Burcu Sahin MD, Presenter: Nothing to Disclose

Elif Aktas MD, Abstract Co-Author: Nothing to Disclose

Hidir Kaygusuz, Abstract Co-Author: Nothing to Disclose

Cengiz Tuncay, Abstract Co-Author: Nothing to Disclose

Bilgin Kadri Aribas MD, Abstract Co-Author: Nothing to Disclose

Ultrasonographic Graf type 2a hips are considered as “physiologically immature”. There is very scarce information in the literature about the risk factors for specifically these Graf type 2a immature hips. Hence, the purpose of this case-control study was to examine the association between ultrasonographic Graf type 2a hips and maternal and infant risk factors of the newborns who were screened for the developmental hip dysplasia. 

In a one-year period, 679 infants were screened for developmental dysplasia by ultrasonography using Graf’s method. As an inclusion criterion, only Graf type 1 and type 2a’s were accepted. Overall, 619 infants (321 boys, 298 girls, mean age: 6.3 weeks) were eligible. A total of 60 cases (17 boys, 43 girls) with ultrasonographic Graf type 2a(+) and (-) hips and 559 controls (304 boys, 255 girls) with ultrasonographic Graf type 1 mature hips were recruited. Sociodemographic status of the infants, including gestational age, birth weights and associated congenital anomalies, maternal characteristics and, if any, the degree of consanguinity, were recorded. A backward stepwise logistic regression model was used to evaluate the relationship between idiopathic Graf type 2a hips and maternal and infant risk factors. Unadjusted and adjusted odds ratios (OR) with 95% confidence interval [CI] were calculated. 

Among maternal and infant characteristics, significant risk factors for Graf type 2a hips in the regression analysis were gestational age (>42 weeks, adjusted OR: 2.321), birth weight (>3500 gr, adjusted OR: 3,274) and gender (girls adjusted OR: 2,741). Congenital anomalies, multiple pregnancy and family history - although accepted as risk factors for developmental dysplasia - had no relation with Graf type 2a immature hips.

In conclusion, girls born after 42 weeks of gestation with an over 3500 grams of weight had a more than twice the risk for a physiologically immature Graf type 2a hips. To obtain more accurate results, a population-based screening study with an increased number of cases and controls should be performed in future studies.

For ultrasonographic screening of developmental hip dysplasia,we recommend that gender,birth weight and gestational age should be questioned in order to be alert for Graf type 2a hips. 

Sahin, B, Aktas, E, Kaygusuz, H, Tuncay, C, Aribas, B, Analysis of Risk Factors for Ultrasonographic Graf Type 2a Hips in Developmental Dysplasia: A Hospital-based Case-control Study with a Screening Program.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008718.html