Table 2.

Skeleton, lungs, and skin registration results. The results are separated in two columns: before registration, i.e.: after the initialization alone and after registration. For the bone, the used error metric is the joint localization error, while for the lungs, skin, and the whole skeleton, it is the point to surface distance

	Before registration	After registration
	Joint localization error (mm)
Right knee	14.29 ± 5.51	0.75 ± 0.29
Right ankle	18.70 ± 5.87	1.82 ± 1.01
Left knee	16.61 ± 4.80	0.77 ± 0.26
Left ankle	19.93 ± 5.15	1.69 ± 1.14
Right elbow	5.66 ± 2.11	1.31 ± 0.44
Right wrist	15.56 ± 4.49	1.27 ± 0.53
Left elbow	5.23 ± 2.96	1.23 ± 0.39
Left wrist	18.04 ± 6.47	1.21 ± 0.56
	Euclidean point to surface distance (mm)
Entire skeleton	3.68 ± 0.77	0.58 ± 0.03
Lungs	1.27 ± 0.26	0.47 ± 0.03
Skin	11.06 ± 8.49	0.75 ± 0.53