Quantifying the effect of ischemia on epiphyseal growth in an extremity replant model

Warm ischemia (21 degrees C) of 0, 2, 4, 6, or 8 hours was produced in a modified hindlimb preparation of 35 10-week-old Lewis rats by amputation. Subsequent microvascular anastomoses of each hindlimb to a syngeneic animal was done after which fluorochrome bone labels were administered 5 minutes after operation and on day 14 after operation. Epiphyseal plate growth (that between bone labels) was analyzed histomorphometrically and statistically. Epiphyseal plate growth was found to have a linear inverse relationship to ischemia time with a correlation coefficient (r) of -0.653 and high statistical significance (p less than 0.001). Overgrowth occurred at all ischemic periods except 8 hours, and vascular pedicle patency decreased as ischemia time progressed.