Articular facets of the coracoclavicular joint in Koreans

This study was performed to investigate the occurrence of the coracoclavicular joint in Koreans. Materials used in this study were paired clavicles and scapulae obtained from 102 adult Korean cadavers (61 males, 41 females) ranging from 18 to 97 years in age. The occurrence of the joint was identified by a definite articular facet on the conoid tubercle of the clavicle and also by one on the superomedial surface of the coracoid process of the scapula. To compare the morphometric differences between specimens with and without coracoclavicular joint, the clavicle length, scapular border length, glenoid length, coracoid height, coracoacromial (CA) arch height, coracoid slope, and acromion slope were measured on all bones examined. The coracoclavicular joint was found in 10 (9.8%) of 102 individuals examined. Among them, nine (8.8%) showed bilateral coracoclavicular joints, and a unilateral right joint was noted in one case (1.0%). No significant difference in the incidence of the joint was noted between the right and left side. The incidence of the joint in males, a frequency of 9.8%, was the same as that in females. The joint was not found in individuals under 40 years old. However, the joint was present in 9.5% of those aged 40-59 years, and in 11.4% of those aged 60 years or over. There was no significant difference between various measurements taken from specimens with and without a coracoclavicular joint. These findings suggest that the occurrence of the coracoclavicular joint is related to aging, but not to the size of the scapulae or the slopes and heights of some CA arch elements.