Pisiform bone
Encyclopedia
The pisiform bone is a small knobbly, pea-shaped wrist
bone.
The pisiform bone is found in the proximal row of the carpus
. It is located where the ulna
(inner bone of the forearm when in anatomical position) joins the carpus
(wrist). It articulates only with the triquetral.
It is a sesamoid bone
.
The pisiform bone may be known by its small size, and by its presenting a single articular facet. It is situated on a plane anterior to the other carpal bones and is spheroidal in form.
The etymology derives from the Latin pīsum which means "pea."
The palmar surface is rounded and rough, and gives attachment to the transverse carpal ligament, and to the Flexor carpi ulnaris and Abductor digiti quinti.
The lateral and medial surfaces are also rough, the former being concave, the latter usually convex.
Wrist
In human anatomy, the wrist is variously defined as 1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand;...
bone.
The pisiform bone is found in the proximal row of the carpus
Carpus
In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers , whereas those of the metacarpus do. The corresponding part of the foot is the tarsus...
. It is located where the ulna
Ulna
The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...
(inner bone of the forearm when in anatomical position) joins the carpus
Carpus
In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers , whereas those of the metacarpus do. The corresponding part of the foot is the tarsus...
(wrist). It articulates only with the triquetral.
It is a sesamoid bone
Sesamoid bone
In anatomy, a sesamoid bone is a bone embedded within a tendon.Sesamoids are found in locations where a tendon passes over a joint, such as the hand, knee, and foot. Functionally, they act to protect the tendon and to increase its mechanical effect. The presence of the sesamoid bone holds the...
.
The pisiform bone may be known by its small size, and by its presenting a single articular facet. It is situated on a plane anterior to the other carpal bones and is spheroidal in form.
The etymology derives from the Latin pīsum which means "pea."
Surfaces
Its dorsal surface presents a smooth, oval facet, for articulation with the triquetral: this facet approaches the superior, but not the inferior border of the bone.The palmar surface is rounded and rough, and gives attachment to the transverse carpal ligament, and to the Flexor carpi ulnaris and Abductor digiti quinti.
The lateral and medial surfaces are also rough, the former being concave, the latter usually convex.
See also
- Intercarpal articulations
- Bone terminology
- Terms for anatomical location
