This study employs a randomized controlled trial to investigate whether bupivacaine liposome injection for adductor canal block can effectively improve lower limb muscle strength after total knee arthroplasty.
Patients aged 60-75 years scheduled for elective TKA;
ASA physical status classification II-III;
BMI 18-30 kg/m²;
Agreement to participate in this study and provision of signed informed consent.
Individuals with communication barriers such as language or hearing impairments;
Patients with contraindications to nerve blocks;
Severe systemic diseases, such as severe renal disease (estimated glomerular filtration rate below 50 mL/min), cardiac disease (congestive heart failure New York Heart Association Class III to IV), or severe hepatic disease defined as a current or past diagnosis of acute/subacute hepatic necrosis, acute liver failure, chronic liver disease, liver abscess, hepatic coma, or hepatorenal syndrome;
History of long-term opioid use (defined as daily or nearly daily opioid use within the past 3 months).