A two-stage retrospective analysis to determine the effect of entry point on higher exit of proximal pins in lateral pinning of supracondylar humerus fracture in children

Table 1 Possible influencing factors of the exit point distribution in the first stage of the study

	Exit zones				Total	p value^$
	− 2	− 1	+ 1	+ 2	Total	p value^$
Gender
M	17	49	16	7	89 (55.3%)	0.133
F	9	39	22	2	72 (44.7%)	0.133
Age group
≤ 6	18	56	31	7	112 (69.6%)	0.226
> 6	8	32	7	2	49 (30.4%)	0.226
Side
Right	10	32	19	2	63 (39.1%)	0.369
Left	16	56	19	7	98 (60.9%)	0.369
Pin size
1.6 mm	16	49	30	5	100 (62.1%)	0.098
2.0 mm	10	39	8	4	61 (37.9%)	0.098
Gartland type
II	6	31	12	3	52 (32.3%)	0.724
III	20	57	26	6	109 (67.7%)	0.724
Fracture line location
Transolecranon	23	75	37	9	144 (89.4%)	0.153
Supraolecranon	3	13	1	0	17 (10.6%)	0.153
Fracture line pattern
Transverse	26	80	37	9	152 (94.4%)	0.471
Medial oblique	0	3	1	0	4 (2.5%)
Lateral oblique	0	5	0	0	5 (3.1%)
Entry points on anterior-posterior view
Lateral*	24	84	34	9	151 (93.8%)	0.263
Medial*	2	4	4	0	10 (6.2%)	0.263
Entry points on lateral view
Posterior^#	25	75	36	7	143 (88.8%)	0.239
Anterior^#	1	13	2	2	18 (11.2%)	0.239
Total	26	88	38	9	161

^$The p value describes the difference in distribution of pins in the exit zones between/among subgroups (χ² test)
*Lateral: proximal lateral pins laid lateral to the ONC or in the lateral third of the ONC. Medial: proximal lateral pins laid in the medial two thirds of the ONC
^#Posterior: proximal lateral pins laid posterior to the ONC or in the posterior third of the ONC. Anterior: proximal lateral pins laid in the anterior two thirds of the ONC

ISSN: 1749-799X