Ultrasound screening in newborns: The influence of anamnestic risk factorsto congenital dysplasia of the hip

Introduction: Hereditary, pelvic respectively breech presentation or abdomi nal delivery, premature as well as post-term birth and twin pregnancy are c onsidered to be anamnestic risk factors for congenital dysplasia of the hip . The results of ultrasound hip screening of two University hospitals are p resented with special regard to the correlation of these risk factors and t he occurrence of pathologic hips. Patients/methods: 24 different physicians of the orthopaedic departments ex amined the hips of 6617 newborns (female: 3253 - 49,2%; male: 3364 - 50,8%) by ultrasound (screening). 94,6% of the examinations were performed within a period of 5 days after birth. The ultrasound examinations, the assessmen t of the echograms and classification into types of hip were performed acco rding to Graf's technique. All investigations were assessed retrospectively over the period of time with the help of documentation forms (data of newb orn baby, case history, clinical and sonographical findings, kind of therap y and procedure) and statistically checked (Chi-Quadrate-test). Results: In 436 children (6,6%) we found hips required therapy respectively control investigations (type IIa, a<55 degrees or worse; Graf's classifica tion). For the entire group we achieved the following types of hips (right/ left side): Ia - 724 (10,9%)/645 (9,8%); Ib - 3931 (59,4%)/3892 (58,8%); II a(greater than or equal to 55 degrees)- 1733 (26,2%)/1768 (26,7%); IIa (<55 degrees) - 143 (2,2%)/181 (2,7%); IIc - 55 (0,8%)/77 (1,2%); D - 20 (0,3%) /39 (0,6%); IIIa - 9 (0,1%)/11 (0,2%); IIIb - 1 (<0,1%)/3 (0,1%); IV - 1 (< 0,1 %)/I (<0,1%). Conclusions: In newborn babies with cases of hip dysplasia in their family (heredity) and pelvic respectively breech presentation at birth, as well as for girls and the left side we found a significant higher rate (p < 0,05) of hips required therapy respectively control investigations (type IIa, alp ha<55 degrees or worse; Graf's classification), A correlation of the other mentioned risk factors premature respectively post-term birth, twin pregnan cy and cases of abdominal delivary without breech presentation was not evid ent.