Muscles Back and Upper limb Flashcards
extrinsic muscles innervated by ____ of spinal nerves or CNx vagus
anterioir rami of spinal nerves
intrinsic muscles true back muscles innverated by _____
posterior rami of spinal nerves
origin on ligamentum nuchae and vertebrae (Cl -txll) inserts on scapula and clavicle
trapezies
what is latissimus dorsi
large, flat triangular muscle orgin in lower spine , insertion on humerous anteriorly
trapeziues is innervated by
accessory nerve CN XI and C3&$
Extension, Adduction & Medial Rotation of
arm (swimming butterfly)
* Innervated by nerve of Brachial Plexus
latissimus dorsi
superficial back muscles (deep extrinsic)
Levator scapulae – vertebrae to
scapula - elevates scapula
* Rhomboid minor and rhomboid
major pull the scapula toward the
vertebral column
* Innervated by nerve of Brachial
Plexus
list some qualities of intermediate back muscles
Sometimes referred to as
Respiratory Group
* Serratus posterior superior –elevates ribs II-V
* Serratus posterior inferior –depresses ribs IX-XII
* Innervated by anterior rami of
thoracic nerves (via intercostal
nerves
whats largest group of intrinsic back muscles
erector spinae
Primary extensors of the vertebral
column and head
* Innervated by dorsal rami of spinal
nerves
Thoracolumbar fascia
deeper deep back muscles can be known as
Transversospinales muscles
crossing between
four and six vertebrae from origin
to point of attachment (thoracic
& cervical)
semispinalis
spanning between
two and four vertebrae (most
prominent in lumbar)
multifidus
throughout, crossing
two vertebrae (long rotators) or
one (short rotators)
rotatores
whats innervated by dorsal rami of spinal nerves
Semispinalis - crossing between
four and six vertebrae from origin
to point of attachment (thoracic
& cervical)
* Multifidus - spanning between
two and four vertebrae (most
prominent in lumbar)
* Rotatores – throughout, crossing
two vertebrae (long rotators) or
one (short rotators)
Symptoms = drooping of the shoulder, inability to raise the arm above the
head, or weakness in shrug the shoulder against resistance
weakness in trapezius -injury of accessory nerve CNXI
Symptoms = problems pulling the body upward while climbing or doing a
pull-up.
Weakness in latissimus dorsi - injury to the thoracodorsal nerve
(branch of Brachial nerves)
Symptoms = a lateral shift in the position of the scapula on the affected side
– (antagonistic muscles pulling laterally).
An injury to the dorsal scapular nerve (branch of Brachial nerves),
which innervates the rhomboids
Origin on scapula & clavicle, inserts on deltoid tuberosity of humerus. Arm
abduction (beyond 15 degrees)
deltoid
Origin on scapula, insert on humerus and provide support for the
glenohumeral joint - innervated by Brachial plexus nerves
rotator cuff muscles
ABducts arm first 15 degrees (synergist)
supraspinatus
lateral rotation of arm
teres minor
lateral rotation of arm
infraspinatus
medial rotation of arm
subscapularis
The ____ is a pyramidal area formed by
muscles and bones of the shoulder and thoracic wall.
All major structures pass through
axilla
triangularly shaped depression
anterior to the elbow joint. The brachial artery &
median nerve pass through
cubital fossa
gateway to the hand. Its
posterior, lateral, and medial walls form an arch of small
carpal bones. A connective tissue band, the flexor
retinaculum, forms the anterior wall of the tunnel. The median nerve passes through.
Carpal tunnel
whats an important area
that passes structures from the neck to the upper extremity
* Contents:
* Axillary artery and vein
* Brachial plexus
* Lymphatics and lymph nodes
* Axillary tail of breast
armpit axilla
Complex collection of nerves from spinal cord traveling through neck and
axilla, innervates muscles and skin of upper limb & shoulder
* Comprised of anterior rami of cervical spinal nerves C5-T1
brachial plexus
arm muscles
anterior
biceps brachii flexor compartment innervate what
musculocutaneous nerve
posterior muscles triceps brachii extensor compartment innervate what
radial nerve
2 heads, origin at
scapula and inserts on radius
* powerful flexor of forearm at elbow
(load bearing), supinator when flexed
and flexes glenohumeral joint
* Innervated by Musculocutaneous nerve
biceps brachii
coracoid process of
scapula to medial side of humerus –
flexes at shoulder & adducts arm
coracobrachialis
- Innervated by Musculocutaneous
nerve
deep to biceps brachii,
origin on humerus, inserts on tuberosity of ulna. Flexes elbow
* Innervated by Musculocutaneous
nerve
brachialis
think posterior compartment of the arm
Triceps brachii – 3 heads – extends forearm – innervated by radial nerve
* The long head originates from scapula.
* The medial head originates from posterior surface of humerus
* The lateral head originates on humerus
* All insert on olecranon of Ulna
Damage to the _____ of brachial
plexus occurs when shoulder is forced down
while your neck stretches up and away from
the injured shoulder.
upper nerves
- The ___ are more likely to be injured when your arm is forced above your
head
lower nerves
Depression anterior to the elbow joint
* Contents:
* Tendon of biceps muscle
* Median nerve
* Brachial artery
* Superficial veins used for
venipuncture pass superficially
cubital fossa
Biceps brachii – anterior
compartment of arm
Supinator - posterior compartment
of the forearm
Pronator teres and pronator
quadratus - anterior compartment
of the forearm
– origin at humerus,
powerful flexor and adductor of the wrist -
innervated by Ulnar nerve
flexor carpi ulnaris
Flexor & abductor of
wrist Median nerve - tendon can be easily
palpated
flexor carpi radialis
ANTERIOR compartment of forearm
2 heads, Median
nerve
Forms four tendons, which pass through carpal tunnel
of the wrist and into the four fingers
Flexes metacarpophalangeal joint and proximal
interphalangeal joint of each finger and flexes wrist
joint
flexor digitorum superficials
Palmaris longus – Median nerve - absent in
about 15% of the population
Pronator teres - Median nerve - rotates the
radius over the ulna during pronation
think deep layer flexors
anterior compartment of forearm
-gives rise
to four tendons, which pass through the
carpal tunnel into the four distal
phalanges – innervated by median & ulnar
flexor digitorum profundus
powerful muscle
and forms a single large tendon attaches
at distal phalanx of thumb
flexor pollicis longus
pulls the distal end
of the radius anteriorly over the ulna
during pronation
pronator quadratus
deep posterior compartment of forearm
extensor pollicis longus and brevis
Extensor carpi radialis longus & brevis -
Extensors and abductors of the wrist
* Extensor carpi ulnaris - Wrist extensor and
adductor
- Extensor digitorum - Extensors of digits 2-5
- Brachioradialis - Crosses over lateral elbow
and is an accessory flexor of the elbow
- Muscles that move the hand but muscle
bellies lie in the forearm and tendons extend
to the hand - Involved in power grip
extrinsic muscles
- Muscles that move the hand and whose
bellies lie in the hand - Involved in fine movement (precision grip)
- Innervated by ulnar and median nerves
- Thenar muscles (median nerve)
- Most intrinsic muscles by ulnar nerve
intrinsic muscles
