32 骺板（epiphyses）之次級骨化中心主要出現於何時？

 胚胎發育後期 出生時 出生後的數年 青春期至20歲前

ans: C

CRITOE: Elbow Ossification Order Written by Admin Sunday, 20 July 2008 12:22 At birth the distal humeral, proximal radial and ulnar epiphyses are cartilaginous. Six ossification centers (four in the distal humerus, one each in the proximal radius and ulna) develop in an orderly sequence. The mnemonic "CRITOE" is helpful to remember the typical order: Capitellum (6 months - 2 years) Radial head (3 - 6 years) Internal (medial) epicondyle (4 - 7 years) Trochlea (7 - 10 years) Olecranon (6 - 12 years) External (lateral) epicondyle (10 - 14 years) The ossification centers appear earlier in girls. The ossification centers are usually ovoid and smooth with the exception of the trochlea, which can be fragmented and irregular. The knowledge of this ossification sequence is especially helpful in medial epicondyle injury.