. Author manuscript; available in PMC: 2015 Apr 6.

Published in final edited form as: J Hand Surg Am. 2008 Jul-Aug;33(6):809–819. doi: 10.1016/j.jhsa.2008.02.016

Table 5.

Radiographic Outcomes

Measurement	Cohort	3 Months	6 Months	12 Months	p-value§
Radial Inclination^†	Young	25±3.4 (24)	25±2.1 (17)	25±1.7 (15)	0.52
Radial Inclination^†	Old	25±4.1 (18)	24±5.0 (16)	24±4.5 (17)	0.52
Palmar Tilt^†	Young	9±6.9 (24)	9±5.6 (17)	9±3.8 (15)	0.84
Palmar Tilt^†	Old	9±8.2 (18)	8±7.7 (16)	10±5.8 (17)	0.84
Radial Height^†	Young	13±2.1 (24)	12±1.0 (17)	13±1.8 (15)	0.29
Radial Height^†	Old	13±3.0 (18)	12±3.1 (16)	12±2.8 (17)	0.29
Ulnar Variance^†	Young	−0.5±1.7 (24)	−0.8±1.6 (17)	−0.8±1.6 (15)	0.04
Ulnar Variance^†	Old	0.6±1.2 (18)	0.2±1.1 (16)	0.3±1.4 (17)	0.04
Articular Step-Off^‡^*	Young	13% (24)	0% (17)	7% (15)	0.37
Articular Step-Off^‡^*	Old	0% (18)	13% (16)	6% (17)	0.37
Articular Gap^‡^*	Young	8% (24)	0% (17)	6% (15)	0.93
Articular Gap^‡^*	Old	6% (18)	0% (16)	6% (17)	0.93

^†

Data reported as mean ± standard deviation (number of patients evaluated)

^‡

Data reported as % of patients with step or gap ≥ 1mm (number of patients evaluated)

93% of articular step-off measurements and 95% of articular gap measurements were 0mm, which severely skewed the distribution of results for these parameters. Thus, a calculation of the mean was not a suitable summary statistic, and it is more appropriate and meaningful to dichotomize at an appropriate cutoff value and report the percent of patients that fall within each category.

^§

Based on two-sided independent t-tests comparing outcomes at 12 months between the younger and older patient groups