Sternoclavicular septic arthritis: review of 180 cases.

We review 170 previously reported cases of sternoclavicular septic arthritis, and report 10 new cases. The mean age of patients was 45 years; 73% were male. Patients presented with chest pain (78%) and shoulder pain (24%) after a median duration of symptoms of 14 days. Only 65% were febrile. Bacteremia was present in 62%. Common risk factors included intravenous drug use (21%), distant site of infection (15%), diabetes mellitus (13%), trauma (12%), and infected central venous line (9%). No risk factor was found in 23%. Serious complications such as osteomyelitis (55%), chest wall abscess or phlegmon (25%), and mediastinitis (13%) were common. Staphylococcus aureus was responsible for 49% of cases, and is now the major cause of sternoclavicular septic arthritis in intravenous drug users. Pseudomonas aeruginosa infection in injection drug users declined dramatically with the end of an epidemic of pentazocine abuse in the 1980s. Sternoclavicular septic arthritis accounts for 1% of septic arthritis in the general population, but 17% in intravenous drug users, for unclear reasons. Bacteria may enter the sternoclavicular joint from the adjacent valves of the subclavian vein after injection of contaminated drugs into the upper extremity, or the joint may become infected after attempted drug injection between the heads of the sternocleidomastoid muscle. Computed tomography or magnetic resonance imaging should be obtained routinely to assess for the presence of chest wall phlegmon, retrosternal abscess, or mediastinitis. If present, en-bloc resection of the sternoclavicular joint is indicated, possibly with ipsilateral pectoralis major muscle flap. Empiric antibiotic therapy may need to cover methicillin-resistant Staphylococcus aureus (MRSA).