Radiologic healing of lateral femoral wall fragments after intramedullary nail fixation for A3.3 intertrochanteric fractures

Intramedullary nail fixation is a useful treatment option for A3 intertrochanteric fractures. Occasionally, we have encountered displaced lateral femoral wall (LFW) fragment during surgery with intramedullary nail system. We investigated the postoperative spontaneous reduction of displaced LFW fragments without further fixation and the factors that affected the spontaneous reduction of displaced LFW fragments. Forty-four patients with A3.3 intertrochanteric fracture were treated by surgery using intramedullary nails (PFNA; Synthes, Paoli) between March 2007 and December 2012. All patients had a minimum follow-up period of 12 months. We calculated the amount of spontaneous reduction of the displaced LFW fragments from immediate postoperative and last follow-up anteroposterior radiographs. We measured the tilting angle of the LFW fragment, tip-apex distance (TAD), and telescoping of the blade, and evaluated the quality of postoperative reduction. Twenty-five of the 44 patients had displaced LFW fragments, and the average amount of spontaneous reduction of the displaced LFW fragment was 4.8 mm with statistical significance (p = 0.005). The average tilting angle of all patients was -4.97A degrees, telescoping was 6.83 mm, and TAD was 19.77 mm. Twenty-one patients had good quality of reduction, 21 had acceptable quality, and 2 had poor quality. Multivariate logistic regression analysis for these factors indicated that tilting angle was the only significant factor related to spontaneous reduction of a displaced LFW fragment (p = 0.007, odds ratio = 1.336). In intramedullary nailing of A3.3 intertrochanteric fractures, the displaced LFW fragments tend to reduce spontaneously without any additional fixation during the postoperative period. We conclude that no additional fixation is needed for the displaced LFW fragment after surgery with intramedullary nail.