|Bone: Lower extremity of ulna
| Vertical section through the articulations at the wrist, showing the synovial cavities.
|| subject #52 218
The lower extremity of the ulna (or distal extremity) is small, and presents two eminences; the lateral and larger is a rounded, articular eminence, termed the head of the ulna; the medial, narrower and more projecting, is a non-articular eminence, the styloid process.
- The head presents an articular surface, part of which, of an oval or semilunar form, is directed downward, and articulates with the upper surface of the triangular articular disk which separates it from the wrist-joint; the remaining portion, directed lateralward, is narrow, convex, and received into the ulnar notch of the radius.
- The styloid process projects from the medial and back part of the bone; it descends a little lower than the head, and its rounded end affords attachment to the ulnar collateral ligament of the wrist-joint.
The head is separated from the styloid process by a depression for the attachment of the apex of the triangular articular disk, and behind, by a shallow groove for the tendon of the extensor carpi ulnaris.
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.
|Bones of upper limbs|
|Pectoral girdle, clavicle||conoid tubercle - trapezoid line - costal tuberosity - subclavian groove|
|Scapula||spine of scapula - suprascapular notch - acromion - glenoid cavity - glenoidal labrum - coracoid process - fossae (subscapular, supraspinatous, infraspinatous) - borders (superior, lateral/axillary, medial/vertebral) - angles (superior, inferior, lateral) - tubercles (infraglenoid, supraglenoid)|
|Humerus||upper extremity: necks (anatomical, surgical) - tubercles (greater, lesser) - intertubercular sulcus
body: radial sulcus - deltoid tuberosity
lower extremity: capitulum - trochlea - epicondyles (lateral, medial) - supracondylar ridges (lateral, medial) - fossae (radial, coronoid, olecranon)
|Forearm||ulna: upper extremity (olecranon, coronoid process, tuberosity, radial notch, semilunar notch) - body of ulna - lower extremity (styloid process)|
radius: upper extremity (tuberosity) - body - lower extremity (ulnar notch, styloid process)
|Hand||carpus: scaphoid - lunate - triquetral - pisiform - trapezium - trapezoid - capitate - hamate (hamulus) - metacarpus: 1st metacarpal - 2nd - 3rd - 4th - 5th - phalanges of the hand|