393: Analgesic Efficacy of Two Dual Subsartorial Block Techniques in Total Knee arthroplasty

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Acute postsurgical pain, Pharmacological treatments, Treatment/management

Background and Aims: The dual subsartorial block (DSB)—a combination of a distal femoral triangle block (FTB) and an adductor canal block (ACB)—is a motor-sparing regional anesthesia technique developed to optimize postoperative analgesia while preserving quadriceps function in total knee arthroplasty (TKA). While the FTB reliably covers anteromedial knee innervation, the optimal location for the ACB remains controversial. This study aimed to compare the analgesic efficacy of a DSB using either a proximal (pACB) versus a distal ACB (dACB), testing the hypothesis that the dACB would provide superior analgesia via better coverage of posterior knee sensory pathways.

Methods: In this prospective, randomized trial, sixty-nine patients undergoing TKA under spinal anesthesia were allocated to receive either an FTB+pACB (Group 1) or an FTB+dACB (Group 2). The primary outcome was total morphine consumption in the first 24 hours. Secondary outcomes included pain scores at rest and on movement, time to first analgesic request, and functional recovery assessed by the EQ-5D scale.

Results: The primary outcome, 24-hour morphine consumption, was not significantly different between groups (median 3 mg (0–3) for both; P=0.839). Similarly, there were no statistically significant differences in pain scores at any time point, time to first analgesic request, or any domain of the EQ-5D scale. No significant quadriceps weakness was observed in either group.

Conclusions: Both DSB techniques provided excellent, motor-sparing analgesia with no significant difference in clinical outcomes. The choice between using a proximal or distal ACB may therefore be guided by practical considerations, such as procedural simplicity, rather than an expectation of superior efficacy.

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Presenting Author: Burapa Pajina
Submitting Author: Burapa Pajina

Senior Author: Prangmalee Leurcharusmee

IASP 2026 Global Year theme of Neuropathic Pain: No

• Burapa Pajina: MD. - Department of Anesthesiology, Nan Hospital, Nan, Thailand
• Prangmalee Leurcharusmee: MD, PhD - Department of Anesthesiology, Faculty of Medicine, Maharaj Nakorn Chiang Mai Hospital, Chiang Mai University, Chiang Mai, Thailand
• Worakamol Tiyaprasertkul: MD. - Department of Anesthesiology, Bangkok Hospital Chiang Mai, Chiang Mai, Thailand