[Femoral lengthening by transverse diaphyseal osteotomy. Experimental study in the dog]

Previous work has shown that extensive areas of bone necrosis developed after Z-osteotomies of the femoral shaft. A study was made on 11 dogs to compare the effects of a transverse osteotomy followed by immediate lengthening, stabilisation by plates and bone grafting. The bone vitality was studied at 8 and 16 weeks by histological sections and angiography. Attention was focussed on the area of lengthening and the bone ends. The results showed the superiority of transverse osteotomy over Z-osteotomy. Bone necrosis diminished at the 16 th week. In the area of lengthening, the vascularity of the grafts was satisfactory. In contrast, the tendons of the Z-osteotomy showed constant necrosis.