Lateral condylar fractures of the humerus in children: fixation with partially threaded 4.0-mm AO cancellous screws.

Thirty-seven children with fresh, displaced (more than 2 mm in any direction) fractures of the lateral condyle of the humerus were treated by open reduction and internal fixation with a partially threaded 4.0-mm diameter AO lag screw. They were reviewed at a mean follow-up of 4.8 years. Painless, full-elbow movements were obtained in 36 cases. Delayed union, with loss of 10 degrees of elbow motion, was observed in one case (2.72%). Radiologically, less than 4 degrees of varus deviation, compared with the contralateral side, was found in four cases (10.8%). Mild fishtailing was observed in three cases (8.18%). Nonunion, avascular necrosis or clinically significant premature epiphysial fusion was not observed. Elbow function was excellent, irrespective of minor radiologic abnormalities.