Analgesic Efficacy of Adding SCB With Low Concentration Bupivacaine Combined With Dexamethasone on Pain After TKA

This study evaluate the efficacy of adding popliteal sciatic nerve block with low concentration bupivacaine and dexamethasone to abductor canal block for total knee arthroplasty in patient with NSAIDs prescribing precaution. Half of participants will receive popliteal sciatic nerve block, abductor canal block and periarticular injection, while the other half will receive a sham block, abductor canal block and periarticular injection.

After informed and consent, all patients will be devided into two groups, Sciatic group (group S) and Controlled group (group C). All patients will receive adductor canal block, then patients in group S will receive Sciatic nerve block with low concentration bupivacaine and dexamethasone while partients in group C will receive sham block. All patient will receive spinal anesthesia and intraoperative periarticular injection. Postoperative pain score, muscle strength, total morphine consumption and adverse events will be record in case record form.