Table 2.

Intraoperative and postoperative outcomes between the GMSV and lithotomy groups.

Characteristics	GMSV Position Group	Lithotomy Position Group	t/χ2	P value
Number of patients, (n)	78	80
Operative time (min)	41.35 ± 7.32	55.21 ± 8.25	11.160	＜0.001
Use of stone retrieval baskets, n (%)	3 (3.85)	10 (12.50)	3.917	0.048
Postoperative hospital stay (days), mean ± SD	2.12 ± 0.65	2.31 ± 0.62	1.880	0.062
SFR on postoperative day 1 (Grades A + B), n (%)	68 (87.18)	59 (73.75)	4.516	0.034
SFR at 1 month after surgery (Grades A + B), n (%)	72 (92.31)	65 (81.25)	4.190	0.041
Secondary procedures, n (%)	1 (1.28)	2 (2.50)	0.001	0.982
Postoperative hemoglobin level, (g/L)	130.2 ± 19.3	131.8 ± 19.9	0.513	0.609
Total position-related complications	2 (2.56)	3 (3.75)	0.001	0.977
Skin injury	1 (1.28)	1 (1.25)
Joint injury	1 (1.28)	0 (0.00)
Nerve injury	0 (0.00)	2 (2.50)
Overall complicationsa, n (%)	8 (10.26)	12 (15.00)	0.316	0.574
Grade I
Fever (≥38.0 °C)	2 (2.56)	3 (3.75)	0.001	0.977
Nausea/vomiting	4 (5.13)	6 (7.50)	0.082	0.775
Subcapsular renal hematoma	1 (1.28)	2 (2.50)	0.001	0.974
Persistent hematuria	2 (2.56)	3 (3.75)	0.001	0.977
Grade II
Pleural effusion	0 (0.00)	0 (0.00)	-	-
Ureteral contusion	1 (1.28)	2 (2.50)	0.001	0.974
Blood transfusion	0 (0.00)	0 (0.00)	-	-
Grade III-IV
Steinstrasse (Grade III)	0 (0.00)	0 (0.00)	-	-
Ureteral perforation (Grade IV)	0 (0.00)	0 (0.00)	-	-
Sepsis (Grade IV)	1 (1.28)	2 (2.50)	0.001	0.974
Stone composition
Calcium oxalate stones, n (%)	59（75.64）	60（75.00）	0.009	0.926
Infection-related stones, n (%)	10（12.82）	11（13.75）	0.030	0.863
Uric acid stones, n (%)	7（8.97）	7（8.75）	0.003	0.960
Cystine stones, n (%)	2（2.56）	2（2.50）	0.231	0.631

VAS, visual analogue scale.

Based on the Clavien–Dindo classification system, some patients experienced multiple complications simultaneously.

^aSFR was graded as follows: Grade A (no residual fragments), Grade B (residual fragments 0–2 mm), Grade C (residual fragments 2.1–4 mm), and Grade D (residual fragments > 4 mm).