Table 3.

Univariate and multivariable odds ratio of risk factors for the prediction of re-nonunion

Variable	N	Comparison	Univariate analyses			Multivariate analyses
			OR		p value	OR		p value
			Estimate	95% CI		Estimate	95% CI
Sex	63	Female vs. male	3.197	0.92, 11.07	0.067	2.801	0.68, 11.49	0.153
Age (years)	63	< 25 vs.25~ 45 vs.> 45	0.816	0.24, 1.41	0.825	0.636	0.30, 2.17	0.589
Smoking	63	Yes vs. no	0.214	0.02, 1.34	0.036*	0.372	0.09, 1.70	0.419
Alcohol abuse	63	Yes vs. no	0.762	0.21, 1.55	0.366	0.791	0.18, 2.02	0.602
BMI (kg/m2)	63	< 30 vs.≥ 30	0.253	0.10, 1.49	0.021*	0.376	0.17, 1.74	0.314
Cause of injury	63	Traffic injury vs. falling vs. crushing	2.031	0.86, 4.37	0.102	2.310	0.86, 5.12	0.099
Fracture type	63	Closed vs. open	1.179	0.54, 2.49	0.692	0.820	0.36, 1.89	0.618
Type of IMN	63	Antegrade vs. retrograde	2.6974	0.96, 9.81	0.148	2.315	0.67, 8.19	0.178
Use of IMN locking screws	63	Dynamic vs. static	0.608	0.26, 1.38	0.237	0.826	0.34, 2.18	0.682
Site of nonunion	63	Isthmal vs. non-isthmal	0.310	0.07, 1.52	0.011*	0.403	0.11, 1.81	0.277
Primary nonunion time (years)	63	< 1.5 vs.≥ 1.5	0.918	0.28, 3.20	0.914	0.719	0.23, 2.71	0.616
Pathological type of nonunion	63	Atrophic vs. hypertrophic	0.517	0.28, 1.19	0.146	1.629	0.28, 3.26	0.701
Bone defect (mm)	63	< 5 vs. ≥ 5	0.472	0.12, 2.58	0.023*	0.528	0.18, 2.62	0.302
Primary revision method	63	ERN vs. ACP	2.125	0.09, 1.16	0.003*	1.027	0.03, 1.54	0.002*
Adjuvant ABG procedure	63	Yes vs. no	1.912	0.06, 1.08	0.027*	1.024	0.01, 1.36	0.003*

N total number of nonunions, BMI body mass index, IMN intramedullary nailing, ERN exchanging reamed nailing, ACP augmentative compression plating, ABG autogenous bone grafting, CI confidence interval, OR odds ratio

*P<0.05