Sternocostal triangle
Trigonum sternocostale
- Synonym: Sternocostal hiatus
- Eponym: Larrey's triangle; Foramina of Morgagni;
Definition
The sternocostal triangle is a paired, right and left, area of weakness in the diaphragm, located between its sternal portion and its costal portion.
It is bounded by:
– medially: the lateral border of the sternal part of the diaphragm
– laterally: the medial border of the costal part of the diaphragm
– anteriorly (ventral): the musculoaponeurotic plane formed by the transversus thoracis muscle (above) and the transversus abdominis muscle (below)
Dissection studies (Baudoin et al., 2003; Medical University of Vienna, 2025) consistently show that the vessel runs anterior (ventral) to this musculoaponeurotic plane; that is, anterior to the diaphragm, between the costal margin and the abdominal wall, without crossing either the pleural or peritoneal cavity. No vascular structures are identified within the triangle itself.
Clinical relevance: the sternocostal triangle is the site of predilection for Morgagni's hernia.
References
This definition incorporates text from the wikipedia website - Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved August 10, 2004, from http://www.wikipedia.org
Imaging-Anatomic Study of Diaphragmatic Sternocostal Triangle With Double-Phase 16-Row MDCT.Deng Y, Yang Z, Ma E.Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. 2010;27(2):260-5
