Engineering in Medicine

Research on biomaterials has been undertaken at the University of Liverpool for the last ten years since the establishment of a Bioengineering Unit in 1969. During recent years involvment in biomaterials research has increased and a considerably greater co-operative effort has developed, leading to the formation of a Centre for Biomaterials Research in 1978. Three different departments are represented in this joint venture, the Department of Dental Sciences within the School of Dental Surgery, the Bioengineering Unit within the Faculty of Medicine and the Metallurgy and Materials Science Department withing the Faculty of Engineering Science. The biomaterials activities of these three departments, which in each case represent one part of the total research activities of that department are directed by Dr D. F. Williams, Mr D. Annis and Professor D. Hull respectively. Each department naturally has its own area of expertise and joint programmes of work are undertaken to maximize this expertise and the facilities that are available.

The internal equilibrium of human joints has been dealt with by many investigators, either as a means for better understanding and treating joint diseases or as a basis for prosthetic design. In all cases there is less information than needed for an accurate solution, and the investigators have to use simplifying geometry and restricting assumptions. In this work a permutation method was used, which takes advantage of big computer facilities in order to reduce the number of assumptions needed. The method was used for the case of the knee joint. The results were compared to those available using a regular method, showing the permutation one to be superior.

The manufacture, calibration and use of a simple, cheap instrumented sole assembly, suitable for use in a clinical or laboratory environment with normal or pathological feet, is described and discussed.