Abstract
This trial examined the effectiveness of the popliteal plexus block (PPB) and tibial nerve block (TNB) for early rehabilitation after total knee arthroplasty (TKA). We allocated 136 participants to receive PPB or TNB with 0.25% levobupivacaine 10 mL in a randomized, double-masked manner. The primary outcome was achieving rehabilitation goals with a non-inferiority 9-hour margin, including adequate pain relief, knee flexion angles over 90 degrees, and enabling ambulatory rehabilitation. The time to reach rehabilitation goals showed non-inferiority with 49.7 ± 10.5 h for TNB and 47.4 ± 9.7 h for PPB, whose mean difference (PPB - TNB) was - 2.3 h (95% CI -5.8 to 1.2 h; P < 0.001). PPB showed higher dorsal and plantar percentage of maximum voluntary isometric contraction (dorsal, PPB 87.7% ± 11.4% vs. TNB 74.0% ± 16.5%: P < 0.001; plantar, PPB 90.9% ± 10.3% vs. TNB 72.1% ± 16.0%; P < 0.001) at six hours after nerve block. No significant differences between the two groups emerged in pain scores, knee range of motion, additional analgesic requirements, success in the straight leg raise, and adverse events. PPB exhibited non-inferiority to TNB in achieving postoperative rehabilitation goals and had superiority in preserving foot motor strength after TKA. (200).