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138 Cards in this Set

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What type of joint is SC joint?

saddle synovial with intra-articular disc

Saddle Synovial with INTRA-ARTICULAR DISC

When does SC joint move?


When is SC joint injured?

ED


-moves into Elevation and Depression during shoulder ELEVATION/DEPRESSION;


-injured AFTER the AC joint and CLAVICLE


*Think of this in alphabetical order AC joint, clavicle, then SC joint are injured

What type of joint is the AC joint?

plane synovial

Plane Synovial

What ligaments are associated with the AC joint

coracoclavicular ligament


Acromioclavicular ligament

1) Coracoclavicular ligament (Trapezoid [L] and Conoid [M])



2) Acromioclavicular ligament

What is the function of the coracoclavicular ligament

1) trapezoid (lateral) and conoid (medial) portions: STABILIZE AC joint and PREVENT UPWARD DISPLACEMENT of HH


2) PREVENT SEPARATION  of scapula from clavicle

1) Trapezoid (lateral) and Conoid (medial) portions: STABILIZE AC joint and PREVENT UPWARD DISPLACEMENT of HH



2) PREVENT SEPARATION of scapula from clavicle

Where is the coracoclavicular ligament positioned relative to other structures?

over supraspinatus


can be involved in impingement syndrome

Covers the Supraspinatus


can be involved in impingement syndrome

When is the AC joint injured?

during SHOULDER SEPARATION which leads to injury to ligaments of AC joint and unstable AC joint causing pain and dysfuncition of shoulder joint

during SHOULDER SEPARATION which leads to injury to ligaments of AC joint and unstable AC joint causing pain and dysfuncition of shoulder joint

What type of joint is the glenohumeral joint?

multi-axial ball and socket (HH and glenoid cavity of scapula

What stabilizes the GH joint?

mobility > stability but


stabilized by anterior and posterior joint capsule, glenoid labrum, and long head of biceps mm (continuous with the labrum)

mobility > stability but stabilized by A and P JOINT CAPSULE, glenoid LABRUM, and long head of BICEPS mm (continuous with the labrum)

What is the glenoid labrum

fibrocartilaginous rim that deepens glenoid cavity and stabilizes GH joint
-long head of biceps mm is continuous with labrum

FIBRO-CARTILAGINOUS rim that deepens glenoid cavity and stabilizes GH joint


-long head of biceps mm is continuous with labrum

What is the ligamentous support of the GH joint?

Superior, inferior, and middle GH ligaments = static restraint to excessive anterior translation

SIM


SUPERIOR, INFERIOR, AND MIDDLE GH ligaments = static restraint to excessive anterior translation

What are the rotator cuff muscles?

teres minor, infraspinatus, supraspinatus, subscapularis

SITS


Supraspinatus,


Infraspinatus,


Teres MINOR, Subscapularis

What provides tendon support to GH joint?

Rotator cuff mms that insert INTO joint capsule


dynamic support provided by muscles contracting and pulling head of humerus down into lower and wider portion of glenoid cavity and allowing full overhead elevation of arm

Rotator cuff mms that insert INTO joint capsule


-dynamic support provided by muscles contracting and pulling head of humerus down into lower and wider portion of glenoid cavity and allowing full overhead elevation of arm

What happens when static support of GH joint is compromised?

asynchronous firing of the rotator cuff mm may cause subacromial impingement

ASYNCHRONOUS firing of the rotator cuff mm may cause subacromial IMPINGEMENT

What joints are involved to raise arm overhead?

4 joints: GASS


GH joint


AC joint


SC joint


Scapulothoracic articulation

How many degrees of elevation occur at GH joint? How many at Scapulothoracic articulation?

120 deg at GH


60 deg at Scapthoracic

120 deg at GH


60 deg at Scapthoracic


GS - 2:1

What motion of clavicle occur during arm elevation?

ERB Elevates: Elevates, Retracts, Backward rotation


-during first 90 deg shoulder abd, clavicle elevates 35-45 deg at SC joint


-full scapular UR requires 45-50 deg clavicle posterior/backward rotation (at SC joint)

What is the scapulohumeral rhythm?

ratio of scapular to humeral motion for elevation is 1:2

ratio of scapular to humeral motion for elevation is 1:2 (or humeral to scapular ratio 2:1)

Describe the muscular stabilizers of the shoulder

RC work as group to hold HH in glenoid cavity esp during ABD


-supraspinatus and coracoacromial arch guard shoulder superiorly


-subscapularis stabilizes anteriorly


-infraspinatus and teres minor stabilize posteriorly

RC work as group to hold HH in glenoid cavity esp during ABD


-supraspinatus and coracoacromial arch guard shoulder superiorly


-subscapularis stabilizes anteriorly


-infraspinatus and teres minor stabilize posteriorly

Muscles for UR of scapula during elevation

Serratus anterior and (trapezius) lower trapezius

URSUL (like URSULA)


SERRATUS ANTERIOR and (trapezius) UPPER and LOWER trapezius

muscles for downward rot (esp with purposeful shoulder extension i.e. wood chopping)

rhomboids, levator scapula, pec minor

DRRLP


Rhomboids, Levator scapula, Pec minor

what muscles contribute to protraction?

pec minor and SA

PPS


PS: Pec minor and SA

what mm contribute to retraction?

RT: Rhomboids and middle & lower Traps

ReTraction-RT


RT: Rhomboids and middle & lower Traps

what mm contribute to scapular elevation?

Upper traps and levator scapula

UL


Upper traps and Levator scapula

what mm contribute to scapular depression?

pec minor and lats

pec minor and lats

what bursa is at shoulder?

subacromial bursa which is fused with subdeltoid bursa


-palpable by extending humerus


-located over bicipital groove under the deltoid mm


-separates deltoid from RC


-injury=bursitis & shoulder tenderness and restriction of movement

SUBACROMIAL bursa which is fused with subdeltoid bursa


-palpable by extending humerus


-located over bicipital groove under the deltoid mm


-separates deltoid from RC


-injury=bursitis & shoulder tenderness and restriction of movement

Describe circulation into the axilla

axillary artery is palpable in lateral wall of inferior part of axilla


-injury occurs when inferior part pressed against humerus (e.g. resting on crutches)

AXILLARY ARTERY is palpable in lateral wall of inferior part of axilla


-injury occurs when inferior part pressed against humerus (e.g. resting on crutches)

what is crutch palsy?

compression of radial nn in axilla due to resting on crutches (also can press the axillary aa against humerus)

compression of RADIAL nn in axilla due to resting on crutches (also can press the axillary aa against humerus) = WRIST DROP

Draw Brachial Plexus

what nerves branch off before trunks form? i.e. off rami

dorsal scapular


long thoracic nn


 

dorsal scapular


long thoracic nn


what does dorsal scapular nn innervate and results of injury to the nerve?

levator scapula and rhomboids


injury effects scapular retraction and downward rotation

LEVATOR SCAPULA and RHOMBOIDS


-injury effects scapular retraction and downward rotation

when do the TRUNKS form?

superior, middle, and inf


as they pass over the first rib


C8 and T1 pass on either side of the first rib

superior, middle, and inf


-as they pass over the first rib


C8 and T1 pass on either side of the first rib

where does the suprascapular nn arise and travel to?

from superior trunk and passes beneath trapezius through scapular notch to innervate the supraspinatus and infraspinatus

from superior trunk and passes beneath trapezius through scapular notch to innervate the supraspinatus and infraspinatus

what does injury to the suprascapular nerve cause and when does it happen?

injury to nerve from impingement by the superior transverse scapular ligament causes pain and decreased abd and ER of the shoulder

injury to nerve from IMPINGEMENT by the SUPERIOR TRANSVERSE SCAPULAR LIGAMENT causes pain and DECREASED AB and ER of the shoulder

where do trunks DIVIDE?

into divisions (3 ant and 3 post) beneath the clavicle

into divisions (3 ant and 3 post) BENEATH THE CLAVICLE

where are lateral, posterior and medial CORDS formed?

beneath pec min

BENEATH PEC MINOR

what is the MOI for cord injuries?

postural dysfunction or traumatic injury due to impingement of the brachial plexus beneath the clavicle or pectoralis minor

when do the brachial plexus BRANCHES form?

as the cords pass under the pectoralis minor

what is the most frequent fracture site of the proximal humerus?

surgical neck (where bone narrows to become the shaft)

surgical neck (where bone narrows to become the shaft)

what brachial branches are injured with fractures of humerus

axillary, radial, ulnar

URA


ulnar


radial,


axillary


*Ura fractured his humerus

what type of joint is the ulnohumeral joint

uniaxial hinge between ulnar trochlear notch and the trochlea of the humerus (anterior/inferior)

uniaxial HINGE between ulnar trochlear notch and the trochlea of the humerus (anterior/inferior)

what ligament is at the ulnohumeral joint?

ulnar collateral ligament stabilizes joint and has carrying angle of 10-15 deg in men and 20-25 deg in women with arm at the side

ULNAR COLLATERAL (AKA: LCL) ligament stabilizes joint


-carrying angle:


-10-15 deg in men


-20-25 deg in women with arm at the side

What happens with movement at the ulnohumeral joint?

gaps medially in full extension, laterally in full flexion and glides side to side in supination/pronation


*Look at your arm extended and picture the joint to help with this

what type of joint is the radiohumeral joint?

uniaxial hinge between radial head and the capitulum of the humerus

What ligament is associated with the radiohumeral joint?

radial collateral ligament: provides lateral stablity


injury may interfere with elbow flexion and extension

RADIAL COLLATERAL ligament: provides lateral stablity


injury may interfere with elbow flexion and extension

what type of joint is the superior radioulnar joint?

uniaxial pivot joint between the radial proximal head and the medial portion of the proximal ulna

uniaxial pivot joint between the radial proximal head and the medial portion of the proximal ulna

what motion occurs at superior radioulnar joint?

spherical radial head allows ROTATION needed for supination/pronation

what ligament is at the superior radioulnar joint?

annular ligament provides stability by surrounding the radial head

ANNULAR ligament provides stability by surrounding the radial head

what can injury of the superior radioulnar joint cause?

limitation in ability to control the position of the hand

What makes up the middle radioulnar joint?

interosseous membrane and the oblique cord


-interosseous membrane stabilizes the elbow during pushing movements


-oblique cord resists distal displacement of the radius during pulling movements

interosseous membrane and the oblique cord


-interosseous membrane stabilizes the elbow during pushing movements


-oblique cord resists distal displacement of the radius during pulling movements

How many joints make up the elbow?

3 joints:


1. ulnohumeral joint


2. radiohumeral joint


3. radioulnar joints


How many groups of muscles control movements at the elbow?


How many total muscles?

-4 groups that synergistically control elbow flexion/ext and supination/pronation


-8 muscles exert force to move the elbow

What muscles contribute to elbow flexion?

brachialis, biceps brachii, & brachioradialis


 


(flexor carpi ulnaris and pronator teres may contribute)

B3: brachialis, biceps brachii, & brachioradialis



(flexor carpi ulnaris and pronator teres may contribute)

What is the main elbow flexor?

brachialis

**BRACHIALIS**


(NOT biceps brachii)

In what elbow/forearm positions does the brachialis flex the elbow?

acts in shoulder flexion or extension & forearm supination or pronation

acts in shoulder flexion or extension & forearm supination or pronation

In what elbow/forearm positions does the biceps brachii act on the elbow?

when in supination, flexes the forearm


or


flexes the forearm when lifting >2 lb

What movement does brachioradialis cause?

flexes the elbow


and


STABILIZES supination and pronation during strong resistance

flexes the elbow


and


STABILIZES supination and pronation during strong resistance

Besides the main elbow flexors, what other muscles may contribute to elbow flexion?

flexor carpi ulnaris


pronator teres 

Flexor carpi ulnaris


Pronator teres

What are the main elbow extension muscles?

triceps brachii is the main extensor


with ANCONEUS assisting and providing STABILITY during supination and pronation

TRICEPS brachii is the main extensor


with ANCONEUS assisting and providing STABILITY during supination and pronation

Besides triceps and anconeus, what other muscles may contribute to elbow extension?

PEC MAJOR and ANT DELT facilitate elbow extension in closed chain movements such as push-ups or pushing heavy objects


(Think of doing push ups)

What muscles produce supination?

supinator and biceps brachii

supinator and biceps brachii

when does the supinator act?

with low loads and with slow movements

with LOW loads and with SLOW movements

when does the biceps brachii cause supination?

when elbow is flexed to 90 deg

when elbow is flexed to 90 deg

what muscles produce pronation?

pronator teres, pronator quadratus, and FLEXOR CARPI RADIALIS

when is the pronator quadratus active for pronation?

during low loads


(similar to the supinator)

Describe coordination between muscle antagonist during the action of pulling objects

elbow flexion by biceps brachii


triceps aids shoulder extension and controls elbow flexion

Describe coordination between muscle antagonist during the action of pushing an object away from body

triceps extends elbow


biceps controls extension and helps with shoulder flexion

Describe coordination between muscle antagonist during the action of turning door knobs or screwdrivers clockwise

biceps supinates


TRICEPS counters flexion action

Describe coordination between muscle antagonist during the action of using a fork

biceps supinates and flexes elbow to bring fork to mouth


biceps contracts eccentrically to control putting down fork

what bursae are at the elbow

subcutaneous and subtendinous bursae


 

SUBCUTANEOUS and SUBTENDINOUS bursae


where is the subcutaneous olecranon bursa and how is it injured?

located in tissue over the olecranon


injury due to repeated excessive friction (="student's elbow")

located in tissue over the olecranon


injury due to repeated excessive friction (="student's elbow")

Where is the subtendinous olecranon bursa located? and when/how is it injured?

between triceps tendon and the olecranon


injury: less common and occurs with excessive friction between triceps tendon and olecranon (e.g. during certain assembly jobs)

What artery is associated with the elbow region and where can it be palpated?

brachial artery which is a continuation of the axillary artery


palpated over anterior region of cubital fossa

BRACHIAL artery which is a continuation of the axillary artery


palpated over anterior region of cubital fossa

where is compression of the brachial artery the most effected?

middle of the humerus

middle of the humerus

what injury occurs with occlusion or laceration of the brachial artery

ischemia of the flexor muscles of the forearm causing a Volkmann's ischemic contracture of the involved muscles

ischemia of the flexor muscles of the forearm causing a Volkmann's ischemic contracture of the involved muscles

what is Volkmann's ischemic contracture?

occurs when there is ISCHEMIA TO FOREARM FLEXORS resulting in contractures of elbow flexion, forearm pronation, wrist flexion, MCP extension, and IP flexion, and thumb adduction

where is the head of the ulna and the head of the radius?

head of radius= at the elbow


head of ulna = at wrist

Where are the styloid processes of the ulna and radius?

ulna = distal end on the medial side


radial styloid process = distal end on lateral side of the bone


-radial styloid process is more distal than ulnar styloid process

where is the radius most likely to be fractured?

distal radial fracture = Colles' fracture


MOI = FOOSH

distal radial fracture = Colles' fracture


MOI = FOOSH

what is a Colles' fracture

distal radial fracture with MOI commonly fall on outstretched hand


(If I had a collie, I would name him Radius)

Describe bony anatomy of ulna.

-Trochlear notch, coronoid process, olecranon process


-Humerus has Trochlea, coronoid fossa, olecranon fossa

-Trochlear notch, coronoid process, olecranon process


-Humerus has Trochlea, coronoid fossa, olecranon fossa

where can you palpate the head of the radius?

with elbow extended, just distal to lateral epicondyle of humerus

where can the radial styloid process be palpated?

on lateral aspect of wrist

where is the ulnar nerve located at the elbow?

posterior to the medial epicondyle

posterior to the medial epicondyle

when/where is ulnar nerve most likely to be compressed?

in Osborn's fasica, forming the cubital tunnel, posterior to medial epicondyle 

in Osborn's fasica, forming the cubital tunnel, posterior to medial epicondyle

Name the carpal bones

Some lovers try positions that they can't handle (lateral to medial on volar surface)


 


proximal row: (lat to med) Scaphoid, lunate, triquetrium, pisiform,


distal row: trapezium, trapezoid, capitate, hamate

Some lovers try positions that they can't handle (lateral to medial on volar surface)



proximal row: (lat to med) Scaphoid, lunate, triquetrium, pisiform,


distal row: trapezium, trapezoid, capitate, hamate

what is the flexor retinaculum attached to?

scaphoid and trapezium

scaphoid and trapezium

What is the contents of the carpal tunnel?

median nn and 9 flexor tendons: (4) FDS, (4) FDP, (1) FPL


 


superficial: FDS 3 & 4, median nn


middle: FDS 2 & 5


Deep: FDP & FPL


transverse carpal ligament (aka flexor retinaculum forms roof of carpal tunnel and carpal bones form floor)

median nn and 9 flexor tendons: (4) FDS, (4) FDP, (1) FPL



superficial: FDS 3 & 4, median nn


middle: FDS 2 & 5


Deep: FDP & FPL


transverse carpal ligament (aka flexor retinaculum forms roof of carpal tunnel and carpal bones form floor)

Which carpal bone is most likely to fracture?

scaphoid


poor blood supply and can frequently develop avascular necrosis

SCAPHOID


poor blood supply and can frequently develop avascular necrosis

Where are the heads of the metacarpals

heads are distal

how many bones and how many joints are in the wrist, hand, and fingers?

bones: 29


joints: 31

bones: 29


joints: 31


(I think Radius and Ulna are included in this)

What is the quantity of movement contributed by the thumb to hand function?

40% of hand's function is contributed by thumb


-(that's almost 1/2)!

what are the arches of the hand?

support the hand for strength and allow prehension


1. longitudinal 


2. metacarpalphalangeal transverse (distal transverse arch)


3. carpal transverse (proximal transverse)


 

support the hand for strength and allow prehension


1. longitudinal


2. metacarpalphalangeal transverse (distal transverse arch)


3. carpal transverse (proximal transverse)


what type of injury limits supination/pronation

damage to mid to distal forearm

what type of joint is the radiocarpal and what bones make it up?

biaxial ellipsoid between radius (concave) and scaphoid and lunate (convex)

BI-AXIAL ELLIPSOID between radius (concave) and scaphoid and lunate (convex)

What stabilizes the radiocarpal joint?

-radial collateral ligament on lateral side


-triangular shaped disc on the ulna (part of triangular fibrocartilage complex (TFCC)) that connected to triquetrium and lunate via ulnar collateral ligament medially`

-RADIAL COLLATERAL LIGAMENT on lateral side


-triangular shaped disc on the ulna (part of triangular fibrocartilage complex [TFCC] that connects to triquetrium and lunate via ulnar collateral ligament medially)

*What is TFCC?

Triangular fibrocartilage complex 


articular disk on distal end of ulna connected via two fibrous laminae:


1. dorsal and palmar ligaments attaching to head of ulna and ulnar styloid process


2. ulnar collateral ligament which attaches to tri...

Triangular fibrocartilage complex


-articular disk on distal end of ulna connected via two fibrous laminae:


1. dorsal and palmar ligaments attaching to head of ulna and ulnar styloid process


2. ulnar collateral ligament which attaches to triquetrum, hamate, and base of 5th metacarpal


and ECU tendon shealth

what is the load bearing ratio of radius to ulna

60:40

What are the motions of the radiocarpal joint?

5 TOTAL: flexion, extension, radial deviation, ulnar deviation, circumduction

What motions occur at intercarpal joint?

small amount of gliding


-dorsal, palmar, and interosseous ligaments stabilize


-pisiform sits on triquetrum and does not participate in gliding


*What articulations makes up the midcarpal joint?

-medially the scaphoid, lunate, triquetrium articulate with hamate and capitate


-laterally the scaphoid articulates with the trapezoid and trapezium


-stabilized by dorsal and palmar ligaments

-medially the scaphoid, lunate, triquetrium articulate with hamate and capitate


-laterally the scaphoid articulates with the trapezoid and trapezium


-stabilized by dorsal and palmar ligaments

What is the functional motion of the scaphoid during wrist motions?

-functions with proximal row of carpals during flexion


-functions with distal row during extension


(* the only thing that may help with this is when you flex your wrist you can get your fingers to go more proximal than when you extend your wrist where they stay more distal)

What dislocation is common in the carpal bones?

anterior dislocation of the lunate resulting in compression of median nn against the flexor retinaculum

anterior dislocation of the LUNATE resulting in compression of median nn against the flexor retinaculum

*What joint does the majority of wrist flexion and wrist extension occur at?

wrist flexion: mid carpal


wrist extension: radiocarpal

what wrist position allows effective hand function?

slight extension

slight extension

*What muscle is most active in grasping?

Extensor carpi radialis brevis ECRB which holds wrist in slight extension

Extensor carpi radialis brevis ECRB which holds wrist in slight extension

*what 3 muscles of the wrist/forearm are active in both wrist flexion and extension to provide dynamic stability?

ECU


EPB


Abd Pollicis longus

*What are the wrist flexors and which is more effective?

FCR and FCU


FCR is more effective


finger flexors can flex wrist (need to be stabilized during MMT)

FCR and FCU


-FCR is more effective


-finger flexors can flex wrist (need to be stabilized during MMT)

*what mm produces radial deviation

ECRB, ECRL, FCR

What mm do ulnar deviation?

ECU, FCU

what are the muscles of the anterior forearm

8 muscles


-muscles that pronate forearm and hand: Pronator quadratus and Pronator teres


-muscles that flex hand: FCU, FCR and palmaris longus


-muscles that flex the digits (FPL, FDP, FDS)


FLEXORS:


*4-1=3


SUPERFICIAL LAYER


1. Pronator teres


2. FCR


3. Palmaris Longus


4. FCU


MIDDLE LAYER


1. FDS


DEEP LAYER


1. FDP


2. FPL


3. Pronator Quadratus

what are the muscles of posterior forearm

11 muscles


-Muscles that extend the wrist: ECRL, ECRB, ECU


-extend medial 4 digits: ED, EI, EDM


-extend the 1st digit (thumb): Abductor pollicus longus, EPB, EPL


EXTENSORS:


6-6


SUPERFICIAL LAYER:


1. Brachioradialis


2. ECRL


3. ECRB


4. Extensor Digitorum


5. Extensor Digiti Minimi


6. ECU


DEEP LAYER:


1. Anconeus


2. Supinator


3. AbPL


4. EPB


5. EPL


6. Extensor Indices




what is the blood supply of the wrist?

radial artery begins in the cubital fossa and travels medially to radial styloid process


-palpation is where radial artery lies on anterior surface of distal radius & lateral to FCR

What injury can damage radial artery?

supracondylar fracture of the elbow can damage radial artery in cubital fossa

what type of joints are the 4 medial CMC joints?


What ligaments provide stability

plane synovial


dorsal, palmar, and interosseous ligament support

-Plane synovial


-Dorsal, palmar, and interosseous ligament support

what injuries are common at the CMC joint?

all CMC joints are susceptible to STRAINS

what type of joint is the thumb CMC

saddle with dorsal, palmar, and lateral ligament support

SADDLE with dorsal, palmar, and lateral ligament support

Where is the intermetacarpal joints?

between 2nd through 4th metacarpal bones


-plane joints held together by ligaments with small amount of gliding motion

between 2nd through 4th metacarpal bones


-plane joints held together by ligaments with small amount of gliding motion

What type of joint is the MCP joints?


what ligaments provided stability

condyloid joints


palmar, transverse and collateral ligaments (tight in flexion)

-Condyloid joints


-Palmar, transverse and collateral ligaments (tight in flexion)

What is unique about the 1st MCP joint?

It can ROTATE which augments function of 1st CMC joint

how many IP joints in each finger?

2 except the thmb

what type of joint are the PIP and DIP?

uniaxial HINGE: flexion and extension

what stabilizes DIP and PIP joints?

PALMAR and COLLATERAL ligaments and a FIBROUS capsule

what happens to IP ligaments in flexion?

they do not become tight (unlike MCP joint flexion in which the collaterals do become tight)

they DO NOT become tight (unlike MCP joint flexion in which the collaterals do become tight)

In general what muscle performance characteristic do the hand extrinsic muscles supply vs the intrinsics?

extrinsics provide POWER


intrinsics provide FINE CONTROL

How much wrist extension is needed for optimal use of the hand?

20-30 deg

what are the 2 types of functional grasps

power grip


precision (prehension) grip

POWER grip


PRECISION (prehension) grip

What is power grip?

exerts force on object to hold against hand


requires FINGER FLEXION and WRIST EXTENSION with ULNAR DEVIATION

what is prehension/precision grip?

used for accurate function with objects held between tips of fingers

what muscles control the thumb?

4 intrinsic (thenar) and 4 extrinsics (forearm)


intrinsic:


OP - opponens pollicis


FPB - flexor pollicis brevis


APB - abductor pollicis brevis


adductor pollicis



extrinsic:


EPL - extensor pollicis longus


EPB - extensor pollicis brevis


FPL - flexor pollicis longus


APL - abductor pollicis longus

what are the muscles of the thenar eminence?

Opponens pollicis


Flexor pollicis brevis FPB


Abductor pollicis brevis APB


innervation: (except deep head of FPB) = median nn

1) Opponens pollicis


2) FPB: Flexor pollicis brevis


3) AbPB Abductor pollicis brevis


innervation: (except deep head of FPB) = median nn

what are the hypothenar muscles?

flexor digiti minimi


abductor digiti minimi


opponens digiti minimi


palmaris brevis

1) flexor digiti minimi


2) abductor digiti minimi


3) opponens digiti minimi


4) palmaris brevis

what muscles extend the IPs and MCPs?

EXTENSOR DIGITORUM


(interossei and lumbricals contribute by incr tension on extensor mechanism to allow ED to extend digits)

What is the function of the EPL?

extends IP and MCP of thumb


causes CMC retroposition

what does the opponens digiti minimi do?

hollows the palm for cupping the hand (e.g. to drink water from glass or grasp cylindrical object)

what does radial nerve damage do to hand/wrist function?

affects ability to maintain functional wrist position and to release an object

what does damage to median nn do to hand/wrist function?

effects flexion of digits on radial side and precision grip

what does damage to ulnar nn do to hand/wrist function?

flexion of digits on ulnar side and power grip