Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States

Table 1 Pearson correlation coefficients between quantified features and age for males and females

	Males			Females
	r	95%CI	P value	r	95%CI	P value
FH diameter	0.79	0.67 to 0.88	< 0.001a	-0.27	-0.5 to 0	0.047a
FH volume	0.80	0.68 to 0.88	< 0.001a	0.55	0.34 to 0.71	< 0.001a
Residual volume	0.32	0.06 to 0.54	0.016a	0.42	0.17 to 0.61	0.002a
Asphericity index	0.20	-0.01 to 0.49	0.16	0.24	0.4 to 0.75	0.058
Mean overall diameter difference	-0.25	-0.48 to 0.02	0.067	0.15	-0.12 to 0.4	0.275
Mean anterosuperior diameter difference	-0.14	-0.35 to -0.08	0.412	0.17	-0.1 to 0.42	0.211
Mean posterosuperior diameter difference	0.14	-0.13 to 0.39	0.294	0.25	-0.02 to 0.48	0.072
Mean posteroinferior diameter difference	-0.10	-0.36 to 0.17	0.450	0.12	-0.15 to 0.37	0.378
Mean anteroinferior diameter difference	-0.19	-0.42 to -0.03	0.231	0.03	-0.24 to 0.29	0.843
Max overall diameter difference	0.30	0.04 to 0.52	0.026a	0.59	0.38 to 0.74	< 0.001a
Max anterosuperior diameter difference	0.34	0.09 to 0.56	0.01a	0.58	0.37 to 0.74	< 0.001a
Max posterosuperior diameter difference	0.52	0.29 to 0.69	< 0.001a	0.64	0.45 to 0.77	< 0.001a
Max posteroinferior diameter difference	0.22	-0.05 to 0.45	0.116	0.55	0.33 to 0.71	< 0.001a
Max anteroinferior diameter difference	-0.15	-0.4 to 0.13	0.292	0.32	0.06 to 0.54	0.016a
Alpha angle	-0.48	-0.66 to -0.24	< 0.001a	-0.43	-0.62 to -0.19	0.001a

^aP < 0.05.

FH: Femoral head; CI: Confidence interval.