Lopes-Coutinho L, et al. - This study was conducted to investigate which of these two indexes is better in predicting failure of pertrochanteric fracture fixation. A retrospective study was designed to focus on pertrochanteric fractures operated in the institution between 2010–2013. Researchers conducted radiographic assessment of both indexes. They obtained demographic information, as well as several variables with recognized influence on the rate of failure. They applied logistic regression analysis to identify variables independently associated with fixation failure. Researchers operated a total of 463 pertrochanteric fractures during this time period. The results indicate that both the traditional TAD and the new calcar tip-to-apex (calTAD) have shown to be relevant indexes and independently predictive of the likelihood of failure of pertrochanteric fracture fixation. The optimal threshold for the traditional TAD was found to be lower (<20 mm) than the traditional cutoff (<25 mm). The calTAD was not confirmed to be superior to the traditional TAD. The authors argue, from the surgical practice point of view, that the ideal position of the screw is the central region of the femoral head (minimal traditional TAD). It must be infero-central in case of deviation, in order to maintain a low calTAD therefore reducing the risk of fixation failure.