CLASSIFICATION AND TREATMENT OF FEMORAL NECK NONUNIONS IN YOUNG PATIENTS

Abstract

Retrospective data over an eight-year period was collected on twenty-four young patients with non-union of a femoral neck fracture who were followed to union. The cause of each nonunion was identified and a classification of the nonunions was established in order clarify treatment options. Patients were treated by a single surgeon. The treatment protocol was based on the classification of the femoral neck nonunion. There were no nonunions in the treated patients; however two patients who showed signs of avascular necrosis prior to treatment ultimately developed AVN.

Femoral neck nonunion occurs in 20–30% of displaced femoral neck fractures. If the femoral head is viable, the treatment goal is femoral neck union to maintain it. Treatment options depend on the cause of nonunion. To clarify treatment options, a classification of nonunions was developed.

The treatment regime developed was based on the type of nonunion. We believe that subclassification of the femoral nonunion improves the selection of treatment options. This classification-based treatment does not reduce the incidence of avascular necrosis, but does seem to guarantee union while permitting excellent function of the hip joint

A classification system based on the cause of the non-union clarifies treatment options to maintain the femoral head and produce union of the femoral neck.

Based on the analysis a classification proposal relating to treatment was developed. In the original treatment group there were no nonunions but two cases of ultimate avascular necrosis— both showed signs of AVN on bone scan prior to treatment.

Classifications:

Type I – Inadequate fixation or non-anatomic reduction (eight patients)

Type II – Loss of fixation with displacement (fourteen patients)

Type III (Rare) – Fibrous nonunion with no displacement and intact fixation (two patients)

Twenty-four patients were treated by one surgeon and followed to union over eight years. The results were examined retrospectively to categorize cause of non-union and treatment protocol. A classification system that describes classes of nonunions and treatment for each type was developed.