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Geometry of the intervertebral volume and vertebral endplates of the human spine.

van der Houwen EB, Baron P, Veldhuizen AG, Burgerhof JG, van Ooijen PM, Verkerke GJ - Ann Biomed Eng (2009)

Bottom Line: Ten adjacent points on both sides of the vertebrae (S1-superior to T12-inferior) and sagittal and transverse diameters were measured to describe the shape of the caudal and cranial vertebral planes of the vertebrae.It was found that the largest endplate depth is located in the middle or posterior regions of the vertebra, that there is a linear relationship between all inferior endplate depths and the endplate location (p < 0.0001) within the spinal column, and that the superior endplate depth increases with age by about 0.01 mm per year (p < 0.02).The results allow for improvement of the fit of intervertebral disc-prostheses to the vertebrae and optimized force transmission through the vertebral column.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, University Medical Center Groningen, University of Groningen, A. Deusinglaan 1, 9713AV, Groningen, The Netherlands. vdhouwen@gmail.com

ABSTRACT
Replacement of a degenerated vertebral disc with an artificial intervertebral disc (AID) is currently possible, but poses problems, mainly in the force distribution through the vertebral column. Data on the intervertebral disc space geometry will provide a better fit of the prosthesis to the vertebrae, but current literature on vertebral disc geometry is very scarce or not suitable. In this study, existing CT-scans of 77 patients were analyzed to measure the intervertebral disc and vertebral endplate geometry of the lumbar spine. Ten adjacent points on both sides of the vertebrae (S1-superior to T12-inferior) and sagittal and transverse diameters were measured to describe the shape of the caudal and cranial vertebral planes of the vertebrae. It was found that the largest endplate depth is located in the middle or posterior regions of the vertebra, that there is a linear relationship between all inferior endplate depths and the endplate location (p < 0.0001) within the spinal column, and that the superior endplate depth increases with age by about 0.01 mm per year (p < 0.02). The wedge angle increases from T12-L1 to L5-S1. The results allow for improvement of the fit of intervertebral disc-prostheses to the vertebrae and optimized force transmission through the vertebral column.

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Related in: MedlinePlus

Nomenclature and planes of orientation
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Fig1: Nomenclature and planes of orientation

Mentions: The CT-scans were visualized and analyzed using Vitrea2 software (Vital Images Inc., Minnetonka, Minnesota, US). Average intensity projections with a thickness of 3.13 mm were reconstructed. A total of 10 coordinates were measured on each endplate. Figure 1 shows the coordinates of the superior endplate; five of these are in the sagittal (side) plane and five are in the frontal plane. The arbitrarily chosen frontal plane intersects point 3 of the sagittal plane. The coordinates 1, 5, 6, and 10 are the intersections of the tangent line with the vertebral body rims. The coordinates 3 and 8 both represent the middle of the endplate but were measured in the different viewing planes so they will not coincide exactly.Figure 1


Geometry of the intervertebral volume and vertebral endplates of the human spine.

van der Houwen EB, Baron P, Veldhuizen AG, Burgerhof JG, van Ooijen PM, Verkerke GJ - Ann Biomed Eng (2009)

Nomenclature and planes of orientation
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2803258&req=5

Fig1: Nomenclature and planes of orientation
Mentions: The CT-scans were visualized and analyzed using Vitrea2 software (Vital Images Inc., Minnetonka, Minnesota, US). Average intensity projections with a thickness of 3.13 mm were reconstructed. A total of 10 coordinates were measured on each endplate. Figure 1 shows the coordinates of the superior endplate; five of these are in the sagittal (side) plane and five are in the frontal plane. The arbitrarily chosen frontal plane intersects point 3 of the sagittal plane. The coordinates 1, 5, 6, and 10 are the intersections of the tangent line with the vertebral body rims. The coordinates 3 and 8 both represent the middle of the endplate but were measured in the different viewing planes so they will not coincide exactly.Figure 1

Bottom Line: Ten adjacent points on both sides of the vertebrae (S1-superior to T12-inferior) and sagittal and transverse diameters were measured to describe the shape of the caudal and cranial vertebral planes of the vertebrae.It was found that the largest endplate depth is located in the middle or posterior regions of the vertebra, that there is a linear relationship between all inferior endplate depths and the endplate location (p < 0.0001) within the spinal column, and that the superior endplate depth increases with age by about 0.01 mm per year (p < 0.02).The results allow for improvement of the fit of intervertebral disc-prostheses to the vertebrae and optimized force transmission through the vertebral column.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, University Medical Center Groningen, University of Groningen, A. Deusinglaan 1, 9713AV, Groningen, The Netherlands. vdhouwen@gmail.com

ABSTRACT
Replacement of a degenerated vertebral disc with an artificial intervertebral disc (AID) is currently possible, but poses problems, mainly in the force distribution through the vertebral column. Data on the intervertebral disc space geometry will provide a better fit of the prosthesis to the vertebrae, but current literature on vertebral disc geometry is very scarce or not suitable. In this study, existing CT-scans of 77 patients were analyzed to measure the intervertebral disc and vertebral endplate geometry of the lumbar spine. Ten adjacent points on both sides of the vertebrae (S1-superior to T12-inferior) and sagittal and transverse diameters were measured to describe the shape of the caudal and cranial vertebral planes of the vertebrae. It was found that the largest endplate depth is located in the middle or posterior regions of the vertebra, that there is a linear relationship between all inferior endplate depths and the endplate location (p < 0.0001) within the spinal column, and that the superior endplate depth increases with age by about 0.01 mm per year (p < 0.02). The wedge angle increases from T12-L1 to L5-S1. The results allow for improvement of the fit of intervertebral disc-prostheses to the vertebrae and optimized force transmission through the vertebral column.

Show MeSH
Related in: MedlinePlus