Clavicle锁骨 Sterna end胸骨端 medial ly and acron i al end肩峰 端 latera “S” shaped, medial2/3 convex forward and lateral 1/3 convex backwardClavicle 锁骨 ◼ Sternal end胸骨端 medially and acromial end肩峰 端 laterally ◼ “S” shaped, medial 2/3 convex forward and lateral 1/3 convex backward