Relationship between distal screws and femoral arteries in closed hip nailing on computed tomography angiography

Iatrogenic vascular injury as a result of closed hip nailing is not common, but is a regularly reported complication after hip fracture surgeries. To prevent vascular injury in closed hip nailing by identifying the range of distances and angles between deep and superficial femoral arteries (DFAs and SFAs) and distal screws. Forty subjects who underwent computed tomography angiographies were included in this study. Imaginary lines marking the distal screws (proximal femoral nail antirotation-II [PFNA-II], 180 and 300 mm; inter-trochanteric/sub-trochanteric nails [ITST], 200 and 300 mm) were drawn on the scout film. On arterial phase images, angles between distal screw lines and those marking DFAs or SFAs, as well as the distance between each artery and far cortex, were measured using the cross-reference capabilities of the picture archiving and communication system. The short nails (PFNA-II 200 mm and ITST 180 mm) were closest to the DFAs, indicating that these nails are most likely to cause injury (PFNA-II 200 mm: 11.2 ± 13.7° anterior and 9.87 ± 5.83 mm; ITST 180 mm: 22.56 ± 15.92° posterior and 9.24 ± 4.74 mm). The short nails were relatively distant from the SFAs, which were located posteriorly to the long nails (PFNA-II 300 mm and ITST 300 mm). These data indicate that insertion of distal screws into intramedullary nails increases the risk of injury to vascular structures. Surgeons must take care in drilling or inserting screws to ensure the prevention of vascular injury.