OBJECTIVETo explore the manifestation of CT for excavated-type of rhomboid fossa of the clavicle.

METHODSNine cases with rhomboid fossaes of the clavicle of 8 patients accepted CT and 1 case added MRI together;all 8 patients were male who aged from 17 to 70 years old with mean age of 42.5 years old;three dimensional reconstruction of all CTs were made, the distance between focus and inside end of clavicle and the size of all focus were measured respectively, then the position, shape, margin of focus were analyzed.

RESULTSAll focuses located near the inside end of clavicle and the distances between focus and inside end of clavicle were lower than 2 cm and the mean value was 1.3 cm, the size of all focuses was from 1.05 to 3.45 cm and the mean value was 2.18 cm. All 9 focuses of 8 patients located in the posterior and nether edge of inside end of clavicle, 5 cases located in right and 4 cases located in left side(both right and left side occurred in 1 patient. Seven focuses showed "fishhook sign" and the rest 2 focuses were small and without fishhook shape;the cortex of clavicle of all 9 cases showed local minus and nearly marrow showed integrated sclerotic margin. Regular soft tissue as strip can be seen in 7 focuses and the rest small focuses without the symptom.

CONCLUSIONSCT could show certain characteristics for excavated-type of rhomboid fossa of the clavicle and certain value for its diagnosis and identification.