Abstract
Introduction:-In the thorax there are normally 11 pairs of intercostal spaces, that contain intercostal muscles, intercostal nerves and vessels. Bifurcation of the ribs and presence of additional intercostal spaces is a rare variation of the thoracic wall .This may be due to defect in the process of segmentation of the developing somites.
Case Report:- During a routine dissection for undergraduate medical students ,we observed a variation involving the right 4th and 5th ribs and its costal cartilages in the human cadaver of a man of Indian ethnicity aged about 55 years. The right 4th and 5th ribs and their costal cartilages were bifurcated at their costochondral junction enclosing two small circular additional intercostal spaces. Muscles covered with deep fascia were present in these circular intercostal spaces. Muscles received nerve supply from the collateral branches of 3rd and 4th intercostal nerves respectively.
Conclusion:-These anomalies may remain asymptomatic, can create misinterpretations during radiological or physical examinations. The knowledge about these variations will be helpful to reduce incidences of misinterpretations.
Keywords:- rib bifurcation, intercostal space, Gorlin’s syndrome.
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Corresponding Author
Dr. Deepshikha Singh
Junior Resident, Department of Anatomy
IMS, BHU, Varanasi-221005, Mob.9532188506
Email-This email address is being protected from spambots. You need JavaScript enabled to view it.
DOI: http://dx.doi.org/10.18535/jmscr/v3i11.06
