[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) › Triquetrum [Skeletal system](https://durgical.com/en/anatomy/system/skeletal-system/) · [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) # Triquetrum The triquetrum is a wrist bone on the little-finger side of the first row; after the scaphoid it is the carpal bone most often fractured. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=upper_limb&select=triquetrum&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A pyramid-shaped wrist bone on the little-finger side. ## What it does One of the eight carpal bones that let the wrist bend and carry load to the forearm. ## Key points - Usually the second most fractured carpal bone after the [scaphoid](https://durgical.com/en/anatomy/scaphoid/); most are small dorsal chip fractures after a fall or forced flexion - The dorsal radiocarpal and dorsal intercarpal ligaments both attach to its dorsal ridge, which is why chip avulsions happen there - Linked to the lunate by the lunotriquetral ligament; a tear causes ulnar-sided wrist pain and can lead to VISI ## Key facts **Joints with** Lunate, pisiform, hamate; TFCC **Landmarks** Pyramid shape; facet for the pisiform ## Relations **Lateral** [Lunate](https://durgical.com/en/anatomy/lunate/), joined by the [lunotriquetral ligament](https://durgical.com/en/anatomy/lunotriquetral-ligament/) **Above** [TFCC](https://durgical.com/en/anatomy/triangular-fibrocartilage-complex/) and the [ulnocarpal ligaments](https://durgical.com/en/anatomy/ulnocarpal-ligaments/), which separate it from the ulnar head **Below** [Hamate](https://durgical.com/en/anatomy/hamate/), at a spiral-shaped joint **In front** [Pisiform](https://durgical.com/en/anatomy/pisiform/) on its palmar facet; the [ulnar nerve](https://durgical.com/en/anatomy/ulnar-nerve/) and [ulnar artery](https://durgical.com/en/anatomy/ulnar-artery/) pass close by in Guyon's canal **Behind** Dorsal ridge with the [dorsal radiocarpal ligament](https://durgical.com/en/anatomy/dorsal-radiocarpal-ligament/) and [dorsal intercarpal ligament](https://durgical.com/en/anatomy/dorsal-intercarpal-ligament/) **Medial** Ulnar collateral ligament of the wrist; the ECU tendon passes near it ## How to find it With the wrist in radial deviation it is felt on the back of the little-finger side, just distal to the ulnar styloid process; the pisiform sits on its palmar surface. ## Examination - Lunotriquetral ballottement (shuck) test: the lunate and triquetrum are shifted against each other; pain or excess movement suggests a lunotriquetral ligament injury ## On imaging Dorsal chip fractures often show only on the lateral or an oblique view, as a small flake behind the proximal row; CT if X-rays are unclear. Body fractures are usually part of a perilunate (greater arc) injury. ## Clinical notes - Its upper surface meets the triangular fibrocartilage, not the [ulna](https://durgical.com/en/anatomy/ulna/), so TFCC tears and ulnocarpal impaction load it and cause pain on the little-finger side of the wrist - A dorsal chip fracture is usually treated in a splint and heals well, but tenderness here also raises the question of a lunotriquetral ligament injury ## Anatomical variants - Lunotriquetral coalition (fusion with the lunate), the most frequent carpal coalition, usually painless and seen by chance on X-ray ## Development Ossifies around age 2–3, the third carpal bone to appear. ## Test yourself Think of the answer, then tap the question to see it. ## What is the most common fracture of the triquetrum? A small dorsal chip fracture after a fall or forced flexion; it is usually the second most fractured carpal bone. ## Why do chip avulsions of the triquetrum occur on its dorsal ridge? The dorsal radiocarpal and dorsal intercarpal ligaments both attach there. ## Which test assesses the ligament between the lunate and the triquetrum? The lunotriquetral ballottement (shuck) test: pain or excess movement suggests a lunotriquetral ligament injury. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/anatomy/triquetrum/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** os triquetrum TA2 1253 **Official Spanish (DeCS)** Hueso piramidal **English (TA2)** Triquetrum **Also called** triquetral bone ## Related - [Dorsal intercarpal ligament](https://durgical.com/en/anatomy/dorsal-intercarpal-ligament/) - [Dorsal radiocarpal ligament](https://durgical.com/en/anatomy/dorsal-radiocarpal-ligament/) - [ECU](https://durgical.com/en/anatomy/extensor-carpi-ulnaris/) - [FCU tendon](https://durgical.com/en/anatomy/flexor-carpi-ulnaris-tendon/) - [Flexor retinaculum](https://durgical.com/en/anatomy/flexor-retinaculum/) - [Lunotriquetral ligament](https://durgical.com/en/anatomy/lunotriquetral-ligament/) - [Midcarpal ligaments](https://durgical.com/en/anatomy/midcarpal-and-intercarpal-ligaments/) - [Pisiform ligaments](https://durgical.com/en/anatomy/pisohamate-and-pisometacarpal-ligaments/) Sources: Terminologia Anatomica (TA2); [Anatomy, Shoulder and Upper Limb, Hand Carpal Bones](https://www.ncbi.nlm.nih.gov/books/NBK535382/); [8.2 Bones of the Upper Limb](https://openstax.org/books/anatomy-and-physiology-2e/pages/8-2-bones-of-the-upper-limb) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/triquetrum/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/triquetrum/