A model for computer-aided analysis of biomechanical properties of the plantaris longus tendon in the rabbit.

Based on the present rapid development of user-friendly computer programs for non-linear curve fitting, the function P = a1 epsilon + a2 epsilon 3 (P = load, epsilon = strain, a1 = linear parameter, a2 = cubic parameter) for biomechanical analysis of the plantaris longus tendon in the rabbit is presented. A total of 188 plantaris longus tendons with different biomechanical properties (Plin ranging from 8.73-306.2 N) achieved by different treatments were used. With a simple load-strain sequence using a constant strain rate, load strain curves were obtained. The function was fitted to these curves up to a strain of 7.5%. The mean value for fraction of explained variance (FEV) was 0.996 (S.D. 0.002) indicating a very good fit and a high flexibility. Biomechanical and statistical analyses may be performed using only the two parameters a1 and a2 which give great data reduction and a considerable simplification of the statistical analysis.