- Trapezium (bone)
Infobox Bone
Name = Trapezium (bone)
Latin = os trapezium, os multangulum majus
GraySubject = 54
GrayPage = 225
Caption = BONES OF HAND
"Proximal:" A=Scaphoid, B=Lunate, C=Triquetral, D=Pisiform
"Distal:" E=Trapezium, F=Trapezoid, G=Capitate, H=Hamate
Caption2 = Trapezium
Origins =
Insertions =
Articulations = 1st metacarpal distallyscaphoid proximallytrapezoid medially
2nd metacarpal medially
MeshName = Trapezium+Bone
MeshNumber = A02.835.232.087.319.150.800
DorlandsPre = o_07
DorlandsSuf = 12598800
The trapezium bone (greater multangular bone) is a carpal bone, in what is commonly referred to as thewrist .The trapezium is distinguished by a deep groove on its palmar surface. It is situated at the radial side of the
carpus , between thescaphoid and the firstmetacarpal bone.The etymology derives from the Greek "trapezion" which means "irregular quadrilateral;" literally, "a little table," from "trapeza" meaning table. Also, from "tra-" "four" and "peza" "foot" or "edge."
urfaces
The "superior surface" is directed upward and medialward; medially it is smooth, and articulates with the
scaphoid ; laterally it is rough and continuous with the lateral surface.The "inferior surface" is oval, concave from side to side, convex from before backward, so as to form a saddle-shaped surface for articulation with the base of the
first metacarpal bone .The "dorsal surface" is rough.
The "palmar surface" is narrow and rough. At its upper part is a deep groove, running from above obliquely downward and medialward; it transmits the tendon of the
Flexor carpi radialis , and is bounded laterally by an oblique ridge. This surface gives origin to theOpponens pollicis and to theAbductor andFlexor pollicis brevis ; it also affords attachment to thetransverse carpal ligament .The "lateral surface" is broad and rough, for the attachment of ligaments.
The "medial surface" presents two facets; the upper, large and concave, articulates with the
trapezoid ; the lower, small and oval, with the base of thesecond metacarpal .Tubercle of trapezium
The tubercle of trapezium is a
anatomic tubercle , where sometimesabductor pollicis brevis muscle attaches.See also
*Bone terminology
*Terms for anatomical location
*Finger
*Hand
=Additional
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