2.

股骨颈骨折内固定术后发生股骨头坏死的单因素卡方检验

χ² test for necrosis of femoral head after internal fixation

Parameter	Total(n=113)	Necrosis(n=18)	Non-necrosis(n=95)	OR	P value	95%CI
BMI, body mass index; ASA, American Society of Anesthesiology; CCS, cannulated compression screw; DHS, dynamic hip screw. a, ASA Ⅲ was set as the standard; b, basal was set as the standard; c, Pauwels Ⅲ was set as the standard; d, reduction quality C was set as the standard.
Gender				1.29	0.62	0.46, 3.64
Male	63	11	52
Female	50	7	43
Age/years				0.91	0.86	0.33, 2.57
< 40	46	7	39
40-60	67	11	56
BMI/(kg/m2)				0.69	0.53	0.22, 2.18
≤25	88	13	75
>25	25	5	20
ASA gradea					0.24
Ⅰ	21	1	20	0.16	0.06	0.02, 1.37
Ⅱ	55	9	46	0.71	0.52	0.25, 2.05
Ⅲ	37	8	29
Reason of fracture				0.19	<0.01	0.06, 0.55
Low-energy trauma	75	6	69
High-energy trauma	38	12	26
Interval between injury and surgery				1.09	0.86	0.39, 3.07
≤ 3 d	67	11	56
>3 d	46	7	39
Side of fracture				0.63	0.38	0.23, 1.75
Left	61	8	53
Right	52	10	42
Location of fracture lineb					0.71
Subcapital	37	7	30	1.07	0.50	0.98, 1.17
Transverse	74	11	63	1.03	0.56	0.99, 1.08
Basal	2	0	2
Garden classification				0.13	<0.01	0.03, 0.59
Ⅰ and Ⅱ	49	2	47
Ⅲ and Ⅳ	64	16	48
Pauwels classificationc					0.02
Ⅰ	21	1	20	0.12	0.02	0.01, 0.99
Ⅱ	55	6	49	0.29	0.02	0.10, 0.87
Ⅲ	37	11	26
Reduction method				0.75	0.80	0.08, 7.10
Closed	108	17	91
Open	5	1	4
Internal fixation				3.29	0.04	1.01, 10.71
CCS	63	14	49
DHS	50	4	46
Reduction qualityd					<0.01
A	91	9	82	0.33	0.34	0.03, 3.51
B	18	8	10	2.40	0.47	0.21, 27.72
C	4	1	3