The Upper Limb Flashcards
associated with the lateral side of the neck and thoracic wall
the upper limb
composed of the shoulder, arm, forearm, and hand
the upper limb
what is the upper limb attached to the body by?
by muscles and by a small skeletal attachment at the sternoclavicular joint
significant transitions between the different parts of the limb
The axilla, cubital fossa, and carpal tunnel
irregularly shaped triangle formed by muscles and bones of the shoulder and the lateral surface of the thoracic wall
Axilla
triangular shaped depression formed by muscles anterior to the elbow
cubital fossa
- the gateway to the palm
- Formed by carpal bones and flexor retinaculum
carpel tunnel
used for positioning the hand in space
the upper limb
changes the position of the glenohumeral joint
Movement of the scapula on the thoracic wall
protraction and retraction
sliding
abduction and adduction
rotating
can move in 3 axes
glenohumeral joint
what are the movements at the glenohumeral joint?
- flexion
- extension
- adduction
- abduction
- medial rotation
- lateral rotation
- circumduction
major movements of the elbow
flexion and extension
supinated or pronated by flipping the radius over the ulna at the distal end
the forearm
what are the movements of the wrist?
- abduction
- adducted
- flexed
- extended
- circumducted
allow the hand to be put into a wide range of positions
The combined movements of the shoulder, arm, and forearm
used to grip and manipulate objects generally by flexing fingers against the thumb
the hand
pads of the palmer aspect of the hand have a high density of somatic sensory receptors
the hand as a sensory tool
consist of the scapula, clavicle, and the proximal end of the humerus
bones of the shoulder
articulates medially with the manubrium and laterally with the acromion of the scapula
the clavicle
- the bone of the arm
- the distal end forms the elbow joint (hinge joint) with the bones of the forearm
the humerus
- the bones of the forearm
- the distal ends form the wrist
The radius (lateral) and ulna (medial)
make up the bones of the hand
The carpals, metacarpals, and phalanges
movement between which bones is limited?
the 8 carpal bones is limited, thus they work as a unit
the primary skeletal foundation of the palm
The 5 metacarpals
has greater mobility than the other carpometacarpal joints
The joint of the thumb
saddle joint
the thumb joint
lacks a ligamentous connection to the neighboring metacarpal of the index finger
the metacarpel of the thumb
are distally connected via strong ligaments
Metacarpals II-V
biaxial condylar joints
Metacarpophalangeal joints
what are the movements of the Metacarpophalangeal joints?
- abduction
- adduction
- lexion
- extension
- circumduction
what movements do interphalangeal joints allow?
flexion and extension
what are the muscles that attach the scapula and clavicle to the trunk?
- trapezius
- levator scapulae
- rhomboids
what do other muscles attach?
attach the scapula, clavicle, and body wall to the proximal end of the humerus- pectoralis major and minor, latissimus dorsi, teres major, and deltoid
subscapularis, supraspinatus, infraspinatus, and teres minor connect scapula to humerus and provide support for the glenohumeral joint
the rotator cuff
what compartments are the muscles of the arm and forearm separated into?
- anterior (flexor compartment)
- posterior (extensor compartment)
separated by the humerus and medial and lateral intermuscular septa
Compartments of the arm
separated by a lateral intermuscular septum, radius, ulna, and interosseous membrane
Compartments of the forearm
formed by intrinsic muscles that move the thumb
The thenar eminence of the hand
directly related to the neck
upper limb
lies on each side of the superior thoracic aperture
axillary inlet
pass through the axillary inlet
The major artery, vein, and nerves of the arm
- *formed by:
- Lateral margin of rib 1
- Posterior surface of clavicle
- Superior margin of scapula
- Medial surface of coracoid process of scapula
relationship of upper limb to neck
associated with the back and thoracic wall
Muscles that attach the bones of the shoulder to the trunk
what are the muscles that attach the bones of the shoulder to the trunk?
- trapezius
- levator scapulae
- rhomboid major rhomboid minor latissimus dorsi
overlays the pectoralis major which forms most of the anterior wall of the axilla
the breast
often extends up into the axilla
axillary process of the breast
where does the Lymphatic drainage from the lateral and superior sides of the breast drain into?
the axilla
arise from major axillary vessels
arteries and veins that supply and drain the breast
Innervation of the upper limb is by?
brachial plexus
formed by the anterior rami of cervical spinal nerves (C5 to C8 and T1)
brachial plexus
gives rise to the musculocutaneous (C5-C7), median (C6-C8, T1), radial (C5-C8, T1), and ulnar (C8-T1) nerves
the brachial plexus
often tested for sensation in order to test for cervical spinal nerve damage
Dermatomes of the upper limb
tested by joint movement in order to test for cervical spinal nerve damage
Myotomes of the upper limb
Each major muscle compartment in the arm and forearm and each intrinsic muscle of the hand is predominantly innervated by what?
1 nerve
also predominantly innervated by 1 nerve
different dermatomes
passes posteriorly around the surgical neck of the humerus
the axillary nerve
pass diagonally around the posterior side of the humerus
radial nerve
passes posteriorly to a bony protrusion on the medial side of the distal end of the humerus
the ulnar nerve
used to access a patients vascular system
Large veins in the superficial fascia of the upper limb
originate from the dorsal venous network on the back of the hand
cephalic and basilic veins
originates over the anatomical snuff box and extends proximally into the axilla by passing through the clavipectoral (deltopectoral) triangle
cephalic vein
connect at the elbow by the median cubital vein
The cephalic and basilic veins
positioned at right angles to the other fingers
the thumb
brings the thumb across the palm
flexion
moves the thumb away from the fingers at right angles
abduction
brings the thumb into opposition to the other fingers
Slight rotation of metacarpal I
vital for normal hand function
An opposing thumb
the region of upper limb attachment to the trunk
the shoulder
consists of the clavicle and scapula- making up the pectoral girdle
the shoulder
the only bony attachment between the shoulder and the trunk
clavicle
It is an S-shaped bone with an acromial end (lateral) and a sternal end (medial)
clavicle
Each end has a facet for articulation with either the acromion or the manubrium/1st rib
clavicle
has conoid tubercle and trapezoid line for coracoclavicular ligament attachment
The inferior surface of the lateral third (of clavicle)
- Large, flat, and triangular
- Has 3 angles, 3 borders, 2 surfaces, 3 processes
scapula
what are the angles of the scapula?
- lateral (marked by glenoid cavity)
- superior and inferior
what are the borders of the scapula?
- lateral
- medial
- superior
what are the surfaces of the scapula?
- costal and posterior
- posterior
- costal surface
what is the posterior surface of the scapula divided into?
supraspinous fossa and infraspinous fossa by scapula spine
what is the costal surface of the scapula characterized by?
subscapular fossa
where the head of the humerus articulates with the scapula
the glenoid cavity
attachment point of long head of triceps brachii
Infraglenoid tubercle
attachment point of long head of biceps brachii
Supraglenoid tubercle
a projection of the scapular spine that arches over glenohumeral joint
the acromion
between lateral angle and scapular spine
greater scapular notch
hook like structure
coracoid process
medial to the root of the coracoid process
Suprascapular notch
Consists of the head, anatomical neck, greater and lesser tubercles, surgical neck, and the superior half of the shaft
proximal humerus
articulates with glenoid cavity
head of proximal humerus
connects head to shaft
anatomical neck of proximal humerus
superior, middle, inferior facets
greater tubercle
supraspinous muscle attachment
superior greater tubercle
infraspinous muscle attachment
middle greater tubercle
teres minor muscle attachment
inferior greater tubercle
subscapularis muscle attachment
lesser tubercle
houses tendon of long head of biceps brachii
intertubercular sulcus
what are the points of attachment on the shaft of the proximal humerus?
lateral and medial lip and floor of intertubercular sulcus, deltoid tuberosity, attachment of coracobrachialis
what are the 3 joints of the shoulder complex?
- Sternoclavicular
- acromioclavicular
- glenohumeral
sternum and clavicle
sternoclavicular joint
acromion and clavicle
acromioclavicular joint
glenoid cavity and humerus head
glenohumeral joint
enable the scapula to be positioned over a wide range of positions, increasing reach
The sterno- and acromioclavicular joints
occurs between proximal end of clavicle and clavicular notch of manubrium
Sternoclavicular joint (synovial)
separates 2 compartments of shoulder joints
articular disc
reinforced by capsule and 4 ligaments
shoulder joints
what are the ligaments of the shoulder joints?
- Anterior and posterior sternoclavicular ligaments
- Interclavicular ligaments
- Costoclavicular ligaments
small synovial joint between distal end of clavicle and acromion process
Acromioclavicular joint
what is the acromioclavicular joint surrounded by?
joint capsule
what is the acromioclavicular joint reinforced by?
-Acromioclavicular ligament
-Coracoclavicular ligament
~Trapezoid ligament
~Conoid ligament
a synovial ball and socket joint between the head of the humerus and the glenoid cavity
glenohumeral joint
a multiaxial joint with a wide range of movement at the cost of skeletal stability
glenohumeral joint
what is the glenohumeral joint supported by?
the rotator cuff, long head of biceps brachii, related bony processes, and extracapsular ligaments
deepened by the glenoid labrum (a fibrocartilagenous collar)
glenoid cavity
attaches to the margins of the articular surfaces and lines the fibrous membrane
synovial membrane
wraps around the tendon of the long head of biceps brachii
synovial sheath
protrudes through the fibrous membrane to produce bursae which lie between surrounding muscles and the fibrous membrane (subtendinous bursa of subscapularis is the most consistent)
synovial membrane
attaches to the margin of the glenoid cavity, outside the attachment of the glenoid labrum and the long head of the biceps brachii, and to the anatomical neck of the humerus
fibrous membrane
aids in adduction of shoulder joint
redundant synovial membrane
accommodates abduction in shoulder joint
redundant capsule
where is the fibrous membrane thickened?
- Superior, middle, and inferior glenohumeral ligaments
- coracohumeral
- transverse humeral ligaments
provided by ligaments and rotator cuff muscles
joint stability
blend with the joint capsule, forming a musculotendinous collar
Ligaments of the supraspinatus, infraspinatus, teres minor, and subscapularis muscles
lies between the acromion (or deltoid muscle) and supraspinatus
The subacromial bursa (subdeltoid)
where does the blood supply to the glenohumeral joint come from?
the posterior circumflex and suprascapular artery
what is the glenohumeral joint innervated by?
branches from the posterior cord of brachial plexus, and from the suprascapular, axillary, and lateral pectoral nerves
The 2 most superficial muscles of the shoulder
trapezius and deltoid
attaches the scapula and clavicle to the trunk
trapezius
attaches the scapula and clavicle to the humerus
deltoid
what are the opposing surfaces and margins that the trapezius and deltoid attach to?
opposing surfaces and margins on the spine of the scapula, acromion, and clavicle
deep to the trapezius and deltoid
levator scapula, rhomboid major and minor
position the scapula on the trunk
levator scapula, rhomboid major and minor
has extensive origins on the axial skeleton- includes sites on the skull and vertebrae (CI to TXII)
trapezius
attaches to the shoulder in a U-shape (scapula spine, acromion, and clavicle)
trapezius
originates along the U-shape line of bone and inserts on the deltoid tuberosity of humerus
deltoid
originates on transverse processes of CI and CIV and inserts on medial border of scapula
levator scapula
attach medially to the vertebral column and descend laterally to attach to the medial border of the scapula inferior to levator scapula
rhomboid minor and major
**ORIGINATES AT: Superior nuchal line, external occipital protuberance, medial margin of the ligamentum nuchae, spinous processes of CVII to TXII and the related supraspinous ligaments
trapezius
**INSERTION AT: Superior edge of the crest of the spine of the scapula, acromion, posterior border and lateral 1/3 of clavicle
trapezius
**INNERVATED BY: Motor spinal part of accessory nerve (XI). Sensory (proprioception) anterior rami of C3 and C4
trapezius
**FUNCTION: Powerful elevator of the scapula; rotates the scapula during abduction of humerus above horizontal; middle fibers retract scapula; lower fibers depress scapula
trapezius
**ORIGIN: Inferior edge of the crest of the spine of the scapula, lateral margin of the acromion, anterior border of the lateral 1/3 of clavicle
deltoid
**INSERTION AT: Deltoid tuberosity of humerus
deltoid
**INNERVATED BY: Axillary nerve (C5, C6)
deltoid
**FUNCTION: Major abduction of arm (abducts arm beyond initial 15⁰ done by supraspinatus); clavicular fibers assist in flexing the arm; posterior fibers assist in extending the arm
deltoid
**ORIGIN: Transverse processes of CI and CII vertebrae and posterior tubercles of the transverse processes of CIII and CIV vertebrae
levator scapulae
**INSERTION: Posterior surface of medial border of scapula from superior angle to root of spine of the scapula
levator scapulae
**INNERVATION: Branches directly from anterior rami of C3 and C4 spinal nerves and by branches (C5) from dorsal scapular nerve
levator scapulae
**FUNCTION: elevates the scapula
levator scapulae
**ORIGIN: Lower end of ligamentum nucha and spinous processes of CVII and TI vertebrae
rhomboid minor
**INSERTION: Posterior surface of medial border of scapula to root of the spine of the scapula
rhomboid minor
**INNERVATION: Dorsal scapular nerve (C4, C5)
rhomboid minor
**FUNCTION: Elevates and retract the scapula
rhomboid minor
**ORIGIN: Spinous processes of TII-TV vertebrae and intervening supraspinpus ligaments
rhomboid major
**INSERTION: Posterior surface of medial border of scapula from the root of the spine to the inferior angle
rhomboid major
**INNERVATION: Dorsal scapular nerve (C4, C5)
rhomboid major
**FUNCTION: elevates and retracts the scapula
rhomboid major
Contains 4 muscles that extend between the scapula and proximal end of the humerus
posterior scapula region
what are the 4 muscles of the scapula region?
- Supraspinatus
- infraspinatus
- teres minor
- teres major
originate from large fossa above and below the scapula spine respectively
Supraspinatus and infraspinatus
extends between infraglenoid tubercle and the olecranon (ulna)
Long head of triceps brachii
Gateways to the posterior scapula region
suprascapular notch from the neck for suprascapular nerve
from more anterior regions for axillary nerve and posterior circumflex humeral artery
Quadrangular space
has circumflex scapular artery
triangular space
radial nerve an profunda brachii artery (deep artery of arm)
triangular interval
2 major nerves of the posterior scapula region that both arise from the brachial plexus
axillary and suprascapular nerves
passes through the suprascapular foramen and innervates the supraspinatus and then passes through the greater scapular notch and innervate the infraspinatus
suprascapular nerve
innervates the deltoid and teres minor
axillary nerve
**ORIGIN: Medial 2/3 of the supraspinous fossa of the scapula and the deep fascia that covers the muscle
supraspinatus muscle
**INSERTION: Most superior facet on the greater tubercle of the humerus
supraspinatus muscle
**INNERVATION: Suprascapular nerve (C5, C6)
supraspinatus muscle
**FUNCTION: Rotator cuff muscle; initiation of abduction of arm to 15⁰ at glenohumeral joint
supraspinatus muscle
**ORIGIN: Medial 2/3 of the infraspinous fossa of the scapula and the deep fascia that covers the muscle
infraspinatus muscle
**INSERTION: Middle facet on posterior of the greater tubercle of the humerus
infraspinatus muscle
**INNERVATION: Suprascapular nerve (C5, C6
infraspinatus muscle
**FUNCTION: Rotator cuff muscle; lateral rotation of arm at the glenohumeral joint
infraspinatus muscle
**ORIGIN: Upper 2/3 of a flattened strip of bone on the posterior surface of the scapula immediately adjacent to the lateral border of the scapula
teres minor muscle
**INSERTION: inferior facet on the posterior surface of the greater tubercle of the humerus
teres minor muscle
**INNERVATION: Axillary nerve (C5, C6)
teres minor muscle
**FUNCTION: Rotator cuff muscle; lateral rotation of arm at the glenohumeral joint
teres minor muscle
**ORIGIN: Elongate oval area on the posterior surface of the inferior angle of the scapula
teres major muscle
**INSERTION: Medial lip of the intertubercular sulcus on the anterior surface of the humerus
teres major muscle
**INNERVATION: Inferior subscapular nerve (C5, C6, C7)
teres major muscle
**FUNCTION: Medial rotation and extension of the arm at the glenohumeral joint
teres major muscle
**ORIGIN: Infraglenoid tubercle on scapula
long head of triceps brachii muscle
**INSERTION: Common tendon of insertion with medial and lateral heads on the olecranon process of ulna
long head of triceps brachii muscle
**INNERVATION: Radial nerve (C6, C7, C8)
long head of triceps brachii muscle
**FUNCTION: Extension of the forearm at the elbow joint; accessory adductor and extensor of the arm at the glenohumeral joint
long head of triceps brachii muscle
what are the 3 major arteries of the posterior scapula region?
- suprascapular artery
- posterior circumflex humeral artery
- circumflex scapular artery
arises from thyrocervical trunk and usually passes superior to suprascapular notch
Suprascapular artery
originates from axillary
Posterior circumflex humeral artery
branch from subscapular artery which arises from the axillary
Circumflex scapular artery
gateway to the arm
axilla
- Formed by clavicle, scapula, upper thoracic wall, the humerus, and related muscles
- It has 4 sides, an inlet, and a floor
axilla
continuous with the neck and the floor opens into the arm
axillary inlet
All structures that pass in or out of the upper limb pass through the…..
axilla
is formed by the pectoralis major, and underlying pectoralis minor and subclavius muscles, and the clavipectoral fascia
anterior wall of the axilla
- small muscle that passes between the clavicle and rib I
- part of anterior wall of axilla
subclavius
- small triangular muscle that passes from the thoracic wall to the coracoid process
- part of anterior wall of axilla
pectoralis minor
-thick sheet of connective tissue that connects the clavicle to the floor of the axilla and encloses pectoralis minor and subclavius
clavipectoral fascia
**ORIGIN: Clavicular head- anterior surface of the medial ½ of clavicle; sternocostal head- anterior surface of sternum; first 7 costal cartilages; sternal end of 6th rib; aponeurosis of external oblique
pectorlis major muscle
**INSERTION: Lateral lip of intertubercular sulcus of humerus
pectoralis major muscle
**INNERVATION: Medial and lateral pectoral nerves; clavicular head (C5, C6); sternocostal part (C6, C7, C8, T1)
pectoralis major muscle
**FUNCTION: Flexion, adduction, and medial rotation of arm at the glenohumeral joint; clavicular head- flexion of extended arm; sternocostal head- extension of flexed arm
pectoralis major muscle
**ORIGIN: First rib at junction between rib and costal cartilage
subclavius muscle
**INSERTION: Grove on inferior surface of middle 1/3 of clavicle
subclavius muscle
**INNERVATION: Nerve of subclavius (C5, C6)
subclavius muscle
**FUNCTION: Pulls tip of shoulder down; pulls clavicle medially to stabilize sternoclavicular joint
subclavius muscle
**ORIGIN: Anterior surface and superior borders of ribs III to V; and from deep fascia overlying the related intercostal space
pectoralis minor muscle
**INSERTION: Coracoid process of scapula (medial border and upper surface)
pectoralis minor
**INNERVATION: Medial pectoral nerve (C5, C6, C7, C8, T1)
pectoralis minor
**FUNCTION: Pulls tip of shoulder down; protracts scapula
pectoralis minor muscle
Formed by upper thoracic wall (ribs and related intercostal muscles) and the serratus anterior
medial wall of axilla
innervated by the long thoracic nerve
serratus anterior of the medial wall of axilla
passes through the medial wall and into the axilla where it communicates with a branch from the brachial plexus
intercostobrachial nerve of medial wall of axilla
**ORIGIN: Lateral surfaces of the upper 8-9 ribs and the deep fascia overlying the related intercostal spaces
serratus anterior muscle
**INSERTION:Costal surface of medial border of scapula
serratus anterior muscle
**INNERVATION: Long thoracic nerve (C5, C6, C7)
serratus anterior muscle
**FUNCTION: Protraction and rotation of the scapula; keeps medial border and inferior angle of scapula opposed to thoracic wall
serratus anterior muscle
Narrow and formed entirely by the intertubercular sulcus of the humerus
lateral wall of axilla
inserts on the lateral lip of the sulcus
pectoralis major muscle
attach to the floor and medial lip of the sulcus respectively
latissimus dorsi and teres major
Formed by the costal surface of the scapula, subscapularis muscle, distal parts of the latissimus dorsi and teres major muscles, and proximal parts of the long head of the triceps brachii
posterior wall of axilla
allow structures to pass between the axilla, posterior scapular region and posterior compartment of the arm
Gaps between the muscles
**ORIGIN: Medial 2/3 of subscapular fossa
subscapularis muscle
**INSERTION: Lesser tubercle of humerus
subscapularis muscle
**INNERVATION: Upper and lower subscapular nerves (C5, C6, C7)
subscapularis muscle
**FUNCTION: Rotator cuff; medial rotation of the arm at the glenohumeral joint
subscapularis muscle
**ORIGIN: Elongate oval area on the posterior surface of the inferior angle of scapula
teres major muscle
**INSERTION: Medial lip of intertubercular sulcus on the anterior surface of the humerus
teres major muscle
**INNERVATION: Lower subscapular nerve (C5, C6, C7)
teres major muscle
**FUNCTION: Medial rotation and extension of the arm at the glenohumeral joint
teres major muscle
**ORIGIN: Spinous processes of lower 6 thoracic vertebrae and related interspinous ligaments; via the thoracolumbar fascia on the spinous processes of the lumbar vertebrae, related interspinous ligaments, and iliac crest, lower 3-4 ribs
latissimus dorsi muscle
**INSERTION: Floor of intertubercular sulcus
latissimus dorsi muscle
**INNERVATION: Thoracodorsal nerve (C6, C7, C8)
latissimus dorsi muscle
**FUNCTION: Adduction, medial rotation and extension of the arm at the glenohumeral joint
latissimus dorsi muscle
formed by fascia and a dome of skin
axilla floor
contains major blood vessels, nerves, and lymphatics of the arm
axillary sheath
contains the proximal parts of the biceps brachii and coracobrachialis muscles, the axillary process of the breast, and collections of lymph nodes
axilla
short head originates from the coracoid process
biceps brachii
originates as a tendon that attaches to the supraglenoid tubercle of the scapula
long head of biceps brachii
originates on the coracoid process of the scapula and inserts onto the medial aspect of humerus
coracobrachialis
supplies the walls of the axilla and related regions
axillary artery
As the subclavian passes the lateral margin of rib I it becomes the …..
axillary artery
As the axillary artery passes the inferior margin of the teres major muscle it becomes the …….
brachial artery
divides the axillary artery into 3 parts (1st, 2nd, and 3rd)
pectoralis minor muscle
how many branches arise from the axillary artery?
6 branches
1st part of axillary artery
superior thoracic artery
2nd part of axillary artery
thoraco-acromial artery and lateral thoracic artery
3rd part of axillary artery
Subscapular, anterior, and posterior circumflex arteries
Begins at the lower margin of the teres major and is a continuation of the basilic vein
axillary vein
where does the axillary vein pass?
Passes through the axilla medial to the axillary artery
which tributaries of the axillary vein do not follow the branches of the axillary artery?
the brachial veins and cephalic vein
- somatic plexus formed by anterior rami (C5-T1)
- Made up of roots, trunks, divisions, and cords
brachial plexus
originate from the brachial plexus
All major nerves of the arm
where is the brachial plexus located proximally?
Proximally it is posterior to the axillary artery
where is the brachial plexus located distally?
Distally it surrounds the axillary artery
The roots are made up of anterior rami (C5-T1)
brachial plexus
pass laterally over rib I and are formed by unions of roots
trunks of brachial plexus
what do the trunks of the brachial plexus divide into?
anterior and posterior divisions
forms from union of upper and middle anterior trunks
lateral cord of brachial plexus
forms from union of all posterior trunks
posterior cord of brachial plexus
forms from remaining anterior trunk
medial cord of brachial plexus
where do lymphatics from the upper arm drain into?
the axilla
receive drainage from regions of the: upper back and shoulder, lower neck, chest, upper anterolateral abdominal wall, and 75% of the mammary gland
axillary nodes
how are the 20-30 axillary nodes divided?
humeral (lateral), pectoral (anterior), subscapular (posterior), central, and apical
- in some cases penetrates the deep fascia and passes into the axilla
- rarely reaches as high as the apex of the axilla
axillary process of the mammary gland
the region between the shoulder and the elbow joint
the arm
- Superiorly it communicates with the axilla
- inferiorly important structures pass through the cubital fossa
the arm
how are the muscles of the arm divided?
divided into posterior and anterior compartments by the humerus and the intermuscular septum
flex the elbow joint
muscles in the anterior compartment of the arm
extend the elbow joint
muscles in the posterior compartment of the arm
triangular with anterior, lateral, and medial borders and anterolateral, anteromedial, and posterior surfaces
humerus
has various markings associated with muscle attachment points
posterior surface of the humerus
houses the radial nerve and profunda brachii artery
radial groove of humerus
becomes flattened into the lateral and medial supraepicondylar ridges
distal end of humerus
- part of distal end of humerus
- has 2 parts (capitulum & trochlea)
condyle
articulates with the radius & part of condyle
capitulum
articulates with ulna & part of condyle
trochlea
lie adjacent and somewhat superior to the trochlea and capitulum
lateral and medial epicondyles
how many fossa occur superior to the condyle?
3
is superior to the capitulum
radial fossa
superior to the trochlea
coronoid fossa
superior to the trochlea on the posterior sides
olecranon fossa
consists of the head, neck, and radial tuberosity
proximal end of the radius
the roughened attachment point for the biceps brachii
radial tuberosity
runs across the shaft of the radius from the radial tuberosity
oblique line
consists of olecranon, coronoid process, trochlear notch, radial notch, supinator crest, tuberosity
proximal end of ulna
large projection of bone & part of proximal end of the ulna
olecranon
forms the trochlear notch along with the olecranon
coronoid process
obvious semilunar notch
trochlear notch
articulation point for the radius
radial notch
attachment site for brachialis
tuberosity of ulna
what are the muscles of the anterior compartment of the arm?
- coracobrachialis
- biceps brachii
- brachialis
extends from the tip of the coracoid process to the medial side of the midshaft of the humerus
Coracobrachialis
has 2 heads- short head- originates from coracoid process, long head originates as a tendon from the supraglenoid tubercle of scapula, the biceps inserts onto the radial tuberosity
biceps brachii
originates from distal half of anterior aspect of humerus, inserts onto the ulna tuberosity
brachialis
*ORIGIN: Apex of coracoid process
Coracobrachialis muscle
*INSERTION: Linear roughening on midshaft of humerus on medial side
Coracobrachialis muscle
*INNERVATION: Musculocutaneous (C5, C6, C7)
Coracobrachialis muscle
*FUNCTION: Flexor of arm at the glenohumeral joint
Coracobrachialis muscle
*ORIGIN:Long head- supragenoid tubercle of scapula; short head- apex of coracoid process
biceps brachii muscle
*INSERTION: radial tuberosity
biceps brachii muscle
*INNERVATION: Musculocutaneous (C5, C6, C7)
biceps brachii muscle
*FUNCTION: Powerful flexor of the forearm at the elbow joint and supinator of the forearm; accessory flexor of the arm at glenohumeral joint
biceps brachii muscle
*ORIGIN: Anterior aspect of humerus (medial and lateral surface) and adjacent intermuscular septum
brachialis muscle
*INSERTION: Tuberosity of the ulna
brachialis muscle
*INNERVATION: Musculocutaneous (C5, C6); small contribution from radial nerve to lateral part of muscle
brachialis muscle
*FUNCTION: Powerful flexor of the forearm at the elbow joint
brachialis muscle
what is the only muscle in the posterior compartment of the arm?
triceps brachii
what are the 3 heads of the triceps?
- long head
- medial head
- lateral head
originates from infraglenoid tubercle of scapula
long head of the triceps
originates from the extensive area of the posterior surface of the shaft of the humerus inferior to the radial groove
medial head of the triceps
originates from linear roughening superior to radial groove
lateral head of the triceps
where do all the triceps head insert?
insert on the superior surface of the olecranon via a large tendon
*ORIGIN: Long head- infraglenoid tubercle of scapula medial head- posterior surface of humerus lateral head- posterior surface of humerus
triceps brachii muscle
*INSERTION: olecranon
triceps brachii muscle
*INNERVATION: Radial nerve (C6, C7, C8)
triceps brachii muscle
*FUNCTION: Extension of the forearm at the elbow joint; long head can also extend and adduct the arm at the shoulder joint
triceps brachii muscle
is the major artery of the arm and is found in the anterior compartment
brachial atery
starts at the inferior margin of the teres major
brachial artery
is the largest branch of the brachial artery and poses into the posterior compartment
profunda brachii artery
- branches off the brachial artery
- passes posteriorly in the radial groove, humeral nutrient artery, and ulnar collateral arteries
profunda brachii
branches to posterior circumflex humeral artery, radial and middle collateral arteries
Branches off the profunda brachii artery
follow the brachial artery and join either the basilic or axillary vein
paired brachial veins
the 2 large subcutaneous veins located in the arm
the basilic and cephalic veins
what are the nerves of the anterior compartment of the arm?
- musculocutaneous nerve
- median and ulnar nerves
- enters the arm by passing through the coracobrachialis muscle and continues distally in the plane between the biceps brachii and brachialis muscles
- provides motor innervation for the anterior muscle compartment
musculocutaneous nerve
have no major branches in the arm
median and ulnar nerves
what are the nerves of the posterior compartment of the arm?
- radial nerve
- inferior and posterior lateral cutaneous branches
arises from the posterior cord of the brachial plexus and runs along the radial groove with the profunda brachii artery into the posterior compartment
radial nerve
innervates the triceps brachii muscle (the only muscle in the posterior arm compartment) and muscles of the forearm
radial nerve
innervate skin on the posterior arm and forearm
The inferior and posterior lateral cutaneous branches of the radial nerve
a complex joint involving 3 separate articulations which share a common synovial cavity
elbow joint
form the main hinge joint of the elbow
The joints between the trochlear notch of the ulna and the trochlea of the humerus and between the radial head and capitulum of the humerus
form the radio-ulna joint
The joint between the radial head and the radial notch of the ulna
involved in supination and pronation
radio-ulnar joint
originates along the edges of the articular cartilage and lines of the radial, coronoid, and olecranon fossae
synovial membrane of elbow joint
found in the fossa and separate the fibrous and synovial membranes in these same regions
fat pads
how are fat pads moved?
moved out of the way by the brachialis and triceps brachii that are attached to the fibrous membrane in these regions
overlays the synovial membrane and encloses the elbow joint
fibrous membrane
what does the fibrous membrane attach to?
- the medial epicondyle, and the margins of the olecranon, coronoid, and radial fossae of the humerus
- the coronoid and olecranon processes of ulna
thickened medially and laterally into ulnar and radial collateral ligaments
fibrous membrane
cuffs the radius and blends with the radial collateral ligament
anular ligament
allows rotation of radial head
sacciform recess
Formed by brachioradialis and pronator teres (lateral and medial boundaries) and the brachialis (floor)
cubital fossa
what are the major contents of the cubital fossa?
- tendon of biceps brachii
- brachial artery
- median nerve
passes along the lateral margin under the brachioradialis muscle
radial nerve of cubital fossa
lie along the roof of the cubital fossa roof
The median cubital vein, medial and lateral cutaneous nerves
extends between the elbow and wrist joints
forearm
what do most major structures go through that pass into the forearm?
pass through the cubital fossa (except ulnar nerve)
what do most major structures go through that pass into the hand?
the carpel tunnel (except radial artery)
separate the anterior and posterior muscle compartments of the forearm
The radius, ulnar, interosseous membrane, and lateral intermuscular septum
is smaller proximally and larger distally, where it forms the wrist joint
radius
triangular in cross section formed by: lateral, posterior, anterior surfaces and lateral, posterior, interosseous borders
shaft of radius
acts as a pulley for the extensor pollicis tendon
dorsal tubercle of radius
extends distally
radial styloid process
found on the distal end of the radius
two articulation facets
triangular in cross section formed by: anterior, posterior, medial surfaces and anterior, posterior, interosseous borders
ulna
has a roughening for attachment of pronator quadratus
anterior surface of ulna
extends distally
ulnar styloid process
form the radio-ulnar joint of the forearm
Distally the head of the ulnar and the end of the radius
separates the radio-ulnar from the wrist joint
articular disc of forearm
- runs between the ulnar and radius without restricting pronation and supination
- allows transfer of forces from the radius to the ulnar and ultimately to the humerus
interosseous membrane
- occur entirely in the forearm
- Involves rotation of radius at elbow and movement of radius over ulnar at distal end
pronation and supination
spins on the capitulum, radial notch, and adjacent joint capsule
radial head
distally,…………., slides anteriorly over the convex surface of the ulnar head
the ulnar notch of the radius
hold the bones in place during movements (pronation and supination)
anular ligament, interosseous membrane, articular disc
supination muscles
biceps brachii and supinator
pronation muscles
pronator teres and quadratus
- provides some abduction of the proximal end of the ulnar during pronation
- This maintains the position of the palm over the central axis during pronation
anconeus
how are the muscles of the anterior (flexor) compartment divided?
divided into superficial, intermediate, and deep layers
what are the muscles of the anterior (flexor) compartment associated with?
movement of wrist joint, flexion of fingers and thumb, and pronation
originate on the medial epicondyle of humerus
all 4 muscles in the superficial layer
muscles of superficial layer of anterior (flexor) compartment
- pronator teres
- flexor carpi radialis
- palmaris longus
- flexor carpi ulnaris
*ORIGIN: Humeral head- medial epicondyle of humerus; ulnar head- olecranon and posterior border of ulna
flexor carpi ulnaris muscle
*Insertion: Pisiform bone, and then via pisohamate and pisometacarpal ligaments into the hamate and base of metacarpal V
flexor carpi ulnaris muscle
*INNERVATION: Ulnar nerve (C7, C8, T1)
flexor carpi ulnaris muscle
*FUNCTION: Flexes and adducts the wrist
flexor carpi ulnaris muscle
*ORIGIN: Medial epicondyle of humerus
palmaris longus muscle
*INSERTION: Palmar aponeurosis of hand
palmaris longus muscle
*INNERVATION: Median nerve (C7, C8)
palmaris longus muscle
*FUNCTION: Flexes wrist joint and resists shearing forces when gripping
palmaris longus muscle
*ORIGIN: Medial epicondyle of humerus
flexor carpi radialis
*INSERTION: Base of metacarpal II and III
flexor carpi radialis
*INNERVATION: Median nerve (C6, C7)
flexor carpi radialis
*FUNCTION: Flexes and abducts the wrist
flexor carpi radialis
*ORIGIN: Humeral head- medial epicondyle and adjacent supra-epicondylar ridge; ulnar head- medial side of coronoid process
pronator teres
*INSERTION: Roughening on lateral surface, midshaft, of radius
pronator teres
*INNERVATION: Median nerve (C6, C7)
pronator teres
*FUNCTION: pronation
pronator teres
consists of 1 muscle (large flexor digitorum superficialis)
intermediate layer of anterior compartment
- muscle with two heads
- part of intermediate layer
large flexor digitorum superficialis
pass deep to, and between the 2 heads of the large flexor digitorum superficialis
median nerve and ulnar artery
distally, the……….forms 4 tendons which pass through the carpal tunnel onto the 4 fingers
flexor digitorum superficialis
insert on the margins of the middle phalanx
tendons that pass through carpel tunnel onto the 4 fingers
*ORIGIN: Humero-ulnar head-medial epicondyle of humerus and adjacent margin of coronoid process; radial had- oblique line of radius
flexor digitorum superficialis muscle
*INSERTION:Four tendons, which attach to the palmer surfaces of the middle phalanges of the index, middle, ring, and little fingers
flexor digitorum superficialis muscle
*INNERVATION: Median nerve (C8, T1)
flexor digitorum superficialis muscle
*FUNCTION: flexes proximal interphalangeal joints of the index, middle, ring, and little fingers; can also flex metacarpophalangeal joints of the same finger and the wrist joint
flexor digitorum superficialis muscle
what are the muscles of the deep layer of the anterior compartment?
- flexor digitorum profundus
- flexor pollicis longus
- pronator teres
gives rise to 4 tendons that pass through the carpal tunnel and onto the 4 fingers
flexor digitorum profundus
pass through the split in the tendons of the flexor digitorum superficialis and insert onto the base of the distal phalanges
tendons from the flexor digitorum profundus
forms a single tendon that passes through the carpal tunnel and onto the base of the distal phalanx of the thumb
flexor pollicis longus
*ORIGIN: Anterior and medial surfaces of ulna and anterior medial half of interosseous membrane
Flexor digitorum profundus muscle
*INSERTION: 4 tendons, which attach to the palmer surfaces of the distal phalanges of the index, middle, ring, and little fingers
Flexor digitorum profundus muscle
*INNERVATION: Lateral half by median nerve (anterior interosseous nerve); medial half by ulnar nerve (C8, T1)
Flexor digitorum profundus muscle
*FUNCTION: Flexes distal interphalangeal joints of the index, middle, ring, and little fingers; can also flex metacarpophalangeal joints of the same fingers and the wrist
Flexor digitorum profundus muscle
*ORIGIN: Anterior surface of radius and radial half of interosseous membrane
flexor pollicis longus muscle
*INSERTION: Palmer surface of base of distal phalanx of thumb
flexor pollicis longus muscle
*INNERVATION: Median nerve (anterior interosseous nerve)(C7, C8)
flexor pollicis longus muscle
*FUNCTION: Flexes interphalangeal joint of the thumb; can also flex metacarpophalangeal joint of the thumb
flexor pollicis longus muscle
*ORIGIN: Linear ridge on distal anterior surface of ulna
pronator quadratus muscle
*INSERTION: Distal anterior surface of radius
pronator quadratus muscle
*INNERVATION: Median nerve (anterior interosseous nerve) (C7, C8)
pronator quadratus muscle
*FUNCTION: pronation
pronator quadratus muscle
where are the largest arteries in the forearm?
in the anterior compartment and pass distally to supply the hand and give off branches to the posterior compartment
leaves the forearm and passes around the lateral side of the wrist and gives rise to: radial recurrent, superficial and deep palmar arch of the hand along the way
radial artery
passes on the medial side of the arm and into the wrist giving rise to: ulnar recurrent, common interosseous (posterior and anterior), dorsal and palmer carpal branches
ulnar artery
nerves of the anterior compartment of the forearm
the median and ulnar nerves and the superficial branch of the radial nerve
innervates most of the muscles of the anterior compartment and gives off anterior interosseous nerve and palmar branches
median nerve of forearm
innervates flexor carpi ulnaris and part of flexor digitorum profundus and gives off muscular, dorsal, and palmar branches
ulnar nerve of forearm
bifurcates into deep (mostly motor and innervates posterior compartment) and superficial (sensory) branches
radial nerve of forearm
occur in superficial and deep layers and move the wrist, extend the fingers and thumb, and supinate
muscles in posterior compartment of forearm
are innervated by the radial nerve and originate on the supraepicondylar ridge and lateral epicondyle of the humerus
7 superficial muscles of posterior compartment of forearm
which muscles extend as tendons into the hand?
all but the brachioradialis and anconeus
*ORIGIN: Proximal part of lateral supraepicondylar ridge of humerus and adjacent intermuscular septum
Brachioradialis
muscle
*INSERTION: Lateral surface of distal end of radius
Brachioradialis
muscle
*INNERVATION: Radial nerve (C5, C6)
Brachioradialis
muscle
*FUNCTION: Accessory flexor of elbow joint when forearm is midpronated
Brachioradialis
muscle
*ORIGIN: Distal part of lateral supraepicondylar ridge of humerus and adjacent intermuscular septum
Extensor carpi radialis longus muscle
*INSERTION: Dorsal surface of base of metacarpal II
Extensor carpi radialis longus muscle
*INNERVATION: Radial nerve (C6, C7)
Extensor carpi radialis longus muscle
*FUNCTION: Extends and abducts the wrist
Extensor carpi radialis longus muscle
*ORIGIN: Lateral epicondyle of humerus and adjacent intermuscular septum
Extensor carpi radialis brevis muscle
*INSERTION: Dorsal surface of base of metacarpal II and III
Extensor carpi radialis brevis muscle
*INNERVATION: Deep branch of radial nerve (C7, C8)
Extensor carpi radialis brevis muscle
*FUNCTION: Extends and abducts the wrist
Extensor carpi radialis brevis muscle
*ORIGIN: Lateral epicondyle of humerus and adjacent intermuscular septum and deep fascia
Extensor digitorum
muscle
*INSERTION: 4 tendons which insert via extensor hoods into the dorsal aspects of the base of the middle and distal phalanx of the fingers
Extensor digitorum
muscle
*INNERVATION: Posterior interosseous nerve (C7, C8)
Extensor digitorum
muscle
*FUNCTION: Extends the index, middle, ring, and little fingers; can also extend the wrist
Extensor digitorum
muscle
*ORIGIN: Lateral epicondyle of humerus and adjacent intermuscular septum together with extensor digitorum
Extensor digiti minimi muscle
*INSERTION: Extensor hood of little finger
Extensor digiti minimi muscle
*INNERVATION: Posterior interosseous (C7, C8)
Extensor digiti minimi muscle
*FUNCTION: extends little finger
Extensor digiti minimi muscle
*ORIGIN: Lateral epicondyle of humerus and posterior border of ulna
Extensor carpi ulnaris
muscle
*INSERTION: Tubercle on the base of the medial side of metacarpal V
Extensor carpi ulnaris
muscle
*INNERVATION: Posterior interosseous (C7, C8)
Extensor carpi ulnaris
muscle
*FUNCTION: Extends and adducts the wrist
Extensor carpi ulnaris
muscle
*ORIGIN: Lateral epicondyle of humerus
Anconeus muscle
*INSERTION: Olecranon and proximal posterior surface of ulna
Anconeus muscle
*INNERVATION: Radial nerve (C6, C7, C8) (via branch to medial head of triceps brachii)
Anconeus muscle
*FUNCTION: Abduction of the ulna in pronation; accessory extensor of elbow joint
Anconeus muscle
Consists of 5 muscles- all of which except for the supinator muscle originate from posterior surface of the radius, ulna, or interosseous membrane and pass into the thumb and index finger
deep layer of posterior forearm compartment
innervated by the posterior interosseous nerve (a continuation of the deep branch of the radial nerve)
deep muscles
has 2 heads- superficial and deep heads
supinator
*ORIGIN: Superficial part- lateral epicondyle of humerus, radial collateral and anular ligaments; deep part- supinator crest
supinator muscle
*INSERTION: Lateral surface of radius superior to the anterior oblique line
supinator muscle
*INNERVATION: Posterior interosseous nerve (branch of radial nerve (C6, C7)
supinator muscle
*FUNCTION: supination
supinator muscle
*ORIGIN: Posterior surfaces of ulna and radius (distal to the attachments of supinator and anconeus), and intervening interosseous membrane
Abductor pollicis longus
muscle
*INSERTION: Lateral side of base of metacarpal I
Abductor pollicis longus
muscle
*INNERVATION: Posterior interosseous nerve (branch of radial nerve (C6, C7)
Abductor pollicis longus
muscle
*FUNCTION: Abducts carpometacarpal joint of thumb; accessory extensor of the thumb
Abductor pollicis longus
muscle
*ORIGIN: Posterior surface of radius and adjacent interosseous membrane
Extensor pollicis brevis
muscle
*INSERTION: Dorsal surface of base of proximal phalanx of thumb
Extensor pollicis brevis
muscle
*INNERVATION: Posterior interosseous nerve (branch of radial nerve (C6, C7)
Extensor pollicis brevis
muscle
*FUNCTION: Extends metacarpophalangeal joint of the thumb; can also extend the carpometacarpal joint of thumb
Extensor pollicis brevis
muscle
*ORIGIN: Posterior surface of ulna (distal to abductor pollicis longus)and the adjacent interosseous membrane
Extensor pollicis longus
muscle
*INSERTION: Dorsal surface of base of proximal phalanx of thumb
Extensor pollicis longus
muscle
*INNERVATION: Posterior interosseous nerve (branch of radial nerve (C6, C7)
Extensor pollicis longus
muscle
*FUNCTION: Extends interphalangeal joint of the thumb; can also extend carpometacarpal and metacarpophalangeal joints of thumb
Extensor pollicis longus
muscle
*ORIGIN: Posterior surface of ulna (distal to abductor pollicis longus)and the adjacent interosseous membrane
Extensor indicis muscle
*INSERTION: Extensor hood of index finger
Extensor indicis muscle
*INNERVATION: Posterior interosseous nerve (branch of radial nerve (C6, C7)
Extensor indicis muscle
*FUNCTION: extends index finger
Extensor indicis muscle
supplied by the radial nerve, posterior and anterior interosseous arteries
posterior compartment of forearm
- nerve of the posterior compartment of forearm
- the deep branch innervates most muscles
radial nerve
becomes the posterior interosseous nerve after emerging into the posterior compartment
deep branch of radial nerve
made up of the wrist (carpus), the metacarpus, and the digits
the hand
fingers form an arcade
normal position
fingers are extended
anatomical position
palmer side of the hand
anterior side
dorsum of the hand
posterior side
how are the movements of the fingers described?
in relation to the long axis of the middle finger
what is the position of the long axis of the thumb in anatomical position?
perpendicular to the rest of the digits
what are the 3 groups of bones in the hand?
- carpals (wrist)
- metacarpels (I to V)
- phalanges (bones of digits)
tend to act as a bony unit
carpals bones and the metacarpals of the index, middle, ring, and little finger
form an arch and along with the flexor retinaculum form the so-called carpal tunnel
carpal bones
what does each metacarpel and phalange have?
has a base, shaft (body), and head
how many phalanges do digits II-V have?
3
how many phalanges does digit I have?
2
a synovial joint between: the distal end of the radius, articular discs of the distal end of the ulna, scaphoid, lunate, triquetrum
wrist joint
form a convex contour which houses the concave surfaces of the radius and articular discs
articular surfaces of the carpals
reinforce the wrist joint and form the capsule
ligaments
the saddle joint of the thumb imparts much more movement than the rest of the digits
Carpometacarpal joints-
provide flexion, extension, abduction, adduction, circumduction, and limited rotation
Metacarpophalangeal joints
reinforced by the palmar, collateral, and deep transverse metacarpal ligaments
Metacarpophalangeal joints
mainly flex and extend and are reinforced by collateral and palmar ligaments
Interphalangeal joints
what do the tendons of flexor digitorum superficialis and profundus and flexor carpi radialis pass through?
the carpal tunnel
what does the median nerve pass through?
carpal tunnel
surrounded by synovial sheaths
all tendons of carpal tunnel except palmaris longus
- formed by deep fascia that is anchored to the skin
- attached to the palmaris longus when present, otherwise it is anchored to the flexor retinaculum
palmaris aponeurosis
connect longitudinal fibers
transverse fibers
a small intrinsic muscle of the hand that deepens the cup of the palm by pulling the skin over the hypothenar eminence, which may improve grip
palmaris brevis
Formed by extensor tendons on the posterolateral side of the wrist
anatomical snuffbox
formed by tendons of abductor pollicis longus and extensor pollicis brevis
lateral side of anatomical snuffbox
formed by tendon of extensor pollicis longus
medial side of anatomical snuffbox
formed by the scaphoid and trapezium bones and tendons of extensor carpi radialis and extensor carpi radialis brevis
floor of anatomical snuffbox
associated with the snuffbox
cephalic vein and radial artery
where do the tendons of flexor digitorum superficialis and profundus go after exiting the carpal tunnel?
cross the palm and enter fibrous sheaths
begin proximally, anterior to the metacarpophalangeal joints
fibrous sheaths
what are fibrous flexor sheaths attached to proximally?
margins of phalanges and palmar ligaments of metacarpophalangeal and interphalangeal joints
prevent bowing of tendons during flexing
fibrous flexor sheaths
pass onto the dorsal side of digits and form extensor hoods or dorsal digital expansions on proximal phalanges
Tendons of extensor digitorum and extensor pollicis longus muscles
attach to free margins of the hoods on each side, providing for delicate hand movements
intrinsic hand muscles
what are the intrinsic muscles of the hand?
- palmaris brevis
- interossei
- adductor pollici
- thenar
- hypothenar
- lumbricals
function to execute precision gripping with fingers and thumb
intrinsic hand muscles
all intrinsic hand muscles are innervated by the deep branch of the ulnar nerve except what?
the 3 thenar and 2 lateral lumbricals
the most dorsal and lie between the metacarpals and adduct, abduct, flex and extend (through extensor hoods) the fingers
Dorsal interossei
anterior to dorsal interossei
Palmar interos
often rudimentary
First palmar interossei
Adduct fingers and through attachment into extensor hoods also flex and extend digits
First palmar interossei
- a large triangular muscle anterior to the plane of the interossei
- 2 heads converge into a tendon that contains a sesamoid bone and attaches to the medial side of base of proximal phalanx of thumb
adductor pollicis
The adductor pollicis is a powerful………?
a powerful adductor of the thumb and opposes the thumb to the fingers
what are the 3 thenar muscles?
- opponens pollicis
- abductor pollicis brevis
- flexor pollicis brevis
what are the thenar muscles innervated by?
median nerve
rotates and flexes metacarpal I
Opponens pollicis
abducts the thumb
Abductor pollicis brevis
flexes the metacarpophalangal joint of thumb
Flexor pollicis brevis
what are the 3 hypothenar muscles?
- opponens digiti minimi
- abductor digiti minimi
- flexor digiti minimi brevis
rotates metcarpal V toward thumb
Opponens digiti minimi
principle abductor of little finger
Abductor digiti minimi
flexes metacarpophalangal joint
Flexor digiti minimi
what are the 4 lumbricals (wormlike)?
1st and 2nd are unipennate, 3rd and 4th are bipennate
- link flexor and extendor tendons by inserting into the extensor hoods
- flex metacarpophalangeal joints while also extending interphalangeal joints
lumbricals
innervated by the deep ulnar nerve
medial 2 lumbricals
innervated by the median nerve
lateral 2 lumbricals
supply the hand with blood
radial and ulnar arties
contributes substantially to the thumb and lateral side of the index finger
radial artery
supply the remaining digits and medial side of the index finger
ulnar artery
gives rise to the superficial palmar arch and the deep palmar branch
ulnar artery
what are the branches of the palmar arch?
palmar digital artery, common palmar digital arteries which are joined by metacarpal arteries from the deep arch to become proper palmar digital arteries
forms the deep palmar arch
radial artery
what does the radial artery give off before penetrating the back of the hand?
gives off the dorsal carpal arch which gives off 3 dorsal metacarpal arteries
what are the branches of the radial artery?
- princeps pollicis
- radialis indicis
- deep palmar arch arteries
follow the same pattern as the arteries in the hand
deep veins
drain into the dorsal venous network on the back of the hand
superficial veins
drain into the lateral and medial side respectively
cephalic and basilic veins
nerves that supply the hand
ulnar, median, and radial nerves
what do the ulnar, median, and radial nerves contribute to?
cutaneous sensation
innervates most intrinsic muscles of the hand
ulnar nerve
mostly motor
deep branch of the ulnar nerve
is mostly sensory
superficial branch of ulnar nerve
most important as it innervates the skin of the thumb, index, middle fingers, and lateral side of the ring finger
median nerve
innervates the thenar muscles
recurrent branch of median nerve
innervate the skin of palm and digits on palmar side
digital nerves
what part of the radial nerve enters the hand?
superficial branch
innervates the skin of the dorsolateral aspect of the palmar side and dorsal side of the hand lateral digits
superficial branch of the radial nerve
