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Precision Measurements and Parametric Models of Vertebral Endplates
Published on: September 17, 2019
Quantifying cervical-spine curvature using Bézier splines
Kathleen D Klinich1, Sheila M Ebert, Matthew P Reed
1University of Michigan Transportation Research Institute, 2901 Baxter Rd., Ann Arbor, MI 48109, USA. kklinich@umich.edu
Journal of Biomechanical Engineering
|February 8, 2013
Summary
A new quantitative method uses two parameters, superior and inferior Bézier angles, to characterize cervical-spine curvature. This approach aids computational studies of spinal injury in motor-vehicle crashes.
Area of Science:
- Biomechanics
- Spinal Anatomy
- Injury Mechanics
Background:
- Cervical-spine curvature knowledge is crucial for computational injury studies in motor-vehicle crashes.
- Existing methods for assessing spinal curvature are often qualitative or parameter-intensive.
- A need exists for a quantitative, concise method to describe cervical-spine shape.
Purpose of the Study:
- To develop a quantitative method for characterizing cervical-spine curvature using a minimal set of parameters.
- To establish a classification scheme for different types and magnitudes of cervical-spine curvature.
Main Methods:
- Digitized posterior vertebral body and dens coordinates from 180 sagittal X-rays of subjects in automotive postures.
- Applied Bézier splines to digitized points to model spinal curvature.
- Parameterized spline control points using vector angle and length, defining curvature with superior and inferior Bézier angles.
Main Results:
- Cervical-spine curvature in automotive posture varies by gender and age, but not stature.
- Developed a classification system for curvature types (lordosis, S-shaped, kyphosis) and locations.
- Presented average superior and inferior Bézier angles for different genders, ages, and postures (flexion, neutral, extension).
Conclusions:
- Bézier splines provide a quantitative method for cervical-spine curvature characterization.
- The two-parameter system (superior and inferior Bézier angles) simplifies curvature analysis.
- This method is valuable for computational biomechanics and injury research.
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