Primary outcome:

Assessment of pain after completing the surgical procedure and wear off of spinal analgesia that will be confirmed by Bromage scale and cold sensation.

The total cumulative dose of used morphine to control pain from the postoperative in post anaesthesia care unit and in orthopaedic wards. Also, total opioid consumption will be recorded at 0-6, 6-12, and 12-24 h after surgery as primary outcome of the study.

Secondary outcome:

The secondary outcomes including assessment of pain by visual analogue scale (VAS) will be done postoperatively at 8 hours, 12 hours and 24 hours postoperatively.

Visual analogue scale (VAS) (scale 0-10, where 0 = no pain and 10 = worst imaginable pain). All the patients will have the VAS score explained and taught for self-assessment of pain at the time of enrolment for the study (Bringuier et al., 2009).

As well as the range of motion and quadriceps strength will be measured to grade the functional recovery of the knee joint after surgery after the first ten hours postoperatively. The protractor will be used for the range of motion. The interval of activities will be recorded three times a day, 6 h apart, and i will use the best value as the day's value. The quadriceps strength will be measured by asking the patient to flex the hip and knee and the complete knee extension. The outcome assessor will use resistance to knee extension and palpated the thigh muscles to measure muscle strength. No muscle movement will score 0 points, no joint movement with muscle contraction will score 1 point, no gravity resistance with joint movement will score 2 points, gravity resistance will score 3 points, partial counterforce resistance with gravity resistance will score 4 points, and normal joint function will score 5 points.

Also, blood samples for neutrophil-lymphocytic ratio (NLR) and platelet-lymphocytic ratio (PLR) will be collected at 12 and 24 h after surgery.

Inclusion Criteria:

• Patients undergoing total knee replacement.
• ASA physical status I to III
• Sex (males and females).
• Age 20 - 70 years.

Exclusion Criteria:

• Patients undergoing bilateral or revision total knee replacement.
• ASA physical status more than III
• Age less than 20 or older than 70
• severe renal insufficiency ( Estimated Glomerular filtration rate eGFR < 15 mL/min/1.73 m2 ).
• history of arrhythmia or seizures.
• Hypersensitivity to local anesthetics.
• Preexisting peripheral neuropathy and prior vascular surgery on femoral vessels on operated site.
• Infection near site of injection e.g. osteomyelitis, septic knee joint, etc.
• Patient refusal or with difficulties in comprehending numeric pain rating scale (NRS) pain scores
• Any contraindications for spinal anesthesia. (eg.: refusal of patients, coagulopathy, use of anticoagulants or antiplatelets...)