Comparison of freehand technique and a novel laser guiding navigation in distal locking of femoral intramedullary nails: a randomized controlled trial

Table 2 The results of two groups

Parameter	Laser group	FH group	t/χ²/Z value	P value
First success rate***	93.75% (30/32)	62.5% (20/32)	9.143	0.002
Distal locking time(min)*	10 (9/11)	19.5 (17.25/21)	4.83	< 0.0001
Distal locking radiation exposure time (s)*	46.5 (41.25/51.75)	105 (88.25/140)	4.807	< 0.0001
Amount of bleeding (mL)*	60 (50/100)	150 (105/192.5)	3.61	0.0003
VAS (before operation)*	8 (8/9)	8 (8/9)	0.202	0.8402
VAS (1 week after operation)*	2 (2/2)	2 (2/2.75)	1.222	0.2217
Harris score**	88.63 ± 2.16	87.25 ± 2.86	− 1.534	0.1354
Healing time (week)**	17.25 ± 1.65	17.31 ± 1.45	0.114	0.9102

^*Non-normal continuous data was presented as median (lower/upper quartile), and the statistical result was Z value
^**The normal continuous data was presented as mean ± standard deviation, and the statistical result was t value
^***Categorical variables were presented as frequency and percentage, and the statistical result was χ² value

ISSN: 1471-2482