Table 1. Comparison between a medial meniscus root tear and lateral meniscus root tear.

	Medial meniscus root tear	Lateral meniscus root tear	p-value
Number of patients in study group	22	20
Mean age of patients (years)	52 (range, 29 ~ 71)	30 (range, 14 ~ 62)	p<0.0001
Meniscal extrusion
Number of meniscal extrusion case	18	1	p<0.0001
Mean extent of meniscal extrusion (mm)	4.2 (range, 0.6 ~ 7.8)	0.9 (range, -1.9 ~ 3.4)
Number of ACL tear case	3	19	p<0.0001
Number of patients who had trauma	5	19	p<0.0001
Kellgren-Lawrence grade
Grade 0~1	3	14	p<0.0001
Grade 2	4	4
Grade 3	14	2
Grade 4	1	0