Assessing the Use of Ultrasound to Quantify Spine Kinematics

This thesis described the use of ultrasound in measuring multiplanar in-vivo lumbar spine motion in various positions of flexion and axial rotation using two separate ultrasound-based methods and was compared to surface-based optoelectronic motion capture. 14 instances of outlier range of motion were detected with the sagittal imaging method and complex movement sequences were uncovered with the transverse imaging method. Two error metrics were described and evaluated: (1) repeatability, which described the likeness of repeated images and subsequent image analysis; (2) robustness, which described the tolerance of the ultrasound measurement system to systematically induced error. The sagittal imaging method was considered robust and repeatable however the transverse method was less repeatable, with error potentially resulting from soft tissue creep. This thesis demonstrated that it is possible to measure multiplanar intervertebral motion via US and may help identify risky movement sequences which may appear normal in a surface-based motion capture investigation.