Table 4

Head impact statistics in the 11 participants in the non-collar group and 11 participants in the collar group who underwent pre-season, post-season and off-season follow-up MRI testing

	Non-collar (n=11)				Collar (n=11)
	Range	Median	Mean	SD	Range	Median	Mean	SD
Total hits
>10g	161–1279	777	799	323	409–919	619	654	180
>20g	59–404	237	206	103	122–327	168	179	60.8
>50g	3–58	39	34.4	18.5	18–53	22	26.4	10.2
>100g	1–9	6	4.7	2.7	1–8	4	3.8	1.9
Total g-force
>10g	3638–21 992	15 620	15 307	6065	8493–19 124	12 318	12 767	3152
>20g	1852–14 335	8418	7585	3722	4567–11 901	5472	6488	2204
>50g	273.5–3981	3183	2545	1274	1266–3780	1965	1984	715.2
>100g	151.6–1090	742.8	610.0	345.7	120.2–1028.3	474.6	476.0	241.2
Average g-force
>10g	14.06–22.72	19.75	19.48	2.82	15.77–22.34	20.77	19.80	2.11
>20g	31.40–40.25	37.24	36.63	2.96	32.57–39.90	36.59	36.38	1.90
>50g	67.12–91.18	77.02	76.73	6.55	70.33–91.82	73.22	75.74	6.36
>100g	115.72–152.20	125.04	132.09	14.17	116.45–166.83	121.95	127.14	14.27