FROM STRUCTURE TO PROCESS, FROM ORGAN TO CELL - RECENT DEVELOPMENTS OF FE-ANALYSIS IN ORTHOPEDIC BIOMECHANICS

The introduction of finite element analysis (FEA) into orthopaedic bio mechanics allowed continuum structural analysis of bone and bone-impla nt composites of complicated shapes (Huiskes and Chao, J. Biomechanics , Vol. 16, 1983, pp. 385-409). However, besides having complicated sha pes, musculoskeletal tissues are hierarchical composites with multiple structural levels that adapt to their mechanical environment. Mechani cal adaptation influences the success of many orthopaedic treatments, especially total joint replacements. Recent advances in FEA applicatio ns have begun to address questions concerning the optimality of bone s tructure, the processes of bone remodeling, the mechanics of soft hydr ated tissues, and the mechanics of tissues down to the microstructural and cell levels. Advances in each of these areas, which have brought FEA from a continuum stress analysis tool to a tool which plays an eve r-increasing role in the scientific understanding of tissue structure, adaptation, and the optimal design of orthopaedic implants, are revie wed.