As of the latest update, Google Chrome and Microsoft Edge have made a breaking change to how file uploads are handled. Once your system installs this update, you will not be able to upload new images. Please use another browser until we can get it fixed.


The triquetrum (also known as os triquetrum or triangular bone) is one of the carpal bones and forms part of the proximal carpal row.

The triquetrum is wedge-shaped carpal bone located between the lunate and the pisiform. It has an oval facet for articulation with the pisiform.

  • along with the scaphoid and lunate, forms the distal articular surface of the radiocarpal joint
  • intercarpal articulations
  • a meniscus attached to the triquetrum is located between the radiocarpal and pisiform-triquetral compartments
  • nil
  • receives its blood supply from a network of nutrient vessels on both non-articular surfaces
  • frontal projection (neutral wrist position)
  • Norgaard view
    • better for evaluating the triquetral-pisiform articulation than the frontal or lateral view

Cartilaginous at birth, triquetral ossification typically begins at age three and is complete by age six or seven 2. The triquetral ossification center often precedes the lunate 1

From the Latin "triquetrus" meaning "having three corners". It was originally termed the "cuneiform" bone, when named by Lyser in 1653. It was first called the "triquetrum" by Albinus in 1726.

Anatomy: Upper limb

Anatomy: Upper limb

Share article

Article information

rID: 33146
Section: Anatomy
Synonyms or Alternate Spellings:
  • Triangular bone
  • Triquetral bone
  • Os triquetrum

Support Radiopaedia and see fewer ads

Cases and figures

  • Figure 1: carpal bones
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.