Effects of oestrogen upon tensile properties of healing fractured avian bone.

The present work considers some of the effects of oestrogen treatment on the biomechanical properties of long bones during the process of osteosynthesis. The influence of the steroid was assessed by determining the tensile strength properties of treated and untreated healing fractured ossa radii. The ultimate tensile strength and modulus of elasticity were determined at one and two week post-fracture induction. In general, oestrogen treatment decelerated healing process of long bones. This was indicated by a significantly reduced ultimate tensile callus strength of oestrogen-treated birds over a two week period post-fracture induction. The same group also exhibited a significant increase in callus cross-sectional area while the elastic moduli of their bones were not significantly different at either one or two weeks post-fracture induction.