Table 1. Percent change in blood flow from baseline for incisional and posterior icing of the knee after TKA.

The sample median (range) is given to summarize the percentage change in blood flow from baseline as well as the difference in percentage change in blood flow from baseline between posterior and incisional areas. P-values vs. baseline for the separate incisional and posterior areas result from one-sample Wilcoxon rank sum tests, where the percentage change values were compared to a value of zero. P-values for comparisons of percentage blood flow from baseline result from paired Wilcoxon signed rank tests. One patient was missing value for 120-second blood flow in the incisional area.

TKA, total knee arthroplasty

	Incisional		Posterior		Posterior vs. Incisional
Time point	Percentage change in blood flow from baseline	P-value vs. baseline	Percentage change in blood flow from baseline	P-value vs. baseline	Difference in percentage change from baseline (incisional minus posterior)	P-value
0 seconds	-41.5 (-58.9, -15.7)	0.002	-39.2 (-52.6, -10.0)	0.002	-9.8 (-16.5, 0.0)	0.002
30 seconds	-43.5 (-57.6, -12.9)	0.002	-37.1 (-48.8, -9.0)	0.002	-7.4 (-12.0, 7.0)	0.014
60 seconds	-47.5 (-58.7, -14.4)	0.002	-37.8 (-53.9, -12.3)	0.002	-7.0 (-15.4, 4.8)	0.014
90 seconds	-48.5 (-61.8, -17.8)	0.002	-40.9 (-59.8, -10.0)	0.002	-8.0 (-17.1, 6.1)	0.020
120 seconds	-48.8 (-62.8, -18.2)	0.004	-39.9 (-61.0, -9.2)	0.002	-6.7 (-13.1, 3.5)	0.020