Bicipital Ribs- A Report of Four Cases.

The Thoracic outlet is bounded by the first thoracic vertebra posteriorly superior border of manubrium sternum anteriorly, and the first rib and costal cartilage laterally. Thoracic outlet syndrome is a common term for a number of disorders producing neurovascular compression over this area. In the collection of bones in the Institute of Anatomy, Madras Medical College. Bicipital ribs i.e., fused first and second ribs were found which is one of the important bony factor leading to thoracic outlet syndrome. The present report will be useful to clinicians while dealing with thoracic outlet syndrome.

An unusual case of Synostosis of first and second rib.

Introduction: Congenital anomalies of the ribs are not so common but they are usually discovered as an incidental finding on routine radiography. Bicipital rib results due to fusion of cervical rib with the first rib or the first rib with the second. Its occurrence is not uncommon and more frequently unilateral. Observation: During routine course of osteology teaching we observed that the first rib had fused with the superior surface of second rib, on the left side. Fusion between the ribs had occurred 3cms from the tubercle of the first rib obliterating the first intercostal space anteriorly. Conclusion: The incidence of synostosis of ribs is 0.3% of the population. It is usually asymptomatic but they may cause musculoskeletal pain or intercostal nerve entrapment. Involvement of the 1st rib is one of the causes of thoracic outlet syndrome. A rib anomaly usually indicates an underlying systemic disease and might need surgical intervention. Hence the present paper is an attempt to highlight its morphological implications and clinical significance