Hip sonography according to Graf: practical notes for the student, the examiner and the reviewer.

Since the publication of Professor Reinhard Graf's work in 1980, Graf's technique has become the gold standard for screening Developmental Dysplasia of the Hip (DDH) in many European and non-European countries. Despite the fact that it is supported by robust literature evidence, there is criticism about its reliability and reproducibility, questioning severalaspects of the diagnostic procedure. There is, however, concern, based on recent literature, about the quality and reliability of the published data, which may, in many cases, be based on inadequate scans, and therefore any conclusions drawn have to be questioned. The aim of this review is to demonstrate the most important aspects of Graf's technique, to clarify the potential sources of confusion and to flag up the most common errors and mistakes made, either during the ultrasound examination, or during the reporting procedure. Furthermore, this review can be used as a guide for reviewers and editors and should help to enhance the quality control of publications on this subject.