Congenital coxa vara is an infrequent deformity of the femoral neck in children, recognized since 1896 and characterized by a defect which pathologically and roentgenographically is not unlike that seen in aseptic necrosis. Except for its frequent association with a short femur, congenital coxa vara seems to occur entirely apart from other congenital deformities and to possess sufficiently distinguishing characteristics to warrant recognition of it as a separate entity.

The lesion is to be suspected in any child who is born with an obviously short leg or who limps when walking is first attempted. The findings on physical examination suggest a congenital dislocation of the hip, with shortening, high position of the trochanter, and a positive Trendelenburg test. However, there is no telescoping and the femoral head is still palpable beneath the femoral vessels at the groin. The roentgenogram will confirm the diagnosis if the lesion is not mistaken for an ununited fracture of the femoral head, a rare condition in children.

The aim of treatment is to promote ossification in the neck of the femur and to correct any deformity already present. Subtrochanteric osteotomy with wide abduction of the distal part of the limb will correct the coxa vara, and conversion of the sheering strain across the defect into a compression force along the axis of the neck promotes complete ossification in a high proportion of cases.

Adolescent and adult patients with untreated lesions exhibit what amounts to nonunion of the femoral neck. Of the reconstructions available for such lesions, the Brackett operation is particularly suitable because of the high percentage of viable heads found at operation.

The series of fifteen cases reported here is fairly representative and purposely includes four examples of unusual coxa vara (Cases 8, 10, 14, and 15), from which it would seem advisable to differentiate the specific lesion defined in this paper.

It can be said, then, that congenital coxa vara as herein defined is not a proved congenital deformity. The frequent association of this lesion with a short femur is probably due to a common etiological factor, possibly avascular necrosis. Coxa vara associated with multiple congenital deformities is not the same lesion as that with which this paper is concerned. Subtrochanteric osteotomy at about six to eight years of age, with wide abduction of the distal part of the limb, is the treatment of choice.