Estimating femoral nail length in bilateral comminuted fractures using fibular and femoral head referencing.

Abstract

Femoral nail length can be estimated preoperatively by several methods, but this usually requires an intact contralateral femur. The aim of this study was to determine an alternative method using fibula and femoral head as references. Digital radiographic views of the lower limbs of 102 healthy volunteers were used to compare femoral medullary length with the sum of fibular length and transverse head diameter. Femoral medullary length and the estimated length were highly correlated (r=0.942, p<0.0001). Paired samples t-testing has produced a high significance (p<0.002). The formula provides a simple and accurate estimation of femoral medullary length, and may be used in nailing, particularly of bilateral comminuted femoral fractures.