The Association of Metal Frame Construct of ESIN and radiographic bone healing of pediatric forearm fractures.

INTRODUCTION: The gold-standard surgical procedure of both-bone forearm shaft fracture repair is elastic stable intramedullary nailing (ESIN). Disadvantages effects of ESIN have suggested to be a consequence of inappropriate surgical techniques, while recommendations are not always followed. The purpose of the study was to analyze the effect of inadequate metal frame construct on impaired fracture healing, refracture and changing alignment.

MATERIALS AND METHODS: It is a population-based study including all consecutive patients, aged less than 16 years, who had been treated for forearm shaft fracture by ESIN during the ten-year period 2009-2018. Altogether 71 patients were included. Non-union, delayed union, and re-fracture during the following 12 months were taken as the main outcome, while inferior metal frame construct of ESIN and the surgical technique characteristics were taken the explanatory factors. Radiographic loss of reduction was a secondary outcome and a change >5° in alignment at any postoperative follow-up exam was recognized.

RESULTS: Two out of 71 fractures (3%) failed to unite, and ossifying operation was needed. Five cases (7%) showed delayed bone healing, but they ossified in five months without any intervention. These seven patients (10%) had been treated more often with larger nails (> 0.7x MCD) (p = 0.027) and by open reduction (p = 0.02), compared with thinner nails and closed reduction, respectively. Two (3%) patients had a second fracture; however, they happened 2 years after the initial injury. Other surgery or fracture related factors didn't associate with impaired ossifying. Regarding the secondary outcome, altogether 24 (35%) of the analyzed 67 patients showed >5° change in alignment during the postoperative follow-up but only one patient had clinically significant instability that required re-reduction. The alignment changed more usually in distal-third fractures, compared with middle or proximal third fractures (p = 0.019).

CONCLUSIONS: ESIN resulted in good radiographic bone healing in the vast majority (90%) of the patients and completely perfect metal frame construct was not required.