The Von Laer classification, also known as the Laer classification, is used to grade the severity and the need for further diagnostic evaluation and surgical correction of pediatric supracondylar humerus fractures, based on their clinical and radiological presentation.
Classification
Von Laer's classification divides supracondylar humerus fractures into four types.
Type I
supracondylar humerus fracture without dislocation (stable)
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positive fat pad sign, no displacement of the capitellum
sometimes the fracture only becomes evident through periosteal reaction days after the initial trauma
usually presents with light swelling and reduced mobility due to pain
no surgical correction is required, only conservative management with cast application
Type II
supracondylar humerus fracture with dislocation in the sagittal plane (sometimes unstable).
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positive fat pad sign, dorsal displacement of the distal fragment/capitellum
moderate-to-severe swelling and pain
surgical correction required if dorsal displacement >30°
follow-up X-ray in 3-5 days
Type III
supracondylar humerus fracture with dislocation in every plane and rotation deformity (unstable)
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positive fat pad sign, displacement and rotation of the distal fragment/capitellum
further evaluation with Doppler ultrasound to exclude vascular injury is recommended
severe swelling and pain, ecchymosis, visible deformity
surgical correction via intramedullary nailing, Kirschner wire or external fixation required
Type IV
supracondylar humerus fracture with dislocation in every plane, rotation deformity and no contact between fragments (unstable)
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positive fat pad sign, displacement and rotation of the distal fragment/capitellum
further evaluation with Doppler ultrasound to exclude vascular injury is recommended
severe swelling and pain, ecchymosis. If dislocation is severe, S-shaped deformity may be present.
surgical correction via intramedullary nailing, Kirschner wire or external fixation required