The Proximal Tibial Physeal Changes in the Skeletally Immature Rabbits after the physeal Distraction / 대한정형외과학회잡지

Physeal distraction is used for limb lengthening or correction of deformities in skeletally immature patients. But the effect of distraction on the physis is uncertain. The young rabbits were arranged into five groups according to the slow distraction rates: Group I (no distraction), Group II (distraction rate of 0.25mm per day), Group III (distraction rate of 0.5mm per day), Group IV (distraction rate of 0.75 mm per day), Group V (distraction rate of 1mm per day). The tibial length, size of proliferating zone, microscopic findings of physis immunostained with bromodeoxyuridine, and physeal response to physeal distraction on each group were studied. The results were as follows. 1. There was an increase in bone length on the distracted side (1.8 to 4.2mm). 2. There was an irregular increase in the thickness of the distracted physis. 3. There was an abnormal accumulation of hypertrophic chondrocytes in hypertrophic zone in distracted physis. 4. There was no evidence of anomalous cell proliferation, in the resting, proliferating and hypertrophic zones. These results conclude that the physeal distraction does not stimulate cell proliferation in the physis, even when it is seen to be thickened after the chondrodiatasis.

Spontaneous Correction of the Angular Deformity after Femoral Shaft Fractures in Children: Preliminery Report / 대한정형외과학회잡지

We reviewed 14 children with unilateral fractures of femoral shaft who had an angular deformity after union of 10° to 25°. At an average follow-up of 32 months(15 to 65), we measured remodelling of the proximal physis, the distal physis and the femoral shaft. The average correction was 83% of the initial deformity and there was no relation between the remodelling rate and degrees of malunion. Of the correction of angulation, only 27% had occurred at the fracture site and 73% at physis. The ability of physis to remodel better than that of fracture site. In children under 13 years of age, malunion as much as 25° in flexion deformity will remodel enough to get normal alignment of the joint surfaces.