EXAM2_G14_EXTENSOR_UE Flashcards
What is the grove on the diaphysis of the humerus? what travels along that groove?
Radial or Spiral Groove
-radial nerve
What is feature proximal to the lateral epicondyle?
Supra epicondylar ridge
What is the bony feature on the lateral inferior surface of the trochlear notch?
Supinator Crest
What is the tubercle on the posterior side of the distal end of the radius called?
Lister’s tubercle
What part of the ulna dives into the fossa of the humerus?
What is inferior process called?
What feature called where radius articulates with ulna?
Olecranon process
Coronoid process
Radial notch of ulna
TRICEPS
OINA
Long- infraglenoid tubercle
Lateral- Posterior humerus above spiral groove
Medial- Posterior humerus below spiral groove
Inserts on OLECRANON
EXTENDS FOREARM
RADIAL C6,7,8
What neurovascular structures course through the spiral groove? between what two muscles?
Between Lateral and medial head of triceps brachii
What part of triceps participates in extension of the shoulder?
Long head
ANCONEUS
OINA
o- lateral epicondyle
I- olecranon, proximal ulna
WEAK extensor of elbow- stabilizes elbow
RADIAL (7,8,t1)
What reflex tested by tapping on back of elbow (distal humerus) proximal to elbow..
What spinal cord segments tested by this reflex?
Triceps reflex tests C7 spinal cord segment
characteristics of superficial group of extensor forearm muscles
- attach at lateral epicondyle
Cross elbow joint
innervation is radial nerve or deep branch of radial nerve
Deep group muscle characteristics
- dont cross elbow joint (except 1)
- Innervates deep branch of radial nerve and posterior interosseous nerve
BRACHIORADIALIS
What compartment does it belong to?
lateral supracondylar ridge to distal radius
Flexes elbow
Radial nerve
C5,6,7)
IT IS PART OF THE POSTERIOR COMPARTMENT
Brachioradialis is a landmark for what neurovasculature?
Radial artery and superficial radial nerve
Brachioradialis tendon reflex tests what spinal cord segment?
C6 Spinal cord segment
Extensor carpi radialus longus
lateral supracondylar ridge to base of 2nd metacarpal
Extends abducts wrist
Radial (C6,C7)
Extensor carpi radialis brevis
lateral epicondyle to base of 3rd metacarpal
Extends abducts wrist
deep branch radial (c7, 8)
Extensor digitorum
Lateral epicondyle to extensor expansions of digits 2-5
Extend wrist, extends digits 2,3,4,5
Deep branch radial (c7,c8)
Extensor digiti minimi
Lateral epicondyle to extensor expansion of digit 5
extends pinky
deep branch of radial C7,c8)
What limits the independent movement of fingers from a flexed position?
Intertendinous connections
What tendon sheath for extensors? which one has its own?
common synovial sheath
extensor digiti minimi travels with extensor digitorum but its tendon enters the hand in a separate tendon sheath
Extensor carpi ulnaris
Lateral epicondyle to base of 5th metacarpal
extension adduction of wrist
deep branch radial c7,c8
What is tennis elbow called?
Lateral epicondylitis
Tinitis- or inflammation of common extensor tendon and periosteum of the lateral epicondyle
What are the 6 muscles of the superficial group?
ECU,EDM,ED,ECR longus, ECR brevis, Brachioradialis
What are the 6 muscles of the deep posterior forearm?
Supinator, Aconeus, AbPL, EPB, EPL,
What is the supinator a landmark for?
This is where the deep branch of radial nerve becomes the Posterior Interosseous nerve
Supinator OINA
Lateral epicondyle, supinator crest (proximal ulna)
to proximal radius
Supinates forearm
Deep branch radial c7,c8
Landmark for posterior interosseous nerve
Abductor pollicis longus
proximal ulna, radius, and interosseous membrane to base of metacarpal 1
extends thumb (mainly CMC joint ) abduction of thumb
Posterior interosseous nerve c7,c8
Extensor Pollicis Brevis
Distal 1/3 of radius, interosseous membrane to proximal phalanx base of thumb
Extends thumb at MCP
Posterior interosseous nerve C7,c8
Extensor pollicis Longus
middle 1/3 of ulna and interosseous membrane to distal phalanx of thumb at IP joint
Extension of thumb at IP joint
Posterior interosseous (c7c8)
In order to extend the thumb at the IP joint:
What muscle?
Tendon travels around what bony feature? why?
Extensor pollicis longus passes medial to LISTERS tubercle which changes direction of pull for the EPL from the forearm to the thumb
Where is Listers tubercle? What muscle uses it as a tension point?
Posterior end of radius on dorsal side
used by Extensor Pollicis longus
Extensor Indicis
Distal 1/3 of ulna and interosseous membrane to extensor expansion of Digit 2
Extends index finger
Posterior interosseous nerve c7,c8.
Snuff box muscles
what inside? 3 things
What can you palpate inside the snuff box?
AbPL, EPB, EPL
Radial Artery
Scaphoid and trapezium
Superficial branch of radial n.
Can palpate SCAPHOID
What is risk of break in scaphoid?
Poor blood supply to proximal fragment and can cause avascular necrosis resulting in chronic wrist pain and arthritis
What are the muscles in the dorsum of the hand?
NONE
Septa creates six osseofibrous tunnels (compartments)
1 starts at thumb side 6 ends at pinky side
Compartment 1: AbPL, EPB, Compartment 2: ECRL, ECRB Compartment 3: EPL (goes around tubercle) Compartment 4: ED, Ei Compartment 5: EDM Compartment 6: ECU
Stenosing tenosynovitis of the synovial sheath of tendonds in the 1st compartment
de Quervian’s disease
F>m (6:1)
>40yo
repetitive use causes friction of tendons results in degeneration and thickening of tendon
Pain over lateral wrist radiating into forearm and thumb
What is de Quervians disease?
What are symptoms?
What test used?
Stenosing Tenosynovitis of synovial sheath of tendons in 1st compartment (AbPL, EPB)
pain over lateral wrist, radiating into forearm and thumb
Finkelstein’s test pathognomonic (diagnostic)- reproduce symptoms
patient grasps thumb and abducts quickly -creates TERRIBLE pain
What accounts for 50-70% of all hand masses?
Ganglion cyct (synovial cyst) benign, mucin filled cyst, found in relation to a joint, ligament, or tendon.
most common arise dorsally from scapholunate ligament
NOT A TRUE CYST not filled w/ synovial fluid or lined by ET.
F>M 20-30yo
Lumbercals and interossei muscles
FLEX at MCP
EXTEND at PIP and DIP
bc of extensor expansion
EXTENSOR EXPANSION Lateral band
Insertion of long extensor tendon to base of distal phalanx
EXTENSOR EXPANSION Central band
Insertion of long extensor tendon to base of middle phalanx
Extensor tendon injury
unable to extend distal phalanx
Mallet finger
flexion deformity of the DIP joint
Most common- closed tendon injury of athletes, in ring , little fingers
Reptures tendon or avulsion fracture at distal phalanx
Results in inability to actively extend distal phalanx (passive extension unaffected)
Chronic untreated Mallet finger turns into what deformity?
Swan-neck deformity- hyperextension of PIP joints
Lateral bands displace proximal/dorsally resulting in decreased extension forces on the PIP joint
Boutonniere deformity
: injury to central band by forced flexion of PIP joint
2nd most common closed tendon injury in athletes
-FDS flexes pip joint and lateral bands become displaced and act as flexors instead of extensors
DIP joint extended while PIP joint flexed
LANDMARKS of RADIAL NERVE
radial “spiral groove” of humerus
- Radial nerve travels with profunda brachii via spiral groove
- branches in arm:
- triceps, anconeus, brachioradialis, ECRL
-cutaneous branches to posterior arm and forearm:
Posterior brachial cutaneous
inferior lateral cutaneous
posterior antebrachial cutaneous n
Where does radial nerve enter into the arm?
Right under the teres minor and travels between lateral and medial heads of triceps through the radial groove
What 3 cutaneous nerves of radial artery and where is sensation?
- proximal medial dorsal of ARM (post. brachial cut nerve)
- Proximal lateral dorsal of ARM (inferior lateral cut n)
- elbow and central portion of dorsal aspect of forearm and back of hand of thumb and index finger (posterior antebrachial cutaneous nerve)
Where does radial nerve branch?
Cubital fossa- MOTOR
- deep branch passes through slit in the supinator called Arcade of Frohse
and superficial branch- SENSORY
lays deep to brachioradialis w/ radial artery
IF radial nerve or branches entrapped what two conditions?
Radial tunnel syndrome
Posterior interosseous nerve palsy
Cheiralgia paresthetica
compressed superficial branch of radial n at wrist producting pain and paresthesias in the distribution of the nerve
could be caused by handcuffs, tight bracelets, watches.
CUTANEOUS on dorsum of hand for Radial, Median, Ulnar
Radial: skin on back of hand of 1,2,3 (not fingertips)
Median- back hand fingertips 1,2,3,
Ulnar- back hand skin of digits 4,5
Radial artery branches in dorsum of hand
- Dorsal carpal arch
Dorsal metacarpal artery of THUMB
Ulnar artery forms dorsal carpal branch and feeds digital branches
