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1-موضوعات
عامة
2-أشعارى
3-مختارات شعرية و قصصية
4-مقالات أدبية
5-مقالات تاريخية و سياسية
6-شخصيات
7-إسلاميات
8-عروض الكتب
9-القسم الطبى
10-طب الأسنان
11-مدوناتى الخاصة
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The Neck
Like other regions of the body, the neck has a central bony skeletal
core upon which other structures attach or are related. The bones of
the neck consist of the base of the skull and the 7 cervical
vertebrae.
If we take a look at the base of the skull, the major parts that are
related to the upper neck are the:
- Foramen magnum
- Occipital condyle (articulates with the superior process of the
atlas.
- External occipital protuberance
- Mastoid process
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Below
the base of the skull, you will find the vertebral column. The top
vertebrae (7 cervical) provide support for the neck structures. You will
also note that these vertebrae allow passage of an important arterial
supply to the brain and brain stem, the vertebral artery. |
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The first cervical vertebra is the atlas and is considered an atypical
cervical vertebra because it has no body or spinous process. It
articulates with the occipital condyles of the skull above it and with the
superior articular processes of the axis below it. It also articulates
with the dens of the axis below. If viewed from above, you can identify
the following parts of the atlas:
- Anterior arch
- Anterior tubercle
- Superior articular process (articulate with the occipital condyle of
the skull)
- Foramen transversarium
- Transverse process
- Posterior arch
- Posterior tubercle
- Vertebral canal (continuous with the foramen magnum at the base of
the skull). The brain stem continues inferiorly as the spinal cord at
the margin of the foramen magnum.
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The axis is the second cervical vertebra. This vertebral is also called an
atypical vertebra because it has an upward projection called the dens that
articulates with the inner aspect of the anterior arch of the atlas just
posterior to the anterior tubercle. Some of the identifiable parts are
the:
- dens
- body
- superior articular process
- transverse process with its vertebral foramen
- pedicle
- lamina
- bifid spine
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The 3rd, 4th, 5th, and 6th cervical vertebrae are known as the typical
cervical vertebrae because they all have the same characteristics and
except for the foramen for the vertebral artery similar to other typical
vertebrae of the spinal cord. These characteristics are:
- body
- pedicle
- foramen for vertebral artery
- superior articular process
- lamina
- spinous process (bifid in case of cervical vertebrae)
- vertebral canal
- transverse process (consists of a groove that carries a cervical
spinal nerve and, of course the foramen for the vertebral artery)
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The 7th cervical vertebra starts to pick up characteristics of the upper
thoracic vertebrae and may even produce a cervical rib, which can cause
pathological problems related to the brachial plexus.
It has the same characterists as other typical cervical vertebra except
that there is no foramen for the vertebral artery and it may not have a
bifid spinous process. After the vertebral artery arises from the
subclavian artery, it enters the transverse foramen of the 6th cervical
vertebra bypassing the 7th.
The spinous process of the 7 cervical vertebra is longer than those of
the other cervical vertebrae and is not buried under the ligamentum
nuchae of the neck. Therefore, it is easy to see and to palpate and is
called the vertebra prominens. This can serve as a surface landmark
demarcating the neck (cervical) from the thoracic regions of the body.
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Anterior Neck
As with all regions of the body, your study should start out with a look at
the living region being studied. In the neck, the following diagram points out
the major landmarks of the neck.
 | Common carotid artery (cc) |
| Internal carotid artery (ic) |
| External carotid artery (ec) |
| Carotid sinus (cs) |
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Superficial structures that you should know
from the lateral view of the neck.
| sternomastoid |
| trapezius |
| occipital lymph nodes (on) |
| retroauricular lymph nodes (ran) |
| superficial cervical lymph nodes (scn)
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| submental lymph nodes (smn) |
| buccal lymph nodes (bn) |
| parotid lymph nodes (pn) |
| submandibular lymph nodes (not labeled but uner angle of mandible)
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It is very important to visually project deep structures onto the surface of
a person or patient when making educated clinical diagnoses. The first thing you
will usually do during a physical examination is to palpate any superficial
structure that you can so that you can tell if abnormal changes have occurred.
Swollen lymph nodes will tell you if there is an infection in an area that is
drained by the nodes. The superficial group of nodes in the neck drain the skin
of the face and nose, scalp and external ear. The submental nodes also drain the
tip of the tongue. Deeper regions of the head and neck drain into a deep group
of lymph nodes and are less palpable.
In the anterior neck, you can palpate the cartilages of the larynx and trachea.
The thyroid gland is closely associated with the cricoid cartilage and the
tracheal rings and should always be palpated in a general physical examination
of the neck. Another very important structure that is palpable is the carotid
artery. You should practice taking a carotid pulse since this is one site that
is probably most often used to check to see if a person is still living.
The carotid artery pulse can be felt by pushing lateral to the upper border of
the thyroid cartilage just under the anterior edge of the sternomastoid muscle.
Anterior Triangle of the Neck In Detail
The neck is arbitrarily subdivided into two triangles by the
sternocleidomastoid muscle:
Sternomastoid Region and Posterior Triangle of Neck
Table of Muscles
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Muscle
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Origin
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Insertion
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Action
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Nerve Supply
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| sternomastoid |
sternal head--manubrium of sternum; clavicular head--medial 1/3rd of
clavicle |
mastoid process, superior nuchal line |
rotates, extends the head; flexes the head |
spinal accessory |
| trapezius |
superior nuchal line; nuchal ligament; spinous processes of C7 and all
of thoracic |
superior part--lateral 1/3rd of clavicle; middle part--acomion
process and spine of scapula; inferior part--spine of scapula (middle
part) |
elevates shoulder; rotates scapula laterally to help raise shoulder;
retracts scapula |
spinal accessory; C2-C3 |
| splenius capitis |
spinous processes of upper thoracic vertebrae |
mastoid process and superior nuchal line |
extends and rotates head |
dorsal rami of thoracic nerves |
| levator scapulae |
transverse processes of C1-C4 |
upper medial border of scapula |
raises scapula |
dorsal scapular |
| scalene posterior |
transverse processes of C5-C7 |
upper surface of 2nd rib |
raises 2nd rib; bends neck to the side |
ventral rami of C7-C8 |
| scalene medius |
transverse processes of C1-C6 |
upper surface of 1st and 2nd ribs |
raises 1st rib; bends neck to side |
ventral rami of C3-C8 |
| scalene anterior |
transverse processes of C3-C6 |
scalene tubercle of 1st rib |
raises 1st rib; bends to side |
ventral rami of C6-C8 |
List of Items Covered in This Lesson
Muscles
sternomastoid
trapezius
splenius capitis & cervicis
levator scapulae
scalene posterior
scalene medius
scalene anterior
inferior belly omohyoid
Bones
mastoid process
occipital bone
superior nuchal line
clavicle
Arteries
common carotid
subclavian
occipital
transverse cervical
suprascapular
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Nerves
lesser occipital
great auricular
transverse cervical
spinal accessory
lower trunk of brachial
plexus
Veins
subclavian
external jugular
Lymph nodes
superficial cervical
deep cervical
omohyoid node
digastric node
Miscellaneous
carotid sheath
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Lateral Pharyngeal Region
In order to view the prevertebral region,
which we will do next, the pharynx and related structures should be cleaned
well so that they can be preserved when the pharynx and skull are reflected
forward.
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With the roof removed, you can see the boundaries of the carotid triangle
and the superficial veins related to it:
