The significance of the biomechanical properties of costal cartilage in the timing of ear reconstruction surgery

Background: We aimed to investigate the biomechanical changes of costal cartilage in a broad age range in order to provide a theoretical reference as to the optimal age to use costal cartilage in ear reconstruction surgery. Method: Ninety patients (age 5-25 years) were categorised into three groups according to age: children, adolescent and adult. We investigated the biomechanical properties of rib cartilage including stress-strain relation, stress-induced relaxation, creep and maximum resistance to stretch. The results were analysed using one-way analysis of variance. Result: The children's groups performed best and the adolescent groups performed worst in terms of the four biomechanical properties (tensile strength, stress-stain, stress relaxation and creep) of rib cartilage. After statistical analysis, it was found that the differences were significant (P < 0.05). Conclusion: Significant differences in the biomechanical properties of costal cartilage exist with age. We recommend that when autogenous rib cartilage is used in ear reconstruction it is most favourable to operate in childhood (age 5-10). (C) 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.