Treatment of lower limb deformities and limb-length discrepancies with the external fixator in Ollier's disease

Background In this study, we addressed two questions on the treatment for Ollier's disease: (1) how much callus formation occurs when an osteotomy is performed intralesionally and (2) how is the stability of the wires and half-pins that are inserted intralesionally. Methods Four children with Ollier's disease underwent treatment of 12 lower limb segments using distraction osteogenesis until completion of their growth. All osteotomies were performed at the centers of the deformities, resulting in a total of seven osteotomies performed intralesionally. Results Full correction of the deformity and full restoration of length were achieved in all cases, but a residual limb-length discrepancy of <10 mm remained. The mean external fixation index in the intralesional distraction osteogenesis group was 39.7 days/cm versus 30.8 days/cm in the extralesional distraction osteogenesis group. Conversion from abnormal cartilage to normal regenerate bone was seen in only one segment. Although approximately two-thirds of the wires and half-pins were inserted intralesionally, in all but one case (in which an iatrogenic fracture occurred) the wires and half-pins were well stabilized throughout the external fixation period. Conclusions Although deformity and limb-length discrepancies due to Ollier's disease were successfully resolved by distraction osteogenesis, enchondroma may arise in distracted calluses when osteotomized intralesionally. However, the stability of the external fixator was sufficient to lengthen limbs and correct deformities even when wires and half-pins were inserted intralesionally.