[Echography in the study of the neonatal hip: the diagnostic-therapeutic implications of type-IIa (borderline) findings].

Sonography (US) is a useful method in the early diagnosis of congenital hip dislocation; X-ray examination exhibits limitations due to high false-positive and false-negative rates. The advantages of US include: non-invasiveness, direct visualization of muscle and cartilage, dynamic demonstration of anatomical structures, and possible diagnosis in neonatal age. Therefore, US can be used as a screening or targeted diagnostic technique in selected newborns with clinical suspicion and/or risk factors. In this paper the authors report their experience in 1271 patients (721 females, 550 males), aged 1 day to 7 months, who were examined with US for the diagnosis of congenital hip dislocation. The newborns were divided into two groups at first examination: a) the screening group included 524 consecutive newborns (F = 266, M = 258) from S. Chiara Regional Hospital in Trento, and b) a selected group of 747 newborns (F = 455, M = 292) with clinical suspicion and/or risk factors, who had been selected in the Trento area. According to Graf's classification, the results of US in 2542 neonatal hips, were: 2346 (92.3%) normal hips, 171 (6.1%) type IIa hips, and 24 (1.6%) pathological hips. In the selected group (1494 hips) we observed: 1351 (90.4%) normal, 119 (8%) type IIa, and 24 (1.6%) pathological hips (IIb, IIc, D, III). In the screening group (1048 hips) we detected: 995 (95%) normal hips (Ia/Ib), 52 (4.9%) type IIa, and 1 (0.1%) pathological hips (D). Our experience suggests that US is a useful method in selected newborns with clinical suspicion of congenital hip dislocation and/or risk factors. US limitations consists in the dispersion of type IIa hips. Moreover, the need emerged for complete cooperation between pediatrician, radiologist, and orthopedist to optimize the cost/benefit ratio.