Die Knochenneubildung bei der Kallus- und der Epiphysendistraktion

Abstract

X-rays were reviewed after callus distractions (50 cases) and distraction epiphysiolysis (10 cases) in 45 patients. With the aid of a computerized digitization system for analogue films, the relative x-ray density of the distraction area was determined in the medial, lateral, ventral and dorsal surface areas, and in the median line of the callus tissue. Bone formation became evident within 21.7 +/- 3.7 days post-distraction in the thigh and 25.4 +/- 4.9 days in the shank. The lowest density values were found at the end of the distraction phase followed by a continual increase in x-ray density in the fixation phase. There was a significant decrease in callus x-ray density in the shank from lateral to medial and from dorsal to ventral, and in the thigh from medial to lateral and from dorsal to ventral. When the corticotomized callus distraction is compared to the distraction epiphysiolysis without corticotomy it becomes apparent that the differences between lateral-medial x-ray densities and dorsal-ventral x-ray densities were significantly greater in the group with callus distraction. The deminished bone formation in the ventromedial area of the shank and the ventrolateral area of the thigh seems to be due to soft tissue damage and disturbances in local bone blood supply after the operative approach for corticotomy.