Table 1.

Femoroacetabular impingement parameter measurements at each degree of femoral rotation

Femoral rotation	Alpha angle (°)	Lateral center-edge angle (°)	Medial proximal femoral angle (°)
External rotation 50°	NA*	35	115
External rotation 40°	62	33	102
External rotation 20°	60	32	94
0°	46	28	89
Internal rotation 20°	44	25	83
Internal rotation 40°	39	30	78
Internal rotation 60°	39	30	70

Values are the averages of the two evaluators’ measurements; * the head-neck junction was not visible at 50° external rotation; NA = not applicable.