出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/02/04 11:16:31」(JST)
Trapezoid bone | |
---|---|
Left hand anterior view (palmar view). Trapezoid bone shown in red.
|
|
The left trapezoid bone.
|
|
Details | |
Latin | os trapezoideum, os multangulum minus |
Articulations | articulates with four bones: scaphoid proximally |
Identifiers | |
Gray's | p.225 |
MeSH | A02.835.232.087.319.150.805 |
Dorlands /Elsevier |
o_07/12598807 |
TA | A02.4.08.010 |
FMA | 23724 |
Anatomical terms of bone |
The trapezoid bone (lesser multangular bone) is a carpal bone in tetrapods, including humans. It is the smallest bone in the distal row. It may be known by its wedge-shaped form, the broad end of the wedge constituting the dorsal, the narrow end the palmar surface; and by its having four articular facets touching each other, and separated by sharp edges. It is homologous with the "second distal carpal" of reptiles and amphibians.
The trapezoid is a four-sided carpal bone found within the hand. The trapezoid is found within the distal row of carpal bones.[1] :708
The superior surface, quadrilateral, smooth, and slightly concave, articulates with the scaphoid.
The inferior surface articulates with the proximal end of the second metacarpal bone; it is convex from side to side, concave from before backward and subdivided by an elevated ridge into two unequal facets.
The dorsal and palmar surfaces are rough for the attachment of ligaments, the former being the larger of the two.
The lateral surface, convex and smooth, articulates with the trapezium.
The medial surface is concave and smooth in front, for articulation with the capitate; rough behind, for the attachment of an interosseous ligament.
The carpal bones function as a unit to provide a bony superstructure for the hand.[1] :708
The etymology derives from the Greek trapezion which means "irregular quadrilateral," from tra- "four" and peza "foot" or "edge." Literally, "a little table" from trapeza meaning "table" and -oeides "shaped."
Position of trapezoid bone (shown in red). Left hand. Animation.
Trapezoid bone of the left hand. Close up. Animation.
Trapezoid bone.
Right hand posterior view (dorsal view). Thumb on bottom.
Trapezoid shown in yellow. Left hand. Dorsal surface.
Trapezoid shown in yellow. Left hand. Palmar surface.
Transverse section across the wrist (palm on top, thumb on left). Trapezoid bone shown in yellow (labelled as "Lesser Multang").
Cross section of wrist (thumb on left). Trapezoid shown in red (labelled as "Lesser Multang").
Wikimedia Commons has media related to Trapezoid bone. |
This article incorporates text from a public domain edition of Gray's Anatomy.
|
全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.
リンク元 | 「小菱形骨」 |
関連記事 | 「bone」 |
.