IPACK Block After Total Knee Arthroplasty

Comparison of Adductor Canal Block and IPACK Block With Adductor Canal Block Alone After Total Knee Arthroplasty

Adductor canal block (ACB) is a peripheral nerve blockade technique that provides good pain control in patients undergoing total knee arthroplasty (TKA) which however does not relieve posterior knee pain. The recent technique of an ultrasound-guided local anesthetic infiltration of the interspace between popliteal artery and the capsule of posterior knee (IPACK) has shown promising results in providing significant posterior knee analgesia without affecting the motor nerves. The hypothesis was that the combination of ACB + IPACK will provide better pain relief and improve knee function in the immediate postoperative period compared to ACB alone.

This is a prospective, randomized and double blinded study All patients received : Pregabalin 150 mg preoperatively 12 h before the surgery. Single-shot spinal anesthesia with 10 to 12 mg of bupivacaine 0.5% and 2.5ug sufentanil patients were randomly allocated to receive: Group 1: IPACK + ACB single shoot Group 2: contineous ACB For group 1: IPACK was realized after spinal anesthesia with 40 ml ropivacaine 0.2% All patients received ACB in the immediate postoperative period with 20 ml ropivacaine 0.2% Post operative analgesia included: Paracetamol 1g IV every 6 hours Diclofenac sodium (50mg) 1 tablet x 2 per day Pregabalin 150 mg given orally once daily for a period of 4 weeks. PCA morphine (Patient Controlled Analgesia), as a rescue analgesia, Continuous ACB catheter for 48H with : 4 ml per hour 0.2% ropivacaine in group 2 4 ml per hour saline in group 1

ACB was done in the immediate postoperative period under a high-frequency ultrasound guidance in which the adductor canal was identified beneath the sartorius muscle and 20 ml of 0.2% ropivacaine was injected in the canal using a 22-gauge 100-mm short-beveled regional block needle and a catheter was kept for 48H with 4 ml/h ropivacaine 0.2%.

IPACK was realized after spinal anesthesia. Patient was placed in a supine position and knee placed in position of 90° flexion. A low-frequency ultrasound probe was positioned in the popliteal crease, and the needle was inserted from medial aspect of the knee from anteromedial to posterolateral direction in a plane between the popliteal artery and the femur. The tip of the needle was placed 1-2 cm beyond the lateral edge of the artery, and 20 ml of 0.2% ropivacaine was injected for each side. A ACB was done postoperatively with 20 ml ropivacaine 0.2% and a catheter was kept for 48H with 4 ml/h saline

ACB was done in the immediate postoperative period under a high-frequency ultrasound guidance in which the adductor canal was identified beneath the sartorius muscle and 20 ml of 0.2% ropivacaine was injected in the canal using a 22-gauge 100-mm short-beveled regional block needle and a catheter was kept for 48H with 4 ml/h ropivacaine 0.2%.

IPACK block was realized after spinal anesthesia with 40 ml 0.2% ropivacaine and at the end of surgery , patients were given ACB with 20 ml 0.2% ropivacaine and continued with 4 ml/H saline for 48H

Inclusion Criteria: primary total knee arthroplasty under spinal anesthesia Exclusion Criteria: Contraindication or refusal to regional anesthesia Contraindication to non steroidal anti inflammatory (NSAID's) Allergy to opioids Allergy to paracetamol Creatinine clearance < 30ml/min Weight<50 kg or >100kg