. Author manuscript; available in PMC: 2006 Nov 9.

Published in final edited form as: J Biomech Eng. 2005 Aug;127(4):692–699. doi: 10.1115/1.1933949

Table 2.

Absolute pose parameter bias±precision calculated from three synthetic fluoroscopic image sets corresponding to an in vivo experimental stair rise motion or randomly transformed bones in a fixed relative pose. Directions are with respect to the fluoroscopic coordinate system, where x (forward) and y (upward) are parallel to the image plane and z (outward) is perpendicular to the image plane.

Synthetic images	Pose parameters	Femur	Tibia/Fibula	Patella
Set 1	X translation (mm)	−0.031±0.27	0.081±0.42	0.16±0.48
Ray-Traced	Y translation (mm)	0.043±0.28	−0.49±0.21^a	0.66±0.71^a
Experimental	Z translation (mm)	−3.3±5.6^a	−11±5.2^a	−9.8±13^a
	X rotation (deg)	0.15±0.47	−0.18±1.3	−2.6±2.8^a
	Y rotation (deg)	0.99±0.72^a	−0.41±0.40^a	2.4±2.6^a
	Z rotation (deg)	−0.028±0.56	−0.065±0.22	−0.089±0.59
Set 2	X translation (mm)	0.17±0.28^a	0.031±0.37	0.41±0.30^a
Ray-Traced	Y translation (mm)	0.059±0.20	−0.42±0.36^a	−0.045±0.42
Random	Z translation (mm)	−6.7±5.7^a	−11±7.6^a	−13±10^a
	X rotation (deg)	−0.32±0.65^a	−0.043±0.87	−1.2±2.5^a
	Y rotation (deg)	0.56±0.60^a	−0.14±0.65	0.60±1.6^a
	Z rotation (deg)	−0.19±0.36^a	0.014±0.34	−0.042±0.14
Set 3	X translation (mm)	0.037±0.16	−0.037±0.20	0.078±0.11^a
Flat-Shaded	Y translation (mm)	−0.058±0.13^a	0.0093±0.18	−0.021±0.34
Random	Z translation (mm)	0.57±2.3	−0.46±3.1	0.22±4.2
	X rotation (deg)	−0.14±0.47	0.028±0.45	−0.39±1.3
	Y rotation (deg)	0.060±0.29	−0.074±0.29	0.25±1.7
	Z rotation (deg)	−0.046±0.093^a	−0.0012±0.14	0.0064±0.18

Bias is statistically different from zero (p<0.05) based on a Student’s t-test