Hand, Carpus Flashcards
movements of the wrist
abduction adduction extension flexion radial deviation ulnar deviation
joints of the wrist
Radiocarpal joint Midcarpal Plane joints between individual small bones Carpo-metacarpal joints 2-5 Carpo-metacarpal joint of the thumb (first carpo-metacarpal joint)
contents of radiocarpal joint and the type of joint (including its no. axes)
Synovial joint between radius & proximal carpal row Articular disc Ellipsoid (condyloid) 2 axes + circumduction
capsule of the radiocarpal joint attaches to..
at distal radius & ulna and around proximal carpal
bones
ligaments that strengthen the capsule
- Palmar and dorsal ligaments
- Radial & ulnar collateral lig.
what type of joint is the first carp-metacarpal joint and in what direction does it move
saddle joint
2 axes
most common carpal bone fracture
scaphoid fracture
what percentage of scaphoid fractures cause absence of nutrients via supply?
what does this lead to?
13%
avascular necrosis
lunate dislocation
separation of the lunate from both
the capitate and the radius.
cause of lunate dislocation
from excessive pressure on to a
hyperextended wrist.
• e.g. a fall on an outstretched hand or
occur in a motor vehicle crash.
dislocation of lunate carpal bones will effect which nerve
median nerve
location of bennets fracture
First CMC (carpometacarpal) joint Affects base of 1st metacarpal
causes of bennets fracture
Caused by excessive abduction of 1st metacarpal
bennets fracture
small fragment of 1st metacarpal, attached to anterior oblique ligament, continues to articulate with trapezium
metacarpal phalangeal joint
location
type of joint
movement
metacarpal joint
ellipsoid joint - 2 axes
extension/flexion
abduction/adduction
type of joint of a interphalangeal joint
hinge joint
hand layers
skin and subcutis deep fascia/palmar aponeurosis superficial muscle layer palmar spaces deep muscle layer - adductor pollicis muscle, interossei
shape of palmar aponeurosis
triangular shape Apex of triangle is proximal • Anchored to flexor retinaculum • Palmaris longus divides into slips
tendons and sheaths in palmar aponeurosis
• Fibrous flexor tendon sheaths
• Deep transverse metacarpal ligaments -
Across MC heads & MCP joints
thenar eminence
Short muscles of the thumb
attachment of thenar eminence
Attached to radial side of flexor
retinaculum & adjacent carpal bones
innervation of thenar eminence
median nerve
hypothenar eminence
Short muscles of the little finger
attachment of hypothenar eminence
Attached to ulnar side of flexor
retinaculum & adjacent carpal bones
innervation of hypothenar muscle
Ulnar nerve
name the 3 thenar muscles
Opponens Pollicis (1st MC)
Abductor Pollicis Brevis (PP)
Flexor Pollicis Brevis (PP)
muscles of the hypothenar muscles
Opponens Digiti Minimi (5th MC)
Abductor Digiti Minimi (PP)
Flexor Digiti Minimi (PP)
content of carpal tunnel
tendons of; flexor digitorum profundus flexor digitorum superficialis flexor pollicis longus median nerve
compression of tunnel contents leads to
Median Nerve palsy
distal to the wrist
Thenar muscle wasting
Absence of opposition of the thumb
causes of carpal tunnel syndrome
Fluid retention cardiac, renal, pregnancy Tendonitis of the long flexors Bone overgrowth Arthritis
treatment for carpal tunnel syndrome
divide flexor retinaculum
guyon space
ulnar artery and nerve
palmar carpal ligament
flexor retinaculum
long flexor tendons
Flexor digitorum superficialis (PIP joints)
Flexor digitorum profundus (DIP joints)
Flexor pollicis longus (IP joint)
fibrous tendon sheaths function
Prevent Bowstringing of tendons
• Annular and Cruciate Pulleys
synovial flexor tendon sheaths function
reduce friction
lumbricals arise from
Flexor Digitorum Profundus
where do the lumbricals pass
Pass on radial side of MCP joint to insert
into extensor hood
function of lumbricals
Flex MCP & extend IP joints
innervation of lateral lumbricals
Median nerve (digital branch) Unipennate
innervation of medial lumbricals
Ulnar nerve (deep branch) Bipennate
palmar spaces
medial fibrous septum
midpalmar space
lateral fibrous septum
thenar space
origin of adductor pollicis
Transverse head – shaft of 3rd MC
Oblique head – 2nd / 3rd MCs and capitate
insertion of adductor pollicis
Ulnar aspect PP of the thumb
action of adductor pollicis
adduction
innervation of adductor pollicis
ulnar nerve
muscle type of palmar interossei
insertion and origin
unipennate
on palmar surface 1-5 MC
action of palmar interossei
adduction
long axis of middle finger
dorsal interossei origin
Bipennate (attach to 2 metacarpals)
insertion of dorsal interossei
Into extensor expansions
2nd, 3rd & 4th digits (3rd has 2)
innervation of dorsal interossei
Ulnar nerve
action of dorsal interossei
abduction
Dorsal interossei abduct (DAB)
interconnected networks of the arterial supply of the hand
Superficial palmar arch
Deep palmar arch
Dorsal network
radial artery locations
Lateral to Flexor Carpi Radialis
Runs posteriorly
Anatomical snuff box
where does the radial artery run anteriorly to
through webspace
Through 1st dorsal interosseus
Through Adductor Pollicis
ulnar artery direction
Runs superficial to flexor retinaculum
Guyon’s canal
Deep branch to deep arch
causes of klumpkes paralysis
Lower brachial plexus injury
Paralysis of C8 / T1
signs of klumpkes paralysis
Small muscles of hand - claw Unopposed action of long flexors & extensors Flexes PIP & DIP joints - extends MCP joints
distal injury of ulnar nerve leads to
paralysis of:
• Interossei
• 2 medial lumbricals
• Hypothenar muscles
distal injury of deformity of ulnar nerve leads to
deformity
• “Claw hand”
• Maximal in medial (ulnar) 2 digits
• Extension of MCPs & flexion of IPs
proximal injury of ulnar nerves causes
“Ulnar Paradox”
• Due to partial paralysis of FDP
injury of median nerve leads to paralysis of
- 2 radial / lateral Lumbricals
- Thenar muscles (OAF)
- Test opposition
injury of median nerve leads to deformity of
Ape hand / pointing finger
distal injury of median injury
carpal tunnel syndrome
proximal injury of median
FDP/FDS - increased digital extension
