Complex sentence: The colt's fall campaign was derailed when he was found in late July 2005 to have a hairline fracture in his left front cannon bone, near the ankle... not an uncommon injury, nor a very serious one if treated properly.
Split into simpler sentences: The colt's fall campaign was derailed when he was found in late July 2005 to have a hairline fracture in his left front cannon bone, near the ankle. This injury is not an uncommon injury, nor a very serious one if treated properly.