China
Africa
Explore chapters and articles related to this topic
Congenital and Developmental Abnormalities
Published in Harry Griffiths, Musculoskeletal Radiology, 2008
In order to assess the radiographs adequately, a number of lines should be drawn and measurements be made. The classical lines are: Hilgenreiner’s line is a horizontal line drawn through both triradiate cartilages (Fig. 38A).The acetabular index or the acetabular angle is a line drawn from where the horizontal line and the triradiate cartilage meet, and measures the angle of the acetabulum (Fig. 38A, left hip). Sharp classified this first and noted that in children under the age of 3 years, the angle is often as high as 45°, but by 14 years of age, the angle drops to 41°, and, in most adults, it is 35°.Center edge angle is an angle drawn between a vertical line, which is dropped through the epicenter of the femoral head, and a second line drawn from this epicenter to the margin of the acetabulum (Fig. 38B). The vertical line is vertical to Hilgenreiner’s horizontal line. This measurement was first described by Wiberg. In very young children, it is difficult to measure, but by age five, it measures about 19°. It continues to increase until, in adults, it measures 25° to 30°. Interestingly, the orthopedic community does the opposite and drops a vertical line from the outer margin of the acetabulum, and then an angled line to the center of the femoral head. Obviously these readings are identical (Fig. 38B).Femoral neck/shaft angle: At birth, the upper femur is relatively vertical, and the neck/shaft angle measures 150°. However, as the child bears weight, this angle decreases and in most adults, it is about 130°. This line is reproduced by drawing a vertical line through the femoral shaft, and then a line through the center of the femoral neck (Fig. 38C).Shenton’s line is used by most of the medical students as it is easy to remember. Draw a line along the undersurface of the femoral neck and continue it onto the undersurface of the pubic ramus (i.e., the top of the obturator foramen in normal people). This line is said to resemble a Roman arch. This line is broken in someone with DHD (Fig. 38D).Width of space between the vertical component of the ischium and the proximal femur: This measurement really works only if you have a normal side for comparison. If the child has bilateral congenital hip dysplasia, then it is difficult to measure. However, in children with DHD, this space is markedly widened (Fig. 38E).
What is the association between MRI and conventional radiography in measuring femoral head migration?
Published in Acta Orthopaedica, 2021
Hans-Christen Husum, Michel Bach Hellfritzsch, Mads Henriksen, Kirsten Skjaerbaek Duch, Martin Gottliebsen, Ole Rahbek
To calculate CMP we measured the distance between the medial and lateral sides of the cartilaginous edge of the femoral head (A) as well as the distance between a vertical line through the most lateral aspect of the cartilaginous acetabular roof perpendicular to Hilgenreiner’s line and the lateral side of the cartilaginous edge of the femoral head (C). CMP was then calculated as: CMP = C/A x 100% (Figure 1).
Pelvic obliquity and measurement of hip displacement in children with cerebral palsy
Published in Acta Orthopaedica, 2018
Gunnar Hägglund, Mikael Goldring, Maria Hermanson, Elisabet Rodby-Bousquet
MP is the gold standard for measuring hip displacement and is used in most hip surveillance programs (Dobson et al. 2002, Hägglund et al. 2014). In MP, the lateral displacement is related to Hilgenreiner’s line. This means that the measurement of MP is not related to a PO.