Atypical femoral fractures: retrospective radiological study of 319 femoral fractures and presentation of clinical cases

Summary There is still no clarity on the etiology and epidemiology of atypical femoral fractures. The purpose is to show, after a radiological review, that the incidence of atypical fractures is higher than that reported in the literature when compared to “typical” fractures that occurred in the same anatomical site. Introduction At present, it is difficult to define the true incidence of atypical fractures associated with bisphosphonate. Our purpose is to show that the incidence of atypical fractures is higher than that reported in the literature when compared to “typical” fractures that occurred in the same anatomical site. Methods The authors analyzed 319 femoral fracture Rxs of patients over 60 who have had access to the PS of Clinical Orthopaedics and Traumatology II of the University of Pisa from January 2011 to February 2013. The atypical fractures have been investigated from clinical point of view, biohumoral exams, densitometry and contralateral femur X-rays, and in one case using SPECT-Tc. Results The total number of femoral fractures was 319. The medial femur fractures were 60 (46 females and 14 males), and the lateral ones were 316 (237 females and 79 males). Subtrochanteric and diaphyseal fractures were 40 (29 females and 11 males). Among these cases, two atypical fracture cases were related to female patients, one was 79 years old and the other was 77. Conclusions The most recent literature reports that the incidence of atypical fractures is 0.6 %. However, taking into consideration only the fracture locations suitable for the identification of atypical fractures, the percentage rises to 5 %. To date, there is still no clarity on the exact etiology of fractures even if it seems to be related to a bone mineral component alteration.