Abstract
BACKGROUND: Nerve blocks are effective in reducing postoperative opioid use and enhancing rehabilitation following total knee arthroplasty. However, few studies compare the analgesic efficacy and functional recovery of adductor canal block (ACB) combined with infiltration between the popliteal artery and the capsule of the knee (iPACK) versus sciatic and femoral nerve blocks (S + F). This study hypothesized that ACB combined with iPACK (A + I) provides comparable analgesia to S + F with superior motor recovery. METHODS: Data were obtained from a prospectively maintained acute pain service database. After exclusion criteria were applied, 126 patients were analyzed. Propensity-score matching balanced baseline characteristics between the A + I and S + F groups. Numeric rating scale (NRS) scores at different time points were primary outcome. Motor function analysis, including the motor blockade, maximum flexion angle and time to ambulation were secondary outcomes. RESULTS: After propensity score matching, patients in the A + I group reported significantly lower NRS pain scores in the post-anesthetic care unit (1.00 ± 0.72 vs. 1.52 ± 1.34; P = 0.026) and on postoperative day 1 at rest (0.66 ± 0.71 vs. 1.07 ± 0.95; P = 0.025) and during movement (1.75 ± 0.75 vs. 2.43 ± 1.19; P = 0.002). Movement-associated pain on postoperative day 2 was also lower in the A + I group (1.45 ± 0.66 vs. 2.34 ± 0.91; P < 0.001). The A + I group exhibited significantly less motor blockade (P < 0.001) and achieved earlier ambulation (1551.75 ± 379.98 vs. 2031.95 ± 764.77 min; P < 0.001). CONCLUSIONS: The A + I regimen demonstrated superior analgesic efficacy, reduced motor blockade, and earlier ambulation compared to S + F in TKA patients. These findings support the use of A + I for improved recovery. TRIAL REGISTRATION: This trial was registered before collection of data and analysis at ClinicalTrials.gov (NCT06521619). Date of registration: 2024-07-26.