Pathogenesis and treatment of certain fatigue fractures of the neck of the femur.

During the unipedal phase of walking, it has been shown (Fischer, Fick & Pauwels) that the forces acting on the hip obey the fundamental laws of mechanics and can be calculated and graphically recorded fairly precisely. In these circumstances, the bones, muscles and tendons act reciprocally in such a way as to achieve the best possible motor unit, a complex machine designed to achieve the maximum work with the minimum material and the minimum expenditure of energy. This explains why, if the bones undergo changes in form or structure, complicated pathogenetic mechanisms are invoked which are interdependent and therefore give rise to disabling symptoms and/or fatigue fractures. This is illustrated in the cases presented in the present report.