The role of an augmentative plating in the management of femoral subtrochanteric nonunion.

Abstract

Owing to its distinct biomechanical properties, nonunion is common (7-20%) after intramedullary (IM) nailing of subtrochanteric femoral fractures. Unlike diaphyseal nonunion, it is difficult to provide sufficient stability by exchanging nailing alone in subtrochanteric nonunion. This study investigated the clinical outcomes of femoral subtrochanteric nonunion initially treated with an IM nail and subsequently managed with minimally invasive augmentative plate fixation. Nineteen patients were enrolled retrospectively. The mechanisms of initial injury were traffic accidents in 8, falls from a height in seven, and slipping in two patients. Two patients with atypical subtrochanteric femoral fractures without a specific trauma history were further included. All patients underwent IM nailing as the index operation. Nonunion surgery was performed an average of 45.2weeks after the initial surgery. In cases of hardware damage and/or atrophic nonunion, exchange nailing and bone grafting were performed in addition to augmentative plating, as necessary. Conversely, augmentative plating alone was performed in cases of hypertrophic nonunion without any failure of the preexisting IM nail or malalignment. A narrow locking compression plate was fixed after contouring according to the shape of the proximal femur. The mean follow-up period was 36.1months. Bony union was achieved in 18/19 patients (94.7%), at an average of 19.8weeks after nonunion surgery. In the case that did not heal even after exchange nailing, additional plating and bone grafting, further autogenous bone grafting was required after 11months, which healed uneventfully. There were 2 cases of soft tissue irritation over the plate, but no major complications were observed. Additional plate augmentation over a retained IM nail yields satisfactory outcomes in terms of the bony union in subtrochanteric nonunion. Given its expected biomechanical superiority and relatively easy surgical technique, it may be a reasonable option for the management of femoral subtrochanteric nonunion.