Mechanical properties of ligament replacement with carbon fibres.

1. The tensile strength and modulus of elasticity of carbon fibres are comparable to those of stainless steel. 2. The small diameter (7-8 microns) produces high fibre flexibility, permitting braiding and weaving of this material. 3. The strength of braided ligament prostheses is about 2-3 times higher than the rupture strength of natural knee ligaments. 4. The elasticity and extensibility of a ligament prosthesis made of braided carbon fibres are higher than when there is a unidirectional arrangement. 5. The growth of connective tissue between the braided carbon fibres increases the elasticity and extensibility of the ligament replacement in vivo, so that 50-110% of the values for natural ligaments can be achieved. 6. The low shearing strength of the carbon fibres can be increased by a layer of collagen. 7. Intraosseous anchorages of the carbon fibre ligaments after 12 weeks of implantation exhibit strengths corresponding to 49-107% of the rupture strength of natural ligaments.