In Vivo Quantitative Ultrasound Image Analysis of Femoral Subchondral Bone in Knee Osteoarthritis

Table 3

Spearman’s rank correlations (𝑟) between ultrasound medial (MED), sulcus (SULC), and lateral (LAT) bone depth level intensities and intensity slopes and radiographic K-L grading or arthroscopic Noyes’ grading.

	K-L grading			Noyes’ grading
	𝑛	𝑟	95% CI	𝑛	𝑟	95% CI
MED level 1	31	0.457**	0.122–0.698	38	0.162	−0.166–0.458
MED level 2	31	0.419*	0.076–0.673	38	0.292	−0.031–0.559
MED level 3	31	0.373*	0.021–0.642	38	0.192	−0.136–0.482
MED level 4	31	0.405*	0.059–0.664	38	0.133	−0.195–0.434
MED level 5	31	0.232	−0.133–0.542	38	0.115	−0.213–0.419
MED level all	31	0.418*	0.075–0.673	38	0.167	−0.161–0.462
MED slope	31	0.360*	0.006–0.634	38	0.325*	0.006–0.584
SULC level 1	30	0.244	−0.128–0.555	38	−0.022	−0.339–0.300
SULC level 2	30	0.541**	0.224–0.754	38	0.372*	0.059–0.618
SULC level 3	30	0.390*	0.035–0.658	38	0.462**	0.167–0.681
SULC level 4	30	0.202	−0.171–0.524	38	0.242	−0.084–0.521
SULC level 5	30	0.201	−0.172–0.523	38	0.282	−0.041–0.552
SULC level all	30	0.394*	0.039–0.661	38	0.358*	0.043–0.608
SULC slope	30	0.482**	0.147–0.718	38	0.427**	0.124–0.657
LAT level 1	31	0.109	−0.255–0.446	38	0.029	−0.293–0.345
LAT level 2	31	0.117	−0.248–0.452	38	−0.038	−0.353–0.285
LAT level 3	31	−0.179	−0.501–0.187	38	−0.091	−0.399–0.236
LAT level 4	31	−0.080	−0.422–0.282	38	0.063	−0.262–0.375
LAT level 5	31	−0.009	−0.362–0.347	38	0.093	−0.234–0.401
LAT level all	31	0.062	−0299–0.407	38	0.008	−0.312–0.327
LAT slope	31	−0.049	−0.396–0.311	38	−0.095	−0.402–0.232

^∗𝑃<0.05.
^∗∗𝑃<0.01.