Lunate bone


Lunate bone
Bone: Lunate bone "Cow chin Bone"
Carpus.png
Shown is the right hand, palm down (left) and palm up (right).
Proximal: A=Scaphoid, B=Lunate, C=Triquetral, D=Pisiform
Distal: E=Trapezium, F=Trapezoid, G=Capitate, H=Hamate
Gray222.png
The left lunate bone
Latin os lunatum
Gray's subject #54 224
Articulations radius proximally
capitate and hamate distally
scaphoid laterally
triangular medially  
MeSH Lunate+Bone

The lunate bone (semilunar bone) is a carpal bone (wrist bone) in the human hand that may be distinguished by its deep concavity and crescentic outline. It is situated in the center of the proximal row of the carpus (wrist) region between the fore arm and hand (manus). In standard medical posture, the lunate carpal bone is situated between the lateral Scaphoid bone and medial Triquetral bone. The lunate carpal bone straddles distally the bordering ulna and radius bones and proximally to distal carpus (wrist) Trapezium bone and Trapezoid bone.

The etymology of the Lunate bone derives from the Latin luna which means "moon", the lunate bone looks semi-similar to a crescent moon. In amphibians and reptiles, the bone is instead referred to as the intermedium, because of its position between the other two proximal carpals.

Contents

Surfaces

The superior surface, convex and smooth, articulates with the radius.

The inferior surface is deeply concave, and of greater extent from before backward than transversely: it articulates with the head of the capitate, and, by a long, narrow facet (separated by a ridge from the general surface), with the hamate.

The dorsal and palmar surfaces are rough, for the attachment of ligaments, the former being the broader, and of a somewhat rounded form.

The lateral surface presents a narrow, flattened, semilunar facet for articulation with the scaphoid.

The medial surface is marked by a smooth, quadrilateral facet, for articulation with the triangular bone.

Clinical relevance

Perilunar dislocation as seen on x-ray.

The lunate bone is the most frequently dislocated carpal bone.

See also

Additional images

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.


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Look at other dictionaries:

  • lunate bone — n a crescent shaped bone that is the middle bone in the proximal row of the carpus between the scaphoid bone and the triquetral bone and that has a deep concavity on the distal surface articulating with the capitate called also lunate, semilunar… …   Medical dictionary

  • lunate bone — noun one of the eight small wrist bones • Syn: ↑semilunar bone, ↑os lunatum • Hypernyms: ↑carpal bone, ↑carpal, ↑wrist bone * * * noun Etymology: probably translation of ( …   Useful english dictionary

  • lunate bone — noun One of the carpal bones of the wrist. Syn: os lunatum, semilunar bone …   Wiktionary

  • lunate bone — a bone of the wrist (see carpus). It articulates with the capitate and hamate bones in front, with the radius behind, and with the triquetral and scaphoid at the sides …   The new mediacal dictionary

  • Кость Полулунная (Lunate Bone) — кость запястья (см. Запястье). Спереди соединяется с головчатой и крючковидной костями, сзади с лучевой костью, а с боков с трехгранной и ладьевидной костями. Источник: Медицинский словарь …   Медицинские термины

  • Bone — This article is about the skeletal organ. For other uses, see Bone (disambiguation) and Bones (disambiguation). For the tissue, see Osseous tissue. Drawing of a human femur Bones are rigid organs that constitute part of the endoskeleton of… …   Wikipedia

  • lunate — 1. SYN: lunar (2). 2. Relating to the l. bone. * * * lu·nate lü .nāt adj shaped like a crescent lunate n LUNATE BONE * * * lu·nate (looґnāt) [L. luna moon] moon shaped, or crescentic; see os lunatum …   Medical dictionary

  • lunate — [ lu:neɪt] adjective crescent shaped. noun 1》 Archaeology a crescent shaped stone implement. 2》 (also lunate bone) Anatomy a crescent shaped carpal bone in the centre of the wrist. Origin C18: from L. lunatus, from luna moon …   English new terms dictionary

  • lunate — adj. & n. adj. crescent shaped. n. a crescent shaped prehistoric implement etc. Phrases and idioms: lunate bone a crescent shaped bone in the wrist. Etymology: L lunatus f. luna moon …   Useful english dictionary

  • Bone — is the substance that forms the skeleton of the body. It is composed chiefly of calcium phosphate and calcium carbonate. It also serves as a storage area for calcium, playing a large role in calcium balance in the blood. The 206 bones in the body …   Medical dictionary