MRI Study on Spinal Canal Morphometry: An Indian Study

A large proportion of adults suffer from neck pain at some points of their life and show altered ranges of spinal canal morphometry in various studies. The differences in values are also seen due to genetic, hormonal and other factors too. Torg's ratio is a widely accepted measurement to eliminate such discrepancies. The measurement of Space Available for Cord (SAC) is also gaining importance as spinal stenosis is a contributor to neck pain.

(1) To examine the cervical spinal canal and spinal cord morphometric determinants in symptomatic sub-Himalayan North Bengal population and to compare the obtained data with other populations; (2) To determine whether Torg's ratio vary with gender or not; (3) To determine SAC values in symptomatic individuals.

Magnetic Resonance Imaging (MRI) based on midsagittal diameter of vertebral body, spinal canal, spinal cord and its Torg's ratio and SAC value of the lower cervical spine (C3-C7) from 71 symptomatic adults were recorded at the Radiology Department of North Bengal Medical College and Hospital, Bengal, India. Individuals with any evidence of trauma, infection, neoplasia or any congenital anomalies related to spinal canal and below 18 years of age were excluded from the study.

The average diameter for vertebral body was significantly larger in males. The average diameter for spinal canal, spinal cord and values of Torg's ratio and SAC has no significant gender difference. But the mean value of Torg's ratio is greater in females is due to smaller vertebral body size in females.

It is interpreted from our study that sagittal spinal canal diameter, Torg's ratio and SAC value did not show any significant gender difference. But sagittal vertebral body's diameter showed sexual dimorphism which influenced the mean value of Torg's ratio.