![]() The scaphoid may be visualized on a number of series of the distal upper limb including: The term derives from the Ancient Greek word σκαφη (skaphe) meaning boat 6. As with most ossification in the hand and wrist, it tends to occur earlier in females. Ossification begins around the 5 th year, and completes at 13 to 15 years of age 7. The scaphoid has a single ossification center, as do the trapezoid and trapezium. ![]() On the lateral view, it is projected through the carpus. The scaphoid is the most radial of the proximal row of carpals, articulating with the distal radius, lunate and capitate. Scaphoid hypoplasia (as long as not associated with other skeletal dysplasias) 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. Arterial supplyĪpproximately 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. The scaphoid forms the radial portion of the carpal tunnel and is therefore related to the structures that pass through it, namely fibers from flexor digitorum profundus and superficialis, the median nerve, flexor pollicis longus and flexor carpi radialis.Īlso located in the vicinity are the muscles of the thumb and associated tendons. The radial artery crosses the dorsal surface of the scaphoid. Radial surface: radial collateral ligament Ligamentousĭorsal surface: dorsal radiocarpal ligament There are no musculotendinous attachments to the scaphoid bone. The medial surface has a smooth concave surface and articulates with the lunate. On the radial side it articulates with the trapezoid and trapezium while on the ulnar side it articulates with the capitate. The distal surface is split into two separate articular surfaces by a bony ridge. Proximally, the smooth convex surface of the scaphoid articulates with the distal radius. The scaphoid articulates with five bones: the radius, trapezoid, trapezium, lunate and capitate.ĭistal surface: laterally with the trapezoid and trapezium medially with the capitate The scaphoid tubercle is a bony prominence on the ventral surface of the lateral portion of the distal pole. The waist (between the two) is the commonest site of scaphoid fracture. The scaphoid can be divided into proximal and distal poles. It is a boat-shaped bone that is oriented obliquely with its long axis aligned from the medial portion of the distal radius proximally to the articulation of the 1 st and 2 nd metacarpals distally. The scaphoid is the largest of the proximal row of carpal bones and sits on the radial side of the lunate.
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