[Experimental research on DNA content of the cell nuclei in the lengthening side physis after near metaphyseal osteotomy].

In order to study the influence of the diaphyseal distraction upon further growth of the lengthening side physis. We applied the modified Ilizarov-type external fixator to the left tibiae of thirty-five goats. Diaphyseal corticotomies were performed, and distraction was carried out by using the Ilizarov's method. A group of 5 goats each was sacrificed 7, 14, 21, 28, 35, 49 and 63 days postoperatively. Specimens of the lengthening side epiphysis for DNA quantitation VIDAS were decalcified with 5% EDTA and Feulgen stained. There was little influence subject to the Tension-Stress in lengthening side epiphysis as the mean DNA content corroborated its cell nuclei in 3C-4C region. The hypertrophic layer of physis on the lengthened side was thicker than that on the control side while the lines of epiphysis in roentgenography was still observable after removal of external fixator at 35 days post lengthening. Although lengthening by metaphyeal osteotomy was safe, the damage to the physis by Tension-Stress should be minimized.