Ossification patterns Flashcards
Metacarpals
one center for each metacarpal body
digits 2-5: one center for each metacarpal head
digit 1: one center for each metacarpal base
Clavicle
Primary: medial and lateral, intermembranous ossification
Secondary: sternal end
Lumbar vertebrae
Primary: 2 neural arches, 1 centrum
Secondary: 2 mammillary processes, 1 spinous process, 2 anular epiphyses
Coccyx
Primary: 1 centrum
Secondary: 2 neural arches at Co1, 2 transverse processes at Co1
Radius
Primary: body (8th week)
Secondary: head (9-13, earlier for females), distal end (20th year)
Atlas
Primary: 2 neural arches
Secondary: 2 transverse processes, 1 posterior arch
Ribs 1-10
Primary: 1 for body
Secondary: 3 (head, articular part of tubercle, non-articular part of tubercle)
Thoracic vertebrae
Primary: 2 neural arches, 1 centrum
Secondary: 2 transverse processes, 1 spinous process, 2 anular epiphyses
Ribs 11 and 12
Primary: body
Secondary: head
Humerus
Primary: body
Secondary: head (blend by 5th year, unite age 20), greater tubercle(blend by 5th year, unite age 20), lesser tubercle(blend by 5th year, unite age 20), capitulum (16th year), trochlea (16th year), medial (18th year) and lateral (16th year) epicondyles
Sacrum
Primary: 1 centrum, 2 vertebral arches
Secondary: 10 anular epiphyses, 3-4 spinous processes, 6-10 transverse processes, 2 mammillary processes at superior articular processes
Phalanx
one center for each body
one center for each phalanx base
Carpals of hand
one center
Scapula
Primary: body of scapula (8th week)
Secondary: 2 for coracoid process (17th year), 2 for acromion process (15, 16th year), inferior angle (16th year), medial/vertebral border (17th year), glenoid cavity (
Sternum
1 in manubrium (5-6 fetal month)
4-5 in body of sternum (could be 1 ossification center or 2 on different sides) (7th fetal month to 20th year; fusion happens through puberty into early adulthood)
