Biomechanical comparison of calf and human spines.

Given the limited availability of human cadaveric specimens and their potential risk of infection, calf spines have been used as substitutes for human spines in the evaluation of spinal implants. Few biomechanical data comparing calf and human spines are available, however. The purpose of this study was to determine the biomechanical properties of the calf spine and to compare them with properties previously reported for the human spine. We determined the range of motion neutral zone, and stiffness of thoracic and lumbar calf spines (T6 to L6) under pure moment loading in flexion-extension, axial rotation, and lateral bending. These properties were shown to be similar to those of the human spine. The results suggest that the calf spine can be used as a substitute for the human spine in some in vitro tests.