Rc. Hamdy et al., CORRELATION BETWEEN ULTRASOUND IMAGING AND MECHANICAL AND PHYSICAL-PROPERTIES OF LENGTHENED BONE - AN EXPERIMENTAL-STUDY IN A CANINE MODEL, Journal of pediatric orthopedics, 15(2), 1995, pp. 206-211
The right tibias of 16 adult mongrel dogs were lengthened 2.5 cm using
a uniplanar lengthening device (Orthofix). After the animals were kil
led in groups of 4 at 3, 6, 9, and 12 weeks postlengthening, ultrasoun
d imaging and mechanical and physical testing was performed. There was
a direct relationship between the percentage of intact cortices on ul
trasound imaging and the mechanical and physical properties of lengthe
ned bone. However, once 80-90% of all the cortices regained their cont
inuity, the strength of the lengthened bone was only 50-60% that of th
e control. Ultrasound imaging, therefore, may be useful in predicting
the mechanical and physical properties of lengthened bone in the early
phases of limb lengthening. Once all the cortices become continuous,
however, another method for assessment of the mechanical properties of
lengthened bone should be used.