Bioabsorbable Pin Fixation in Late Presenting Pediatric Radial Neck Fractures

Current treatment algorithms for pediatric radial neck fractures reserve open treatment for severe residual angulation. There is a paucity of literature guiding treatment for delayed presentation resulting in malunion. Bioabsorbable pins have been used successfully for many other fracture types in the upper extremity. The purpose of this study is to determine whether open reduction, bioabsorbable fixation with an osteotomy when necessary is a reasonable treatment option in delayed pediatric radial neck fractures by assessing pain, range of motion, functional, and radiographic outcomes.

Radial neck fractures were evaluated in 7 children, 4 to 12 years old, with delayed initial presentation averaging 20 days. Patients presented with an average angular deformity of 63 degrees and translational deformity of 57% (6.1 mm) in the AP plane, all with painful and reduced range of motion. Patients underwent open reduction and fixation with Self-Reinforced Poly-L-Lactic Acid pins after failed closed reduction. Four patients required formal osteotomies. Postoperative follow-up averaged 9.2 months and consisted of radiographic and clinical evaluation with Wong-Baker FACES Visual Analog scale and the Mayo Elbow Performance (MEP) score.

Final radiographs demonstrate an improvement in angular deformity by 56 degrees and translational deformity by 51%. Final clinical outcomes demonstrated significantly improved pain-free range of motion with excellent MEP scores in 6 of the 7 patients. One patient developed a radioulnar synostosis, subsequently undergoing synostosis excision with a final MEP score of 80/100. There was no evidence of physeal closure or avascular necrosis and no cases requiring hardware removal or complicated by local inflammatory reactions.

This small series shows encouraging results in the treatment of pediatric radial neck fractures with delayed presentation using open reduction, bioabsorbable fixation, and when necessary an osteotomy. Bioabsorbable fixation may eliminate issues surrounding subsequent hardware removal and pin-site infections. Despite these encouraging results, radioulnar synostosis after open surgery is still a concern.

Level IV-case series.