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Flashcards in week 3 Deck (32)
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1
Q

what two groups of back muscles are there?

A
  • intrinsic and extrinsic.
2
Q

what do the extrinsic back muscles do?

A

The extrinsic back muscles include superficial and
intermediate muscles that produce and control limb and respiratory movements, respectively.

3
Q

what do the intrinsic back muscles do?

A
  • The intrinsic (deep)
    back muscles include muscles that specifically act on the vertebral column, producing its movements and
    maintaining posture.
4
Q

what are the superficial extrinsic back muscles?

A

The superficial extrinsic back muscles (trapezius, latissimus dorsi, levator scapulae, and rhomboids) are posterior
axio-appendicular muscles that connect the axial skeleton (vertebral column) with the superior appendicular
skeleton (pectoral girdle and humerus) and produce and control limb movements. Although located in the back
region, for the most part these muscles receive their nerve supply from the anterior rami of cervical nerves and act
on the upper limb. The trapezius receives its motor fibers from a cranial nerve, the spinal accessory nerve (CN XI).

5
Q

what are the intermediate extrinsic back muscles?

A

(serratus posterior) are thin, weak muscles, commonly designated as
superficial respiratory muscles, but are more likely proprioceptive rather than motor in function. The serratus
posterior superior lies deep to the rhomboid muscles, and the serratus posterior inferior lies deep to the
latissimus dorsi. Both serratus muscles are innervated by intercostal nerves.

6
Q

what are the intrinsic back muscles?

A

The intrinsic back muscles (muscles of back proper, deep back muscles) are innervated by the
posterior rami of spinal nerves and act to maintain posture and control movements of the vertebral
column. These muscles, which extend from the pelvis to the cranium, are enclosed by deep fascia,
the thoracolumbar fascia. It extends laterally from the spinous processes and forms a thin
covering over the intrinsic back muscles in the thoracic region and a strong thick covering for
muscles in the lumbar region.

7
Q

what 3 layers do intrinsic back muscles have?

A

The intrinsic back muscles are grouped into superficial, intermediate, and deep layers according
to their relationship to the surface.

8
Q

what are the superficial layer of deep back muscles?

A

The splenius muscles (L. musculi splenii) are thick and flat and lie on the lateral and posterior aspects of the neck, covering the
vertical muscles somewhat like a bandage, which explains their name (L. splenion, bandage). The splenius muscles cover and hold
the deep neck muscles in position.

9
Q

what is the intermediate layer of deep back muscles?

A

The massive erector spinae muscles lie in a “groove” on each side of the vertebral column between the spinous processes centrally
and the angles of the ribs laterally.
The erector spinae are the chief extensors of the vertebral column and are divided into three columns: The iliocostalis forms the
12 lateral column, the longissimus forms the intermediate column, and the spinalis forms the medial column.
Each column is divided regionally into three parts according to the superior attachments (e.g., iliocostalis lumborum, iliocostalis
thoracis, and iliocostalis cervicis).
The common origin of the three erector spinae columns is through a broad tendon that attaches inferiorly to the posterior part of the
iliac crest, the posterior aspect of the sacrum, the sacro-iliac ligaments, and the sacral and inferior lumbar spinous processes.
The erector spinae are often referred to as the “long muscles” of the back. In general, they are dynamic (motion-producing) muscles,
acting bilaterally to extend (straighten) the flexed trunk

10
Q

what is the deepest layer of deep back muscles?

A

Deep to the erector spinae is an obliquely disposed group of much shorter muscles, the transversospinalis muscle group,
consisting of the semispinalis, multifidus, and rotatores. These muscles mainly originate from transverse processes of vertebrae
and pass to spinous processes of more superior vertebrae. They occupy the “gutter” between the transverse and the spinous
processes and are attached to these processes, the laminae between them, and the ligaments linking them together.
The semispinalis is the superficial member of the group. As its name indicates, it arises from approximately half of the vertebral
column. It is divided into three parts according to the superior attachments; semispinalis capitis, semispinalis thoracis, and
semispinalis cervicis. Semispinalis capitis forms the longitudinal bulge in the back of the neck near the median plane.
The multifidus is the middle layer of the group and consists of short, triangular muscular bundles that are thickest in the lumbar region
(Fig. 2.38B).
The rotatores, or rotator muscles, are the deepest of the three layers of transversospinalis muscles and are best developed in the
thoracic region.
The interspinales, intertransversarii, and levatores costarum are minor deep back muscles that are relatively sparse in the
thoracic region. The interspinales and intertransversarii muscles connect spinous and transverse processes, respectively.
The elevators of the ribs represent the posterior intertransversarii muscles of the neck.

11
Q

what is the suboccipital region?

A

The suboccipital region is a muscle “compartment” deep to the superior part of the
posterior cervical region, and deep to the trapezius, sternocleidomastoid, splenius, and
semispinalis muscles. It is a pyramidal space inferior to the external occipital
prominence of the head that includes the posterior aspects of vertebrae C1 and C2.
The four small muscles of the suboccipital region lie deep (anterior) to the semispinalis
capitis muscles and consist of two rectus capitis posterior (major and minor) and two
obliquus muscles. All four muscles are innervated by the posterior ramus of C1, the
suboccipital nerve.

12
Q

what are the anterior muscles of the neck.

A

The anterior neck muscles can be divided into two major groups; superficial and deep.
The superficial group contains the platysma and sternocleidomastoid. The deep
group includes the following muscles:

13
Q

what are the deep anterior muscles of the neck?

A
  1. Longus capitis
  2. Longus coli
  3. Rectus capitis anterior
  4. Rectus capitis lateralis
  5. Anterior Scalene
  6. Middle Scalene
  7. Posterior Scalene
    - all muscles in this group are innervated by the cervical spinal nerves at the corresponding levels.
14
Q

What are the components of the thoracic cage?

A
  • superior thoracic aperture.
  • 1st rib and coastal cartilage.
  • superior border of the manubrium.
  • body of the sternum.
  • xiphisternal joint.
  • infrasternal (subcostal) angle.
  • xiphoid process.
  • inferior thoracic aperature.
  • costal arch.
15
Q

what makes up the superior thoracic aperture?

A
  • anteriorly is the superior border of the manubrium.
  • posteriorly and laterally sides are the first rib and costal cartilage.
16
Q

what makes up the inferior thoracic aperture?

A
  • 12th thoracic vertebrae, costal arch and infrasternal (subcostal) angle.
17
Q

what are intercostal spaces?

A
  • 11 intercostal spaces filled with the intercostal muscles, nerves and veins.
18
Q

what are the intercostal muscles?

A
  • 3 flat layers, external, internal and innermost.
19
Q

what are the attachments for the diaphragm?

A

-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.

20
Q

what are the three main foramina of the diaphragm?

A

Aortic hiatus or opening (TXII level), esophageal hiatus
or opening (TX Level) and caval opening (TVIII level)

21
Q

what is the nerve supply of the diaphragm?

A

R. & L. phrenic nerves (C3,4,5)

22
Q

what does the diaphragm do?

A

-depresses domes (i.e. move inferiorly) therefore Increases the volume of the thoracic
cavity
- ↑ Volume, ↓ pressure, therefore it is the major muscle of inspiration

23
Q

what are the movements of the thoracic wall?

A
  1. range of movement is smaller superiorly and larger anteriorly.
  2. bucket-handle movement.–> elevation of the lateral shaft of the rib.
  3. superior and anterior movement of the sternum, pump handle.
24
Q

what is the pectoral region?

A

Is external to the anterior thoracic wall and anchors the
upper limb to the trunk.
- Mammary glands are modified sweat glands in the
superficial fascia in this region. The nipple is surrounded
by a circular pigmented area of skin termed areol

25
Q

what is the arterial supply of the breast?

A

Axillary A. (mainly by its lateral thoracic
branch)
- Internal thoracic A.
- 2nd to the 4th intercostals arteries.

26
Q

what is the venous drainage of the breast?

A

-Axillary, internal thoracic & intercostal
veins.

27
Q

what is the innervation of the breast?

A

2nd to 6th intercostal nerves.
- Nipple is innervated by the 4th intercostal
N

28
Q

what is the lymphatic drainage of the breast?

A

75% into axillary nodes.
- The rest, mainly into the parasternal lymph
nodes.

29
Q

What is the arterial supply of the thoracic wall?

A

Posterior intercostal
arteries. Mainly branches of
the thoracic aorta
- Anterior intercostal
arteries. Branches of the
internal thoracic artery
directly or indirectly

30
Q

What is the venous drainage of the thoracic wall?

A

-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.

31
Q

what is the nerve supply of the thoracic wall?

A

-Is mainly done by the
anterior rami of the
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.
- thoracoabdominal nerves (T7-T11).
- subcostal nerve (T12).
- iliohypogastric nerve (L1).
- Ilioinguinal nerve (L1).

32
Q

what are the vessels of the anterolateral abdominal wall?

A
  • internal thoracic artery.
  • musculophrenic artery.
  • superior epigastric artery.
  • 10th posterior intercostal artery.
  • 11th posterior intercostal artery.
  • internal oblique
    -subcostal.
  • transversus abdominis.
  • inferior epigastric artery.
  • deep circumflex iliac artery.
  • superficial epigastric artery.
    -superficial circumflex iliac artery.
  • external iliac artery.
    -femoral artery.