bifid rib

{{Infobox medical condition (new)

| name = Bifurcated rib

| image = Gabelrippe C4 rechts im Roentgen - Annotation.jpg

| caption = Bifid rib at the right side seen on chest radiograph. The fourth rib splits in two towards the sternal end.

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| field = Medical genetics

| synonyms = Bifurcated rib, sternum bifidum

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A bifid rib is a congenital abnormality of the rib cage and associated muscles and nerves which occurs in about 1.2% of humans. Bifid ribs occur in up to 8.4% of Samoans.{{cite book |last= McKinley |first= Michael |author2=O'Loughlin, Valerie Dean |year= 2008 |title= Human Anatomy |url= https://archive.org/details/humananatomynded00mcki |url-access= limited |edition= 2nd |publisher= McGraw-Hill |isbn= 978-0-07-128320-5 |page= [https://archive.org/details/humananatomynded00mcki/page/n244 214]}} The sternal end of the rib is cleaved into two. It is usually unilateral.{{cite journal |last1=Oner |first1=Zulal |last2=Oner |first2=Serkan |last3=Sahin |first3=Necati Emre |last4=Cay |first4=Mahmut |title=Evaluation of congenital rib anomalies with multi-detector computed tomography in the Turkish population |journal=Folia Morphologica |date=26 January 2023 |doi=10.5603/FM.a2023.0006|pmid=36794687 |s2cid=256899032 |doi-access=free }}

Bifid ribs are usually asymptomatic, and are often discovered incidentally by chest X-ray. Effects of this neuroskeletal anomaly can include respiratory difficulties, neurological difficulties, limitations, and limited energy from the stress of needing to compensate for the neurophysiological difficulties. An unstable bifid rib may lead to slipping rib syndrome.{{Cite journal |vauthors=Mazzella A,Fournel L,Bobbio A, et al |title=Costal cartilage resection for the treatment of slipping rib syndrome (Cyriax syndrome) in adults|journal=Journal of Thoracic Disease|year=2020 |volume=12|issue=1|pages=10–16|doi=10.21037/jtd.2019.07.83|pmc=6995823|pmid=32055418 |doi-access=free }}

Another association is with odontogenic keratocysts of the jaw, which may behave aggressively and have a high propensity to recur when treated with simple enucleation and curettage. When seen together, the patient is likely to have nevoid basal-cell carcinoma syndrome (Gorlin-Goltz syndrome).