Morphology of the First Rib of Koreans

Abstract

The 213 first ribs Koreans were measured and morphologically studied. The results were as follows. 1. On average, the internal straight length of the first rib was 53.7㎜ (male), 49.9㎜ (female) ; the external straight length was 79.7㎜ (male),

75.4㎜ (female), the maximum straight length was 87.4㎜ (male), 81.2㎜ (female) ; the breadth was 15.2㎜ (male), 14.4㎜ (female) ; and the thickness was 5.5㎜ (male), 5.4㎜ (female). 2. The proportion of the scalene tubercle to the costal breadth was 0% to 90% (average 37%). 3. The incidence of the presence of the groove for the first thoracic nerve was 7.5%. 4. The common shapes of the articular surface of the head were ball-shape(41%), cylinder-shape (25%) and plane-shape (25%) ; and those of the tubercle were cylinder-shape (44%), saddle-shape (31%) and socket-shape (14%).