Prospective evaluation of newborn soft-tissue hip "clicks" with ultrasound.

Fifty infants with soft-tissue hip "clicks" persisting after age 3 months were prospectively studied by using ultrasound. All children demonstrated a stable hip examination by Barlow and Ortolani maneuvers; however, a click was palpated with abduction and adduction of the hip. Static ultrasonography demonstrated an average alpha angle of 63 degrees in uninvolved hips and 62 degrees in the clicking hips. All hips had > 50% femoral-head coverage by the acetabulum. Dynamic ultrasound examination was normal in all cases. The soft-tissue clicks were not related to instability in this series of 50 infants.