[The value of ultrasonography in monitoring limb lengthening].

The authors attempted to assess the value of ultrasound for monitoring of the new bone formation at the site of distraction in patients undergoing limb lengthening after Bastiani. Twenty patients were assessed; 12 cases of femur lengthening and 8 cases of tibia lengthening. It was found, that ultrasound allowed to detect the new bone formation visible as hyperechogenic foci as soon as 4 to 14 days postoperatively, while regular radiology showed this only 4 to 8 weeks after operation. Detection of the new bone formation at the site of lengthening permits, in authors opinion, to choose an optimal onset of distraction and its pace according to the speed of bone formation. Regular ultrasound monitoring prevents premature bone union or disintegration of the newly generated bone in case of to slow or to fast distraction respectively. In two cases sonography early demonstrated cystic changes at the location of distraction. It also permits detection of an axial displacement of the fragments of bone in every case.