Week 3 Flashcards
what do extrinsic back muscles do
control limb and respiratory movements
name the two major groups of muscles in the back
the extrinsic and intrinsic
what do the intrinsic (deep) muscles do
act on the vertebral column, producing its movements and maintaining posture
both serratus muscles are innervated by _________ nerves running within the ribcage
intrinsic back muscles are innervated by
posterior rami of spinal nerves
intrinsic back muscles act to
maintain posture and control movements of the vertebral column
The _______ muscles cover and hold the deep neck muscles in position.
splenius
what is the common origin of the three erector spinae
a broad tendon that attaches inferiorly to the posterior part of the lilac crest, the posterior aspect of the sacrum, the sacro-iliac ligaments, and the sacral and inferior lumbar spinous processes.
the primary action of semispinalis
extension of the head, cervical spine and thoracic spine
contralateral rotation
where is the multifidus thickest?
in the lumbar region
what is the action of the multifidus?
stabilization of the vertebral column
where is the rotatores best developed?
in the thoracic region
what is the primary action of the rotatores?
stabilization of the vertebral column; proprioception of the vertebral column and may assist in small oratory movements in the thoracic spine
segmental muscles of the back are relatively sparse in which region?
the thoracic region
suboccipital muscles are innervated by
the posterior ramus of C1, the suboccipital nerve
innervation of Sternocleidomastoid (SCM).
cranial nerve 11 - spinal accessory nerve
innervation of platysma
cranial nerve 7 - facial nerve
what are the three main foramina in the diaphragm?
Aortic hiatus or opening (TXII level), esophageal hiatus or opening (TX Level) and caval opening (TVIII level)
what is the nerve supply of the diaphragm?
R. & L. phrenic nerves (C3,4,5)
action of the diaphragm
depress dome (moves inferiorly) therefore increasing the volume of the thoracic cavity
- volume increases and pressure decreases, therefore it is the major muscle of inspiration
diaphragm attachments
xiphoid process, costal margin, end of ribs 11 and 12, lumbar vertebra (LI - LIII).
- Muscle fibers converge from the peripheral attachments of the muscle to join to the central tendon.
which muscles make up the superficial layer of extrinsic back muscles
trapezius, latissimus dorsi, levator scapulae, and rhomboids
How are the extrinsic back muscles innervated?
their nerve supply from the anterior rami of cervical nerves and act on the upper limb.
how is the trapezius intervated?
motor fibers from a cranial nerve, the spinal accessory nerve (CN XI). (11)
what does serratus mean
fan-shaped muscle attachment (multi-attachment)
- creates a saw-tooth appearance, resembles the serrated edge of a knife
Serratus Posterior Superior
elevates ribs 2-5
- allows lungs to inflate
lies deep into the rhomboid muscle
- has a proprioceptive function (spatial awareness)
- innervated by intercostal nerves running within the ribcage
Serratus Posterior Superior and Inferior
Serratus Posterior Inferior
depresses ribs 10-12
lies deep to the latissimus dorsi
- has a proprioceptive function (spatial awareness)
Intermediate extrinsic back muscles
serratus posterior superior
serratus posterior inferior
Describe the Intermediate extrinsic back muscles
- thin, weak, muscles commonly designated as superficial respiratory muscles
- move the upper limbs and ribcage
what are the three groupings of intrinsic back muscles
- superficial (spinotransverse)
- intermediate (sacropinalis)
- deep (transversospinalis group)
what muscles make up the spinotransverse group of intrinsic back muscles?
- splenius capitis
- splenius cervicics
what muscles make up the sacrospinalis group of intrinsic back muscles?
- erector spinae (spinalis, longissimus, iliocostalis)
what muscles make up the transversospinalis group of intrinsic back muscles?
- semispinalis
- multifidus
- rotatores
large, roughly diamond-shaped area of connective tissue constituted by the thoracic and lumbar parts of the deep fascia enclosing the intrinsic back muscles
thoracolumbar fascia
splenius capitis position and action
starts on SP to head
- extend head and neck, ipsilateral rotation
Describe splenius capitis and Splenius Cervicis
are thick and flat and lie on the lateral and posterior aspects of the neck, covering the vertical muscles somewhat like a bandage
Splenius Cervicis position and action
start on SP to TVP of the cervical spine
- extend head and neck
what movements do splenius capitis and splenius cervicis permit
extension, lateral flexion and ipsilateral (same side) rotation
Iliocostalis is part of which group
part of the sacrospinalis group
Iliocostalis description
Fibers run superiorly and slightly laterally attaching to angles of ribs and cervical TVP’s
forms the lateral column
Longissimus part of which group
part of the sacrospinalis group
Longissimus description
froms the intermediate column T
Fibers run superiorly attaching to TVP’s in thoracic and cervical regions and the mastoid process of the occiput
Spinalis group and description
part of the sacrospinalis group
forms the medial column
Fibers run superiorly within the laminar groove attaching to SP’s in thoracic and cervical regions
what movement do the sacrospinalis group do?
flexion, extension, left and right bending (lateral flexion)
- don’t need to be worked out - they are ALWAYS working
Semispinalis parts
divided into three parts according to the superior attachments:
Semispinalis capitis
Semispinalis cervicis
Semispinalis thoarcis
Semispinalis action
primary actions
bilateral: an extension of the head, cervical spine and thoracic spine
unilateral: contralateral (helps on the opposite ride) rotation
Multifidus and primary action
part of the transversospinalis group (deepest part of intrinsic back muscles)
thickest in the lumbar region
primary action: stabilization of vertebral column (mainly in lumbar region)
Rotatores grouping
part of transversospinalis group (deepest part of intrinsic back muscles)
best developed in the thoracic region
Rotatores primary action
- important for providing proprioception from the posterior ribcage to the brain
primary action: stabilization of vertebral column, which may assist in small rotatory movements in the thoracic spine
what is the general attachment for semispinalis group?
TVP - SP
what is the segmental muscle of the back?
the interspinales (SP-SP) and intertransversarii muscle (TVP-TVP)
- they connect spinous and transverse processes
interspinales action
bilateral action: aid in extension
unilateral action: segmental rotation
Intertransversarii action
stabilization and lateral flexion
Levatores Costarum attachment and action
from rib to TVP
- assist with respiration (inhalation) in elevation of ribs; lateral flexion of column
Suboccipital Region Muscles
made up of four muscles
- two rectus capitis posterior (major and minor) and
- two obliquus
primary action of suboccipital region
extension of atlanto-occipital joint
rotation of atlanto-axial joint
what muscles are in the superficial group of the anterior neck
- platysma
- sternocleidomastoid
platysma origin and insertion
ori: fascia over deltoid and pectoralis major muscle
Ins: mandible and skin of the lower face
platysma function
- depresses and draws lower lip inferiorly
- depresses mandible @ TMJ
platysma function inverted by
nerve 7
Sternocleidomastoid origin and insertion
origin: sternum and medial 1/3 clavicle
insertion: the mastoid process of the temporal bone
- lateral 1/2 of the superior nuchal line of the occipital bone
Sternocleidomastoid unilateral contraction
unilateral contraction: lateral flexion of the head and neck
contralateral rotation of the head and neck
Sternocleidomastoid bilateral contraction
bilateral contraction: Ext. of head & and upper neck
Flex. of the lower neck
Elevation of sternum and clavicle (during forced inhalation)
Sternocleidomastoid innveration
N: Cranial never. 11 (Spinal accessory nerve)
the deep group of muscles in the anterior neck
- longus capitis
- longus coli
- rectus capitis anterior
- rectus capitis lateralis
- anterior scalene
- middle scalene
- posterior scalene
which pair of muscles in the anterior neck move C1 and the occiput
- rectus capitis anterior - flexion of C1
- rectus capitis lateralis - more of a stabilizer muscle
how many Scalenes do we have
we have 3 of them
- anterior
- middle - first fib during inspiration
- posterior - 2nd rib during inspiration
allow lateral flexion to the same side
external intercostal muscles primary action
moves rib superiorly during inspiration
external intercostal muscles ins. org.
O: inferior border of rib above
I: superior border of the rib below
internal intercostal muscle action
moves ribs inferiorly during forceful expiration (not active during standard exhalation)
internal intercostal muscle ins. org.
O: superior border of the rib below
I: inferior border of rib above
diaphragm muscle action
A large, flat muscle at the bottom of the chest cavity - depresses domes; and moves inferiorly to increase the volume of the thoracic cavity
- muscle fibres converge from the peripheral attachments of the muscle to join to the central tendon
diaphragm muscle innervation
N: phrenic nerves (C3,4,5)
what are the diaphragm attachments
xiphoid process, costal margin, end of ribs 11 and 12, lumbar vertebra (LI - LIII).
function of diaphragm
contacts to enlarge the thoracic cavity and reduce the intrathoracic pressure
movement of the ribs and thoracic cage that occurs as respiratory muscles contract and thoracic volume changes
bucket handle movement
Elevation of the Sternal End of the Rib, increasing the anterior to posterior diameter of the Thoracic cavity
pump handle movement
external to anterior thoracic wall; anchors upper limb to trunk
pectoral region
are modified sweat glands in the superfascia that produce milk
mammary glands
surrounding the nipple, a circular pigmented area of the skin
Aerola
Arterial supply of the breast
- Axillary Artery (mainly by its lateral thoracic branch)
- Internal thoracic Artery
- 2nd to the 4th intercostals arteries.
Venous drainage of the breast:
- Axillary, internal thoracic & intercostal veins.
Innervation of the breast:
2nd to 6th intercostal nerves.
Nipple is innervated by the 4th intercostal Nerve
suspensory ligaments of the mammary gland
thickenings of superficial fascia that attach the breast to the deep fascia
Lymphatic drainage of the breast:
75% into axillary lymph nodes.
- The rest, mainly into the parasternal (mid-on-the sternum) lymph nodes.
Arterial supply of the thoracic wall
- Posterior intercostal arteries. Mainly branches of the thoracic aorta
- Anterior intercostal arteries. Branches of the internal thoracic artery directly or indirectly
Venous drainage of the thoracic wall
- Posterior intercostal veins: mainly drain on the R. side into azygos vein and on the L. side into the hemiazygos or accessory hemiazygos.
- Anterior intercostal veins: drain (directly or indirectly) into internal thoracic veins which in turn drain into R. & L. brachiocephalic veins.
Nerve supply of the thoracic wall
Is mainly done by the anterior rami of the upper thoracic spinal nerves [called intercostal Nerves (T1 - T11)
The Ant. ramus of the spinal N. T12 (The subcostal N) is under rib #12.
- They supply the intercostal muscles, skin of the chest wall and parietal pleura.
- The lower intercostal nerves supply the skin & muscles and parietal peritoneum of the abdominal wall.
what is located at T4
the nipple
what is located at T5/T6
the xiphoid process
Nerve cells that conduct impulses away from the central nervous system
- create movement
efferent neurons
Nerve cells that carry impulses towards the central nervous system
afferent neurons
Nerve supply of anterior abdominal wall
the lower intercostal nerves T7-T11 and T12
Vessels of Anterolateral Abdominal wall
Superior epigastric artery, which is a direct continuation of the internal thoracic artery
· Inferior epigastric; branch of the external iliac artery
· Branches of intercostal arteries
· Venous drainage of the abdominal wall is accomplished through veins that run parallel to the above mentioned arteries.
what are the functions of the extrinsic back muslces
- produce and control limb movements
main action of longus colli
flexes neck with roation to opposite side if acting unilaterally
Main action of longus capitis
flex head
main action of rectus capitis anterior
flex head
main action of anterior scalene
flexes neck laterally
elevates 1st rib during forced inspiration
main action of rectus capitis lateralis
flexes head and helps stabilize it
main action of middle scalene
Flexes neck laterally; elevates 1st rib during forced inspiration
main action of posterior scalene
Flexes neck laterally; elevates 2nd rib during forced inspiration
which muscles produce flexion of cervical joints
bilateral action of longus coli, scalene and sternocleidomastoid
which muscles produce extension of cervical joints
sternocleidomastoid
trapezuis
deep neck muscles
- semispinalis cervicics and iliocostalsis cervicic
- splenius cervicitis and levator scapulae
- splenius capitis
- multifidus
- longissimus capitis
- semispinalisis capitis
which muscles produce lateral bending of cervical joints
unilateral action of
- iliocstalisis cervicics
- longissimuis capitis and cervicicis
- splenius capitisi and cervivics
- intertransversaii and scalenes
- sternocleidomastoid
which muscles produce rotation of cervical joints
unilateral action of
- rotatores
- semispinalisis capitis and cervicics
- multifidus
- splenius capitis
which muscles produce flexion of Thoracic and Lumbar joints
bilateral action of
- rectus abdominis
- psosas major
- gavity
which muscles produce extension of Thoracic and Lumbar joints
bilateral action of
- erector spinae
- multitdifus
- semispinalisis throacis
which muscles produce lateral bending of Thoracic and Lumbar joints
which muscles produce rotation of Thoracic and Lumbar joints
