Feasibility and Safety of Sciatic Nerve Paraneural Sheath Block Using a Mid-Femoral Lateral Approach

NCT07366853 | Not Yet Recruiting DMC

• 1 other identifier: Yan Ren-2026-01
• Study Type: interventional
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

This study is designed as a randomized controlled trial aiming to evaluate the feasibility and safety of ultrasound-guided mid-femoral lateral approach sciatic nerve paraneural sheath block, in order to provide a new sciatic nerve block approach for clinical practice that offers greater patient comfort and higher precision, thereby facilitating its use for specific patient populations and less experienced operators.

Conditions

Adverse Effect; Feasibility Study; Safety and Effectiveness

Keywords

Sciatic Nerve Block; Subparaneural Block; Lateral Mid-femoral Approach; Popliteal Approach; Ultrasound-guided; Feasibility; Safety

Outcome Measures

Primary Outcomes (1)

• Rate of complete sensory blockade in the sciatic nerve distribution at 30 minutes after block completion

  The proportion of patients achieving complete sensory blockade (Grade III: numbness, no sensation to pinprick) in the tibial and common peroneal nerve distributions at 30 minutes following the administration of the local anesthetic. Sensory blockade will be assessed using von Frey filaments and compared to the contralateral limb.

  At 30 minutes after completion of the local anesthetic injection.

Secondary Outcomes (13)

• Block Success Rate

  At 30 minutes after block completion.

• Sensory Block Onset Time

  From the end of injection until complete sensory block is achieved (assessed every 30 seconds), up to 30 minutes.

• Duration of Sensory Block

  From block onset until first pain complaint, assessed up to 48 hours postoperatively.

• Motor Block Onset Time

  From the end of injection until complete motor block is achieved (assessed every 30 seconds), up to 30 minutes.

• Duration of Motor Block

  From block onset until full motor recovery, assessed up to 48 hours postoperatively.

Study Arms (2)

Lateral Mid-femoral Approach Sciatic Nerve Block

EXPERIMENTAL

Ultrasound-guided sciatic nerve subparaneural sheath block via the lateral mid-femoral approach. Under combined ultrasound and nerve stimulator guidance, a single injection of 20 mL of 0.5% ropivacaine hydrochloride will be administered into the paraneural sheath at the mid-femoral level.

Procedure: Ultrasound-guided lateral mid-femoral sciatic nerve block

Popliteal Approach Sciatic Nerve Block

ACTIVE COMPARATOR

Ultrasound-guided sciatic nerve subparaneural sheath block via the conventional popliteal approach. Under combined ultrasound and nerve stimulator guidance, a single injection of 20 mL of 0.5% ropivacaine hydrochloride will be administered into the paraneural sheath at the popliteal fossa (prior to nerve bifurcation).

Procedure: Ultrasound-guided popliteal sciatic nerve block

Interventions

Ultrasound-guided lateral mid-femoral sciatic nerve block PROCEDURE

Ultrasound-guided sciatic nerve subparaneural sheath block via the lateral mid-femoral approach. Under combined ultrasound and nerve stimulator guidance, a single injection of 20 mL of 0.5% ropivacaine hydrochloride will be administered into the paraneural sheath at the mid-femoral level

Lateral Mid-femoral Approach Sciatic Nerve Block

Ultrasound-guided popliteal sciatic nerve block PROCEDURE

Ultrasound-guided sciatic nerve subparaneural sheath block via the conventional popliteal approach. Under combined ultrasound and nerve stimulator guidance, a single injection of 20 mL of 0.5% ropivacaine hydrochloride will be administered into the paraneural sheath at the popliteal fossa (prior to nerve bifurcation).

Popliteal Approach Sciatic Nerve Block

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients scheduled for elective unilateral surgery below the knee (e.g., internal fixation for ankle, metatarsal, or calcaneal fractures; hallux valgus correction; flatfoot reconstruction).
• American Society of Anesthesiologists (ASA) physical status class I or II.
• Aged 18 to 65 years.
• Ability to understand the study procedure and provide written informed consent.

You may not qualify if:

• Contraindications to peripheral nerve block:
• Known allergy or history of toxicity to local anesthetics.
• Pre-existing neuropathy in the operative limb.
• Severe coagulopathy.
• Infection at the intended needle puncture site.
• Systemic infection.
• Requirement for simultaneous surgery at a site other than the unilateral lower limb below the knee.
• Previous surgery or significant scarring in the area of the planned needle insertion for the sciatic nerve block.
• Body mass index (BMI) \> 35 kg/m².
• Patients receiving chronic pain therapy or with a history of opioid abuse.
• Inability to communicate or cooperate with the study assessments (e.g., due to cognitive impairment, language barrier, or psychiatric disorder).
• Pregnancy or lactation.

Sponsors & Collaborators

• General Hospital of Ningxia Medical University: lead

Study Sites (1)

General Hospital of Ningxia Medical University

Yinchuan, Ningxia, 750004, China

Location

Central Study Contacts

Gang Ma, MD，PhD

CONTACT

13709519220; magang2671@173.com

Yan Ren, MD

CONTACT

18152372612; 3467592762@qq.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This is a prospective, parallel-group, randomized, controlled, double-blinded (participant and outcome assessor), exploratory feasibility trial. It compares ultrasound-guided subparaneural sciatic nerve block via a novel lateral mid-femoral approach (experimental) with the conventional popliteal approach (active control) in patients undergoing below-knee surgery. The primary aim is to assess the feasibility and safety of the new approach. Participants are randomized 1:1. Blinding is achieved through general anesthesia (participant) and use of an independent, blinded assessor for outcome evaluation.

Study Record Dates

• First Submitted: January 8, 2026
• First Posted: January 26, 2026
• Study Start: January 1, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): October 1, 2026
• Last Updated: January 26, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)