Mathematical simulation of osteotomy. Numerical analysis and results (Q1917883)

Osteophytes, cysts as well as arthrodesis on the contact boundary between the head of the joint and the acetabulum originate in highly loaded human joints. Osteophytes originate from bone metaplasia of the synovial membrane and joint capsule in which all stages of both phylogenesis and ontogenesis of bone formation may be reproduced. In a completely developed osteoarthritic hip joint, three principal osteophytes on the femoral head as well as three principal osteophytes on the acetabulum are observed. The cysts contain bone marrow and cartilage from metaplasia of the bone marrow. The purpose of proximal femur osteotomy is to bring the femoral head into a new position inside the acetabulum. The present widespread tomographic measurement methods, i.e., computed tomography and magnetic resonance imaging,and automatic three-dimensional reconstructions also involve numerous new points of view for planning femoral osteotomy. Earlier methods were based on descriptive geometry, on the triangulation method and on basic kinematic technique. We discuss mathematical models based on the contact problems and finite element methods which provide a new method of solving surgical problems of osteotomy.