CROSS-SECTIONAL AREA OF THE ACHILLES TENDON IN YOUNG AND ELDERLY WOMEN

Abstract

The aging process is reportedly associated with connective tissue changes although no data exists to substantiate such changes in elderly women. The present study investigated the effect of age on the cross - sectional area (CSA) of the Achilles tendon. Methods: The CSA was obtained with MRI in young (Y) healthy untrained women (n = 9, age = 29 ± 0.7 yrs (mean ± SE)) and elderly (E) healthy untrained women (n = 10, 79.4 ± 1.9 yrs). Mean CSA was obtained from 3 measures 3 cm proximal to the Achilles tendon insertion. CV for the measures was 3.4%. Achilles tendon force was obtained from maximal isometric ankle moment and moment arm data from MRI. Pearson correlation coefficients and unpaired t-tests were used for statistical evaluation. Results: (mean ± SE) Y and E did not differ in height (Y: 167 ± 3 cm, E: 163 ± 3 cm) or weight (Y: 71.3 ± 4.4 kg, E: 62.1 ± 3.6 kg). Achilles tendon CSA was greater in E (56.3+3.0 mm2) compared to Y (46.0+1.9 mm2), P < 0.01. Tendon force was greater in Y (1930 ± 393 N) compared to E (982 ± 107 N), P < 0.05. Tendon CSA was correlated to weight (r = 0.67, P < 0.05), and approached a significant relationship to tendon force (r = 0.65, P = 0.056) for Y, but not E. Conclusion: These data suggest that Achilles tendon CSA increases with age. Further, it appears that body weight and maximal strength (tendon force), in part, influences Achilles tendon CSA in young adults.