Discussion
fractures, metalwork failure
JENSEN, COMPLICATIONS
The present study demonstrates that a second anti-rotational screw can be proven crucial for unstable peri-trochanteric hip fractures, in terms of preventing serious complications, such as cutout, metalwork failure and varus angulation. The operation time was slightly longer though, but not significantly increased and all the radiological parameters for the nail and screw placement were not statistically significantly different. In terms of follow-up, the patient reported outcome scores of the two groups were similar, illuminating that the presence of an anti-rotational screw does not affect the clinical outcome. Concluding that the addition of this additional lag screw is not affecting the other parameters of the intramedullary nail, but indeed contributes to the significant reduction of the severe complications of the unstable peri-trochanteric fractures classified as type 4 and 5 with the Jensen classification (AO 31A2.2 and higher).The finding of the present study are in line with previous similar literature. A randomised clinical trial by Vidyadhara and Rao [The above finding are backed up by some biomechanical studies as well. In a recent biomechanical study by Veerasakul et al. the double lag screw construct demonstrated greater stability when compared with a single lag screw construct [It is reported that peri-trochanteric fractures with significant lateral wall fragmentation can be treated with modern anatomic proximal femoral plates. These allow a reduced fluoroscopic time and intraoperative blood lose, without affecting the recovery and outcomes, when compared with the proximal intramedullary femoral nails [The results of the present study are in line with other previous studies, which emphasize that the correct placement of the basic intertrochanteric heel in terms of position in the "safe zone" and the correct cephalocaudal direction are the most important factors to avoid complications [The presence of the anti-rotational screw does not seem to prevent the posterior slip, but it does seem to make the slip more balanced. In the case of a single lag screw, while the lag screw slides, the head must also slide equally from all sides, if while the lag screw slides the head encounters resistance on one side. That side will stop sliding, so as long as the sliding continues from the opposite side of the head then the head will begin to move in relation to the lag screw with the possibility of leading to a cut-out. Figure Sequential radiographs of a case from group A lead to cutoutSequential radiographs of a case with screw sliding from group BThe present study demonstrates several strengths such as the presence of only the second anti-rotational screw, as the only difference between the two study groups. The study groups were formed randomly but they were similar to many parameters. The limitations of the present study are the relative small number of cases included from a single centre, and the relative small follow up of the cases. Multicentre studies with larger cohorts will help to derive more generalized conclusions. Also the quality of reduction could have affected the results of the study, as it is of paramount importance for uneventful healing. All surgeons achieved good reduction before applying the intramedullary nail though, minimising this possibility.