Supplementary Nerve Blocks Added to the Adductor Canal Block for Postoperative Pain Management in Primary Total Knee Arthroplasty: A Randomized Controlled Comparison of Sciatic, BiFeS, and IPACK Techniques

Postoperative pain following total knee arthroplasty (TKA) is a significant clinical problem that delays early mobilization, reduces patient satisfaction, and increases analgesic requirements. The adductor canal block (ACB), which aims to provide analgesia while preserving motor function, is widely used in postoperative pain management after TKA. However, clinical and anatomical studies have demonstrated that ACB is effective only in the anteromedial sensory innervation of the knee and does not adequately block pain originating from the posterior knee capsule. This limitation reduces analgesic effectiveness, particularly in patients with a prominent posterior pain component. The sciatic nerve block has long been considered the gold standard for managing posterior knee pain. However, due to disadvantages such as motor weakness and delayed rehabilitation, current pain management protocols increasingly favor motor-sparing and complementary approaches such as the Biceps Femoris Short Head (BiFeS) block and the Interspace Between the Popliteal Artery and the Capsule of the posterior Knee (IPACK) block for posterior knee analgesia. In light of this information, the aim of our study is to guide clinical practice by comparing the postoperative analgesic efficacy, motor function outcomes, and patient satisfaction associated with sciatic nerve, BiFeS, and IPACK block techniques-each administered as a supplement to the adductor canal block-in patients undergoing total knee arthroplasty, with the ultimate goal of determining the optimal block combination for postoperative pain control.