title: Bifid ribs observed in the third and the fourth ribs.
abstract: Three cases of bifid ribs were found in two cadavers during routine dissections at the Iwate Medical University School of Dentistry. All of the cases were found in the third or the fourth rib. The distal parts of the osseous rib bifurcated with an angle of 60 degrees and both of the branches had their own costal cartilage. The costal cartilage fused again to form the trunk which was connected to the sternum. The space between the two branches was filled with presumably normal intercostal muscles. Blood supply was maintained by a small branch from the interthoracic artery to the upper branches. However, the intercostal nerves did not branch toward the upper branch but only ran along the lower margins of the lower branches of the bifid ribs.
authors.affiliation: Department of Oral Anatomy 1, Iwate Medical University School of Dentistry, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Osawa
authors.forename: T
authors.initials: T
authors.lastname: Sasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: A
authors.initials: A
authors.lastname: Tsukamoto
authors.forename: M
authors.initials: M
authors.lastname: Onodera
authors.forename: E
authors.initials: E
authors.lastname: Nara
authors.forename: J K
authors.initials: JK
authors.lastname: Chen
authors.forename: A
authors.initials: A
authors.lastname: Fujimura
authors.forename: Y
authors.initials: Y
authors.lastname: Nozaka
mesh_terms: D000368:Aged; D002102:Cadaver; D002356:Cartilage / Q000002:abnormalities / Q000098:blood supply / Q000294:innervation; D006801:Humans; D007367:Intercostal Nerves / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D012272:Ribs / Q000002:abnormalities* / Q000098:blood supply / Q000294:innervation; D013895:Thoracic Arteries / Q000033:anatomy & histology