Adverse EffectiSNB-LFNCT07366853
Feasibility and Safety of Sciatic Nerve Paraneural Sheath Block Using a Mid-Femoral Lateral Approach
A study testing Ultrasound-guided lateral mid-femoral sciatic nerve block and Ultrasound-guided popliteal sciatic nerve block in people with Adverse Effect and Feasibility Study, run by General Hospital of Ningxia Medical University at 1 site in China.
Trial 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… Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Adverse Effect, Feasibility Study, Safety and Effectiveness
- What is being tested?
- Ultrasound-guided lateral mid-femoral sciatic nerve block and Ultrasound-guided popliteal sciatic nerve block
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 200 participants
- Where
- 1 siteChina
- Study dates
- 1 Jan 2026to 1 Oct 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
Show all 12Show fewer
- 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.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site
General Hospital of Ningxia Medical University
Yinchuan, Ningxia, 750004
Yan Ren, MD, 18152372612, 3467592762@qq.com
About this study
Official title: Feasibility and Safety of Intraneural Sciatic Nerve Block Via Lateral Mid-femoral Approach: A Clinical Study
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.
Read the detailed description
In clinical practice, the popliteal approach to sciatic nerve paraneural sheath block is the most commonly used. Studies have found that compared with extraneural injection, ultrasound-guided sciatic nerve paraneural sheath block via the popliteal approach has a faster onset and provides longer postoperative sensory and motor blockade. Paraneural sheath block aims to achieve efficient, rapid, and precise nerve blockade using a low volume of local anesthetic. However, the popliteal approach requires knee flexion for performance, necessitating the patient to be in a prone or lateral decubitus position. For patients unable to flex the knee or those with positioning difficulties due to conditions such as lower limb fractures, this method is less applicable. For the above reasons, the popliteal sciatic nerve block has certain limitations.
The mid-femoral lateral approach demonstrates unique advantages: First, the patient can maintain a supine position throughout the procedure, significantly enhancing comfort and compliance. Second, the sciatic nerve is relatively superficial at this level, offering good ultrasonographic visualization and being distant from major blood vessels and nerves. This makes it applicable even in obese patients with thick subcutaneous fat and suboptimal ultrasound images, theoretically enhancing procedural safety. Therefore, it is considered an effective solution for patients with positioning restrictions, such as those with lower limb fractures and severe pain, holding high potential for clinical promotion and research significance.
Although the anatomical feasibility of this approach has been preliminarily confirmed, its practical feasibility and safety require validation through clinical studies. In particular, whether a successful "paraneural sheath block" can be consistently achieved at the mid-femoral lateral level, similar to the classic popliteal approach, remains to be explored. While some literature suggests its theoretical feasibility, there is a lack of prospective, systematic clinical research evidence to support its practical application feasibility (e.g., block efficacy, procedural difficulty, success rate) and safety (e.g., complication rates, incidence of nerve injury).
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. The goal is to provide a new sciatic nerve block option for clinical practice that offers greater patient comfort and more precise blockade, facilitating its use for specific patient populations and less experienced operators.
- Conditions
- Adverse Effect, Feasibility Study, Safety and Effectiveness
- Being tested
- Ultrasound-guided lateral mid-femoral sciatic nerve block, Ultrasound-guided popliteal sciatic nerve block
- Keywords
- Sciatic Nerve Block, Subparaneural Block, Lateral Mid-femoral Approach, Popliteal Approach, Ultrasound-guided, Feasibility, Safety
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ultrasound-guided lateral mid-femoral sciatic nerve blockProcedure or surgery
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
Ultrasound-guided popliteal sciatic nerve blockProcedure or surgery
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).
| Study group | Role | What they receive |
|---|---|---|
| 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. Receives: 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). Receives: Procedure: Ultrasound-guided popliteal sciatic nerve block |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: At 30 minutes after completion of the local anesthetic injection.
Secondary outcomes (13)
Block Success Rate
Proportion of patients achieving both complete sensory blockade (Grade III) and complete motor blockade (Grade III) in the sciatic nerve distribution at 30 minutes after local anesthetic injection.
Measured: At 30 minutes after block completion.
Sensory Block Onset Time
Time interval from the end of local anesthetic injection to the achievement of complete sensory blockade (Grade III).
Measured: From the end of injection until complete sensory block is achieved (assessed every 30 seconds), up to 30 minutes.
Duration of Sensory Block
Time interval from the onset of complete sensory blockade to the first complaint of pain in the surgical area (NRS > 0).
Measured: From block onset until first pain complaint, assessed up to 48 hours postoperatively.
Motor Block Onset Time
Time interval from the end of local anesthetic injection to the achievement of complete motor blockade (Grade III: inability to move the ankle).
Measured: From the end of injection until complete motor block is achieved (assessed every 30 seconds), up to 30 minutes.
Duration of Motor Block
Time interval from the onset of complete motor blockade to the recovery of normal ankle flexion and extension.
Measured: From block onset until full motor recovery, assessed up to 48 hours postoperatively.
Time to First Request for Rescue Analgesia
Time interval from the end of surgery to the patient's first activation of the patient-controlled intravenous analgesia (PCIA) pump or request for supplemental analgesia.
Measured: From end of surgery until first rescue request, assessed up to 24 hours postoperatively.
Total Consumption of Rescue Analgesics within 24 Hours
Total dose of rescue analgesics (e.g., parecoxib, ketorolac, morphine) administered within the first 24 postoperative hours.
Measured: Within 24 hours after surgery.
Postoperative Pain Intensity (NRS Scores)
Pain intensity assessed using the Numerical Rating Scale (NRS, 0-10) at rest and during movement at 4, 8, and 24 hours postoperatively.
Measured: At 4, 8, and 24 hours after surgery.
Incidence of Rebound Pain
Proportion of patients experiencing rebound pain, defined as an NRS score >7 within 48 hours after block resolution, not relieved by multiple PCIA boluses within 30 minutes.
Measured: Within 48 hours after block resolution.
Procedure-Related Times
- Ultrasound Scanning Time: Time from probe placement to clear identification of the target nerve.
- Total Needle Manipulation Time: Time from needle insertion to completion of drug injection.
Measured: During the block procedure.
Number of Needle Redirections
Total number of times the nerve stimulation needle is adjusted or redirected to achieve the final position.
Measured: During the block procedure.
Incidence of Complications
Proportion of patients experiencing block-related complications, including local anesthetic systemic toxicity, nerve injury (persistent neuropathy), hematoma, or infection.
Measured: From block procedure up to 1 week postoperatively.
Patient Satisfaction Score
Patient-reported satisfaction with the overall anesthesia and analgesia experience, assessed using a 5-point Likert scale (0=very dissatisfied, 5=very satisfied).
Measured: At 24 hours postoperatively.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Jan 2026
- Study start1 Jan 2026 (estimated)
- Primary completion1 Sep 2026 (estimated)
- Study completion1 Oct 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Adverse EffectStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- 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.
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Outcomes assessor
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- General Hospital of Ningxia Medical University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07366853
- Sponsor's protocol ID
- Yan Ren-2026-01
- Acronym
- iSNB-LF
- Status last verified
- Jan 2026
- First submitted
- 8 Jan 2026
- Last updated
- 26 Jan 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 26 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Feasibility and Safety of Intraneural Sciatic Nerve Block Via Lateral Mid-femoral Approach: A Clinical Study
- ClinicalTrials.gov ID
- NCT07366853
- Acronym / sponsor ID
- iSNB-LF / Yan Ren-2026-01
- Conditions
- Adverse Effect, Feasibility Study, Safety and Effectiveness
- Keywords
- Sciatic Nerve Block, Subparaneural Block, Lateral Mid-femoral Approach, Popliteal Approach, Ultrasound-guided, Feasibility, Safety
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 200 participants (estimated)
- Lead sponsor
- General Hospital of Ningxia Medical UniversityUniversity, hospital or other
- Study start
- 1 Jan 2026 (estimated)
- Primary completion
- 1 Sep 2026 (estimated)
- Study completion
- 1 Oct 2026 (estimated)
- First posted
- 26 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
In clinical practice, the popliteal approach to sciatic nerve paraneural sheath block is the most commonly used. Studies have found that compared with extraneural injection, ultrasound-guided sciatic nerve paraneural sheath block via the popliteal approach has a faster onset and provides longer postoperative sensory and motor blockade. Paraneural sheath block aims to achieve efficient, rapid, and precise nerve blockade using a low volume of local anesthetic. However, the popliteal approach requires knee flexion for performance, necessitating the patient to be in a prone or lateral decubitus position. For patients unable to flex the knee or those with positioning difficulties due to conditions such as lower limb fractures, this method is less applicable. For the above reasons, the popliteal sciatic nerve block has certain limitations.
The mid-femoral lateral approach demonstrates unique advantages: First, the patient can maintain a supine position throughout the procedure, significantly enhancing comfort and compliance. Second, the sciatic nerve is relatively superficial at this level, offering good ultrasonographic visualization and being distant from major blood vessels and nerves. This makes it applicable even in obese patients with thick subcutaneous fat and suboptimal ultrasound images, theoretically enhancing procedural safety. Therefore, it is considered an effective solution for patients with positioning restrictions, such as those with lower limb fractures and severe pain, holding high potential for clinical promotion and research significance.
Although the anatomical feasibility of this approach has been preliminarily confirmed, its practical feasibility and safety require validation through clinical studies. In particular, whether a successful "paraneural sheath block" can be consistently achieved at the mid-femoral lateral level, similar to the classic popliteal approach, remains to be explored. While some literature suggests its theoretical feasibility, there is a lack of prospective, systematic clinical research evidence to support its practical application feasibility (e.g., block efficacy, procedural difficulty, success rate) and safety (e.g., complication rates, incidence of nerve injury).
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. The goal is to provide a new sciatic nerve block option for clinical practice that offers greater patient comfort and more precise blockade, facilitating its use for specific patient populations and less experienced operators.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, outcomes assessor)
- Number of arms
- 2
- Model description
- 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.
| Arm | Type | Receives |
|---|---|---|
| Lateral Mid-femoral Approach Sciatic Nerve Block | Experimental | Procedure: Ultrasound-guided lateral mid-femoral sciatic nerve blockUltrasound-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. |
| Popliteal Approach Sciatic Nerve Block | Active comparator | Procedure: Ultrasound-guided popliteal sciatic nerve blockUltrasound-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). |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- 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.
Key exclusion criteria (12 listed)
- Contraindications to peripheral nerve block:
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Ultrasound-guided lateral mid-femoral sciatic nerve blockUltrasound-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 or surgery | Lateral Mid-femoral Approach Sciatic Nerve Block |
| Ultrasound-guided popliteal sciatic nerve blockUltrasound-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 or surgery | Popliteal Approach Sciatic Nerve Block |
Primary outcome
Rate of complete sensory blockade in the sciatic nerve distribution at 30 minutes after block completion
Time frame: At 30 minutes after completion of the local anesthetic injection.
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.
13 secondary outcomes
Block Success Rate
Time frame: At 30 minutes after block completion.
Sensory Block Onset Time
Time frame: From the end of injection until complete sensory block is achieved (assessed every 30 seconds), up to 30 minutes.
Duration of Sensory Block
Time frame: From block onset until first pain complaint, assessed up to 48 hours postoperatively.
Motor Block Onset Time
Time frame: From the end of injection until complete motor block is achieved (assessed every 30 seconds), up to 30 minutes.
Duration of Motor Block
Time frame: From block onset until full motor recovery, assessed up to 48 hours postoperatively.
Time to First Request for Rescue Analgesia
Time frame: From end of surgery until first rescue request, assessed up to 24 hours postoperatively.
Total Consumption of Rescue Analgesics within 24 Hours
Time frame: Within 24 hours after surgery.
Postoperative Pain Intensity (NRS Scores)
Time frame: At 4, 8, and 24 hours after surgery.
Incidence of Rebound Pain
Time frame: Within 48 hours after block resolution.
Procedure-Related Times
Time frame: During the block procedure.
Number of Needle Redirections
Time frame: During the block procedure.
Incidence of Complications
Time frame: From block procedure up to 1 week postoperatively.
Patient Satisfaction Score
Time frame: At 24 hours postoperatively.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 26 Jan 2026.
- Individual participant dataSharing planned: No
Related trials for Adverse Effect
RecruitingPhase 4
Propofol-Ketamine Versus Sevoflurane for Laryngeal Mask Anesthesia in Pediatric Cardiac Catheterization
Propofol, Ketamine
RecruitingObservational study
Late Subclinical Cardiovascular Disease in Testicular Cancer Survivors
Testicular Cancer, Survivorship
Not yet recruitingPhase 1
Safety and Tolerability of Single and Repeated Dose of IMM02-KORA in PD-associated Dyskinesia
Dyskinesia, Medication-induced, Dyskinesia, Drug-Induced
Active, not recruitingPhase 2
Infliximab for Treatment of Immune Checkpoint Inhibitor Colitis
Melanoma Stage III, Melanoma Stage IV
Active, not recruitingObservational study
M7824 Related Adverse Effects in Adults With Cancer
Neoplasms, Skin Neoplasms
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Ultrasound-guided lateral mid-femoral sciatic nerve block and Ultrasound-guided popliteal sciatic nerve block in people with Adverse Effect and Feasibility Study, run by General Hospital of Ningxia Medical University at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 26 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Gang Ma, MD，PhD (13709519220, magang2671@173.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Rate of complete sensory blockade in the sciatic nerve distribution at 30 minutes after block completion (time frame: At 30 minutes after completion of the local anesthetic injection.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Jan 2026.