From 1990 through 1993 nine patients presented with unexplained swelli
ng of the sternoclavicular joint. In some cases a tumor was suspected.
The clinical histories included trauma with injury of forearm and wri
st or strain on the shoulder girdle without acute onset of any symptom
s in the sternoclavicular joint. In trauma cases the time from injury
to onset of symptoms was between 1 day and 1 year (median 5 weeks). CT
studies demonstrated widening of the joint space in two cases, thicke
ning of the pectoral muscle in six cases and thickening of capsule and
ligaments in five cases. In one case arthroplasty of the sternoclavic
ular joint was performed and in a second we performed a biopsy. The re
maining cases were not treated. Other differential diagnoses to be con
sidered in the case of a swelling of the sternoclavicular joint are li
sted.