Cortical erosion after elastic stable intramedullary nail fixation for pediatric long bone fractures: Case series according to the site.

BACKGROUND: Elastic stable intramedullary nail (ESIN) is widely used for treatment of long bone fractures in children. However, migration of the nail or cortical bone erosion in children has been reported. This study was conducted to investigate the incidence of cortical erosion according to the site and cortical erosion type.

MATERIALS AND METHODS: A total of 221 normally developing children (223 fractures) who were treated with ESIN for fractures of the long bones without cortical breakage at immediate postoperative radiography and with the ESIN in position for more than 6 months were included. Two pediatric orthopaedic surgeons reviewed all the radiographs. Cortical bone erosion was defined when the two investigators agreed that there was cortical breakage by the ESIN.

RESULTS: Penetration of nails through the bone cortex was observed in 25 patients (11.2%). Fifteen patients (6.7%) showed cortical erosion at the diaphysis and ten patients (4.5%) showed protrusion of the tip of the ESIN at the metaphysis-diaphysis junction. The average time for hardware removal in patients with cortical erosion was 14.2 months.

CONCLUSION: Cortical bone erosion by ESIN could occur in pediatric long bones without any iatrogenic problem or disease related to the bony structure. Erosion at diaphysis was more common than at metaphysis-diaphysis junction. Cortical erosion should be considered in children who retain their ESIN for a long time.