The goal of this clinical trial is to compare the effects of femoral triangle block (FTB) and adductor canal block (ACB) on early quadriceps function after total knee arthroplasty (TKA).
The main question it aims to answer is whether FTB causes more early quadriceps functional impairment than ACB under a standardized multimodal analgesia protocol.
Researchers will compare FTB and ACB using a composite binary functional outcome measured 6 hours after block completion. Quadriceps functional impairment is defined as the inability to perform a structured straight leg raise or quadriceps muscle strength \<50% of the preoperative baseline.
Participants will be randomly assigned to receive ultrasound-guided FTB or ACB. All participants will also receive a popliteal plexus block and standardized multimodal analgesia.
Adult patients (≥ 20 years of age) are scheduled to undergo primary unilateral TKA.
American Society of Anesthesiologists (ASA) physical status I-III.
Ability to ambulate independently prior to surgery.
Ability to understand the study procedures and provide written informed consent.
Known allergy or contraindication to local anesthetic agents used in this study.
Pre-existing neurological or neuromuscular disorders affect lower limb strength or motor control.
Severe cognitive impairment or psychiatric conditions interfere with study participation or assessment.
History of revision knee arthroplasty on the operative side.