Elbow Flashcards
function of elbow in CKC
stability and power
function of elbow in OKC
hand position and function
major landmarks of the humerus
condyles, epicondyle, trochlear, capitulum, capitotrochlear groove and trochlear groove, coronoid fossa, radial fossa, olecranon fossa
important landmarks of the ulna
olecranon, ulnar groove, trochlear (semilunar notch), trochlear (longitudinal ridge), ulnar tuberosity, radial notch
important landmarks of the radius
radial head (fovea), radial neck, radial tuberosity, interosseous border
what kind of joint in the trochlear (humeroulnar)
what it is shape
modified uniaxial hinge joint
oblique with trochlea (medial) more distal than capitulum (lateral)
rotation of distal humerus related to shaft and rotation o f proximal ulan related to shaft
what is the function of these rotations
humerus = rotated anteriorly ulna = rotated posteriorly
function: increase ROM (145)
more flexion in supination or pronation
supination
resting position of the radiohumeral joint and closed position of the trochlear joint
full extension and supination
open position of the trochlear joint
70 degree flexion and 10 degree supination
closed position of the radiohumeral joint
90 flexion, 5 supination
resting position of superior radioulnar
35 supination and 70 flexion
closed position of super radioulnar
full supination or full pronation
what is the cubital angle
result of oblique axis through trochlea and capitulum
combo of GH external rotation, elbow extension and supination
“carrying angle”
larger in females than males
what is cubital varus
carrying angle abnormality
result of distal humeral fracture
causes straight line at elbow or hand pointing medially instead of laterally
ROM of supination and pronation
90 degrees each
how many bursa at elbow
name 3 associated with triceps
what is the main force absorption bursa
7 bursa
Triceps: intratendinous, subtendinous, subcutaneous
Olecranon bursa
ligaments at the elbow
medial collateral - anterior, posterior and transverse
lateral collateral
stability at proximal radioulnar joint provided by
annular ligament
lateral collateral
oblique cord
quadrate
stability at distal radioulnar joint provided by
articular disc (TFCC) Doral and palmar radioulnar ligaments interosseous ligaments
what ligaments blend with the capsule
annular
ulnar (medial) collateral ligament
what does the medial collateral ligament stabilize against
valgus force
what is the cubital tunnel made by
the MCL
function of radial collateral ligaments
stabilize against varus forces
stabilize against humeroradial subluxation
assist annular ligaments
what is the function and location of the quadrate ligaments
inferior to ulnar notch and attaches to radial neck
resist excessive supination (more than resting pronation)
limits spin of the joint, contributes to radioulnar stability
what is the oblique cord
facial band running lateral from below radial notch on teh ulna to below radial tuberosity of the radius
runs in opposition to the fibres of the Interosseous membrane
when is the oblique cords tight
in supination
function of teh interosseous membrane
reinforce proximal and distal joints
does not limit supination or pronation
shock absorber
muscle attachment site
dorsal and palmer radioulnar ligaments
- continuous with?
- support what
continuous with TFCC and joint capsule
support radius against ulna
motion where biceps and triceps are synergists
turning the doorknob (twisting)
strength peak position of elbow
90-120 degree flexion
flexors of the elbow and nerve innervation
brachialis - muscularcutaneous
biceps - musculocutaneous
brachioradialis - radial
pronator teres - median
recruitment order of the triceps
single before two joint, smaller before larger
medial, lateral long
long head = strongest and largest
peak force position of triceps
70-90 degrees flexion
function of triceps of CKC
UE stabilizer
function of anconeous
tightens loose posterior capsule during extension
elbow extensors and innervation
triceps
anconeous
radial nerve
when is supinator able to supinate
motion is slow, resistance is light or elbow is extended
does position effects ability of supinator to supinate
no
which pronator probates regardless of arm position
pronator Quadratus
pronators/supinators and innervation
supinator - radial
biceps - musculocutaneous
pronator teres - medial
pronator Quadratus - median
which is recruited first for elbow flexion
brachialis before biceps brachii
active insufficient for biceps
full shoulder and bled flexion and supinator
active insufficiency for triceps
full shoulders and elbow extension
what muscles can extend the elbow in CKC
pectoralis major
what muscles are involved in pull ups and how
biceps and brachialis flex elbow concentrically and contrail extension eccentrically
supinator and biceps supinate