Lateral humeral condyle fracture

Last revised by Joshua Yap on 4 May 2024

Lateral humeral condyle fractures also referred to simply as lateral condyle fractures (in the appropriate context), are relatively common elbow fractures that predominantly occur in children. They may be subtle but are hugely important to diagnose promptly because if they are missed, they tend to migrate dorsally and can have significant morbidity without treatment. 

Lateral humeral condyle fractures are usually simply termed lateral condyle fractures. They are a completely different entity to a lateral epicondyle avulsion fracture where the ossification center is avulsed.

They represent ~13% (range 5-20%) of elbow fractures in children and are the second most common pediatric elbow fractures after supracondylar fractures.

They occur in school-age children, with a peak at 6 years 4.

These occur either after a fall onto an outstretched hand.

Two theories exist regarding the mechanism of injury: push-off and pull-off theories 2

  • push-off theory: there is a direct force upwards and outwards causing the radial head to impact the capitellum 2

  • pull-off theory: the lateral condyle avulses due to the extensor carpi radialis longus and brevis creating a varus stress on a supinated forearm 2,4,5

The fracture can be underestimated on plain films and may be seen as a small sliver of bone adjacent to the proximal border of the capitellum. The fracture through the lateral condyle will have a large cartilaginous component as well as a small osseous portion.

The best view to see the lateral condyle fracture is an internal oblique and this should always be performed when a lateral condyle fracture has been diagnosed. This is done by pronating the arm, however, it is important to be aware that by placing the arm in pronation the fracture may be further displaced 14

The displacement of the distal fracture component is best demonstrated on the internal oblique view. This is because the fracture usually lies posterolaterally 14.

The Milch and Weiss classifications have been used for these fractures. The Weiss classification uses the degree of displacement of the fracture and is a more relevant measure of severity.

CT may be helpful when assessing a complex fracture, but is usually not required in a lateral condyle fracture. All the required information is usually present on the plain radiograph.

MRI will delineate the whole fracture (cartilage and bone) and may help to determine any additional injury. However, whilst MRI does not change initial management it may be useful in the pre-operative planning in non-union 2.

When describing a lateral condyle fracture, it is important to comment about:

  • size of the osseous component

  • displacement (in mm) on the internal oblique view

  • associated elbow joint effusion

  • any additional injury

The majority of these fractures are not displaced >2 mm (33-69%) 2 and can be treated conservatively. Non-operative management is indicated when the fracture is displaced <2 mm and when the medial cartilaginous hinge is intact. It involves long-arm casting for approximately 4-6 weeks 2,14.

If there is >2 mm displacement on the internal oblique view, the risk of further displacement is high and operative management is recommended. Operative management in displaced fractures takes the form of either closed reduction and percutaneous pinning or open reduction and internal fixation with a cannulated screw and washer 2,14. When open reduction is performed it is important to avoid posterior and distal dissection as this may interrupt blood supply and lead to osteonecrosis 2.

The following complications may occur as a result of either non-operative or operative management 2,14:

  • stiffness

  • delayed union

  • non-union

  • fracture displacement

  • cubitus valgus (>10%) with tardy ulnar nerve palsy, cubitus varus (>20%)

  • osteonecrosis

  • fishtail deformity

  • lateral overgrowth

  • growth arrest (uncommon)

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