Table 2.

The effect of registration on the 90%-CRLB_σ of all voxels in the eight ROIs combined and of each ROI separately

ROI	Patients (n = 11)		Controls (n = 10)
	Median differencea	P valueb	Median difference	P value
All voxels in the eight ROIs	55.8	0.003	112.9	0.005
Femoral cartilage in the selected slice in the lateral compartment: Initial MRI	71.6	0.004	1,561.6	0.005
Femoral cartilage in the selected slice in the medial compartment: Initial MRI	223.2	0.003	210.9	0.005
Lateral femoral cartilage on second MRI	73.8	0.003	677.6	0.005
Medial femoral cartilage on second MRI	104.8	0.003	72.8	0.009
Tibial cartilage in the selected slice in the lateral compartment: Initial MRI	-5.7	0.374	-63.1	0.647
Tibial cartilage in the selected slice in the medial compartment: Initial MRI	-7.4	0.350	-5.1	0.508
Lateral tibial cartilage on second MRI	3.0	0.424	-45.0	0.959
Medial tibial cartilage on second MRI	-15.4	0.286	148.6	0.037

^aDifferences in the median of the 90%-CRLB_σ for all subjects between no registration and automated registration

^bP values of the Wilcoxon signed rank test