Purpose: The author aims to objectivize simple parameters of normal anatomy of the hip related to age and sex in children as a contribution to interpretation criterions in medical imagery. Materials and methods. He has examined antero-posterior radiographs of 155 normal hips (right: 81; left: 74) among 129 children aged from six months to 16 years (mean age=8.9 years). They were 86 boys and 43 girls (ratio M/F=2).
Results: The results are as follow:--the joint space of the hip (JS/H): cranial part (cranial joint space: CJS/H): 5.5 mm +/- 0.5; medial part (medial joint space: MJS/H): 7 mm+/-0.5; --the bony roofingless part of the femoral head (BR/FH): 1-6 years: 1-3 mm; 7-13 years: 4-5 mm; 14-16 years: 6 mm; --the neck shaft angle of the femur (NSA/F); 1-6 years: 150 degrees-140 degrees; 7-16 years: 135 degrees; --the horizontal and the vertical diameters of the femoral head (HD/FH; VD/FH); x being the age of the children, the HD/FH grows according to a linear regression function as Ydh = 2x + 13+/-2 and the VD/FH as Ych = 2x + 18+/-2; --the centre acetabular edge index (CEI): the CEI decreases from 1 to 16 years: medium: 2.75-1.77; maximum: 2.31-1.67; minimum: 3.62-1.91; --the centre-acetabular cartilage index (CCI)): the CCI grows from 1 to 16 years: medium: 0.57-0.70; maximum: 0.62-0.73; minimum: 0.5-0.68. No influence of the side of the hip nor the sex of the children is observed.
Conclusion: This study brings out exhaustive and original data on the growth velocity of the hip skeleton in children and supplies with criterions of diagnosis according to age in childhood.