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Published on: July 5, 2011
Surgically related upper cervical spine canal anatomy in children
N Jauregui1, T Lincoln, S Mubarak
1Department of Orthopedics, University of California at San Diego.
Insights
Pediatric upper spine MRI reveals accelerated C1 canal growth in infants. Neonatal space available for the cord (SAC) averages 12.4 mm, potentially below thresholds for spinal stenosis.
Area of Science:
- Pediatric Radiology
- Spinal Anatomy
- Neurosurgery
Background:
- Accurate C1 sagittal anatomy is crucial for pediatric spinal assessment.
- Understanding normal growth patterns aids in diagnosing spinal stenosis.
- Previous studies lack detailed pediatric C1 dimensional data.
Purpose of the Study:
- To precisely define the sagittal anatomy of the C1 region in children.
- To analyze growth patterns of the C1 bony canal, spinal cord, and surrounding spaces.
- To evaluate the applicability of Steel's rule of thirds in pediatric C1 anatomy.
Main Methods:
- Retrospective analysis of 121 pediatric upper spine MRI scans.
- Measurement of spinal cord, bony canal, space available for the cord (SAC), and atlanto-dens interval (ADI).
- Statistical analysis to determine growth trends and correlations.
Main Results:
- Significant accelerated growth observed in C1 canal, dens+ADI, and SAC during the first four years post-birth.
- Steel's rule of thirds demonstrated approximate validity throughout childhood.
- Neonates exhibit an average SAC diameter of 12.4 mm, below the 13 mm threshold for relative stenosis.
Conclusions:
- The C1 region undergoes rapid development in early childhood.
- Neonatal SAC dimensions may be misinterpreted as stenosis using standard adult criteria.
- Establishment of pediatric-specific normative data for C1 anatomy is essential.
Abstract:
MRI studies of the upper spines of 121 children were evaluated to precisely define the sagittal anatomy at C1 in the pediatric population. The diameters of the spinal cord, bony canal, space available for the cord (SAC), dens+atlanto-dens interval (ADI), and "free" space were measured. The results demonstrate an accelerated growth in the C1 canal, dens + ADI, and SAC during the first four years after birth. Steel's rule of thirds was shown to roughly hold true throughout childhood. Neonates have an average SAC diameter of 12.4 mm, a value less than the 13 mm dimension commonly used to define relative stenosis in children.
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