Lumbar spinal canal morphometry from computed tomography scans: reproducibility, results and clinical implications

Area of Science:

• Radiology
• Orthopedics
• Medical Imaging

Background:

• Accurate lumbar spine measurements are crucial for diagnosing spinal conditions.
• Computed tomography (CT) is a common imaging modality for spinal assessment.
• Understanding measurement reproducibility is essential for reliable clinical interpretation.

Purpose of the Study:

• To assess the reproducibility of lumbar spine measurements using CT scans.
• To identify factors affecting measurement accuracy.
• To evaluate the utility of a novel measurement (oblique sub-facet distance) in identifying spinal stenosis.

Main Methods:

• Reproducibility analysis of lumbar spine CT scans in 53 patients scanned multiple times.
• Identification of factors influencing measurement variability.
• Comparison of measurements from 142 patients with published data and 17 spinal stenosis patients.

Main Results:

• Overall measurement variation was low at 2.8%.
• Scan angle, oblique structure measurement, and soft-tissue boundaries reduced reproducibility.
• Spinal stenosis patients showed no significant difference in sagittal diameter or interpedicular distance compared to controls.
• The oblique sub-facet distance was significantly different in spinal stenosis patients.

Conclusions:

• Lumbar spine CT measurements are highly reproducible under optimal conditions.
• Specific factors can decrease measurement reliability.
• The oblique sub-facet distance is a promising new metric for detecting spinal stenosis.