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PubMed · 9306529

A noninvasive, three-dimensional spinal motion analysis method.

T H Lim·J C Eck·H S An·L M McGrady·G F Harris·V M Haughton
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Abstract

STUDY DESIGN: A three-dimensional, noninvasive motion analysis method was developed by monitoring the orientation of the principal axes of each vertebra. OBJECTIVES: To develop a method of performing three-dimensional, noninvasive motion analysis of the spine using computed tomography data. SUMMARY OF BACKGROUND DATA: The concept of using principal axes of the moment of inertia tensor to measure the orientation and position of a rigid body has been applied to the wrist and subtalar joints, but has not yet been applied to the spine. METHODS: Scans were taken of two isolated vertebrae in various known positions. Centroids, area, moments, and product of inertia of each scan were determined using a commercial program. Custom software combined data using the parallel axis theorem to give three-dimensional data for each vertebra. Changes in the centroid and principal axes were used to calculate translation and rotation, respectively. RESULTS: The system accuracy was within 1.0 degree in rotation and 1.0 mm in translation. Some errors occurred in minor motions when a smaller number of scans were used. System resolution was 0.43 mm. CONCLUSIONS: A system has been developed capable of calculating three-dimensional spinal motion based on measurements of a series of computed tomography images. The system has an accuracy similar to that of current motion analysis methods, but future studies will be necessary to apply this system in vivo.

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CadaverCervical VertebraeHumansImage Processing, Computer-AssistedRange of Motion, ArticularTomography, X-Ray ComputedJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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T H Lim, J C Eck, H S An, L M McGrady, G F Harris, V M Haughton. 1997-09-01. A noninvasive, three-dimensional spinal motion analysis method.. https://doi.org/10.1097/00007632-199709010-00011

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