[X]
01
Click on the structure to specify the target of your label
01
  • labels

Scaphoid

Other Terms: Navicular bone of hand, Scaphoid bone, Os scaphoideum

Type

short

Description

This is the largest of the proximal carpal bones. It is longer than it is wide. The long axis of the bone projects from proximal to distal in line with the second metacarpal bone. Its ventral surface presents a prominent round tubercle at the distolateral end. The grooved dorsal surface contributes to the floor of the anatomical snuff box where a branch of the radial artery crosses over it. A ligament, the dorsal radiocarpal, attaches to this surface. The lateral surface is rough for the attachment of the radial collateral ligament. The distal, proximal, and medial surfaces are smooth articular surfaces.

Etymology

This word literally translates as boat-like. It is from the Greek root skaphe meaning a skiff, boat, bowl, or anything dug-out and suffix eidos meaning form or shape. The bone is so named because of its hollowed out concavity for the reception of a neighboring bone. Synonyms used for this bone throughout anatomical history are the navicular and cotyloid.

Articulations

The scaphoid articulates with five bones: the radius, trapezium, trapezoid, capitate, and lunate. The proximal surface of the bone forms a smooth, convex, triangular facet for articulation with the distal end of the radius. Distally the bone forms a ridge that divides the distal surface into two articular facets. The convex distolateral facet articulates with the trapezium and trapezoid bone, while the large concave distomedial facet articulates with the capitate bone. The medial surface forms a semilunar facet for articulation with the lunate bone.

Ossification

Along with the trapezium and trapezoid bones, the scaphoid ossifies from a single center that arises, on average, during the fourth to fifth year. It usually appears earlier in females versus males.

Latin

Os scaphoideum

Comments

Related Images

View All