OSTEONEOGENESIS BY CALLUS DISTRACTION AND DISTRACTION EPIPHYSIOLYSIS

X-rays were reviewed after callus distractions (50 cases) and distract ion epiphysiolysis (10 cases) in 45 patients. With the aid of a comput erized digitization system for analogue films, the relative x-ray dens ity of the distraction area was determined in the medial, lateral, ven tral and dorsal surface areas, and in the median line of the callus ti ssue. Bone formation became evident within 21,7 +/- 3,7 days post-dist raction in the thigh and 25,4 +/- 4,9 days in the shank. The lowest de nsity values were found at the end of the distraction phase followed b y a continual increase in x-ray density in the fixation phase. There w as a significant decrease in callus x-ray density in the shank from la teral to medial and from dorsal to ventral, and in the thigh from medi al to lateral and from dorsal to ventral. When the corticotomized call us distraction is compared to the distraction epiphysiolysis without c orticotomy it becomes apparent that the differences between lateral - medial x-ray densities and dorsal - ventral x-ray densities were signi ficantly greater in the group with callus distraction. The deminished bone formation in the ventromedial area of the shank and the ventrolat eral area of the thigh seems to be due to soft tissue damage and distu rbances in local bone blood supply after the operative approach for co rticotomy.