Methods for determining spine instability and for eliminating the impact of patient effort on stability determinations

摘要

The present disclosure describes a method for determining spinal instability, more particularly, a method for quantifying the type and extent of spinal instability in a standardized way. The disclosure also describes a method comprising measurement of the intervertebral rotation and intervertebral translation between a vertebrae pair using simple images, and from these measurements, determining if one or more vertebrae pair of the spine is unstable. Finally, the disclosure describes software that may be used to quantify the type and extent of spinal instability.

主权项

1. A method for calculating a spinal translation per degree of rotation (TPDR) comprising:
obtaining an x-ray film of a first and a second vertebrae in a first position; obtaining an x-ray film of a first and second vertebrae in a second position, wherein the degree of intervertebral rotation between the two positions is greater than 3 degrees; marking the position of at least one landmark on the first vertebra on the x-ray film of the first position; superimposing the two x-ray films and aligning the first vertebra and then determining the rotation and translation required to subsequently align the second vertebra; measuring the degree of vertebral rotation between the first and second vertebrae in the first and second positions; measuring the translation of the landmark on the first vertebra between the first and second positions while holding the second vertebra fixed; normalizing the intervertebral translation measurement based upon a vertebral dimension; dividing the normalized intervertebral translation by the intervertebral rotation to give a TPDR.