Triquetral bone

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Detailed article on the triquetral bone

Location of the triquetral bone (highlighted in red)

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The triquetral bone, also known as the os triquetrum, is one of the eight carpal bones of the wrist. It is situated on the ulnar side of the wrist, proximal to the pisiform bone and distal to the ulna. The triquetral bone is part of the proximal row of carpal bones, which also includes the scaphoid bone, lunate bone, and pisiform bone.

Anatomy

The triquetral bone is a pyramidal-shaped bone that is located in the proximal row of the carpus. It is the third most commonly fractured carpal bone, following the scaphoid and lunate bones.

Surfaces

The triquetral bone has several distinct surfaces:

• Dorsal surface: This surface is rough and serves as an attachment point for ligaments.
• Palmar surface: This surface is also rough and provides attachment for the pisohamate ligament.
• Lateral surface: This surface articulates with the lunate bone.
• Medial surface: This surface articulates with the pisiform bone.
• Distal surface: This surface articulates with the hamate bone.

Articulations

The triquetral bone articulates with three other carpal bones:

• The lunate bone laterally.
• The pisiform bone anteriorly.
• The hamate bone distally.

Function

The triquetral bone plays a crucial role in the complex movements of the wrist. It contributes to the stability and flexibility of the wrist joint, allowing for a wide range of motion. The bone also serves as an attachment point for ligaments that stabilize the carpal bones.

Clinical significance

Fractures

Triquetral fractures are relatively uncommon but can occur due to direct trauma or falls on an outstretched hand. These fractures are often associated with injuries to other carpal bones or ligaments.

Triquetral impingement

Triquetral impingement can occur when the bone is compressed between the ulna and the carpal bones, leading to pain and limited motion.

Development

The triquetral bone ossifies from a single center, which appears between the ages of 9 and 12 years. It is one of the last carpal bones to ossify.

Etymology

The name "triquetral" is derived from the Latin word "triquetrus," meaning "three-cornered," which reflects the bone's pyramidal shape.

Also see

• Carpal bones
• Lunate bone
• Pisiform bone
• Hamate bone
• Scaphoid bone
• Wrist joint