Assessment of the correlation between commonly used radiographic parameters in normal, subluxated and dislocated hips.

The correlations between the commonly used radiographic parameters, center-edge angle (CEA), acetabular-head index (AHI), acetabular index angle (AIA), acetabular angle (AA) and ACM angle, in normal, subluxated and dislocated hips were investigated in the radiographs of 364 normal, 23 subluxated and 19 dislocated hips of patients between 5 and 18 years of age. A significant correlation was observed between all the parameters in normal hips. A significant correlation between AIA and the other four parameters, and between CEA-AHI and AA-ACM, was noted in subluxated hips. AIA-AA and AIA-ACM had significant correlations in dislocated hips. It was concluded that measurement of more than one radiographic parameter might be better to exactly evaluate the radiographic hip anatomy in developmental dysplasia of the hip.