The influence of intermittent micromovement upon the healing of experimental fractures

The preliminary results are presented of an investigation into the influence of intermittent axial cyclical loading, applied for a very short period each day (500 cycles over 17 minutes), upon experimental fracture healing in sheep tibiae. The application of the intermittent stimulus is associated with the earlier appearance of external callus seen within two weeks of osteotomy. There is also a significant increase in fracture stiffness to bending appearing at eight to ten weeks from osteotomy in the cyclically loaded group. Post mortem torsional stiffness assessed at 12 weeks from osteotomy is significantly greater in the loaded group.