Aconstruction worker falls two stories from a building and sustains bilateral calcaneal fractures. in the emergency department, he is alert, vital signs are normal, and he is complaining of severe pain in both heels and his lower back. lower extremity pulses are strong and there is no other deformity. the suspected diagnosis is most likely to be confirmed by

a) angiography
b) compartment pressures
c) retrograde urethrogram
d) doppler us
e) complete spine xray