Hemothorax and Pneumothorax Secondary to Costal Involvement in Hereditary Multiple Exostoses: A Systematic Review of Reported Cases in the Literature.

Hereditary multiple exostoses (HME) are an autosomal dominant skeletal disorder characterized by the development of multiple benign osteochondromas (exostoses) that frequently involve long bones of the body. Less commonly, the ribs are a site of involvement, and long-term friction between an exostosis and pleura can produce a hemothorax or pneumothorax. The purpose of this study is to provide a comprehensive review of existing literature on pneumothorax or hemothorax secondary to costal exostosis in HME patients. We reviewed the databases of PubMed and Embase and included data as current as of February 15, 2021. All case reports included cases of hemothorax or pneumothorax in patients with a known personal or family history of HME. After evaluation for inclusion based on eligibility criteria, 18 cases were included. The average age at presentation was 11.7 years (range: 3-32), and most patients were male (83%). Hemothoraces occurred in 15 cases, while pneumothoraces occurred in three cases. All cases were evaluated using chest X-ray and CT scan, and the majority of the cases were treated with surgical resection of the exostosis, either with video-assisted thoracoscopic surgery (VATS; 61%) or thoracotomy (22%). Outcomes were successful with no cases of recurrence after surgical intervention. Although rare, costal exostosis should be considered as a differential in patients presenting with pneumothorax or hemothorax and past medical history or physical exam findings suggestive of HME. Immediate evaluation and surgical intervention to resect costal exostosis are essential to reduce the risk of recurrent life-threatening injury.