The Effect of Valgus Reduction on the Position of the Blade of the Proximal Femoral Nail Antirotation in Intertrochanteric Hip Fractures

Background: The purpose of this study was to evaluate the quantitative association between the degree of reduction and the position of the blade of the proximal femoral nail antirotation (PFNA) in intertrochanteric hip fractures. Methods: From March 2009 to April 2015, 530 patients treated with PFNA for intertrochanteric hip fractures were retrospectively reviewed. Patients were divided into a valgus reduced group (group 1) and a non-valgus reduced group (group 2), and the "valgus reduced" was defined as valgus reduction over 5 degrees. We compared the calcar referenced tip-apex distance (calTAD) and the area between the blade of PFNA and the medial cortex of the femoral neck between the two groups. Results: The calTAD was measured as 22.5 +/- 4.1 mm in group 1 and 24.8 +/- 3.8 mm in group 2 (p < 0.05). The area between the blade and the medial femoral neck was measured as 135.5 +/- 49.8 mm(2) in group 1 and 145.1 +/- 54.8 mm(2) in group 2 (p = 0.074). The area corrected for the length difference in the femoral neck was 0.55 +/- 0.16 in group 1 and 0.79 +/- 0.19 in group 2 (p < 0.05). Conclusions: Valgus reduction resulted in less calTAD and inferior position of the blade at the femoral neck in the treatment of intertrochanteric hip fractures with PFNA.