Evidence of Costoclavicular Joint as A Synovial Joint

Introduction: The present study was conducted to note the osteological evidence of a synovial joint between clavicle and first rib in Indians. Material and Methods: The present study was conducted on 310 pairs of adult clavicles and first ribs, out of which 210 pairs were males and 100 pairs were females obtained from the Anatomy department of Pt. B. D. Sharma Postgraduate Institute of Medical Sciences, Rohtak. The articular facets were studied and measured with the help of a sliding Vernier caliper (Micropole). Results: Among 210 pairs (420 no.) of male clavicles examined, 6 clavicles (2.86%) had a circumscribed smooth articular facet with well-defined margins. Out of these 6 clavicles, 3 (1.43%) were of right side and 3(1.43%) were of left side. A corresponding facet was present on the first ribs of the same skeletons. The facets were found to be present unilaterally and that too in males only. The measurements of the articular facets on the rhomboid area of the clavicles and ribs were-the average length, width and elevation was 7mm, 5.4mm and 2.2mm respectively. Conclusion: These articular facets on the rhomboid area of clavicles and first ribs are osteological evidence of a synovial articulation between clavicle and first rib.