A paper recently published by Kolios and colleagues addresses the effect of estrogen and alendronate on the healing of osteoporosis-related fractures in mice . Three groups of ovariectomized mice and one control group received a soy-free diet. Two of the three groups of castrated mice additionally received either 17β-estradiol or alendronate in the diet. After 10 weeks, a metaphyseal tibia osteotomy and T-plate fixation were performed on all mice. After a 5-week healing period, the mice were sacrificed and the fracture callus was evaluated qualitatively by biomechanical bending and quantitatively by micro-radiographic sections. It was found that the 17β-estradiol-treated mice had superior biomechanical properties compared to all other groups and that this could be attributed to healing in the callus that occurred in a physiological fashion with improvement in the trabecular structure. The alendronate-treated group did not show these properties and results were only marginally better than the results in the ovariectomized mice that did not receive 17β-estradiol or alendronate but worse than the results in the control group. The authors conclude with a suggestion that a short treatment course with 17β-estradiol in the first weeks after fracture might be beneficial in humans. It is argued that, with such a limited (not defined) treatment course, benefits will outweigh negative effects.
Tobie J. De Villiers
Panorama MediClinic and Department of Obstetrics & Gynecology, University of Stellenbosch, Cape Town, South Africa
Kolios L, Hoerster A, Sehmisch S, et al. Do estrogen and alendronate improve metaphyseal fracture healing when applied as osteoporosis prophylaxis? Calcif Tissue Int 2009 Dec 1. Epub ahead of print.
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