Pyarthrosis of the manubriosternal joint is exceedingly rare. Its rarity defies an early diagnosis, and other causes of chest pain would normally be ruled out first. We describe a patient with a short history of chest pain, pyrexia, and raised inflammatory markers. A destroyed manubriosternal joint with a large abscess was found during surgical exploration. This case illustrates an unusually rapid development of septic arthritis involving a fibrocartilaginous joint in an otherwise healthy young man. Nine other cases have been described in the literature and are reviewed. Early diagnosis followed by adequate surgical drainage and antibiotic therapy led to a good outcome.