Premium Nahrungsergänzungsmittel | artgerecht

Os Triquetrum – Anatomy, Function & Injuries

The os triquetrum is a small carpal bone located on the ulnar side of the wrist. It belongs to the proximal carpal row and plays a key role in wrist stability and movement.

Regular tips about health Regular tips about health

Things worth knowing about "Os triquetrum"

The os triquetrum is a small carpal bone located on the ulnar side of the wrist. It belongs to the proximal carpal row and plays a key role in wrist stability and movement.

What is the Os triquetrum?

The os triquetrum (also known as the triquetral bone or os triquetrale) is one of the eight carpal bones that make up the wrist. It is situated in the proximal carpal row on the ulnar side, meaning the side of the little finger. Its name derives from the Latin word triquetrus, meaning triangular, referring to its distinctive three-sided shape. The bone articulates with the lunate, the pisiform, and the hamate, and is indirectly connected to the ulna via the triangular fibrocartilage complex (TFCC).

Anatomy and Location

The os triquetrum is positioned between the lunate bone on the radial side and the pisiform bone on the palmar side. It forms a critical part of the proximal carpal row and is tightly connected to neighboring bones by strong ligaments. Its ulnar position makes it an important stabilizer of the ulnocarpal joint.

Joint Connections

Lunate bone: medial articular surface
Pisiform bone: palmar articular surface
Hamate bone: distal articular surface
Ulna: indirect connection via the TFCC

Function

The os triquetrum fulfills several important functions within the wrist joint:

Participation in flexion and extension of the wrist
Participation in ulnar deviation (bending toward the little finger side)
Stabilization of the ulnocarpal joint
Transmission of forces from the hand to the forearm bones

Common Injuries and Conditions

Triquetrum Fracture

A triquetrum fracture is the second most common carpal fracture after the scaphoid fracture. It typically results from a fall onto an outstretched hand or from direct trauma. Two main types are recognized:

Dorsal avulsion fracture: The most common type, in which a small bony fragment is pulled off the dorsal surface of the bone.
Body fracture: Less common, involves the entire bone body and is often associated with other carpal injuries.

Symptoms of a Triquetrum Fracture

Pain on the ulnar (little finger) side of the wrist
Swelling and tenderness over the triquetrum
Restricted wrist range of motion
Increased pain during ulnar deviation

Other Conditions

Ligamentous instability: Injuries to the lunotriquetral ligaments can lead to wrist instability.
Osteoarthritis: Degenerative changes of the triquetrum as part of carpal osteoarthritis.
Os triquetrum bipartitum: A rare anatomical variant in which the triquetral bone consists of two separate bony segments.

Diagnosis

Several imaging techniques are used to evaluate injuries of the os triquetrum:

X-ray: Standard first-line imaging; dorsal avulsion fractures are typically visible on a lateral view.
Computed tomography (CT): Provides detailed visualization of fracture patterns and joint involvement.
Magnetic resonance imaging (MRI): Particularly useful for assessing ligament injuries and occult (hidden) fractures.

Treatment

Conservative Treatment

Most triquetrum fractures, especially dorsal avulsion fractures, respond well to conservative management:

Immobilization of the wrist in a plaster or synthetic cast for 4 to 6 weeks
Pain management with anti-inflammatory medications
Physiotherapy to restore strength and range of motion after healing

Surgical Treatment

In cases of complex fractures, instability, or non-union, surgical intervention may be required:

Osteosynthesis (fixation of bone fragments using screws or wires)
Ligament reconstruction for cases of ligamentous instability

References

Standring, S. (Ed.) - Gray's Anatomy: The Anatomical Basis of Clinical Practice. 41st Edition. Elsevier, 2015.
Mayfield, J.K. et al. - Carpal dislocations: pathomechanics and progressive perilunar instability. Journal of Hand Surgery, 1980; 5(3):226-241.
Amadio, P.C. & Taleisnik, J. - Fractures of the carpal bones. In: Green's Operative Hand Surgery. 6th Edition. Churchill Livingstone, 2011.

Building Blocks for a Healthy Life

As an integrated manufacturer, we develop & produce evidence-based, patented, and non-patented formulations. We work exclusively with plant and natural extracts according to the strictest purity & quality standards.
The combination of science & modern technology with the laws of nature creates solutions consistently tailored to humans – for the highest good: health.

Most read entries

3 Posts in this encyclopedia category