Effect of pelvic inclination on the pathogenesis of congenital hip dislocation.

The relationship of the pelvis, acetabulum, spine and femur was studied in the adult in the newborn. It was noted that when the flexed spine and pelvis derotated at or soon after birth, the femoral head dislocated anteriorly in a number of anatomic preparations, and, in the process of "unfolding," the femoral head assumed the classically recognized dislocated position. The "weak" areas in the fibrocartilaginous makeup are also described.