NCT07191964

SSSI Efficacy With iACB and PC-LIA in TKA Pain Management

Assessment of Supra-Sartorial Subcutaneous Infiltration (SSSI) Efficacy When Combined With Intermittent Adductor Canal Block (iACB) and Posterior Capsule Local Infiltration Analgesia (PC-LIA) in Multimodal Pain Management for Total Knee Arthroplasty: A Randomized Controlled Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 90 (estimated)
• Sponsor: Taipei Medical University WanFang Hospital · Academic / Other
• Sex: All
• Age: 45 Years – 90 Years
• Healthy volunteers: Not accepted

Summary

This prospective, triple-blinded, sham-controlled randomized trial evaluates the additive effect of Supra-Sartorial Subcutaneous Infiltration (SSSI) combined with intermittent adductor canal block (iACB) and posterior capsule local infiltration analgesia (PC-LIA) for pain management in total knee arthroplasty (TKA). SSSI, a simpler alternative to targeted anterior femoral cutaneous nerve (AFCN) block, is tested in 90 adults (45-90 years) randomized into two arms: sham SSSI + active iACB + PC-LIA versus all active interventions. Primary outcome is pain scores on postoperative day 0; secondary outcomes include daily pain trajectory, opioid use, functional recovery, and complications over days 0-3.

Detailed description

This prospective, two-armed, triple-blinded, sham-controlled randomized controlled trial investigates the additive effect of Supra-Sartorial Subcutaneous Infiltration (SSSI) to intermittent adductor canal block (iACB) and posterior capsule local infiltration analgesia (PC-LIA) in multimodal pain management for total knee arthroplasty (TKA). SSSI is a peripheral nerve block technique the investigators devised as a simpler alternative to targeted anterior femoral cutaneous nerve (AFCN) block, which is technically more demanding and time-consuming. Based on the investigators' preliminary study (in publication) where SSSI combined with PC-LIA provided clinically meaningful analgesia in \~58% of patients, and drawing from previous studies on AFCN blocks, the trial compares: Arm 1 (all active SSSI + active iACB + active PC-LIA) versus Arm 2 (sham SSSI + active iACB + active PC-LIA). Adults (45-90 years) undergoing unilateral primary TKA (n=90, 45/arm) will be randomized 1:1, stratified by age, preoperative pain levels (in Numerical Rating Scale) and functional status (WOMAC Index or Knee Society Score). Interventions use 0.3% ropivacaine or saline shams, with SSSI and ACB catheterization performed in the post-anesthesia care unit by anesthesiologists and PC-LIA performed intraoperatively by surgeons. Primary outcome: Numerical Rating Scale pain scores at rest and during continuous passive motion at 9:00 PM on postoperative day (POD) 0, focusing on anteromedial knee pain. Secondary outcomes include daily pain scores, rescue ACB doses, additional opioid use, functional recovery (quadriceps strength, timed up and go \[TUG\] test), and complications over POD 0-3. With \~96% power for a 2-point NRS difference, this trial evaluates SSSI's role in enhancing motor-sparing analgesia.

Conditions

• Postoperative Pain Management in Total Knee Arthroplasty
• Peripheral Nerve Blocks

Interventions

Type	Name	Description
PROCEDURE	Supra-Sartorial Subcutaneous Infiltration (SSSI)	20 mL ropivacaine or saline infiltrated lateral-to-medial subcutaneously above sartorius at femoral triangle apex using inject-as-you-advance technique, avoiding hyperechoic nerves.
PROCEDURE	intermittent adductor canal block (iACB)	An adductor canal catheter is inserted proximal-to-distally over a distance of 6-10 cm at femoral triangle apex, with an initial bolus of 10 mL of 0.3% ropivacaine administered in PACU. The following doses start at 9:00 PM on the day of surgery and are repeated every 12 hours,
PROCEDURE	posterior capsule local infiltration analgesia (PC-LIA)	PC-LIA consists of two 10 mL injections of 0.3% ropivacaine delivered intraoperatively to the posteromedial and posterolateral aspects of the posterior capsule before cementation. The target injection plane is the potential space between the posterior capsule and the popliteal artery.

Timeline

• Start date: 2026-06-01
• Primary completion: 2027-06-01
• Completion: 2027-07-01
• First posted: 2025-09-25
• Last updated: 2026-04-01