4 The wrist and hand joints Flashcards
What is the wrist joint?
The radiocarpal joint
What type of joint is the radiocarpal joint?
Synovial condyloid joint
What forms the radiocarpal joint?
Proximally - distal end of radius and articular disk
Distally - proximal row of carpal bones except pisiform
Is the ulnar part of the wrist joint?
No due to an articulating disk (fibrocartliaginous ligament) over superior surface of ulna
What type of surface to carpal bones form?
Convex
Does radiocarpal joint have a joint capsule?
Yes, two layers
Fibrous (outer) layer
Synovial membranous (internal) layer
How many signifacnt radiocarpal joint ligaments are there?
4
Palmar radiocarpal
Dorsal radiocarpal
Ulnar collateral
Radial collateral
Where is the palmar radiocarpal ligament?
Palmar (anterior) side of hand, from radius to both rows of carpal bones
What is the purpose of the palmar radiocarpal ligament?
Increase stability of radiocarpal joint
Ensure hand follows forearm in supination
Where is the dorsal radiocarpal ligament?
Dorsal (posterior) side of hand, from radius to both rows of carpal bones
What is the purpose of the dorsal radiocarpal ligament?
Increase stability of radiocarpal joint
Ensure hand follows forearm in pronation
Where is the ulnar collateral ligament?
From styloid process of ulna to triquetrim and pisiform
Where is the radial collateral ligament?
From styloid process of radius to scaphoid and trapezium
What is the purpose of the ulna collateral ligament?
With radial collateral ligament to prevent excessive lateral joint displacement
What is the purpose of the radial collateral ligament?
With ulna collateral ligament to prevent excessive medial joint displacement
Where does the radiocarpal recieve blood branches from?
Dorsal carpal arch
Palmar carpal arch
From radial and ulnar artery
Which nerves are responsible movement of radiocarpal joint?
Posterior interosseus branch of radial nerve
Anterior interosseus branch of median nerve
Deep branch of ulnar nerve
Dorsal branch of ulnar nerve
How many axes can the radiocarpal joint move in?
2
Flexion and extension
Abduction and adduction
Which muscles produce flexion at radiocarpal joint?
Flexor carpi ulnaris
Flexor carpi radialis
Flexor digitorum superficialis (assists)
Which muscles produce extension at radiocarpal joint?
Extensor carpi ulnaris
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor digitorum (assists)
Which muscles produce adduction at radiocarpal joint?
Extensor carpi ulnaris
Flexor carpi ulnaris
Which muscles produce abduction at radiocarpal joint?
Extensor carpi radialis longus
Extensor carpi radialis brevis
Flexor carpi radialis
What are the joints in the hand?
Metacarpophalangeal joints - MCP
Interphalangeal joints - IP
(proximal and distal)
What type of joint is the MCP joint?
Synovial condyloid
What type of joint are IP joints?
Synovial hinge
What are the six movements of the hand?
Flexion of digits
Extension of digits
Abduction of digits
Adduction of digits
Opposition of thumb and little finger
Reposition of thumb and little finger
At which joints can flexion and extension of digits occur?
MCP
PIP
DIP
What is the midline of the hand?
The middle finger
