Description
The external surface (outer surface) of third rib is its smooth, convex, outer area. It is one of the two surfaces of the body of the third rib, the other being the internal surface.
The external surface of third rib consists of the angle, which is located on its posterolateral aspect. It provides:
—origin sites for the iliocostalis cervicis, pectoralis minor and serratus anterior muscles;
—insertion sites for the serratus posterior superior, levatores costarum breves, iliocostalis thoracis and longissimus thoracis muscles.