Biomechanical and physical properties of lengthened bone in a canine model.

Reports on the mechanical and physical properties of lengthened bone after completion of the lengthening process remain scarce. Varied results of torsional testing of lengthened bone have been reported. Furthermore, torsional testing provides information on the shear properties of the tissue but does not reflect the elastic properties obtained from tensile, compressive, or bending tests. The present study evaluated the mechanical properties of lengthened bone at various time points, using a uniaxial tension test. Physical properties (density and ash weight) were determined as well. Results indicate that the tensile properties of the lengthened bone increase with time after the completion of lengthening, but they remain significantly weaker than controls (50%) even after 12 weeks. Density and ash weight measurements also increased with time, correlating with the increase in the tensile mechanical properties.