Brief communication: coracoclavicular joint in Northwest Indians.

The incidence of an articular facet on the conoid tubercle of the clavicle indicating the presence of a coracoclavicular joint was studied in paired clavicles obtained from 1,000 adult subjects aged 18 to 95 years (748 males, 252 females), and 75 children (45 males, 30 females) of known age on whom a medicolegal postmortem had been performed by the second author during 1972-90. The subjects were inhabitants of northwest India. In addition, paired clavicles from 50 neonates and 35 fetuses were also examined. The facet was absent in the fetuses, neonates, and young children. The youngest clavicle showing the facet was from a girl of 13 years, in which it was present bilaterally. In adults the incidence of the facet was 10.1% (bilateral 5.7%, unilateral 4.4%) in males and 8.3% (bilateral 3.6%, unilateral 4.8%) in females. Absence of the facet in the fetuses, neonates, and young children shows that it is not a congenital anomaly.