AND INTRAOPERATIVE FLUOROSCOPY TIME BETWEEN INTRAMEDULLARY AND EXTRAMEDULLARY FIXATION IN TROCHANTERIC FRACTURES TREATMENT

Background/Aim. There are cephalomedullary and extramedullary methods of trochanteric fractures internal fixation. Third generation Gamma Nail (GN) is a gold standard in these fractures surgery. Selfdynamisable Internal Fixator (SIF) is an extramedullary implant for trochanteric fractures treatment. The aim of this study was to compare these two methods regarding operation time and intraoperative fluoroscopy time. Methods. Eighty-nine patients with surgical treatment of a trochanteric fracture were included in this study. There were two groups of patients – GN group (43 patients) and SIF group (46 patients). Results. Average operation times were 67.5 min (GN group) and 56.0 min (SIF group). Average intraoperative fluoroscopy times were 84.8 s (GN group) and 36.7 s (SIF group). The difference between the groups was statistically significant for both followed parameters (p<0,05). The correlation between operation time and intraoperative fluoroscopy time was confirmed in SIF group (p<0,05; r=0,405), while it wasn’t confirmed in GN group (p>0,05). Conclusion. The number of daily surgical interventions planed could depend on the type of trochanteric fracture internal fixation (intramedullary od extramedullary). Additional analysis including radiation dose assessment is desirable to clarify if shorter intraoperative fluoroscopy time in SIF method can have the influence in intraoperative x-ray protection clothing. There is higher variability in GN method than in SIF method regarding duration and type of repeated surgical maneuvers followed by x-ray checks. If there is the need to activate dynamization in long femoral axis after initially static fixation in that axis, the SIF method provides its spontaneous activation several weeks after surgery, without the need for additional surgery and for additional intraoperative fluoroscopy too.

Background/Aim. There are cephalomedullary and extramedullary methods of trochanteric fractures internal fixation. Third generation Gamma Nail (GN) is a gold standard in these fractures surgery. Selfdynamisable Internal Fixator (SIF) is an extramedullary implant for trochanteric fractures treatment. The aim of this study was to compare these two methods regarding operation time and intraoperative fluoroscopy time.
Methods. Eighty-nine patients with surgical treatment of a trochanteric fracture were included in this study. There were two groups of patients -GN group (43 patients) and SIF group (46 patients). Results. Average operation times were 67.5 min (GN group) and 56.0 min (SIF group). Average intraoperative fluoroscopy times were 84.8 s (GN group) and 36.7 s (SIF group). The difference between the groups was statistically significant for both followed parameters (p<0,05). The correlation between operation time and intraoperative fluoroscopy time was confirmed in SIF group (p<0,05; r=0,405), while it wasn't confirmed in GN group (p>0,05). Conclusion. The number of daily surgical interventions planed could depend on the type of trochanteric fracture internal fixation (intramedullary od extramedullary). Additional analysis including radiation dose assessment is desirable to clarify if shorter intraoperative fluoroscopy time in SIF method can have the influence in intraoperative x-ray protection clothing. There is higher variability in GN method than in SIF method regarding duration and type of repeated surgical maneuvers followed by x-ray checks. If there is the need to activate dynamization in long femoral axis after initially static fixation in that axis, the SIF method provides its spontaneous activation several weeks after surgery, without the need for additional surgery and for additional intraoperative fluoroscopy too.  Gold standard in trochanteric fractures internal fixation is third generation of Gamma Nail, as an intramedullary method with a cannulated lag screw 6,7,8,9 . Trochanteric fractures with pertrochanteric component (fracture line extending in lower-medial direction from the greater trochanter) require the use of lag screws 6,9 . Selfdynamisable Internal Fixator (SIF) is an extramedullary implant being in routine use at many centers, predominantly for femoral fractures fixation. There are different types of SIF implants. The type having a "trochanteric unit" includes the use of lag screws for femoral neck and head 10, 11, 12, 13 . The "trochanteric unit" is available in two modesthe mode with multiple thinner non-cannulated lag screws and the mode with one wider cannulated lag screw.
The aim of this study was to compare an intramedullary and an extramedullary method of pertrochanteric fractures internal fixationthird generation Gamma Nail and Selfdynamisable Internal Fixator with two non-cannulated lag screws, regarding operation time and intraoperative fluoroscopy time. There were 67% female and 33% male patients. The fixation method used (intramedullary or extramedullary) depended on the surgeon's choice to the method he was more familiar.

Methods
Gamma Nail used in this study was third generation short Gamma Nail. The type of Selfdynamisable Internal Fixator used had "trochanteric unit" with three holes for noncannulated lag screws. In all cases with this implant, proximal fracture fragment was fixed by two lag screws. Three lag screws can be used in patients with very wide femoral neck and there was no such case in this study. When using just two lag screws, triangular configuration of these holes gives an opportunity for surgeon to have the choice for more Bivariate correlation, by Spearman's correlation coefficient, was analyzed between followed parameters.

Results
In relation to SIF group, average operation time and intraoperative fluoroscopy time were significantly higher in GN group (p<0,05) ( Table 1 The correlation between operation time and intraoperative fluoroscopy time was confirmed in SIF group (p<0,05) and this correlation was low positive (0,3<r<0,5). The correlation was not confirmed in GN group (p>0,05) ( Table 2). thus Selfdynamisable Internal Fixator can be considered as an "intelligent implant" that "recognize" the need for dynamization in the long femoral axis, providing its activation "by ownself", being the only implant with this feature today 10, 11, 12, 13, 24 .

Discussion
Regarding the literature data about third generation Gamma Nail, Sim et al. 25 found the average operation time was 85 min, while Kelly et al. 18       Accepted September 23, 2020.