SciELO - Scientific Electronic Library Online

vol.13 issue1Search for variants of the LRP4 gene in women with high bone mass and in patients with Chiari type I malformationPathophysiology of osteoporosis in chronic inflammatory joint diseases author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google


Revista de Osteoporosis y Metabolismo Mineral

On-line version ISSN 2173-2345Print version ISSN 1889-836X


ARIAS-BLANCO, A et al. The cut-out phenomenon in intertrochanteric femur fracture: analysis using a finite element model. Rev Osteoporos Metab Miner [online]. 2021, vol.13, n.1, pp.21-31.  Epub May 17, 2021. ISSN 2173-2345.


This work aimed to analyze the cut-out phenomenon, which involves oblique displacements and/or rotations of the femoral head around the cephalic component of the intramedullary nail. The analysis was carried out using finite element numerical models. This technique seeks to understand the failure of this type of fixation and establish what positioning of the system favors or prevents failure due to cut-out.

Material and methods

The study was carried out on a numerical model of the proximal limb of an artificial femur and an intramedullary nail type PFNA (proximal femoral nail anti-rotation). In the numerical model, the position of the intramedullary nail was varied in the anterior/posterior and superior/inferior directions to analyze the influence of the position on the cut-out phenomenon. Stresses in critical areas and torque on the nail under normal position loading were analyzed.


The most critical position was the one in which the intramedullary nail is placed in the superior position, due to the high compressions that appear in the trabecular bone of the femoral head. The centered position of the nail decreased the risk of bone damage and the torque that the intramedullary nail has to support.


This type of model allows us to simulate the influence of the nail position and obtain variables that are otherwise difficult to analyze. Although it is a simple model with static load, it confirms that a centered position of the intramedullary nail reduces the risk of cut-out.

Keywords : femur; hip fracture; extracapsular fracture; intramedullary nail; cut-out; finite element model.

        · abstract in Spanish     · text in English | Spanish     · English ( pdf ) | Spanish ( pdf )