Diagnosis of the development dislocation of hip in infants by measuring three radiological hip lines

Abstract

Objective To evaluate three hip lines measurement in diagnosis of developmental dislocation of the hip (DDH) in infants. Methods One hundred and eighty infants with suspected diagnosis were studied. In addition to routine physical examination, X-ray of both hips were taken and the Shenton's lines and CE angels were measured. Three hip lines were measured from the midpoint of the femoral metaphysis to upper margin, lower margin and center of the acetabulum respectively. Results Of the 180 infants, there were 122 unilateral( 122 hips)and 58 bilateral developmental dislocations of hip( 116 hips). The three hip lines were measured in all the 238 hips and the DDH was diagnosed. The three lines of the normal lateral hips in the 122 unilateral cases were also measured and the equal length was found in 120 normal hips (98.3%). Furthermore, the length of the three lines of the unsuccessful closed reduction of hips was different. Conclusions Measurement of the three hip lines provides an accurate diagnosis for DDH in infants. This is useful in infants whose osteoepiphysis of femoral head were not formed. For those who undergo treatment, measurement of the three hip lines is useful for assessment of the progress. Key words: Infant; Hip dislocation; Acetabulum