Exam 4 Flashcards
what is the primary goal of elbow and FA
placement of hand
what connects on the med epicondyle
common flexors/pronators
what connects on the lat epicondyle
common extensor/supinators
describe the proximal ulna
thick
olecranon process
trochlear notch
radial notch
describe the distal ulna
articular cartilage
styloid process
what attaches to the supinator crest
LCL and sup mm
what attaches to the tuberosity of the ulna
brachialis
how is the radius positioned in supination
parallel and lateral
describe the distal end of radius
large
styloid process
describe the proximal end of radius
small
radial head
fovea
describe radial head
disc like articular cartilage
280 deg of rim
radial notch on ulna
what is the fovea on the radial head
shallow up connected to capitulum
describe the humeral-ulnar jt
FLX/EXT
stability
describe the humeroradial jt
FLX/EXT
ligaments attach to radial head and capitulum
what is the normal cubitus valgus
carrying angle
13 deg
excessive = 20-25 deg
describe the capsule/ligaments of the elbow
encompass 3 jts
multiplanar stability
describe the ant fibers of MCL
strongest
resist valgus
med epicondyle to coronoid process
stability in sagittal
describe the post fibers of MCL
posterior/med capsule
med epicondyle to olecranon
resist valgus
tight in flexion
describe the transverse fibers of the MCL
olecranon to coronoid process
articular stability
what is a WB injury to MCL
extended/valgus force
compression fx
ant capsule
med muscles at epicondyle
what is a NWB injury to MCL
repetitive valgus force (overhead athletes)
ant fibers damaged - tommy john surgery
what is the RCL
annular lig
supinator
extensor carpi radialis brevis
what is the LCL
thicker
taut at full flexion
sling for radial head
frontal/horizontal plane stability
what is a triad injury in the elbow
full outstretch supinated
elbow jt dislocation
fx radial head
fx coronoid process
what are complications of the triad injury
persistent instability
n damage
stiffness
what level of spinal injury can cause paralysis in elbow
above C5 spinal injury
what is a flexion contracture
after immobilization
ossification
inflammation
m spasticity
tricep paralysis
scarring
what is the functional arc of elbow
145-150
what are the humero-ulnar jt arthro
concave trochlear notch on convex trochlea
what fibers are taut in full elbow extension
anterior m and tissues
ant capsule
ant MCL fibers
what fibers are taut in FLX
elongation of ulanr n
post capsule and m
post MCL fibers
what are the humeroradial arthro
radius rolls and slides
cuplike fovea and capitulum
what is the fovea doing in active FLX
firmly against capitulum
how is the central band of interosseus membrane positioned
directed distally medially at 20 deg from radius
what are complications of interosseus membrane tears
proximal migration of radius
Describe the proximal radio-ulnar jt
Radial notch + annular ligament
Lined with cartilage
Attachment for radial collateral and supination m
Describe the distal radio-ulnar jt
Convex head of ulna
Shallow concavity on radius
TFC, disc, m
What is the TFC
Triangular fibrocartilage
Holds the ulna head to the notch during supination and pronation
What are the stabilizers of the distal radio-ulnar jt
TFCC, pronator quadratus, ECU, interosseus membrane
What limits supination
Pronator teres
Pronator quadratus
Flexor carpi radialis
TFCC
quadrate lig
Interosseus membrane
what limits pronation
biceps
supinator
radial wrist extensors
extensor pollicis longus
TFCC
how do the bones move during supination at the proximal and distal seg
radius and carpal bones rotate around fixed humerus and ulna
prox- radial head RT
distal- radius rolls and slides same direction
where is the axis of RT in the radio-ulnar jt
nearly parallel to the interosseus membrane
limits tension
stabilizer
what is happening in pronation in open chain activities
pronator rotates the radius around fixed ulna
what is happening in pronation in closed chain activities
the infraspinatus rotates the humerus relative to fixed scapula
ER of ulna around fixed radius
what are the elbow flexors
brachialis (MSC n)
bicep brachii (MSC n)
brachioradialis (radial n)
pronator teres (median n)
what are the elbow extensors
tricep brachii (radial n)
anconeus (radial n)
what are the FA pronators
pronator quadratus (median n)
pronator teres (median n)
what are the FA supinators
bicep brachii (MSC n)
supinator (radial n)
what is the job of the 3 heads of tricep
medial - workhorse
lateral - mod to high levels of demand
long - reserve for high performance
when does the tricep have max torque
80-90 elbow flexion
what does the tricep do in WB
stability as isometric or low velocity eccentric
when does the tricep do high velocity concentric
sports
pushing up from a chair
pushing up from door
what are the secondary supinator m
radial wrist extensors
extensor pollicis longus
extensor indicis
brachioradialis
when is the bicep recruited for supination
90 deg elbow flexion
where does the median n pass through
2 heads of pronator teres
what is an effect of median n injury
pronators are paralyzed
what are secondary pronators
flexor carpi radialis
palmaris longus
brachioradialis
what is different from carpul tunnel syndrome and pronator teres syndrome
pronator teres has pain in medial FA plus the paresthesia on palmar 3.5 digits
what is the ulna tilt
distal end of radius tilts towards ulna 25 deg
what is the palmar tilt
ulna is 10 deg more in flexion than wrist ext
what makes up the prox carpal row
scaphoid, lunate, triquetrum, and pisiform
loosely joined
what makes up the distal carpal row
trapezium, trapezoid, capitate, and hamate
bound tightly by ligaments
describe the scaphoid
undersurface of radius
holds head of capitate
lined with articular cartilage
synovial jt with 4 other carpals
what is the mostly fx carpal
scaphoid
what is kienbocks disease
softening of lunate- AVN
describe the lunate
moon shaped
central bone of prox row
most unstable
describe the triquetrum
triangular bone
most ulnar
articular facet that accepts pisiform
describe the pisiform
shaped like a pea
articulates with triquetrum
embedded in FCU
acts like sesamoid bone
attachment for ABD DM, transverse carpal lig
describe the capitate
largest, central
articulates with 7 bones
stable
axis through captitate
describe the trapezium
asymmetrical
concave at scaphoid
distal saddle
tubercle is attachment for transverse carpal lig
FCR groove
describe the trapezoid
small
between capitate and trapezium
firm attachment to 2nd metacarpal
describe the hamate
large hook
at 4/5th metacarpal
functional mobility- cupped hand
attachment of transverse lig
what makes the carpal tunnel
transverse carpal lig
what are the attachments for transverse carpal lig
pisiform, hook of hamate, tubercle of trapezium and scaphoid
describe the radiocarpal jt
concave radius and convex scaphoid and lunate
greatest contact at slight ext and ulnar dev (triquetrum is apart of it)
describe the midcarpal jt
between prox and distal rows
lat and med compartment
how many joints are in the intercarpal jt
13
how many DOF are within the wrist
2
sagittal and frontal plane
what is the degrees of sagittal plane
FLX- 0-70/85
EXT- 0-60/75
what is the degrees of frontal plane
R dev- 0-50/60
U dev- 0-35/40
what are functional ranges for ADLS
40 deg FLX/EXT
10 deg R dev
30 deg U dev
what is the position of function for wrist
10-15 deg EXT
10 deg U dev
what are the motion combos of the wrist
EXT occurs with R dev
FLX occurs with U dev
what is the central column
formed by linkages between radius and lunate, med compartment of midcarpal jt
describe the arthro of wrist EXT
concave on convex
lunate rolls dorsally and slides palmarly
capitate rolls dorsally and slides palmarly on lunate
closed packed position in wrist EXT
describe the arthro of wrist FLX
lunate rolls palmar and slides dorsal
capitate rolls palmar and slides dorsal on lunate
describe the arthro of R dev
prox row rolls radially and slides ulnar
capitate rolls radially and slides ulnar
carpals run into radius
describe the arthro of U dev
prox row rolls ulnarly and slides radially
capitate rolls ulnarly and slides radially
MC jt has most motion
what do the prox row of carpals do with R dev
scaphoid and lunate rock into FLX
what carpal is most likely dislocated
lunate
what m are innervated by the radial n
ECRB
ECRL
ECU
what m is innervated by the ulnar n
FCU
what m are innervated by the median n
FCR
Palmaris longus
what is the sensory innervation of RC
C6-7
what is the sensory innervation of MC
C6-8
what are the primary wrist EXT that act only on the wrist
ECRL
ECRB
ECU
what are the secondary wrist EXT that act on wrist and hand
ED
EXT indicis
EDM
EPL
what is in compartment 1
extensor pollicis brevis
abd pollicis longus
what is in compartment 2
ECRL
ECRB
what is in compartment 3
extensor pollicis longus
what is in compartment 4
ED
extensor indicis
what is in compartment 5
EDM
what is in compartment 6
ECU
what are the primary wrist fLX
FCR
FCU
PL
palmar carpal lig
what are the secondary wrist FLX
FDP
FDS
FPL
ABD PL
what m has the greatest torque for wrist FLX
FCU
what mm work together as synergists for wrist deviations
FCR and FCU
what motion is able to produce more isometric torque, wrist FLX or EXT
wrist FLX
what is peak wrist fLX torque
40 deg
what is peak wrist EXT torque
30-70 deg
what mm produce R dev
ECRB
ECRL
ABD PL
EPL
EPB
FCR
FPL
what mm produce U dev
ECU
FCU
FDP
FDS
ED
describe the arches of the hans
natural concavity allows for control
What are the arches of the hand
proximal transverse
distal transverse
longitudinal
what is the proximal transverse arch
formed by distal row of carpals
forms carpal tunnel
capitate is the key
what is the distal transverse arch
MCP joints
sides of arch are mobile
MCP of 2nd/3rd is key
what is the longitudinal arch
follows shape of 2nd/3rd rays
proximal end is rigid
distal end is mobile
MCP at 2nd/3rd is key
where is the central pillar
2nd/3rd CMC rigidly joined
what is the CMC joints
distal row carpals and bases of MC bones
match the carpal with the MC
2- trapezoid/capitate/trapezium
3-capitate
4-hamate/capitate
5-hamate
describe the kinematics of the 2nd/3rd
very little motion
central pillar
firm attachments
describe the kinematics of 4th
FLX/EXT at 20 deg
IR- 27 deg
describe the kinematics of 5th
FLX/EXT- 28 deg
IR- 22 deg
describe the kinematics of 4/5th
convex base to concave hamate
mobility for cupping- FLX and IR
they are linked- 44 deg FLX/EXT
what is the kinematics of the thumb
saddle joint
2 DOF- FLX/EXT(frontal) and ABD/ADD(sagittal)
what is the arthro of the thumb in ABD/ADD
ABD- palmar roll dorsal slide
ADD- dorsal roll palmar slide
what is the arthro of the thumb in FLX/EXT
FLX- medial roll/slide
EXT- lateral roll/slide
describe the thumb kinematics of ABD/ADD
convex MC on concave trapezium
elongates ADD pollicis and most ligs
describe the thumb kinematics of FLX/EXT
concave MC on convex trapezium
what is the combo of thumb opposition
thumb MC ABD
FLX and medial RT toward pinky
closed pack position
what is the key for mechanical stability critical for stability of the hand
MCP jts
what is collateral lig of the fingers
attach at tubercle
cord is thick and strong
what is volar plate
dense, thick fibrocartilage
base of prox phalanx thinner elastic portion
what is fibrous digital sheath
form tunnels or pulleys for extrinsic finger flexors anchored to plates
what is the osteo of MCP joints
FLX/EXT- sagittal 90-115, ext past neutral 20-45
ABD/ADD- frontal 20 deg from midline
what is the arthro of MCP
concave phalanx on convex MC head
roll and slide same way
what is the arthro/osteo of the MCP thumb
convex head and concave prox phalanx
1 DOF- FLX/EXT
ABD/ADD is accessory motion
what limits hyperextension in IP joints
volar plates
what are check rein lig
reinforce palamar plates and assist in limiting hyperextension
what are the kinematics of of the IP joints
concave base rolls and slides palmar direction
which IP joint has hyperextension
DIP- 30 deg
what helps provide tension and helps stabilize in IP joints
dorsal capsule
what m group does the radial n innervate in the hand
extensive extensor
ED, EDM, EI, EPL, EPB, ABD PL
what m group does the median n innervate in the hand
extrinsic flexors
FDS, FDP, FPL, ABD PB, OP, FPB, thenar eminience, lat 2 lumbricals
what m group does the ulnar n innervate in the hand
hypothenar m
medial half of FDP, FDM, ABD DM, PB, ADD P, all interossei, and 2 medial lumbricals
what does the digital synovial sheath serve as
nutritional and lubrication
what has a greater force at PIP as a proximal stabilizer
greater force stabilizer at ED
where do the extrinsic extensors of fingers cross
at the wrist under retinaculum
what attaches to the hood and assists ED with EXT at IP joints
lumbricals and interossei
where does the extrinsic m of the thumb comprise at
snuff box
what are the intrinsic m of the hand
thenar
hypothenar
ADD pollicis
lumbricals/interossei
describe the thenar eminence
ABD PB, FPB, OP
attach to transverse carpal lig
grasp and opposition, CMC ABD, FLX, IR
describe the hypothenar eminence
FDM, ABD DM, ODM, PB
ABD DM FCU contracts to stabilize
cupping- transverse arch
what m in the hand has high level m spindles
lumbricals and interossei
what force couple happens when trying to extend the thumb
FCU activates with thumb EXT (EPL and ABD PL)
what force couple happens when flexing your IP joints
ED activates to resist wrist flexion when flexing IP jts (FDS/FDP)