THE TIP-APEX DISTANCE: THE CURRENT, VALIDITY AND INNOVATIONS.

Abstract

Introduction: Surgical treatment of intertrochanteric fractures involves multiple post-surgical complications due to several factors. The tip-apex distance or "TAD" is one of the main predictors of femoral screw displacement or "cutout". Objective: perform a bibliographic review of the "TAD" in the most current scientific studies. Materials and methods: Descriptive study of bibliographic searches in scientific sites such as Scielo, Elsevier, Pubmed, Medline and national and international virtual libraries. Results: Intertrochanteric fractures account for 50% of all fractures of the proximal femur, higher incidence in women (2:1 to 8:1) and people over 65 years, post-surgical complications account for 17%, screw displacement or "cutout" is described as the most common complication. The TAD has been used since 1995; migration of the sliding screw in the femoral head is observed even in patients with a cut out of less than 25 mm, due to the implication of factors (associated with the implant, poor positioning of the sliding screw and poor bone quality), giving an optimal threshold of cut out lower (<20 mm) than the traditional cut out (<25 mm); for every millimeter that the cut out increases, the risk of cut out increases approximately 1.1. TAD has a significantly higher specificity than CalTAD y TAD + CalTAD (59.1 vs 49.2%, p <0.001; 59.1 vs 54.1%, p <0,001). Conclusions: The "TAD", is still the biggest predictor of "cut out" at present even above the new predictors.