title: Evaluation of strength of healing fractures with dual energy Xray absorptiometry.
abstract: Dual energy xray absorptiometry was investigated as a method for evaluation of the strength of closed tibial fractures. In 40 goats, a closed midshaft fracture was created in the left tibia. The fractures were stabilized with an external fixator. After 2 weeks (n = 21) and after 4 weeks (n = 19), both tibias were explanted and, using dual energy xray absorptiometry, bone mineral density and bone mineral content were measured in a 1 cm region. With nondestructive bending tests, area ratio and stiffness index were determined and torsional strength and torsional stiffness were determined with a torsional test to failure. Linear regression analysis was used to calculate the squared correlation coefficients for the relations between dual energy xray absorptiometry and the outcome of the mechanical tests. The squared correlation coefficients for the relation between bone mineral density and torsional strength, torsional stiffness, and area ratio and stiffness index were 0.72, 0.76, 0.64, and 0.72, respectively. The squared correlation coefficients for the relation between bone mineral content and these mechanical parameters were 0.72, 0.77, 0.63, and 0.77, respectively. The results using dual energy xray absorptiometry indicate the strength of healing closed fractures. Additional research is required to investigate specific aspects of this technique.
authors.affiliation: Department of Traumatology, Academic Hospital Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: T J
authors.initials: TJ
authors.lastname: Blokhuis
authors.forename: F C
authors.initials: FC
authors.lastname: den Boer
authors.forename: J A
authors.initials: JA
authors.lastname: Bramer
authors.forename: A
authors.initials: A
authors.lastname: van Lingen
authors.forename: J C
authors.initials: JC
authors.lastname: Roos
authors.forename: F C
authors.initials: FC
authors.lastname: Bakker
authors.forename: P
authors.initials: P
authors.lastname: Patka
authors.forename: H J
authors.initials: HJ
authors.lastname: Haarman
mesh_terms: D015502:Absorptiometry, Photon; D000818:Animals; D001696:Biomechanical Phenomena; D004195:Disease Models, Animal; D005260:Female; D017102:Fracture Healing; D006041:Goats; D016014:Linear Models; D011897:Random Allocation; D013978:Tibial Fractures / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome