The bones of the hand provide support and flexibility to the soft tissues. They can be divided into three categories: Show
In this article, we shall look at the anatomical features of the bones of the hand. By TeachMeSeries Ltd (2022)  Fig 1 – Overview of the bones of the hand. Carpal BonesThe carpal bones are a group of eight, irregularly shaped bones. They are organised into two rows: proximal and distal. Proximal Row (lateral to medial)Distal Row (lateral to medial)
Collectively, the carpal bones form an arch in the coronal plane. A membranous band, the flexor retinaculum, spans between the medial and lateral edges of the arch, forming the carpal tunnel. Proximally, the scaphoid and lunate articulate with the radius to form the wrist joint (also known as the ‘radio-carpal joint’). In the distal row, all of the carpal bones articulate with the metacarpals. By TeachMeSeries Ltd (2022) Fig 2 – Palmar view of the carpal bones of the left hand. By TeachMeSeries Ltd (2022) Fig 3 – Transverse section of the carpal tunnel. Clinical Relevance: Scaphoid FractureThe scaphoid bone of the hand is the most commonly fractured carpal bone – typically by falling on an outstretched hand (FOOSH). In a fracture of the scaphoid, the characteristic clinical feature is pain and tenderness in the anatomical snuffbox. The scaphoid is at particular risk of avascular necrosis after fracture because of its so-called ‘retrograde blood supply’ which enters at its distal end. This means that a fracture to the middle (or ‘waist’) of the scaphoid may interrupt the blood supply to the proximal part of the scaphoid bone rendering it avascular. Patients with a missed scaphoid fracture are likely to develop osteoarthritis of the wrist in later life. By Gilo1969 (Own work) [CC-BY-SA-3.0], via Wikimedia Commons Fig 4 – Radiograph of a scaphoid fracture. Adapted from work by Iiibalesiii [CC BY-SA 4.0] Fig 5 – The blood supply to the scaphoid bone runs from distal to proximal. Metacarpal BonesThe metacarpal bones articulate proximally with the carpals, and distally with the proximal phalanges. They are numbered, and each associated with a digit:
Each metacarpal consists of a base, shaft and a head. The medial and lateral surfaces of the metacarpals are concave, allowing attachment of the interossei muscles. Clinical Relevance: Fractures of the MetacarpalsThere are two common fractures of the metacarpals:
By TeachMeSeries Ltd (2022) Fig 6 – Bennett’s fracture. PhalangesThe phalanges are the bones of the fingers. The thumb has a proximal and distal phalanx, while the rest of the digits have proximal, middle and distal phalanges. What are the 7 bones of the wrist?Wrist Bones. Scaphoid. The scaphoid is a bone in the wrist. ... . Lunate. The lunate is a bone in the middle of the wrist in the first row of wrist bones. ... . Triquetrum. The triquetrum is a bone on the small finger side of the wrist in the first row of wrist bones. ... . Trapezoid. ... . Trapezium. ... . Capitate. ... . Hamate. ... . Pisiform.. How many bones are in the hand and wrist?Bones. The human hand has 27 bones: the carpals or wrist accounts for 8; the metacarpals or palm contains five; the remaining fourteen are digital bones; fingers and thumb. The palm has five bones known as metacarpal bones, one to each of the 5 digits.
What are the 2 bones in your wrist?The Radius is a long and thicker bone that is located on the thumb side of the wrist. The Ulna is a long but thinner bone that is located on the pinky side of the wrist. These 2 bones connect to the bones in the hand, known as the carpal bones, to make up the wrist.
What are the 5 hand bones?The proximal row of carpal bones (moving from radial to ulnar) are the scaphoid, lunate, triquetrum, and pisiform, while the distal row of carpal bones (also from radial to ulnar) comprises the trapezium, trapezoid, capitate, and hamate.
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Identify the bones of the wrist and hand
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