Table 3.

Inter-technique comparison: maximal synovial thickness

Reader	Maximal synovial thickness (mm)	DIR	CE-MRI	p value	rs	p value
Reader 1	Per location
	Suprapatellar recesses	1.0 (0.0–1.4)	1.0 (0.0–1.3)	.08a	0.95	< .001*
	Patellofemoral	1.0 (1.0–1.6)	1.0 (1.0–1.4)	.09a	0.95	< .001*
	Infrapatellar fat pad	0.0 (0.0–1.3)	0.0 (0.0–1.0)	.62a	0.97	< .001*
	Cruciate Ligaments	1.8 (1.0–2.6)	1.6 (1.0–2.4)	.50a	0.89	< .001*
	Medial posterior condyle	0.0 (0.0–1.0)	0.0 (0.0–1.3)	.68a	0.85	< .001*
	Lateral posterior condyle	0.0 (0.0–1.0)	0.0 (0.0–1.0)	.60a	0.99	< .001*
	Per child	1.9 (1.0–2.8)	1.9 (1.0–2.4)	.46a	0.96	< .001*
	Total measurements (n = 156)	1.0 (0.0–1.6)	1.0 (0.0–1.4)	.44a	0.93	< .001*
Reader 2	Per location
	Suprapatellar recesses	1.0 (0.0–1.6)	1.2 (0.0–1.7)	.67a	0.88	< .001*
	Patellofemoral	1.2 (1.0–1.4)	1.3 (0.8–1.7)	.18a	0.84	< .001*
	Infrapatellar fat pad	0.0 (0.0–1.0)	0.0 (0.0–1.2)	.82a	0.93	< .001*
	Cruciate Ligaments	1.5 (0.0–2.1)	1.3 (1.0–2.5)	.18a	0.73	< .001*
	Medial posterior condyle	0.0 (0.0–1.3)	0.0 (0.0–1.2)	.47a	0.85	< .001*
	Lateral posterior condyle	0.0 (0.0–1.0)	0.0 (0.0–1.0)	.27a	0.99	< .001*
	Per child	1.6 (1.3–2.4)	1.6 (1.0–2.6)	.53a	0.90	< .001*
	Total measurements (n = 156)	1.0 (0.0–1.4)	1.0 (0.0–1.6)	.28a	0.87	< .001*
Reader 3	Per location
	Suprapatellar recesses	1.3 (0.0–1.6)	1.3 (0.0–1.8)	.18a	0.83	< .001*
	Patellofemoral	1.5 (1.3–1.8)	1.4 (0.8–1.7)	.07a	0.68	< .001*
	Infrapatellar fat pad	0.0 (0.0–1.7)	0.0 (0.0–1.7)	.36a	0.96	< .001*
	Cruciate Ligaments	1.7 (1.2–2.2)	1.8 (1.1–2.2)	.78a	0.84	< .001*
	Medial posterior condyle	0.0 (0.0–1.5)	0.0 (0.0–1.6)	.07a	0.98	< .001*
	Lateral posterior condyle	0.0 (0.0–1.0)	0.0 (0.0–1.1)	.44a	0.80	< .001*
	Per child	1.8 (1.5–2.5)	1.9 (1.3–2.3)	.68a	0.94	< .001*
	Total measurements (n = 156)	1.2 (0.0–1.7)	1.0 (0.0–1.8)	.36a	0.89	< .001*
Reader 4	Per location
	Suprapatellar recesses	1.2 (0.0–1.6)	1.3 (0.0–1.7)	.16a	0.90	< .001*
	Patellofemoral	1.4 (1.1–2.0)	1.5 (1.0–1.9)	.64a	0.79	< .001*
	Infrapatellar fat pad	0.0 (0.0–1.6)	0.0 (0.0–1.5)	.69a	0.98	< .001*
	Cruciate Ligaments	1.5 (1.0–2.2)	1.6 (1.2–2.5)	.06a	0.95	< .001*
	Medial posterior condyle	0.0 (0.0–1.1)	0.0 (0.0–1.3)	.67a	0.99	< .001*
	Lateral posterior condyle	0.0 (0.0–1.1)	0.0 (0.0–1.2)	.11a	0.99	< .001*
	Per child	1.8 (1.3–2.4)	1.8 (1.3–2.6)	.86a	0.85	< .001*
	Total measurements (n = 156)	1.0 (0.0–1.8)	1.1 (0.0–1.7)	.07a	0.96	< .001*

Data are displayed as median (interquartile range). Data are based on 26 measurements, unless otherwise stated

r_s, Spearman’s rank-order correlation; DIR, double inversion recovery; CE, contrast-enhanced

*p value < .05

^aWilcoxon signed-rank test