Scaphoid

Changed by Daniel J Bell, 15 Apr 2024
Back to revision history
Disclosures - updated 22 Aug 2023: Nothing to disclose

Updates to Article Attributes

Body was changed:

The scaphoid, also known as the os scaphoideum (or historically as the navicular),is the largest of the proximal row of carpal bones and forms the radial portion of the carpal tunnel. It is important for stability and movement at the wrist and may be fractured after a fall onto a hyperextended hand. Scaphoid fractures may be radiologically occult in the acute setting and may result in osteonecrosis. 

Gross anatomy

Osteology

The scaphoid is the largest of the proximal row of carpal bones and sits on the radial side of the lunate. It is a boat-shaped bone that is orientated obliquely with its long axis aligned from the medial portion of the distal radius proximally to the articulation of the 1st and 2nd metacarpals distally.

The scaphoid can be divided into proximal and distal poles. The waist (between the two) is the commonest site of scaphoid fracture. The scaphoid tubercle is a bony prominence on the ventral surface of the lateral portion of the distal pole.

Articulations

The scaphoid articulates with five bones: the radius, trapezoid, trapezium, lunate and capitate.

Proximally, the smooth convex surface of the scaphoid articulates with the distal radius.

The distal surface is split into two separate articular surfaces by a bony ridge. On the radial side it articulates with the trapezoid and trapezium while on the ulnar side it articulates with the capitate.

The medial surface has a smooth concave surface and articulates with the lunate.

Attachments
Musculotendinous

There are no musculotendinous attachments to the scaphoid bone.

Ligamentous
Relations

The radial artery crosses the dorsal surface of the scaphoid.

The scaphoid forms the radial portion of the carpal tunnel and is therefore related to the structures that pass through it, namely fibres from flexor digitorum profundus and superficialis, the median nerve, flexor pollicis longus and flexor carpi radialis.

Also located in the vicinity are the muscles of the thumb and associated tendons.

Arterial supply

Approximately 75% of the arterial supply is from branches of the radial artery through vascular perforations on the dorsal surface near the tubercle and waist 2. As the vascular supply to the proximal pole is mainly retrograde, a fracture through the tubercle or the waist places the proximal pole at risk of avascular necrosis.8

Variant anatomy

Radiographic features

Plain radiograph

The scaphoid is the most radial of the proximal row of carpals, articulating with the distal radius, lunate and capitate. On the lateral view, it is projected through the carpus.

The scaphoid may be visualised on a number of series of the distal upper limb including:

Development

Ossification

The scaphoid has a single ossification centre, as do the trapezoid and trapezium. Ossification begins around the 5th year, and completes at 13-15 years of age 7. As with most ossification in the hand and wrist, it tends to occur earlier in females.

History and etymology

The termScaphoid means boat-shaped and derives from the Ancient Greek word σκαφη (skaphe) meaning boat 6. Indeed, historically an alternative name for the 'os scaphoideum' was the 'os naviculare manus', meaning navicular bone of the hand. This is not that surprising as navicular is the Latin for boat-shaped. It was decided by anatomists in 1955 to use navicular solely for the foot and scaphoid for the hand, as detailed in the Parisiensia Nomina Anatomica, one of the forerunners of the Terminologia Anatomica9.

Related pathology

  • -</ul><h4>Development</h4><h5>Ossification</h5><p>The scaphoid has a single ossification centre, as do the trapezoid and trapezium. Ossification begins around the 5<sup>th</sup> year, and completes at 13-15 years of age <sup>7</sup>. As with most ossification in the hand and wrist, it tends to occur earlier in females.</p><h4>History and etymology</h4><p>The term derives from the Ancient Greek word σκαφη&nbsp;(skaphe) meaning boat <sup>6</sup><em>.</em></p><h4>Related pathology</h4><ul>
  • +</ul><h4>Development</h4><h5>Ossification</h5><p>The scaphoid has a single ossification centre, as do the <a href="/articles/trapezoid" title="Trapezoid">trapezoid</a> and <a href="/articles/trapezium" title="Trapezium">trapezium</a>. Ossification begins around the 5<sup>th</sup> year, and completes at 13-15 years of age <sup>7</sup>. As with most ossification in the hand and wrist, it tends to occur earlier in females.</p><h4>History and etymology</h4><p>Scaphoid means boat-shaped and derives from the Ancient Greek word σκαφη&nbsp;(skaphe) meaning boat <sup>6</sup>. Indeed, historically an alternative name for the 'os scaphoideum' was the 'os naviculare manus', meaning navicular bone of the hand. This is not that surprising as navicular is the Latin for boat-shaped. It was decided by anatomists in 1955 to use navicular solely for the foot and scaphoid for the hand, as detailed in the Parisiensia Nomina Anatomica, one of the forerunners of the <a href="/articles/terminologia-anatomica-1" title="Terminologia Anatomica">Terminologia Anatomica</a> <sup>9</sup>.</p><h4>Related pathology</h4><ul>

References changed:

  • 9. FIPAT. Terminologia Anatomica. 2nd Ed. FIPAT.library.dal.ca. Federative International Programme for Anatomical Terminology, 2019. <a href="https://fipat.library.dal.ca/TA2/">https://fipat.library.dal.ca/TA2/</a>

Updates to Synonym Attributes

Title was added:
Os naviculare manus
Slug was set to os-naviculare-manus.
Type was set to Synonym.
Visible was set to true.
Content Type was set to Article.

Updates to Synonym Attributes

Title was added:
Scaphoids
Slug was set to scaphoids.
Type was set to Synonym.
Visible was set to false.
Content Type was set to Article.

ADVERTISEMENT: Supporters see fewer/no ads