An underdiagnosed fracture typically involving the 5th to 9th costal ribs, which is caused by opposing muscular forces in the middle of the rib at the axillary line from the serratus anterior and the external oblique muscles. Such fractures occur during episodes of violent coughing, and are more common in elderly females with osteoporosis.
Clinical findings Acute chest pain after a paroxysm of coughing or sneezing
Complications Rare, but include pneumothorax, bleeding and intercostal pulmonary hernia.
References Am J Emerg Med. 1984 Nov;2(6):513-7
World J Emerg Surg. 2006; 1: 34.