The authors examined lower-limb CT angiograms of 47 patients (mean age 69) who had the scans performed for reasons other than a femoral fracture. They then measured the distance from the tip of the greater trochanter to the profunda femoris artery and its perforators within 5 mm of the medial femoral shaft, along the length of typical placement of dynamic hip screws used for fixation of proximal femoral fractures. (The authors assumed the use of a 4-hole, 78 mm plate or a 6-hole, 110 mm plate.)
All 47 patients had 2 vessels within 5 mm of the medial femoral shaft along the line of presumed dynamic hip screw insertion. Noting that these vessels could be damaged by reduction instruments or during drilling and plate-screw insertion during actual cases of femoral-fracture fixation, Jaipurwala et al. make the following suggestions:
- Avoid or take special care when drilling or inserting screws along the femoral shaft from 110 to 120 mm from the tip of the greater trochanter in women and from 120 to 130 mm in men.
- If possible, avoid inserting a screw in the fourth hole of a 4-hole dynamic hip screw plate or inserting a screw in the fourth and fifth holes of a 6-hole plate.
The authors emphasize that these suggestions are based on measurements taken from patients who did not have a hip fracture and that “a femoral fracture may potentially alter local anatomy because of swelling and damage to surrounding structures.” But they conclude that the risk of vascular injuries in patients with a proximal femoral fracture would be further reduced if surgeons took these findings into account during operative planning and execution of hip-fracture fixation.