ELBOW Flashcards
3 synovial joints within the synovial joint capsule
humeroulnar
humeralradial
proximal radioulnar
the elbow responds ____ to trauma and improper ____ and injury to on part does what?
- poorly
- treatment
- affects the other parts as well
the medial condyles and epicondyles are common origin of?
the lateral condyles and epicondyles are common origin of?
- flexor tendon
- extensor tendon
3 fossae of the elbow joint
coronoid, radial and olecranon
osteokinematics of the radius and ulna on the humerus
swing
flexion of the humeroulnar joint is limited by (2)
- and it requires sufficient length of ? (4)
- coronoid process abutting coronoid fossa OR by soft tissue approx
1. posterior capsule
2. posterior fibers of UCL
3. ulnar nerve
4. elbow extensors
extension of humeroulnar joint is limited by?
- and it requires sufficient length of? (3)
- olecranon process abutting olecranon fossa
1. anterior capsule
2. anterior fibers of UCL
3. elbow flexors
what is the cubital angle a measure of?
ad what is it on average?
why does this happen?
carrying angle
- when in anatomical potion the forearm deviates laterally in relation to the humerus
- -> 15 degrees
- -> greater in females
- b/c the medial trochlea extends more distally
the head of the radius spins under what ligament?
ring around the head of the radius
annular
does the middle radioulnar joint limit pronation and supination?
NO
with what movements is the biceps brachii active and with what movements is it not?
- little to no activity of biceps brachii in slow elbow flexion with forearm pronated, but active with a load
- always active in flexion with supination with or w/o a load
what is the more active muscle for supination
biceps brachii> supinator
with the elbow at 90 degrees the biceps are about ___ times more effective than supinator.
and with elbow fully extended?
- 4 times
- 2 times
when is it possible to have only supinator active and not biceps
fully extended, slow supination without resistance
is the supinator effectiveness affected by the elbow angle
no
why cant muscles be classified classified as synergists or antagonists
because they can only b labeled like that for specific movements, changes depending on movement requirements
can you still simultaneously flex the elbow and supinate the forearm if the musculocutaneous nerve is paralyzed
yes still have supinator and brachioradialis that have different nerve supply
what makes the boarders of the anatomical snuff box?
- Anterior (closest to palm): abductor pollicis longus & extensor pollicis brevis
- Posterior: extensor pollicis longus
- Proximal- radial styloid process
- Floor- scaphoid; trapezium, and base of 1st MC
most commonly fractured and most frequently dislocated carpal bone
- scaphoid
- lunate
what gets compressed with ulnar deviation
TFCC
what does the TFCC have?
a mensiscus!
mid carpel joints accounts for HOW much of radial and ulnar deviation
- half the radial deviation
- 1/3 of the ulnar deviation
wrist flexion is more at the what joint?
and wrist extension more motion occurs at
- radiocarpal joint
- midcarpel joint
maximum wrist extension occurs with fingers ___
maximum wrist flexion occurs with fingers___
- flexed
- open (extended)
the palmar carpal ligament maintains the ?
transverse carpal arch
the palmar carpal ligament makes the roof of the carpal tunnel and covers the?
- median nerve, tendons of flexor pollics longus, flexor digitorum superficialis, and flexor digitorm profundus in synovial sheaths
2 functions of extensor reticulum
- ‘bowstringing’ of the extensor tendons with wrist extension
- synovial tendon reducing friction b/w the tendons and ones and retinaculum
the extensor reticulum is continuous with?
the palmar carpal ligament
what is the most variable muscle in the body
palmaris longus
what muscle is absent in ~ 8% of ppl and additional 4 % are missing?
palmaris longus
- left or right
extensors are generally innervated by what nerve?
and flexors? except?
- extensors: radial nerve
- flexor: medial nerve
except the flexor carpi radialus longus is radial nerve
what joints are important movements for hand function in relation to transverse arch of the hand from a closed fist to the open hand
carpometacarpal 2-5
the 1st carpometacarpal joint is a common site for?
OA (arthritis)
what ligaments attach to the head of of the metacarpals and the bases of the phalanges?
meidal and lateral collateral ligaments
the digital tendons fo the extensor muscles and the many intrinsic muscles terminate in the ?
- extensor expansion hood
what muscles make up the outcropper muscles and whose tendons make the anatomical snuff box
abductor pollicis longus
extensor pollicis longus
extensor pollicis brevis
how many fingers do you test a time for flexor digitorum superficialis and profundus
one
when grasping what muscles contract?
contraction of what is proportional to the strength of grasp?
- wrist flexors and extensors
- wrist extensors
when you extend your fingers, what do your flexors do?
stabilize the wrist from extending
what are the most palmar intrinsic muscles of the hand
four lumbricals
what is the bunnel littler test
lumbrical vs PIP joint tightness
how do you stretch your lumbricals?
extend your MCP and flex your IP joints
what are the 4 muscles of the thenar group and their innervation
- Adductor Pollicis (Ulnar n) 2.Abductor Pollicis Brevis (Median n)
- Opponens Pollicis (Median and Ulnar n)
- Flexor Pollicis Brevis (Median and Ulnar n)
what muscles make up the hypothenar group
Abductor Digiti Minimi Flexor Digiti Minimi Opponens Digit Minim
is the first metacarpal bone of thumb bound to other metacarpals by ligaments?
no
how many muscles move the thumb
9
name the 4 extrinsic muscles of the thumb and 5 intrinsic
Intrinsic (thenar):
Abductor Pollicis Brevis Adductor Pollicis
First Dorsal Interosseous Flexor Pollicis Brevis Opponens Pollicis
Extrinsic:
Abductor Pollicis Longus Extensor Pollicis Brevis Extensor Pollicis Longus Flexor Pollicis Longus
Radial Nerve innervates what muscles? (13)
triceps, anconeus, brachioradialis, brachilais, supinator, extensor carpi radialis
longus and brevis, extensor carpi ulnaris, extensor digitorum, extensor pollicis longus and brevis, extensor digit mimimi, extensor indices, abductor pollicis longus
Ulnar nerve innervates what muscles? (11)
flexor carpi ulnaris, medial 2 lumbricals and Flexor digitorum profundus, hypothenar muscles (flexor digiti mimi, opponens digiti minimi, abductor digiti minimi), flexor pollicis brevis, palmar and dorsal interossei, adductor pollicis, opponens pollicis,
Median nerve innervates (10)
- Pronators,
- flexor carpi radialis
- flexor digitorum superficialis,
- flexor digitorum profundus (lateral 2)
- lateral 2 lumbricals,
- thenar muscles (flexor pollicis longus, flexor pollicis brevis, abductor pollicis brevis, opponens pollicis)
