Background: A synovial coracoclavicular joint (CCJ) is a rare finding in human. When present, this anomalous joint is variably reported as a cause of shoulder pain. Up to date, there are no reports on the incidence of the coracoclavicular joint among Egyptians.
Aim: The aim of the present study was to report on the incidence of this joint among adult Egyptian population, and to report on the differences, if any, of the morphometry of the clavicles and scapulae and to clarify whether the occurrence of this CCJ was associated with a shoulder pain or not.
Materials and Methods: This study was conducted on a sample of 100 adult human clavicles and scapulae, chest radiographs of 200 different patients and chest computed tomography (CT) of 80 patients. Variable morphometric measurements were taken from all assessed bones, chest radiographs and CT. Regarding of the positive cases in the chest radiographs and CT, the clinical history was obtained to assess the incidence of symptomatic cases. Statistical analysis was also performed using a level of significance of p < 0.05.
Results: CCJ was found in 28 out of the 380 studied samples with an incidence of (7.5 %). No significant sex distribution was found while there was a significant association as regards aging and presence or absence of shoulder pain.
Conclusion: The Egyptian population showed a CCJ incidence of 7.5%, which was comparable to other ethnic groups in world population. The CCJ should be put in mind as a differential diagnosis for unexplained shoulder pain, especially in older patients.