Clinical findings:
(1) insidious onset of pain
(2) pain localized to the sternoclavicular joint
(3) pain referred to shoulder or neck
(4) limited shoulder motion AND lack of pain in glenohumeral joint
(5) fever is variable
(6) any effusion tends to be limited because of the nature of the joint capsule
(7) spread of infection into adjacent structures (mediastinum, pleural space, chest wall, other)
Laboratory findings:
(1) Leukocytosis is variable.
(2) A needle aspiration may be unsuccessful if the amount of fluid is small, so an incision and drainage may be necessary to obtain diagnostic material.
Imaging studies:
(1) possible evidence of osteomyelitis
(2) CT or MRI scans are useful to document spread into adjacent structures
