Consistency of ASIS Line vs. Tuffier's Line for Lumbar Level Identification
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Lumbar Ultrasound & Palpation.
- Who it may be relevant to
- Registry conditions: Spinal Anesthesia Evaluation, Lumbar Vertebrae. Basic parameters: 18 years — 85 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- South Korea
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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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
Overview
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.
Interventions
- Diagnostic test Lumbar Ultrasound & Palpation
Identification of vertebral levels using Tuffier's line (palpation) and ASIS line, followed by ultrasound verification.
Primary outcome measures
- Consistency of Vertebral Level Identification (Standard Deviation) [Time frame: Day 1 (Immediately during the ultrasound examination)]
Secondary outcome measures (2)
- Difference in Mean Intersection Level [Time frame: Day 1]
- Rate of Identification within L4-L5 Interspace [Time frame: Day 1]
Eligibility criteria
Inclusion criteria
- 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
Exclusion criteria
- 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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
South Korea · 2 centers
- St. Vincent's Hospital — Suwon
- Kangbuk Samsung Hospital — Seoul
Identifiers
NCT: NCT07396961 · 2026-01-002