Purpose We report the long term outcome of a minimally invasive technique avoiding the risks associated with open reduction and bone grafting in paediatric lateral condyle fracture non-unions.

Methods The Toronto Hospital for Sick Children's radiology database was searched to isolate all those who sustained a lateral condyle elbow fracture and had developed a non-union between the years 1998 and 2008. This identified 16 patients who had undergone percutaneous fixation for the treatment of their non union. Each individuals clinical notes and radiographs were reviewed from presentation to final follow-up.

Results Median age at injury was 5.1 (3.2, 7.2) in the successful and 2.8 (2.1, 4.7) in the unsuccessful groups (p=0.18). 11 patients (68.7%) had been initially managed non-operatively. Median time from injury to non-union diagnosis was 15.7 weeks in the successful, and 225.5 weeks in the unsuccessful group (p=0.039).

Mean time to union post fixation was 16.2 weeks (+/- 6.74) and mean time to surgery was 5.2 weeks (+/- 4.11). Surgery was successful, defined as radiological and clinical union, in 12 of 16 patients (75%). 43.8% had metalwork removal and no cases of avascular necrosis were reported.

Conclusion We have demonstrated this technique to be successful in those non-unions addressed within 16 weeks from initial injury to diagnosis. We had 4 failures, these occurred in patients whose non-unions were diagnosed more than 31 weeks from the time of injury (31; 68; 383; 427 weeks). Each of these failures had been managed non-operatively as part of their primary treatment plan.

Percutaneous fixation is feasible and safe. Patients not achieving union were diagnosed significantly later. There was a trend towards successfully treated patients being younger.