1Institute of Biomedical Engineering, National Yang-Ming Medical College, Taipei, Taiwan 11221, R.O.C.
2Department of Biomechanics, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, U.S.A.
Abstract
The effects of strain rate on tensile failure properties of human parasagittal bridging veins were studied in eight unembalmed cadavers. While bathed in physiological saline at 37°C, the intact vessel was stretched axially by a servo-controlled hydraulic testing machine at either a low strain rate of 0.1–2.5 s−1 or a high rate of 100–250 s−1. The mean ultimate stretch ratios for low and high strain rates, respectively, were 1.51 ± 0.24 (S.D. n = 29) and 1.55 ± 0.15 (n = 34), and the ultimate stresses were 3.24 ± 1.65 (n = 17) and 3.42 ± 1.38 MPa (n = 20). Neither difference between strain rates was significant (p > 0.45). Thus, our results do not support the hypothesis that sensitivity of the ultimate strain of bridging veins to strain rate explains the acceleration tolerance data for subdural hematoma in primates [Gennarelli, R. A. and Thibault, L. E. (1982) Biomechanics of acute subdural hematoma. J. Trauma 22, 680–686].