5) Hand joints Flashcards
Metacarpals
5 longer bones in the hand
Proximal: Quadrilateral base= articulate distal row carpal bones= carpometacarpal joints
Distal: Rounded head = articulate base proximal phalanx= metacarpalphalangeal
Carpometacarpal joint
Classification
Plane, simple, synoivial, multiaxail
Between carpal and metacarpal bones
Bases of medial 4 metacarpals + medial 3 distal carpal bones
Carpometacarpal joint
Articular surface
see file
Carpometacarpal
joint capsule
see file
Carpometacarpal
synovial membrane
Lines capsule and non articulating margins, attaching to articular margins
Carpometacarpal
ligaments
Dorsal Carpometacarpal ligament
Palmar Carpometacarpal ligament
Interosseous ligament
Dorsal Carpometacarpal ligament
Fibrous bands
Distal row of carpals - Bases of metacarpals
Each metacarpal: x2 bands
Palmar Carpometacarpal ligament
Similar to Dorsal ligament
base of third metacarpal receives 3 bands
Interosseous ligamnet
short
inferior angles of capitate and hamate- base of 3rd/4th metacarpal
Stability Carpometacarpal Joint
very stable providing firm base between joints of wrist and hand
Movement Carpometacarpal joint
slight gliding movement
Flexion and rotation of 5th metacarpal
Intermetacarpals
Plane,simple,synovial, multiaxail
between adjacent sides of bases of:
2nd+3rd
3rd+4th
4th+5th metacarpals
Metacarpalphalangeal joint
Condaloyid, simple , synovial, biaxail
Metacarpalphalangeal
Joint capsule
see file
Metacarpalphalangeal
Articulaing surface
see file
Metacarpalphalangeal
synovial membrane
Lines non-articular surfaces. Anterior+posterior recesses of capsule allow freedom of movement (flexion)
Metacarpalphalangeal
Ligaments
Collateral ligament
Palmar ligament
Deep transverse metacarpal ligament
Metacarpalphalangeal
Collateral Ligament
Strong fan out limit ab and adduction
Passes from:
tubercle on side of metacarpal head —– palmar aspect side of base of proximal phalanx
Palmar Ligament
Dese fibrocartilagionus plate limits extension
firmly attached anterior margin base of proximal phalanx
Acts as amobile articular surface for flexion
Deep transverse metacarpal ligament
Series of short bands connecting palmar ligaments metacarpalphalangeal joints.
Bind 4 medial metacarpals together
Continuous with palmar interosseous fascia fascia blends with flexor sheaths
Metacarpalphalangeal
Stability
Long flexor and extensor tendons
Lumbricals and interossei
Metacarpalphalangeal
movements
Flexion Extension Abduction Adduction Passive rotaton pinky= active rotation
Interphalangeal Joints
Proximal
Distal
Hinge,simple,synovial,uniaxail
Proximal= head of proximal phalanx + base middle phalanx
Distal= head of middle phalanx+ base of distal phalanx
Interphalangeal
Articulating surface
Joint capsule
see file
Interphalangeal
synovial membrane
Lines all non articulating margins including ant+post recesses
Interphalangeal
Ligaments
Collateral ligaments
Palmar ligament
Collateral ligamnet
Interphalangeal
Attatches
sides of the head of most proximal phalanx—–sides of bases of more distal phalanx
tense in flexion
Palmar ligament
Interphalangeal
Mobile fibrocartilaginous plate
Attatched: anterior margin of base of adjacent phalanx
Interphalangeal
Stability
Fairly stable
Interphalangeal
Movement
Flexion
Extension
What’s in the carpal tunnel
Median nerve
Tendons of flexor digitorum superficialis and profundus
Flexor pollicus longus and flexor carpi radialus
Fibrous extensor sheaths of the hand
Tendon sheath = double walled sheath
Encloses tendon
2 layers
Visceral layer= encloses tendon
Parietal layer = outer layer lines surrounding tissue
Cavity between layers contains thin film of synovial fluid
> protects tendon
> friction free movement= through fibroessous tunnels, pass under ligaments and retinaculum
