Ultrasound measurements of the newborn hip. Comparison of two methods in 657 newborns.

We compared ultrasound measurements using the Graf and Terjesen methods in 657 newborns. The alpha angle and femoral head coverage (FHC) were analyzed. The rate of DDH was 3.9%, according to Graf and 2.9%, according to Terjesen. The spontaneous increases in alpha angle and FHC were 5 degrees and 7%, respectively, during the first 2 months. Good accordance between the two methods was shown. A few hips were normal, according to one method and were subluxated, according to the other one. The methods gave similar results, except the percentage of "immature hips" IIa (29%) and "possible dysplastic hips" (14%). This might be a sign of better specificity of the Terjesen method. Good interosberver agreement and simple classification favor use of the Terjesen method. The method of Graf is the most commonly used and gives adequate evaluation of the hip, if the method of examination and rather complicated classification are followed closely.