Distraction of the growth plate. Experiments in pigs and sheep

Distraction of the growth plate of the distal radius was performed on 15 pigs and 10 sheep of growing age. The separation of the plate from the metaphysis occurred within 4-6 days after the operation. The distraction rate was 1-1.5 mm/day and was continued for 1-3 weeks. Consolidation of the separation area occurred within 6 weeks. Oxytetracycline bone labelling showed that the ossification developed toward the centre of the separation line from the metaphysis and from the inner layer of the periosteum as well as from the physeal side. The growth of the bone continued after the distraction procedure and in most cases the growth plate was open when examined radiologically after the distraction.