The Butterfly Fragment in Wedge-Shaped Femoral Shaft Fracture: Comparison of Two Different Surgical Methods

Abstract

Objective: Our study compared the results of wedge-shaped femoral shaft fracture following intramedullary (IM) nailing with or without fixation of the third fragment.

Methods: We retrospectively reviewed patients presenting with femoral shaft fracture with AO/OTA type 32-B from 2011 to 2016. Patients were divided into two groups: closed reduction without touching the third fragment and open reduction with fixation of the third fragment. The fragment ratio, fragment length, nail size, dynamization or not, mRUST scores, union rate, and union time were compared between the two groups. Risk factors of non-union were also investigated, including sex, age, fracture pattern, fracture location, dynamization, nail size, fragment ratio, fragment size, and postoperative fragment displacement.

Results: A total of 80 patients met inclusion criteria, 20 patients with wedge-shaped shaft femoral fracture were managed with IM nailing and open reduction with fixation of the third fragment. Sixty patients were treated with IM nail without touching the third fragment. The union rate for the fixation and non-fixation groups were 60.0% and 81.7%, respectively. The mean union time for the fixation group was 19 months vs 14 months for the non-fixation group. Multi-regression analysis showed larger nail size (odds ratio: 2.26) and fixation of the third fragment (odds ratio: 0.18) influenced fracture healing.

Conclusions: Fixation of the third fragment in wedge-shaped shaft femoral fracture results in a longer union time and lower union rate. In the management of femoral fracture with a third fragment, a larger nail size is recommended and fixation should be performed in a closed manner. Fixation of the fragment may achieve better fracture reduction. However, disruption of the vasculature and surrounding structures may further result in nonunion of the fracture site.

Keywords: femoral shaft fracture; intramedullary nailing; third fragment; union rate; union ratio.