Scaphoid

Original Editor

Top Contributors - Nina Myburg

Description

The scaphoid is the largest bone of the proximal row of carpal bones.[1] The word scaphoid is derived from the Greek word skaphos which means "a boat". The name refers to the boat-like shape of the bone. Previously it was called the navicular bone (derived from the Latin word navis which means "boat") of the hand. However, there is a tarsal bone in the foot that is also called navicular due to its boat-like shape. The scaphoid is situated at the radial side of the wrist.[2]

Scaphoid bone (animation) - Left hand

Structure

The scaphoid is situated below the radius at the radial (lateral) side of the wrist. It has a boat-like shape with many articulation surfaces. Over 80% of the bone is covered in cartilage. On the palmar surface of the bone, there is a tubercle that can be palpated at the base and medial aspect of the thenar eminence when the hand is extended. [1] It can also be palpated at the base of the anatomical snuffbox.

Scaphoid bone

Function

The scaphoid, together with other carpal bones, provide bony structure to the hand and wrist. It is involved in movement of the wrist together with the lunate and distal surfaces of the radius and ulna. It forms the radial border of the carpal tunnel and serves as attachment site.

Articulations

The scaphoid articulates with five bones:[2]

  • Radius (proximally)
  • Trapezoid and trapezium (distally)
  • Capitate and Lunate (medially)

Soft tissue attachments

  • The transverse carpal ligament attaches to the tubercle of the scaphoid
  • Sometimes a few fibres of abductor pollicis brevis attaches to the tubercle of the scaphoid
  • The radial collateral ligament attaches to the lateral surface

Clinical relevance

Clicking of the scaphoid or no anterior translation can indicate scapholunate instability.

See also

Scaphoid Fracture

Scapholunate Dissociation

Scaphoid shift test

References

  1. 1.0 1.1 Moore KL, Dalley AF. Clinically Oriented Anatomy. Fifth edition. Philadelphia: Lippincot Williams & Wilkins; 2006
  2. 2.0 2.1 Gray H. Anatomy of the Human Body. Twentieth edition. Philadelphia: Lea & Febiger; 1918 Available from: https://www.bartleby.com/107/54.html [Accessed 19 June 2019]