Download The axilla

The axilla
*The axilla:armpit(elle lonha a59'r),it is pyramidal-shaped , it lies in the
upper part of the arm on the side of the chest(y3ne ayya wa7d b7o6
edoh bla2eha 3la jnb elchest).
*or it lies between thoracic wall medially and humerus(bicipital
groove)laterally, between bicipital groove & the chest wall.
*Pyramidal mean has apex & base:
Base= stretching skin between anterior,posterior,medial and lateral
walls.
Apex= clavicle is anterior to apex, apex are triangle connect the axilla
with the root of the neck, which called costoscapular triangle.
*boundaries:
Anteriorly=clavicle
Posteriorly=superior border of scapula
Medially=the first costal cartilage or the first rib.
Importance of apex: most of vessels and nerves which descending from
the root of the neck to the upper limb are transmitted through the apex
until reach axilla and become the content of axilla.
*the upper end of the axilla or the apex is directed to the root of the
neck bounded in front of the clavicle, behind upper border of scapula,
medially the outer border of the first rib.
----------------------------------*Look to the image which shows:
In the root of the neck found anterior scalene & middle scalene muscles
or scalenus anterior & scalenus medius muscles.this 2 muscle are
important because the root of brachial plexus it origin between these 2
muscle.
So, the root of brachial plexus lies between scalenus anterior & scalenus
muscles in the root of the neck.( brachial plexus =lonha a9fr).
---------------------------------*Next image = boundaries of the axilla:
Medially: the upper 4or5 ribs.which give attachment to serratus anterior
muscle.
Any muscle, we have to its origin,insertion,action and nerve supply.
* serratus anterior muscle:
Nerve supply: long thoracic nerve
Origin: from the upper 8 ribs.
Insertion: medial border of scapula (ventrally)
Action: with trapizus to rotation of scapula to put your hand of the
head>90grade.
----------------*Serratus medially but laterally bicipital groove(long head of biceps) &
coraco-brachialis muscle(med).
Anterior = pectoralis major and pectoralis minor(deep to it).
//anterior border can be catched by your finger//
*lower part or fold = lower edge of pectoralis major.
*posteriorly: subscapularis,teres major and latissmus dorsi muscles(we
have to read it carefully).
----------------Subscapularis muscle :
Origin:subscapular fossa
Insertion: lesser tubercle
Nerve supply:upper & lower subscapular nerve.
Action: because it lies posteriorly & its insertion anteriorly make medial
rotation and adduction of the arm.
----------------Teres major muscle:
Origin: lateral border of scapula
Insertion: medial lip of bicipital groove
Nerve supply: nerve from axillary nerve
Action: the same of subscapularis muscle because it is from post. To ant.
*(doctor 5rb6 7ka "the same of teres major")
----------------Latissmus dorsi: it is a wide muscle
Origin : from lumbar fascia of lower 6 ribs & inferior angle of scapula .
Insertion : floor of bicipital groove
Nerve supply : nerve to latissmus dorsi or thoracodorsal nerve .
Action: it's the muscle of climbing , extension , adduction & medial
rotation . it's raising the trunk upward .
In the wall of axilla ( deep to pectoralis major ) there are clavipectoral
fascia which encircle pectoralis minor.
-axillary artery is a content of axilla.
Serratus anterior:
Origin: upper 8 ribs.
Insertion: medial border of scapula(ventrally)
Because on dorsally attached to rhomboid major,minor and levator
scapula.
-----------------
-refer to image in gray's\ it shows axillary vessels (artery & vein) &
brachial plexus & surrounded by sheath which called axillary sheath and
expanded from the deep fascia of the root of the neck.
Clavipectoral fascia(cutting of pectoralis major.
-medial pectoral nerve penetrate pectoralis minor and supply it. But
pectoralis major is supplied by medial and lateral pectoral nerve.
-clavipectoral fascia is a strong sheath.
Above: clavicle surrounding subclavius musclesplit to anterior &
posterior.
Below: it splits to cover pectoralis minor.
----------------Pectoralis minor:
Origin:3,4,5ribs
Insertion: coracoids process
Nerve supply:medial pectoralis nerve
-----------------continues downwards as suspensory ligament of the axilla joining the
floor of armpit.
-the structure travel between the axilla and the anterior wall of
clavipectoral fascia:
Attachment: medially: 1,2 costal cartilage//laterally :coracoid
process(look acromion free).
-importance structure pass between subclavius & pectoralis minor,
include:
Some structure piercing clavipectoral fascia above pectoralis minor:
4structure: cephalic vein, lateral pectoral nerve(to pectoralis
major),thoracoacromial artery;branch from axillary artery and lymphatic
vessels.#Q#
-importance of clavipectoral fascia; protection to the underneath
structure( deep to it).
----------------Content of Axilla:
1-axillary vessels(axillary artery & axillary vein);artery gives branches but
vein has tributaries.
-axillary a. comes from subclavian a.
-subclavian a. in the left side is branch from the arch of the aorta. But
right side from brachio-cephalic a.
-subclavian a. at the 1st rib is continues as axillary a. & inter the axilla and
considered as content of the axilla.
-always artery opposite vein.
2-tributaries from upper limb to axillary vein and end as subclavian v.
-subclavian v. join with internal jugular v. from the neck to form
brachiocephalic v. on right and left and join each other to become
superior vena cava(S.V.C).
3-lymphatic vessels & lymph nodes as groups(trunk down to umbilicus).
4-brachial plexus nerve supply to upper limb.
5-some structure as fat.
*cords of brachial plexus (root,trunk,divison,cord) supply the upper limb.
*to understand brachial plexus, you have to study nervous system.
THE NERVOUS SYSTEM
1-central nervous system(brain & spinal cord)
2-preipheral nervous system:
31pairs frome spinal nerves (Rt,Lt) from spinal cors to
peripheral(upper & lower limbs).
12 pairs of cranial nerves which origin from brain stem from foramen
to head & neck.
autonomic nervous system=involuntary system(sympathetic &
parasympathetic).
-they supply the viscera,gland and smooth muscle.
-nerve: bundles of nerve fibers(axon)supported by areolar tissue.
-spinal cord begin from foramen magnum as continues to medulla
oblongata and end at disc between(L1,L2) and continues as nerve fibers.
-spinal cord before nerve fibers has white & gray matter.
-section in spinal cord shows central canal,gray matter(H-shaped) and
white matter.
-white matter is an axon(ascending & descending fibers)transmit
impulse.
-gray matter contain nerve cells and has anterior and posterior horns.
-ant. Horn has motor nerve cell\\post. Horn has sensory\\lateral horn
has sympathetic nuclei.
-there are ventral & dorsal roots.
-ventral=motor fibers exit from spinal cord.
-dorsal=sensory fibersinter to spinal cord.
-dorsal root has dorsal root ganglion.
*ganglion=group of nerve cells have the same structure & function.
-dorsal+ventral horns=spinal nerves.
 spinal cord = 31 segments =every segment gives pair of spinal nervs.
-spinal cord is mixed because contain sensory,motor and sympathetic
fibers.
-but parasympathetic related to cranial nerves and S2,3,4.
-spinal cord segments: 8pairs cervical segments=8 pairs of spinal nerves
…but there are 7 vertebrae.
-thoracic=12\\lumbar=5\\sacral=5\\coccygeal=1.
spinal cord:posterior and anterior ramus
-post. Ramus=to vertebral Colman =sensory to skin & motor to muscles
of back.
-ant. Ramus=it is longer than post.=sensory to skin of the body to
midline & motor to ant. Part & limbs.
-ant. Root consist of nerve fibers carrying impulse(motor) from
central(efferent)skeletal muscles and some branch sensory.
-post. Root to central nervous system(sensory from skin)(afferent).
-it is sensory 4 touch,pain ,temperature and vibration in joints.
-its cell body founded in posterior root of the post. Ganglion.
-ventral from ant. Horn.
-post.>back>sensory & motor.
-cutanuse on ant. & lat.
-spinal cord ends as cadua equnia=nerve fibers.
lumber puncture:in meningitis take a biopsy of CSF between L3,L4 OR
L4,L5.
-patient set in form knee enclose to chest.
-enter the needle to reach subarachnoid space under arachnoid matter.
-it's taken between L3,L4 to be away from spinal cord gray matter.
-needle dose not effect on nerve fibers under spinal cord.
-coccyx as one piece, so we can not take lumber puncture there.
-brachial plexus : It is cervical spinal nerves (anterior rami)
-there are lumbosacral plexus(lower limb).
-brachial plexus is found in the root of the neck.
----segmental innervations of the muscle & reflex mechanism:
-Ex:when hit tendon of quadriceps muscle>>leg extension.
-it is reflex from patellar tendon to sensory nerve to spinal cord to ant.
Gray horn to motor nerve and to quadriceps muscle>>contraction and
leg extension.
-if any thing cuts circle, it will not occur knee jerk or reflex or
contraction.and the muscle will paralysis & atrophy.
*autonomic nervous system has sympathetic and parasym.
-parasym. Distributed by cranial nerves 3,7,9,10+sacral spinal nerves
S2,3,4.
-symp. Comes from spinal cord lat. Horn>thoracic segment+L1,L2+S.
SOMATIC & AUTONOMIC:
*Somatic:sensory(skin)>dorsal root ganglion>post.
Horn>interneuron>ventral horn>ventral root>spinal nerves>ant. Ramus>
to the muscle > contraction.
*autonomic:lat. Gray horn>ventral root>spinal nerves>symp. Chain or
collateral ganglion>relay(synape)(pre-post ganglionic).
-Number of preganglionic are 14=white neurons=(all thoracic+L1,L2)
-postganglionic=gray matter=gray ramus=in all spinal nerves = 31.
-symp.>blood vessels>hypertension>tachycardia.
-parasymp.> secretomotor of glands.
BRACHIAL PLEXUS
Has origin from root C5,6,7,8,T1 …..supplementary C4,L2
-ant. Primary ramus of cervical spinal nerves.
rootstrunks(superior ,Middle and inferior)or (upper, middle and
lower)
-sup. C5,6 \\ middle C7 \\ inf. C8,T1.
every trunk divide to divisions(ant. & post.)behind the clavicle in post.
Triangle of the neck.
roots between scalenus anterior & scalenus medius muscles.
-division makes 3 cords(medial, lateral and posterior).which are content
of axilla.
-division upper trunk & middle >>lateral cord.
-ant. dividion of lower trunk>>medial cord.
-all of the post. Divisions>>posterior cord.
*pectoralis minor separate axillary a. into 3 parts.
*subscapular nerve from upper trunk.
*n. to subclavius from upper trunk.
*long thoracic n. to serratus ant. From roots 5,6,7 ant. Ramus
*upper trunk+5,6>>root+dorsal scapular n. >>rhomboids & levator
scapula.
*suprascapular n.>> to supraspinatus +infraspinatus.
Branches of cords:
Lateral cord: 3:lateral pectoral n. \ musculocutanous n. \ lateral root of
-median n.
-medial cord: medial cutanous n. ,med. root of median n. ,med. root of
ulnar n.
-posterior cord:radial n., axillary n., n. to latissimus dorsi and upper&
lower subscapular nerves.