AzTrials
AzTrials

Spinal Anesthesia EvaluationNCT07396961

Consistency of ASIS Line vs. Tuffier's Line for Lumbar Level Identification

An observational study of Spinal Anesthesia Evaluation and Lumbar Vertebrae, run by Kangbuk Samsung Hospital at 2 sites in South Korea.

Not yet recruiting

Opening soon. The study is approved but enrolment has not started yet. Sites may already take enquiries.

Sites and contacts
Official record
Search all trials

Trial summary

Tuffier's line is commonly used as a landmark for estimating lumbar vertebral levels during spinal anesthesia. However, its accuracy can vary depending on factors such as age, sex, BMI, and posture. Read more about this study

Who is it for?
Ages 18 to 85 years
What is being tested?
Lumbar Ultrasound & Palpation
How many people
140 participants
Where
2 sitesSouth Korea
Study dates
20 Feb 2026to 20 Feb 2028
Phase
Observational
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 85 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Patients visiting the study centers (Kangbuk Samsung Hospital or St. Vincent's Hospital) who are scheduled for spinal anesthesia or lumbar ultrasound.

Who may be able to join

  • Adults aged 18 to 85 years
  • Patients scheduled for spinal anesthesia or lumbar ultrasound
  • Participants who voluntarily agreed to participate and provided written informed consent

Who cannot join

  • History of spinal surgery or spinal deformity
  • Infection or wounds at the puncture site
  • Inability to maintain the lateral decubitus position
  • Congenital lumbosacral transitional vertebrae (e.g., sacralized L5 or lumbarized S1)
  • Any other condition deemed unsuitable for the study by the investigator

Trial locations and contacts

2 sites in 1 country. Contact the study team or a site near you to ask about taking part.

Sung Hyun Lee, MD, PhD contact

+82-2-2001-1666

hoho4321.lee@samsung.com

South Korea2 sites
  • Kangbuk Samsung Hospital

    Seoul, 03181

    Sung Hyun Ldd, MD, PhD, hoho4321.lee@samsung.com

  • St. Vincent's Hospital

    Suwon, North Carolina, 27516

    Yoo Jung Park, + 82-31-249-8446, genial7@naver.com

    SUNG HYUN LEE, +82-1-2001-2323, 4321hoho@naver.com

Other trials in South Korea

About this study

Official title: Evaluation of the Consistency of the ASIS Line for Lumbar Level Identification in the Lateral Decubitus Position: Comparison With the Tuffier's Line

Tuffier's line is commonly used as a landmark for estimating lumbar vertebral levels during spinal anesthesia. However, its accuracy can vary depending on factors such as age, sex, BMI, and posture. This study evaluates the consistency of an alternative landmark, the "ASIS line" (a line connecting both Anterior Superior Iliac Spines), for identifying lumbar levels in the lateral decubitus position. Researchers will mark both the ASIS line and Tuffier's line on participants and use ultrasound to verify the exact vertebral level where each line crosses the spine. The goal is to determine if the ASIS line provides a more consistent and reliable estimation of lumbar levels compared to Tuffier's line.

Being tested
Lumbar Ultrasound & Palpation
Keywords
vertebral level, Ultrasound, Tuffier's line, ASIS, Lateral decubitus position

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Lumbar Ultrasound & PalpationDiagnostic test

    Identification of vertebral levels using Tuffier's line (palpation) and ASIS line, followed by ultrasound verification.

Study groups in NCT07396961
Study groupRoleWhat they receive
Study CohortAdult patients (aged 18-85) scheduled for spinal anesthesia or lumbar ultrasound
Receives: Diagnostic Test: Lumbar Ultrasound & Palpation

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Consistency of Vertebral Level Identification (Standard Deviation)

    The specific vertebral level where the ASIS line and Tuffier's line intersect the spine will be identified using ultrasound. The lumbar spine (from L2 upper to S1 upper) is divided into segments (e.g., L2=2, L3=3, L4=4, L5=5, S1=6). The consistency of each method is evaluated by calculating and comparing the standard deviation (SD) of the identified vertebral levels.

    Measured: Day 1 (Immediately during the ultrasound examination)

Secondary outcomes (2)
  1. Difference in Mean Intersection Level

    Comparison of the mean vertebral levels identified by the ASIS line versus Tuffier's line to determine if there is a significant difference in the average level indicated.

    Measured: Day 1

  2. Rate of Identification within L4-L5 Interspace

    The percentage of cases where the identified line falls within the target L4-L5 interspace (or within ±1 interspace range).

    Measured: Day 1

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted9 Feb 2026
  2. Study start20 Feb 2026 (estimated)
  3. Primary completion20 Feb 2027 (estimated)
  4. Study completion20 Feb 2028 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Cohort
Time perspective
Prospective
Enrolment
140 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07396961
Sponsor's protocol ID
2026-01-002
Status last verified
Jan 2026
First submitted
30 Jan 2026
Last updated
9 Feb 2026
Results posted
No
Data monitoring committee
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

An observational study of Spinal Anesthesia Evaluation and Lumbar Vertebrae, run by Kangbuk Samsung Hospital at 2 sites in South Korea.

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 3 inclusion and 5 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 9 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in South Korea. 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 Sung Hyun Lee, MD, PhD (+82-2-2001-1666, hoho4321.lee@samsung.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Consistency of Vertebral Level Identification (Standard Deviation) (time frame: Day 1 (Immediately during the ultrasound examination)). 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 9 Feb 2026.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in