Lateral humeral condylar fractures are challenging to treat. The diagnosis requires a careful assessment of their epiphyseal extension, which may indicate the propensity for displacement. Displaced fractures require operative management, but the treatment for nondisplaced or minimally displaced lateral condylar fractures remains controversial. This study attempted to retrospectively review patient charts at two institutions with differing treatment philosophies to compare these methods. At one institution, nondisplaced fractures were immobilized, where displaced fractures were treated by surgery. At the second institution, all lateral condylar fractures were treated surgically, whether displaced or nondisplaced with Kirschner wire fixation. Retrospective review revealed 57 children at the first institution and 40 at the second. Demographics between the institutions were fairly similar.
Fractures were classified by an independent observer and classified according to the Milch system. In addition, maximum displacement was measured on the anterior or posterior lateral radiographs. Fractures with less than 2 mm of displacement were considered nondisplaced or minimally displaced. This number of fractures totaled 30. In contrast, fractures greater than 2 mm of displacement were considered displaced, and this lead to a total of 67 fractures. Patient follow-up averaged one year, and outcome was based on follow-up visit including range of motion and x-rays. In addition, the x-rays were scrutinized for bone healing, avascular necrosis, overgrowth, malunion, nonunion, fishtail deformity, or lateral bony spurs.
The 30 nondisplaced or minimally displaced fractures were treated with casting alone in 17 and surgically in 13. The 13 surgical treated fractures were treated with a variety of percutaneous techniques. The pins were placed in different configurations. The 67 displaced fractures were all treated with operative management. Again, variation in technique in fracture fixation existed amongst the patients. Of the 30 nondisplaced or minimally displaced fractures, 17 underwent initial nonoperative treatment. Five had additional displacement. Radiographic follow-up showed evidence of two malunions and two nonunions. Both nonunions required additional surgery and eventually healed. In this group, loss of flexion was minimal at 5 degrees, and loss of extension was relatively small at 7 degrees. Two x-rays showed a fishtail deformity at follow-up and one x-ray showed evidence of growth plate injury. Thirteen of the 30 nondisplaced or minimally displaced fractures underwent operative treatment. Two patients lost reduction secondary to poor surgical technique and malunion developed. There were no incidences of a nonunion or infection. In this group, loss of flexion was 3 degrees and loss of extension 8 degrees on average. Two fishtail deformities were evident on radiographic x-ray and one growth plate injury.
The treatment of displaced fractures was remarkably different. Ten fractures were deemed to be displaced on the x-rays, although they were initially classified as nondisplaced or minimally displaced. These consistently resulted in malunion or nonunion. The remaining 57 displaced fractures underwent initial operative treatment. Displacement occurred in four elbows, and five malunions also occurred. No nonunions were noted. Fewer malunions were noted if at least two Kirschner wires passed the opposite cortex. There were instances of superficial infections related to leaving the pins in the percutaneous position. Loss of flexion averaged 5 degrees and loss of extension averaged 11 degrees.
Although this study has the limitation of being retrospective, it has certain merit. Previous authors have highlighted the role of the cartilage hinge in fracture stability. Propagation of the fracture across the cartilage hinge increased the incidence of displacement. Visualization of the cartilage can be obtained by arthrography, ultrasonography or magnetic resonance imaging. One option is to obtain advanced imaging on all lateral condylar fractures, although this is not cost effective or likely. Another option is physician vigilance to the possibility of migration and, therefore, earlier surgical intervention. Operative treatment should be recommended in displaced fractures or if one can determine whether the fracture line disrupts the cartilaginous hinge. Careful monitoring following cast application is necessary to diagnose early fracture displacement and allow for reduction and pinning. In contrast, displaced fractures are generally treated with closed or open reduction to allow for realignment of the joint surfaces and growth plate. Two or three Kirschner wires are added to allow for additional rotational control. Penetration of the ossific nucleus of the capitellum did not result in a higher incidence of complications and, therefore, can be performed if the metaphyseal fragment is small. In conclusion, the treating physician should have a low threshold for consideration of percutaneous or open reduction in those fractures that demonstrate the propensity for displacement.
J Pediatr Orthop 24:385-391, 2004.