The development of ultrasound; Diagnostic ultrasound in orthopedics; The infant hip: a survey of past and present diagnostic methods; Development, anatomy, and pathoanatomy of the hip; Sonographic morphology of the infant hip; Classification of hip joints on the basis of ultrasound findings; Standard plane of section, measuring techniques, and sources of error; Sonographic assessment of hip maturity using a sonometric scale; Dynamic hip examination monitored by ultrasound; Sonographic case report of the hip; Practical approach to difficult cases; Procedure for infant positioning and scanning technique; Statistical analysis; Sonographic follow up program and therapeutic consequences; Sonographic follow-up examination.