Abstract
PURPOSE: To evaluate normal variations and thus to avoid confusion in differentiation from lesions of the
accessory structures (rhomboid fossa, foramen for supraclavicular nerve, conold tubercle) of the clavicle in chest
radiographs.
MATERIALS AND METHODS: We studied the variations of the clavicle in 300 chest radiographs (134 men, 166
women) and 355 dry bones (right 166, left 189; 151 men, 74 women, 130 unknown sex).
RESULTS: In chest radiographs, the incidence of the depressed rhomboid fossa was 229 cases (39.5%;male
52.0%, female 29.9%);the flat type was 329 cases (56.9%;male 45.7%, female 65.7%);and the elevated type
was 20 cases (3.5%; male 2.4%, female 4.3%). In the dry bones, the incidence of the depressed thombold fossa
was 129 cases (57.3%;male 59.6%, female 52.7%);the flat type was 65 cases (28.9%;male 24.5%, female 37.
8%) ;and the elevated type was 31 cases (13.8%;male 15.9%, female 9.5%). The incidence of the foramen for
supraclavicular nerve was 0.8% in chest radiographs, and 1.4% in the dry bones. The incidence of the elevated
conold tubercle was 65.1% (male 64.0%, female 65.9%) in chest radiographs, and 96.9% (male 95.4%, female
100.0%) in the dry bones.
CONCLUSIONS: The incidence of the depressed rhomboid fossa in chest radiographs was higher in men and
the right clavicle. The incidence of flat rhombo~d fossa in chest radiographs decreased according to increase of
age. The foramen for supraclavicular nerve was occasionally found (0.8% in chest radiographs; 1.4% in the dry
bones).