16-Detector multislice CT in the detection of stress fractures: a comparison with skeletal scintigraphy.
OBJECTIVE
To test the hypothesis that the improved resolution afforded by 16-detector computed tomography (CT) would translate to better stress fracture detection when compared with skeletal scintigraphy.


METHODS
Thirty-three cases of suspected stress fractures in 26 patients were investigated using skeletal scintigraphy and 16-detector CT performed on the same day. Planar images of the lower limbs were taken 3h post-injection of 400MBq (99m)Tc-methylene diphosphonate ((99m)Tc-MDP). (99m)Tc-MDP uptake was quantified at suspected fracture sites. CT was performed using a 16-detector multisection machine employing 0.75mm detectors and images reconstructed in 0.5mm increments. Examinations were reported independently and discordant results were compared at follow-up.


RESULTS
At initial reporting scintigraphy identified fractures in 13 of the 33 cases and CT identified four of the 33. In one case, on review of the CT images, a fracture was present in the distal fibula that was not initially identified. This resulted in eight scintigraphic-positive CT-negative discordant cases. The (99m)Tc-MDP uptake was significantly lower in the discordant fracture group compared with the concordant group (p<0.01).


CONCLUSIONS
Despite technological advances in CT, scintigraphy appeared to detect more stress fractures. As such, multidetector CT should not be used as a routine initial investigation in stress fracture detection. The potential use of (99m)Tc-MDP quantification at fracture sites is of interest and may be worth further investigation.
Groves
A M
AM
Department of Radiology, Addenbrooke's Hospital NHS Trust, University of Cambridge, Cambridge, UK. drashleygroves@hotmail.com
Cheow
H K
HK
Balan
K K
KK
Housden
B A
BA
Bearcroft
P W P
PW
Dixon
A K
AK
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005360:Fibula / Q000000981:diagnostic imaging; D015775:Fractures, Stress / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate; D013978:Tibial Fractures / Q000000981:diagnostic imaging; D036542:Tomography, Spiral Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate