Computed tomography of sternoclavicular joint lesions in spondylarthropathies

To evaluate the computed tomography (CT) findings of inflammatory lesions of the sternoclavicular joints (SCJ) in spondylarthropathies.

CT scans of the SCJs were obtained in 23 patients (group 1) with inflammatory SCJ lesions in spondylarthropathies. These scans were reviewed by four readers and compared with the CT scans of 23 matched controls (group 2). Each reader had to complete a 27-item grid.

In the 23 patients of group 1, the mean number of observed signs was 5.3 +/- 4.2 higher (P < 0.01) than in the group of 23 matched controls (2.4 +/- 1.6). Four signs were more frequently observed (P < 0.05) in group 1: surrounded subchondral clavicular erosions and cysts, surrounded subchondral sternal cysts and sternal bone sclerosis. A cyst and/or an erosion was associated with hyperostosis and/or bone sclerosis in 9 of 23 patients in group 1. This association was not observed in group 2; the difference was significant (P < 0.001). A cyst and/or an erosive lesion was observed 18 times in group 1 versus 11 times in group 2; the difference was significant (P < 0.05). Conversely, signs of degenerative lesions (osteophytes, subchondral sclerosis, unevenness of joint surface) were no more frequently observed in controls than in group 1. This study emphasizes the diagnostic value of CT, in particular in the identification of inflammatory lesions, even when pre-existing degenerative disease is present.