Development of the proximal femur begins after 6 weeks of fertilization however the primitive limb bud form after 3 weeks of fertilization.
To summarize:
- 3 weeks after fertilization
- Primitive limb bud form
- Filled with mesenchymal
- At 6 weeks, mesenchyme condensed to outline ilium, ischium, pubis, and femoral shaft (Interzone develops between femoral head and acetabulum)
- At 8 weeks:- Angulation of femoral neck into the shaft
- At 11 weeks:- Spherical femoral head (2 mm), clearly separates from the acetabulum
- Neck-shaft angle:-140-150 degrees and femoral anteversion 5-10 degrees
- The femoral shaft shows early ossification
- Femoral head and trochanters:- Cartilaginous
After birth:
- Triradiate cartilage enlarges
- Accommodate femoral head
A segment of epiphyseal cartilage is present along the posterosuperior femoral neck throughout most of the development. It is necessary for the widening of the femoral neck and posterior directed growth to decrease the amount of anteversion.
Secondary Ossification in Development of the proximal femur
Secondary ossification usually begins in the capital femur by 4 – 6 months postnatally (2-10 months)
- This process is a centrally located sphere of ossification that expand centrifugally, eventually confirming the hemispherical shape of the articular surface (by a child 6-8 years)
- Ossification of GT: (5-7 years)
- Epiphysiodesis of GT: (14 – 16 years)
- Lesser trochanter usually do not ossify until adolescence
- Fusion occurs between 15-19 years
See also: Developmental dysplasia of the hip (DDH)
See also: Vascular Supply of Proximal Femur
See also: Proximal femoral focal deficiency
