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.
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
- Conditions the study is for
- Spinal Anesthesia Evaluation, Lumbar Vertebrae
- 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.
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
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.
- Conditions
- Spinal Anesthesia Evaluation, Lumbar Vertebrae
- 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 group | Role | What they receive |
|---|---|---|
| Study Cohort | Adult 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.
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)
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
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.
- First posted9 Feb 2026
- Study start20 Feb 2026 (estimated)
- Primary completion20 Feb 2027 (estimated)
- Study completion20 Feb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Spinal Anesthesia EvaluationStudies 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 140 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Kangbuk Samsung Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sung Hyun Lee, Kangbuk Samsung Hospital
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
Study at a glance
From the registry record, last updated by the sponsor on 9 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- 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
- ClinicalTrials.gov ID
- NCT07396961
- Acronym / sponsor ID
- 2026-01-002
- Conditions
- Spinal Anesthesia Evaluation, Lumbar Vertebrae
- Keywords
- vertebral level, Ultrasound, Tuffier's line, ASIS, Lateral decubitus position
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 140 participants (estimated)
- Lead sponsor
- Kangbuk Samsung HospitalUniversity, hospital or other
- Study start
- 20 Feb 2026 (estimated)
- Primary completion
- 20 Feb 2027 (estimated)
- Study completion
- 20 Feb 2028 (estimated)
- First posted
- 9 Feb 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.
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.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Study Cohort | – | Diagnostic Test: Lumbar Ultrasound & PalpationAdult patients (aged 18-85) scheduled for spinal anesthesia or lumbar ultrasound |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- 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.
Key inclusion criteria (3 listed)
- 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
Key exclusion criteria (5 listed)
- 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
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 |
|---|---|---|
| Lumbar Ultrasound & PalpationIdentification of vertebral levels using Tuffier's line (palpation) and ASIS line, followed by ultrasound verification. | Diagnostic test | Study Cohort |
Primary outcome
Consistency of Vertebral Level Identification (Standard Deviation)
Time frame: Day 1 (Immediately during the ultrasound examination)
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.
2 secondary outcomes
Difference in Mean Intersection Level
Time frame: Day 1
Rate of Identification within L4-L5 Interspace
Time frame: Day 1
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 9 Feb 2026.
- Individual participant dataSharing planned: No
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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.
2 sites in 1 country: see every site and its status.
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.