Spina vestibuli

Below the opening of the orifice of the coronary sinus they fuse to form a triangular thickening—the spina vestibuli. Below the opening of the orifice of the coronary sinus they fuse to form a triangular thickening—the spina vestibuli. This article incorporates text in the public domain from page 510 of the 20th edition of Gray's Anatomy (1918)