Carbon fibre and fibre lamination in prosthetics and orthotics: some basic theory and practical advice for the practitioner.

Introduction The first experiments with carbon fibre (CF) in prosthetics and orthotics were probably made by Mr. Nigel Ring, Chailey Craft School and Heritage, Sussex, England, around 1966. This was in the very early days of C F technology, just a couple of years after the introduction of the very expensive stretched high modulus fibre. It was a very promising new technology, but it turned out, that there were some very expensive lessons to be learned by the high tech industry, before the new material could be safely used in product development. The most famous of these lessons is probably the one when the first use of carbon fibre in jet engine turbine blades failed after the production had started, with disastrous economical consequences for the company. Mr. Ring tried to make light, stiff torso sockets for upper l imb amelics, and soon after Dr. David Simpson, Edinburgh, the author and maybe some others followed. The results were interesting but the costs were prohibitive and it must be confessed, that we did not use the fibres very intelligently at the time. In 1972 Mr. Bengt Östberg at our Een & Holmgren Uppsala branch tried to reinforce aluminium braces with carbon fibre prepreg after final adjustment of the brace. The aluminium was then used as a core in the final product. The results were excellent, but the manufacturing technique, including the use of a large and heavy autoclave, was too impractical for use in prosthetic and orthotic service. In the late 1970s Mr. Össur Kristinsson, Iceland, invited us to join him in the development of his new trans-femoral socket concept, the flexible socket. A key component in this concept is a very stiff upright, and for this he suggested the use of CF. Since then the author has maintained a very productive contact with Mr. Kristinsson, although many others have provided very important inputs to our development and to our education programmes. We can now look back at more than a quarter of a century playing around with C F and more than a decade routinely using it in prostheses, orthoses, corsets and orthopaedic footwear, and we are far from the only ones. C F is now widely used in prosthetics and orthotics and many allied industries, pioneered by Blatchford, UK, (prosthetic components) and Proteor, France (orthotic components) have introduced CF products and applications, one of the most recent ones the very interesting Icelandic Masterstep foot. Many of these products are beautiful examples of good professionalism in