The effect of shock wave therapy on acute fractures of the tibia was studie
d in eight adult dogs. A fracture with a 3-mm gap was created in both tibia
s and the fractures were fixed internally with a small metallic plate and s
crews. Each ofthe right limbs received 2000 impulses of shock waves at 14 k
V whereas the left limbs were used as controls, The evaluations included th
e callus formations based on serial radiographic examinations at 1, 4, 8, a
nd 12 weeks and histologic examinations at 12 weeks for tissue distribution
including bone tissues. Based on radiographic findings, there was no stati
stically significant difference in the amount of callus formation between t
he treated and the control groups at 8 weeks or less. However, the radiogra
phic findings at 12 weeks statistically showed more callus formations in th
e treated group. In histologic examinations, there was significantly more c
ortical bone formation in the treated group at 12 weeks and the bone tissue
s were thicker, denser, and heavier, Shock wave therapy enhanced callus for
mation and induced cortical bone formation in acute fractures in dogs at 12
weeks, The effect of shock wave therapy seemed to be time-dependent at 3 m
onths.