Single vs double headless compression screw fixation for scaphoid nonunion

Table 1 Baseline demographics and clinical characteristics, n (%)/mean ± SD

Variable	1-screw group (n = 15)	2-screw group (n = 8)	Test statistic	P value
Age (years)	32.80 ± 9.41	23.88 ± 7.30	t = 2.326	0.030a
BMI (kg/m2)	28.84 ± 4.15	25.84 ± 2.18	t = 1.894	0.072
Dominant hand			N/A	1.000
Right	14 (93.3)	7 (87.5)
Left	1 (6.7)	1 (12.5)
Comorbidities			N/A	0.558
None (free)	13 (86.7)	8 (100.0)
DM + UC	1 (6.7)	0 (0.0)
Hyperlipidemia	1 (6.7)	0 (0.0)
Pre-operative DISI	7 (46.7)	7 (87.5)	N/A	0.086

^aP < 0.05.

Continuous variables (age, body mass index) were analyzed using an independent samples t-test. Categorical variables (Dominant Hand, Comorbidities, Pre-Operative dorsal intercalated segment instability) were analyzed using Fisher’s exact test. N/A indicates Fisher’s exact test was used, which computes exact probability directly without generating a standardized test statistic. BMI: Body mass index; DM: Diabetes mellitus; UC: Ulcerative colitis; DISI: Dorsal intercalated segment instability; N/A: Not applicable.