Elbow joint is characterized by 6 secondary ossification centers; in the capitulum, trochlea, lateral and medial epichondyles, olecranon and head of the radius. They are present on plane elbow radiograph at different time easily remembered by the mnemonic CRITOE: Capitulum 2years; Radial head 4 years; Internal (medial) Epicondyle 6 years; Trochlea 8 years; Olecranon 10 years; external (lateral) Epicondyle 12 years 
A prospective cross sectional hospital based study is conducted in period from December 2009 to December 2010 in which data was collected from 5 hospitals which provide services for the majority of the Khartoum state residents. The study aim to To assess the time of closure of secondary ossification centers in Sudanese children.
Patient & methods: A prospective cross sectional hospital based study is conducted in period from December 2009 to December 2010 in which data was collected from 5 hospitals; Khartoum, Khartoum North, Omdurman, Police, and Um badda. These hospitals provide services for the majority of the Khartoum state residents. Fifty seven AP and Lateral plane elbow X- ray were taken for healthy Sudanese children (40 Males and 17 Females) aged 13 - 23 years, whom sought medical counseling for skeletal problems at those hospitals.
Results In this study, the films of the 1st group (at average of 14 year) no one has closed RH, while only 20% of them show closed OC, ME, and LE, and 40% show closed T & C. In the 2nd group (at average of 17 year), 60% have closed RH physis, 63.3% Tr, while 66.7% show closed OC, 73.3% ME, and 90% for LE, and Cap. All children above 19Ys (3rd group) have closed physis (see table 4.1). The female physeal fusion precedes the male one in all the 6 centers
Conclusion: The study showed that all the 6 centers fuse to the shaft between 15 & 19 Ys, that all were ossified above 19Ys, but are still open at & below 14 Ys.Female’s fusion precedes males in all 6 centers. Order of fusion starts at trochlea, then capitulum followed by lateral epicondyle, medial epicondyle, olecranon, and finally radial head.