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Flashcards in Wrist and hand joints Deck (17):

What are the joints of the wrist?

- Radiocarpal
- Intercarpal
- Midcarpal - physiological joint


What are the joints of the hand?

- Carpometacarpal
- Intermetacarpal
- Metacarpophalangeal
- Interphalangeal


What joints are within the wrist complex?

- Radiocarpal: Between distal radius and scaphoid, lunate, triquetrum. It is a condyloid joint
-Intercarpal: Between proximal and distal carpals
- Midcarpal (physiological): Between proximal and distal carpal rows


Describe the wrist joint.

- Condyloid radiocarpal joint.
- Ligamentous support: Medial collateral, Lateral Collateral, Palmar and Dorsal radiocarpa, Palmar and dorsal radioulnar
- Triangular fibrocartilaginous disc
- Blood supply: Branches of palmar and dorsal carpal arches
- Innervation: Anterior/posterior interosseous, deep branch of ulnar


What are the movements at the wrist joint and what muscles control them?

- Flexion: FCR, FCU, FDS, FDP, FPL, PL, APL.
- Extension: ECRL, ECRB, ECU, ED, EI, EDM, EPL. EPB
- Abduction: APL, FCR, ECRL
- Adduction: ECU, FCU


Describe the intercarpal joints.

- Between carpal bones in proximal and distal rows
- Joint capsule is the same as CMC joints
- Ligamentous support: Anterior, posterior, interosseous carpal ligaments
- Blood supply: Palmar and dorsal carpal arches
- Innervation: Anterior interosseous, deep branch of ulna
- Movement: gliding b/w carpals


Describe the midcarpal joints.

- Functional joint
- Convex-concave
- Condyloid tupe
- Movements:Flex/ex and radial deviation to ulnar deviation


What are the joints of the hand?

- Carpometacarpal
- Intermetacarpal
- Metacarpophalangel
- Interphalangeal


CMC and IMC joints.

- Between carpals and metacarpals
- All synovial

- CMC: 2nd + 3rd plane = Immobile; 4th + 5th hinge = Flexion/Extension; 1st saddle = F/E, Ab/Ad, Rotation, Opposition

- IMC = Plane joints

- Ligamentous support: CMC, IMC, Interosseous, Collateral
- Blood supply: Palmar arterial arches, dorsal and palmar metacarpal arteries
- Innervation: Anterior and posterior interosseous, deep ulnar


MCP and IP.

- Fibrous capsule surrounding joints

- MCP: Between head of metacrpal and base of proximal phalanx; condyloid, F/E, Ab/Ad

-IP: Between head of proximal phalanx and base of distal; Hinge, F/E

- Ligamentous support: Collateral ligaments, Transverse metacarpal ligaments, Volar plates, Dorsal Plate, Modified hinge
- Blood Supply: Palmar arterial arch
-Innervation: Median and ulnar nerves


What is skiers thumb?

Rupture of medial collateral ligament from forced abduction and extension


What are the different types of finger injuries?

- Swan-neck deformity = Ventral IP injury (compensatory flexion) or Dorsal IP injury (compensatory hyperextension
- Boutonniere deformity = Dorsal ligament rupture
- Mallet finger = Distal extensor ligament rupture - usually caused by direct blow on extended distal phalanx


Describe the synovial sheaths.

- Common flexor sheath includes tendons of FDS, FDP, FPL
- Digital synovial sheaths
- Fibrous digital sheath

- Sheath for little finger is continuous with ulnar sheath

- Fibrous sheaths are absent where lumbrical muscles attach


What are the fibrous flexor sheaths made of?

- Annular fibres and cruciform fibres
Clinical implications: Spread of infection in synovial sheath - De Quervain's tenosynovitis and digital tenovaginitis stensosans.


What does the Median nerve supply?

- Most muscles of anterior compartment of forearm
- Passes through carpal tunnel
- Also supplies muscles of the thumb
- Supplies skin of lateral 3.5 digits and nail beds

- Susceptible to compression injury in carpal tunnel - disruption to skin and potential motor and sensory loss if injured - Hand of benediction


What does the Ulnar nerve supply?

- Supplies remaining muscles in anterior compartment of forearm and hand except for thumb
- Supplies skin of medial 1.5 digits
- Susceptible to compression and/or stretch across back of medial epicondyle
- Passes superficially to flexor retinaculum
- At wrist, susceptible to compression against handlebar of bike


What does the radial nerve supply?

- Extensor muscles of arm and forearm
- Skin of arm, forearm and back of hand
- Runs across shaft of humerus (between medial/lateral heads of triceps) - susceptible to damage in humeral shaft after fracture or compression - saturday night palsy.