The incidence of neurovascular injury during external fixator placement without radiographic assistance for lower extremity diaphyseal fractures: a cadaveric study.
BACKGROUND
During military operations or mass casualty situations, trauma surgeons are called on to place external fixation without the use of fluoroscopy. However, the safety and efficacy of this procedure has not been investigated.


METHODS
Orthopedic surgeons, with varying experience, externally stabilized 20 fractured cadaver femora and tibiae. Using Behrens' safe zones, 194 half-pins were placed without radiographic assistance. Subsequently, fluoroscopy and dissections documented pin positions.


RESULTS
Of the 194 pins, there were three (1.5%) neurovascular injuries (popliteal artery trifurcation). Forty-nine percent (95 of 194) of pins were overpenetrated (greater than two threads out the second cortex), with the mean distance to neurovascular structures of 10.2 mm. The mean overpenetration was +5.2 threads (13 mm).


CONCLUSIONS
When compared with radiography-assisted fixation, our results show the risk for neurovascular injury doubles with pin placement without fluoroscopic assistance. At less than 2%, this may be an acceptable rate in battlefield/mass casualty situations. This study also demonstrates that increased experience with standard fixation correlates to safer pin placement feel-placed fixation. In austere conditions, experienced surgeons can safely place external fixators without radiographic guidance.
Topp
Raymond
R
Brooke Army Medical Center, 1315 Vista Del Monte, San Antonio, TX 78216, USA. rtopp@satx.rr.com
Hayda
Roman
R
Benedetti
Gary
G
Twitero
Trent
T
Carmack
David B
DB
D001858:Bone Nails; D002102:Cadaver; D018483:Diaphyses / Q000293:injuries* / Q000601:surgery; D005592:Fracture Fixation / Q000009:adverse effects*; D050723:Fractures, Bone / Q000601:surgery*; D006801:Humans; D015994:Incidence; D035002:Lower Extremity / Q000293:injuries*; D011150:Popliteal Artery / Q000293:injuries*; D017695:Soft Tissue Injuries / Q000209:etiology*