Proximal femoral epiphysiolysis in the neonate.

Seven neonates with eight proximal femoral epiphysiolyses were reviewed. Pain elicited by leg motion was the common diagnostic finding in all. Radiography showed lateralization of the shaft similar to congenital hip dysplasia. However, the acetabular index was normal in all but one child. Arthrography confirmed the diagnosis, showing a located proximal femoral epiphysis and a laterally displaced, externally rotated proximal metaphysis. Treatment usually consisted of traction followed by abduction splinting. The long-term results were excellent in six fractures. Growth complications included angular deformation (bowing) in one patient and coxa vara due to localized premature epiphysiodesis in one patient. Duplication of the lesion in stillborn cadavers showed that the fracture was usually a type 1 physeal injury traversing the entire physis beneath both the capital femur and the greater trochanter. The periosteal sleeve was intact posteriorly and still attached to the proximal physis. However, in two instances there was comminution (rather than crushing) of the epiphysis, physis, and metaphysis medially, which might explain the residual varus deformation and premature growth arrest seen infrequently as complications of this particular proximal femoral injury. An experimental animal model also duplicated these morphologic observations.