Hand & Wrist Anatomy

The human hand is unique in its dexterity and range of abilities. Our hands hold, move, grasp, feel, and manipulate the world and objects around us. The intricate structure of the hand and wrist allows us to perform everyday tasks with precision and flexibility.

The anatomy of the hand and wrist includes bones, ligaments, tendons, muscles, blood vessels, and nerves. The hand is joined to the arm by the wrist, which consists of eight bones that enable the movement and strength needed to use our hands effectively. Understanding this structure is crucial for both healthcare professionals and those learning about human anatomy.

To gain a deeper understanding of hand and wrist anatomy, our collection of anatomical charts and posters provides clear, detailed illustrations that will enrich your learning experience. Whether you’re a student, lecturer, or healthcare professional, these visual tools can help make complex concepts easier to understand.

The wrist is a condyloid synovial joint. A synovial joint allows for smooth movements between adjacent bones. A condyloid synovial joint is where the joint is more oval in shape, allowing for movement along two axes. This allows for several wide ranges of motion including flexion (up), extension (down), abduction (little finger side of hand moving away from body), and adduction (thumb side of hand moving towards body).

Due to the longer (more distal) ulnar styloid process, abduction is limited. The distal radioulnar joint enables pronation (palm facing down) and supination (palm facing up). The precision of wrist movement is integral to our ability to perform many delicate and skilled actions with our hands.

The thumb and fingers work together to give us a precision grip, similar to that of tweezers, allowing us to pick up small objects or hold a pen in an extremely controlled and delicate way. This precise function is largely thanks to the intricate system of joints and muscles in the hand.

The metacarpal and phalangeal joints (or knuckle joints) allow for flexion and extension. The movement of the thumb is controlled by the carpometacarpal joint, which allows for flexion, extension, abduction, and adduction movements as well as opposition (where the thumb is moved towards the thumb to touch the other fingers) and reposition (where the thumb returns to its anatomical position). The latter two positions are essential for grasping objects with accuracy and strength.

The human hand and wrist consist of 27 bones:

• 8 carpal bones (bones of the wrist)
• 5 metacarpal bones (bones of the palm), and
• 14 phalanges (bones of the fingers and thumb).

The carpal bones join the radius and the ulna of the forearm to the metacarpal bones. The carpal bones are situated in two rows across the wrist. The proximal row is closest to the radius and ulna, and the distal row is closest to the metacarpals. The proximal row consists of the scaphoid, lunate, pisiform, and triquetral. The distal row includes the hamate, capitate, trapezoid, and trapezium. Each small carpal bone forms a joint with the adjacent bone, making the wrist a complex structure composed of numerous smaller joints. These joints work together to provide flexibility and mobility, while maintaining stability during movement.

The proximal articular surfaces of carpal bones are covered with white, shiny, rubbery articular cartilage. This cartilage enables the joint surfaces to move against one another smoothly and absorbs shock, reducing friction and wear. Cartilage is thinner in the wrist joint, which typically doesn’t bear a lot of weight.

The palm is made up of five metacarpal bones, and the phalanges (bones of the fingers) consist of the proximal phalanx, middle phalanx, and distal phalanx.

The muscles in the hand and wrist work together in an incredibly complex fashion. Not only do the muscles give your hand strength, but they also allow for highly controlled and intricate movements. These muscles allow us to perform tasks ranging from gripping heavy objects to writing with precision.

The extrinsic muscles, located in the forearm, help produce a strong grip. The flexor digitorum profundus allows you to bend your index, middle, ring, and little fingers. The flexor pollicis longus allows you to bend the tip of your thumb.

The intrinsic muscles, located in the hand, enable fine motor functions such as writing or threading a needle. These intrinsic muscles consist of four groups: the thenar, hypothenar, interossei, and lumbrical muscles.

The thenar muscles are three muscles located at the base of the thumb. These include the opponens pollicis muscle, which opposes the thumb, the abductor pollicis brevis, which abducts the thumb, and the flexor pollicis brevis, which flexes the thumb.

The hypothenar muscles control the movements of the little finger. These include the opponens digiti minimi, flexor digiti minimi brevis, and abductor digiti minimi.

The interossei muscles are located between the metacarpal bones. The dorsal interossei muscles abduct the fingers at the metacarpophalangeal joints, while the palmar interossei muscles adduct the fingers at the same joints.

The lumbricals are four muscles that attach to the tendons of flexor digitorum profundus. They flex the metacarpophalangeal joints and extend the interphalangeal joints.

Our detailed anatomical hand and wrist models provide a clear visual representation of the bones that form the hand and wrist. These models allow you to better understand joint movement, as well as the muscles and tendons that play a key role in wrist function, making them an ideal learning and teaching tool for students, educators, and healthcare professionals.

The blood vessels in the hand and wrist are vital for transporting oxygen-rich blood to tissues and organs. If you’ve ever been out in the cold without gloves, you may have noticed your fingertips turning a shade of blue. This happens due to the narrowing of blood vessels and reduced blood flow to the fingertips.

Arteries are responsible for carrying oxygen-rich blood from your heart to your tissues. The deep palmar arch extends from the radial artery, wrapping around the thumb and stretching across the palm, supplying blood to the thumb and index finger. The superficial palmar arch, which extends from the ulnar artery, also stretches across the palm.

Nerves are responsible for carrying messages from the hand to the brain for sensation, reflexes, and movement. For example, if you touch a hot stove, the nerves in your finger send a message to your brain, prompting you to react and move your hand away.

There are three major nerves that control hand function: the radial nerve, median nerve, and ulnar nerve.

• The radial nerve is responsible for wrist and finger extension and sensation in the hand. It derives from the C4-T1 nerve fibres of the brachial plexus, transmitting signals from the spinal cord to the shoulder, arm, and hand.
• The median nerve innervates the palmar side of the thumb, index and middle fingers, and the radial side of the ring finger. It originates from the C6-T1 nerve fibres of the brachial plexus.
• The ulnar nerve controls the ring and little fingers, and part of the anterior palm. It originates from the C8 and T1 nerve fibres of the brachial plexus.

Understanding the hand and wrist can be far more effective with high quality visual tools. Our range of anatomical models, posters and study guides allow students and professionals to have a better grasp on the complex anatomy. Whether you're preparing for an exam, teaching a class, or working in a clinical setting, our resources provide a practical and engaging way to study human anatomy.