Osteology of the upper limb - radius, ulna and carpus (dave's notes) Flashcards
When is the cartilage of the radius formed? When does this begin ossification?
Cartilage at the 6th week, primary centre appears in the middle in the 8th week. Both ends are cartilaginous at birth.
Describe the development of the lower (growing) end of the radius.
The centre appears at the end of year one and fuses at 20. The epiphyseal line is at the junction of the head and neck.
Describe the development of the upper end of the radius.
Centre appears at 4 years and fuses at 12. The epiphyseal line is at the junction of the head and neck.
When is the cartilage of the ulna formed? When does this begin ossification?
Cartilage 6th week
Primary centre appears in the middle in the 8th week.
Which is the growing end of the ulna? When does this ossify and fuse?
The head. This is not ossified until the 6th year and does not fuse until 20.
Describe the development of the upper end of the ulna
The upper end shows only a small epiphysis 10th-18th. Grown in size and shape to adjust to trochlear.
Describe the carpus at birth
All cartilagenous. Each carpal bone ossifies from one centre.
Which carpal bone ossifies first, and which last? What about the other carpal bones?
Capitate - largest - ossifies at 1 year.
Psiform - smallest - ossifies at 10 years.
The others ossify according to size, and are generally complete at year 7 (excl pisiform)
When do the shaft of the metacarpals and phalanges ossify?
In utero, but at birth there is a cartilaginous epiphysis at every bone.
??Where do the phalanges and metacarpals grow from?? ??ossify??
Phalanges ??base
Metacarplas ??head
The thumb metacarpal ossifies like a phalanx.
When do the cartilaginous epiphyses ossify and then fuse?
Ossify between years 2-3 and fuse at 20.
