Neonatal lumbar puncture: are clinical landmarks accurate?

Area of Science:

• Neonatal medicine
• Pediatric anesthesiology
• Clinical anatomy

Background:

• The intercristal line (ICL), identified by the iliac crest, is clinically used to determine lumbar puncture (LP) entry points in neonates.
• Standard practice involves needle insertion at the L3/4 or L4/5 intervertebral space.

Purpose of the Study:

• To investigate the vertebral level indicated by manual palpation of the ICL.
• To assess the reliability of manual palpation in identifying specific intervertebral spaces for neonatal LP.

Main Methods:

• Thirty term neonates were studied.
• Pediatricians manually identified and marked the ICL and the intervertebral space above in neonates positioned laterally.
• Ultrasonography confirmed anatomical positions and the conus medullaris termination.

Main Results:

• The ICL was identified across vertebral levels L2/3 to L5/S1.
• In 83% of neonates, the ICL was at the intended L3/4 to L4/5 level.
• The identified LP site was higher than intended in 36% of cases, with the conus medullaris terminating at L2 or lower in 36%.

Conclusions:

• Significant variations exist in ICL and potential LP site locations.
• Using the ICL for guiding neonatal LP appears inaccurate.
• This inaccuracy poses a risk of potential spinal cord damage.