Table 3.

Anatomic characteristics of acetabular dysplasia

Variables	Dysplastic hips (n = 50)
Femoral neck length (mm; mean ± SD)	50 ± 5
Head center height (mm; mean ± SD)	59 ± 6
Greater trochanteric height (mm; mean ± SD)	−5 ± 3
Femoral head diameter (mm; mean ± SD)	46 ± 3
Femoral offset (mm; mean ± SD)	37 ± 4
Neck-shaft angle (degrees; mean ± SD)	136 ± 5
Femoral version (degrees; mean ± SD)	19 ± 12
Alpha angle* (degrees; mean ± SD)
9:00	36 ± 3
10:30	35 ± 3
12:00	39 ± 3
1:30	49 ± 6
3:00	44 ± 8
Maximum alpha angle* (degrees; mean ± SD)	53 ± 6
Maximum alpha angle location* (o’clock; mean ± SD)	2:00 ± 0:45
Femoral head-neck offset* (mm; mean ± SD)
12:00	9 ± 1
1:30	6 ± 1
3:00	8 ± 2
Femoral head-neck offset ratio (mean ± SD)
12:00	0.21 ± 0.03
1:30	0.14 ± 0.03
3:00	0.17 ± 0.03

*Alpha angle, head-neck offset, and head-neck offset ratio measured according to the clock position.