Table 3.

Relationships between 2D radiographic measurements and 3D measurements of coverage.

	TC	Ant	Post	ALC	AMC	PLC	PMC
3D Measurements
Extrusion index	r = –0.37	r = 0.21	r = –0.45	r = –0.021	r = 0.28	r = –0.38	r = –0.30
	β = –42.2	β = 35.7	β = –103.6	β = –3.20	β = 66.9	β = –182.8	β = –41.3
	p = 0.03 a	p = 0.2	p = 0.007 a	p = 0.9	p = 0.1	p = 0.03 a	p = 0.08
Crossover ratio	r = 0.29	r = 0.075	r = 0.21	r = 0.16	r = 0.005	r = 0.22	r = 0.05
	β = 9.03	β = 4.68	β = 9.99	β = 7.92	β = 0.43	β = 18.49	β = 2.59
	p = 0.2	p = 0.8	p = 0.4	p = 0.5	p = 1.0	p = 0.4	p = 0.9
2D Measurements
Posterior wall distance	r = 0.57	r = –0.18	r = 0.62	r = 0.07	r = –0.29	r = 0.61	r = 0.34
	β = 0.59	β = –0.28	β = 1.27	β = 0.10	β = –0.63	β = 2.64	β = 0.42
	p < 0.001 a	p = 0.3	p < 0.001 a	p = 0.6	p = 0.09	p < 0.001 a	p = 0.05 a
Acetabular angle	r = –0.013	r = 0.16	r = –0.13	r = –0.037	r = 0.21	r = –0.16	r = 0.04
	β = –0.025	β = 0.46	β = –0.50	β = –0.095	β = 0.83	β = –1.30	β = 0.09
	p = 0.9	p = 0.4	p = 0.5	p = 0.8	p = 0.2	p = 0.3	p = 0.8
Acetabular index	r = –0.21	r = 0.18	r = –0.31	r = –0.055	r = 0.26	r = –0.38	r = 0.024
	β = –0.27	β = 0.34	β = –0.77	β = –0.093	β = 0.69	β = –2.04	β = 0.036
	p = 0.2	p = 0.3	p = 0.08	p = 0.8	p = 0.1	p = 0.03 a	p = 0.8
Lateral center-edge angle	r = 0.48	r = –0.086	r = 0.47	r = 0.17	r = –0.21	r = 0.44	r = 0.23
	β = 0.49	β = –0.13	β = 0.96	β = 0.23	β = –0.44	β = 1.92	β = 0.28
	p = 0.005 a	p = 0.6	p = 0.005 a	p = 0.3	p = 0.2	p = 0.01 a	p = 0.2

^a Significant relationships

TC: total coverage; Ant: anterior coverage; Post: posterior coverage; ALC: anterolateral coverage; AMC: anteromedial coverage;

PLC: posterolateral coverage; PMC: posteromedial coverage; r: correlation coefficient; b: regression coefficient (slope).