The development of the upper end of the femur, with special reference to its internal architecture.

The development of the upper end of the femur was determined from radiographic analysis of the hips in 191 children and a small series of cadaver specimens from young subjects, with special attention directed to the internal architecture. At birth, linearly arranged trabeculae are present but not visible on conventional radiographs. During the latter part of the first year, trabeculae are seen on conventional studies in an apparently random orientation. Although the principal medial and lateral groups of trabeculae can be shown on coronal slab sections before the end of the first year, they cannot usually be seen on conventional radiographs until 12 to 24 months. The trabecular pattern is well established by the fifth year, although the secondary lateral and linearly oriented trochanteric trabeculae are not easily seen before adolescence. The relevance of these findings in relation to diseases of the hip and upper femur is examined.