Anterior Torso and Neck Flashcards
(41 cards)
1
Q
Anterior Torso and Neck
A
Platysma m.
Origin:
- Fascia of upper thorax and lower neck
Insertion:
- Mandible (lower border)
- Skin and fascia of lower face
- Blends with muscles of lower lip and angle of mouth.
Innervation:
- Facial nerve (CN VII)
Action(s):
- Tenses skin of neck and pulls lower lip inferiorly
- Tenses skin of neck and pulls lower lip inferiorly with skin
Layer 2: Muscle
2
Q
Anterior Torso and Neck
A
Sternocleidomastoid
Origin:
- Clavicle (medial)
- Sternum (manubrium)
Insertion:
- Mastoid process of temporal bone
- Lateral one-half of superior nuchal line of occipital bone
Innervation:
- Accessory nerve (CN XI)
Action(s):
- Unilateral: rotation of head so face turns to opposite side
- Bilateral: flexion of neck
- Bilateral: extension of head
Layer 2: Muscle
3
Q
Anterior Torso and Neck
A
Omohyoid
Origin:
- Scapula (superior border)
Insertion:
- Hyoid bone
Innervation:
- Ventral rami of C1-3 spinal nerves (ansa cervicalis)
Action(s):
- Depression of hyoid bone
Layer 2: Muscle
4
Q
Anterior Torso and Neck
A
Sternohyoid
Origin:
- Sternum (manubrium)
- Clavicle (medial end)
Insertion:
- Hyoid bone
Innervation:
- Ventral rami of C1-3 spinal nerves (ansa cervicalis)
Action(s):
- Depression of hyoid bone
Layer 2: Muscle
5
Q
Anterior Torso and Neck
A
Sternothyroid
Origin:
- Sternum (manubrium)
Insertion:
- Thyroid cartilage of larynx
Innervation:
* Ventral rami of C1-3 spinal nerves (ansa cervicalis)
Action(s):
- Depression of larynx
Layer 3: Muscle
Comment:
- One of four infrahyoid muscles: sternohyoid, sternothyroid, omohyoid, and thyrohyoid
- Ansa cervicalis (Latin: ansa = loop; cervicalis = neck) is a nerve “loop” formed by ventral rami of C1-3 spinal nerves
- Thyrohyoid is not innervated by ansa cervicalis
6
Q
Anterior Torso and Neck
A
Thyrohyoid
Origin:
- Thyroid cartilage of larynx
Insertion:
- Hyoid bone
Innervation:
- Ventral ramus of C1 spinal nerve
Action(s):
- Elevation of larynx
- Depression of hyoid bone
Layer 3: Muscle
Comment:
- One of four infrahyoid muscles: sternohyoid, sternothyroid, omohyoid, and thyrohyoid
- Only infrahyoid muscle NOT innervated by ansa cervicalis
- Ansa cervicalis (Latin: ansa = loop; cervicalis = neck) is a nerve “loop” formed by ventral rami of C1-3 spinal nerves
7
Q
Anterior Torso and Neck
A
Inferior Pharyngeal Constrictor
Origin:
- Pterygomandibular raphe (superior constrictor)
- Hyoid bone (middle constrictor)
- Thyroid and cricoid cartilages of larynx (inferior constrictor)
Insertion:
- Posterior midline raphe
- Base of skull (superior constrictor)
Innervation:
- Vagus nerve (CN X)
Action(s):
- Produces a wave of contraction (peristalsis) during swallowing
Layer 3: Muscle
8
Q
Anterior Torso and Neck
A
Scalene (Anterior, Middle, and Posterior)
Origin:
- Transverse processes of C3-7 vertebrae
Insertion:
- Anterior: rib 1
- Middle: rib 1
- Posterior: rib 2
Innervation:
- Ventral rami of cervical spinal nerves
Action(s):
- Anterior: elevation of rib 1; lateral flexion and rotation of neck
- Middle: elevation of rib 1; lateral flexion of neck
- Posterior: elevation of rib 2; lateral flexion of neck
Layer 3: Muscle
Comment:
- Neck movements produced when rib is fixed
- Important accessory muscles of respiration
- Important anatomical relationship: roots of brachial plexus found between anterior and middle scalene muscles
9
Q
Anterior Torso and Neck
A
Mylohyoid
Origin:
- Mandible (inner aspect of body)
Insertion:
- Hyoid bone (posterior fibers)
- Midline fibrous raphe (anterior fibers)
Innervation:
- Trigeminal nerve (mandibular division - CN V3)
Action(s):
- Elevation of floor of mouth
Chin: Muscle
Comment:
- Four suprahyoid muscles: digastric, geniohyoid, mylohyoid, and stylohyoid
- A raphe is a “seam” where two structures meet
10
Q
Anterior Torso and Neck
A
Digastric
Origin:
- Anterior belly: mandible (inner aspect of body near midline)
- Posterior belly: temporal bone (mastoid process)
Insertion:
- Hyoid bone
Innervation:
- Anterior belly: trigeminal nerve (mandibular division - CN V3)
- Posterior belly: facial nerve (CN VII)
Action(s):
- Depression of mandible (opens mouth)
- Elevation of hyoid bone
Chin: Muscle
11
Q
Anterior Torso and Neck
A
Stylohyoid
Origin:
- Styloid process of temporal bone
Insertion:
- Hyoid bone
Innervation:
- Facial nerve (CN VII)
Action(s):
- Elevation of hyoid bone
Chin: Muscle
Comment:
Four suprahyoid muscles:
- digastric
- geniohyoid
- mylohyoid, and
- stylohyoid
12
Q
Anterior Torso and Neck
A
Pectoralis Major
Origin:
- Clavicular head: clavicle (medial part)
- Sternocostal head: sternum, costal cartilages 1-6, and aponeurosis of external abdominal oblique muscle
Insertion:
- Humerus (lateral lip of intertubercular sulcus)
Innervation:
- Lateral pectoral nerve (C5-7)
- Medial pectoral nerve (C8-T1)
Action(s):
- Adduction of arm
- Medial rotation of arm
- Clavicular head: flexion of arm
- Sternocostal head: extension of arm (from flexed position)
Thorax: Muscle
Comment:
- Pectoralis major and minor muscles also known as “pecs”
- Pectoralis major active during forced inspiration
13
Q
Anterior Torso and Neck
A
Pectoralis Minor
Origin:
- Ribs 3-5
Insertion:
- Scapula (coracoid process)
Innervation:
- Medial and lateral pectoral nerves
Action(s):
- Stabilizes scapula (holds it against thoracic wall)
- Protraction (abduction) of scapula (assists serratus anterior)
- Lateral rotation of scapula (e.g., depresses the acromion)
Thorax: Muscle
Comment:
- Pectoralis major and minor muscles also known as “pecs”
- Pectoralis minor active during forced inspiration
14
Q
Anterior Torso and Neck
A
Subclavius
Origin:
- Rib 1 and its costal cartilage
Insertion:
- Clavicle (middle third)
Innervation:
- Nerve to subclavius
Action(s):
- Depression and stabilization of clavicle
Thorax: Muscle
15
Q
Anterior Torso and Neck
A
Serratus Anterior
Origin:
- Ribs 1-9
Insertion:
- Scapula (medial border)
Innervation:
- Long thoracic nerve
Action(s):
- Protraction (abduction) of scapula
- Superior rotation of scapula (directs glenoid cavity superiorly)
- Stabilizes scapula (holds it against thoracic wall)
Thorax: Muscle
Comment:
- Serratus anterior is a prime mover in all reaching and pushing movements
16
Q
Anterior Torso and Neck
A
External Intercostal & Membrane
Origin:
- Inferior border of rib (ribs 1-11)
Insertion:
- Superior border of rib below (ribs 2-12)
Innervation:
- Intercostal nerves (ventral rami of T1-11 spinal nerves)
Action(s):
- Muscle of respiration
- Elevation of ribs during inhalation to increase transverse dimensions (anterior-posterior, medial-lateral) of thoracic cavity
Intercostal: Muscle
Comment:
- External intercostal muscle continuous with external intercostal membrane near sternum
- In contemporary medical anatomy books, the origins of external and internal intercostal muscles are referred to as “superior attachments” and described for both muscles as the inferior border of the rib.
- Similarly, the insertions of these muscles are referred to as “inferior attachments” and described as the superior border of the rib below.
17
Q
Anterior Torso and Neck
A
Internal Intercostal (no photo of membrane)
Origin:
- Superior border of rib (ribs 1-11)
Insertion:
- Inferior border of rib above (ribs 2-12)
Innervation:
- Intercostal nerves (ventral rami of T1-11 spinal nerves)
Action(s):
- Muscle of respiration
- Depression of ribs during forced exhalation to decrease transverse dimensions (anterior-posterior, medial-lateral) of thoracic cavity
Intercostal: Muscle
Comment:
- Internal intercostal muscle continuous with internal intercostal membrane lateral to vertebral column
- Muscle fibers run inferoposteriorly
- In contemporary medical anatomy books, the origins of external and internal intercostal muscles are referred to as “superior attachments” and described for both muscles as the inferior border of the rib.
- Similarly, the insertions of these muscles are referred to as “inferior attachments” and described as the superior border of the rib below.
18
Q
Anterior Torso and Neck
A
Innermost Intercostal
Origin:
*
Insertion:
*
Innervation:
*
Action(s):
*
Intercostal: Muscle
19
Q
Anterior Torso and Neck
A
Transversus Thoracis
Origin:
- Inferoposterior surface of body of sternum and xiphoid process; sternal ends of costal cartilages of ribs 4-7
Insertion:
- Internal surface of costal cartilages of ribs 2-6
Innervation:
- Intercostal nerves
Action(s):
- Depresses ribs during forced expiration; Supports intercostal spaces and thoracic cage
Intercostal: Muscle
20
Q
Anterior Torso and Neck
A
Rectus Abdominus
Origin:
- Pubis (crest and symphysis)
Insertion:
- Sternum (xiphoid process)
- Costal cartilages 5-7
Innervation:
- Ventral rami of T7-12 spinal nerves
Action(s):
- Flexion of trunk (sit-ups)
- Compression of anterior abdominal wall
Abdomen: Muscle
Comment:
- Three or four bellies, separated by tendinous intersections
- Encased in fibrous (rectus) sheath
- Important in “straining” (e.g., lifting, defecation, urination, child-birth)
- Functions in respiration (“abdominal breathing”)
21
Q
Anterior Torso and Neck
A
Linea Alba
Location:
- Anterior abdominal wall (midline)
Description:
- Fibrous raphe formed by paired rectus sheaths
Abdomen:
Comment:
- Umbilicus located in linea alba
- Opening abdominal cavity by incision through linea alba avoids cutting muscle fibers
- A raphe is a “seam” where two structures meet
22
Q
Anterior Torso and Neck
A
External Oblique
Origin:
- Ribs and costal cartilages 5-12
Insertion:
- Linea alba
- Ilium (crest)
Innervation:
- Ventral rami of T8-L1 spinal nerves
Action(s):
- Unilateral: rotation of trunk
- Bilateral: flexion of trunk (sit-ups)
- Compression of anterior abdominal wall and viscera (increases intra-abdominal pressure)
Abdomen: Muscle
Comment:
- Important in “straining” (e.g., lifting, defecation, urination, child-birth)
- Functions in respiration (“abdominal breathing”)
- At right angle to internal abdominal oblique (strengthens abdominal wall)
23
Q
Anterior Torso and Neck
A
Internal Oblique
Origin:
- Inguinal ligament
- Ilium (crest)
- Thoracolumbar fascia
Insertion:
- Linea alba
- Costal cartilages 7-10
Innervation:
- Ventral rami of T8-L1 spinal nerves
Action(s):
- Unilateral: rotation of trunk
- Bilateral: flexion of trunk (sit-ups)
- Compression of anterior abdominal wall and viscera (increases intra-abdominal pressure)
Abdomen: Muscle
Comment:
- Important in “straining” (e.g., lifting, defecation, urination, child-birth)
- Functions in respiration (“abdominal breathing”)
- At right angle to external abdominal oblique (strengthens abdominal wall)
24
Q
Anterior Torso and Neck
A
Transverse Abdominus
Origin:
- Ilium (crest)
- Inguinal ligament
- Thoracolumbar fascia
- Costal cartilages 7-12
Insertion:
- Pubis (body)
- Linea alba
- Sternum (xiphoid process)
Innervation:
- Ventral rami of T8-L1 spinal nerves
Action(s):
- Compression of anterior abdominal wall and viscera (increases intra-abdominal pressure)
Abdomen: Muscle
Comment:
- Important in “straining” (e.g., lifting, defecation, urination, child-birth)
- Functions in respiration (“abdominal breathing”)
25
## Footnote
*Anterior Torso and Neck*
Medial Pectoral n.
**Location**:
* Axilla
* Thoracic wall (superior lateral)
**Contributions**:
* Ventral rami of C8-T1 spinal nerves
**Composition**:
* Motor
**Motor**:
* Pectoralis major
* Pectoralis minor
**Comment**:
* Named for origin from medial cord of brachial plexus
* Pierces pectoralis minor to enter pectoralis major
* Brachial plexus roots = ventral rami of C5-T1 spinal nerves
## Footnote
*Neurology*
26
## Footnote
*Anterior Torso and Neck*
Lateral Pectoral n.
**Location**:
* Axilla
* Thoracic wall (superior lateral)
**Contributions**:
* Ventral rami of C5-7 spinal nerves
**Composition**:
* Motor
**Motor innervation**:
* Pectoralis major and minor
**Comment**:
* Named for origin from lateral cord of brachial plexus
* Brachial plexus roots = ventral rami of C5-T1 spinal nerves
## Footnote
*Neurology*
27
## Footnote
*Anterior Torso and Neck*
Long Thoracic n.
**Location**:
* Neck (inferior)
* Thoracic wall (lateral) - on superficial surface of serratus anterior
**Contributions**:
* Ventral rami of C5-7 spinal nerves
**Composition**:
* Motor
**Motor**:
* Serratus anterior
**Comment**:
* Brachial plexus roots = ventral rami of C5-T1 spinal nerves
## Footnote
*Neurology*
28
## Footnote
*Anterior Torso and Neck*
Thoracodorsal n.
**Location**:
* Thoracic wall (superior lateral)
**Contributions**:
* Ventral rami of C6-8 spinal nerves
**Composition**:
* Motor
**Motor**:
* Latissimus dorsi
**Comment**:
* Brachial plexus roots = ventral rami of C5-T1 spinal nerves
## Footnote
*Neurology*
29
## Footnote
*Anterior Torso and Neck*
Intercostal n.
**Location**:
* Intercostal spaces
* Between innermost and internal intercostal muscles
**Contributions**:
* Ventral rami of T1-11 spinal nerves
**Composition**:
* Motor and general sensation
**Motor**:
* Intercostal muscles
* Anterior abdominal wall muscles (T7-11)
**General sensation**:
* Skin of thorax (T1-11), abdomen (T7-11) and upper limb (T2)
* Parietal pleura (costal and peripheral diaphragmatic) (T1-11)
* Parietal peritoneum (T7-11)
## Footnote
*Neurology*
30
## Footnote
*Anterior Torso and Neck*
Phrenic n.
**Location**:
* Neck (inferior)
* Thorax (mediastinum)
**Contributions**:
* Ventral rami of C3-5 spinal nerves
**Composition**:
* Motor
* General sensation
**Motor**:
* Diaphragm
**General sensation**:
* Parietal layer of pleura and peritoneum over central diaphragm
* Mediastinal pleura
* Parietal pericardium
**Comment**:
* Supplies all motor innervation to diaphragm (hint: remember C3, 4, 5 "keeps the diaphragm alive")
## Footnote
*Neurology*
31
## Footnote
*Anterior Torso and Neck*
Vagus n.
**Location**:
* Posterior cranial fossa
* Head
* Neck
* Thorax
* Abdomen
* Composition:
* Motor
* General sensation
* Special sensation
* Parasympathetic
* Motor:
* Muscles of palate
* Muscles of pharynx
* Intrinsic muscles of larynx
**General sensation**:
* Thoracic and abdominal viscera
* Epiglottis and laryngopharynx
* External acoustic meatus
* Special sensation:
* Taste from epiglottis and surrounding region
**Parasympathetic**:
* Mucous glands of respiratory and digestive systems in neck (pharynx and larynx), thorax, and abdomen
* Smooth muscle of respiratory and digestive systems in neck (pharynx and larynx), thorax, and abdomen
* Cardiac muscle
**CNS connection**:
* **Motor**: medulla oblongata (nucleus ambiguus)
* **General sensation**: medulla oblongata (spinal nucleus of trigeminal nerve)
* **Special sensation**: medulla oblongata (nucleus of solitary tract)
* **Parasympathetic**: medulla oblongata (dorsal nucleus of vagus nerve)
* **Cranial foramina**:
* Jugular foramen
**Comment**:
* General sensation from thoracic and abdominal viscera only involves stretch (e.g., distention of stomach)
* General sensation from epiglottis and laryngopharynx includes pain, touch, and temperature
* Vagus nerve also innervates carotid and aortic bodies
* Parasympathetic impulses from CNS to effector organ involve two neurons in series (preganglionic and postganglionic)
* Only cranial nerve that extends beyond head and neck
* Vagus nerve also known as CN X
## Footnote
*Neurology*
32
## Footnote
*Anterior Torso and Neck*
Sympathetic Trunk
**Location**:
* Adjacent to vertebral bodies, from base of skull to coccyx
**Description**:
* Nerve trunk comprised of axons connecting sympathetic (paravertebral) ganglia
* Sympathetic ganglia contain postganglionic nerve cell bodies
* Branches include gray and white rami communicans, and splanchnic nerves
**Also known as**:
* Sympathetic chain
* Sympathetic chain ganglia
* Comment:
* Ganglia give trunk a "beaded" appearance
## Footnote
*Neurology*
33
## Footnote
*Anterior Torso and Neck*
Hypoglossal n.
**Location**:
* Posterior cranial fossa
* Neck
* Oral cavity
* Composition:
* Motor
* Motor:
* Genioglossus
* Hyoglossus
* Styloglossus
* Intrinsic muscles of tongue
**CNS connection**:
* Medulla oblongata (nucleus of hypoglossal nerve)
* Cranial foramina:
* Hypoglossal canal
**Comment**:
* Hypoglossal nerve innervates all tongue muscles except palatoglossus (vagus nerve)
* Intrinsic tongue muscles originate and insert within tongue
* Hypoglossal nerve also known as CN XII
## Footnote
*Neurology*
34
## Footnote
*Anterior Torso and Neck*
Superior Laryngeal n.
## Footnote
*Neurology*
35
## Footnote
*Anterior Torso and Neck*
Internal Thoracic a.
**Origin**:
* Subclavian
**Course**:
* Descends adjacent to sternum within thoracic cavity
**Distribution**:
* Intercostal spaces
* Breast
* Pericardium
* Diaphragm
* Anterior abdominal wall
**Branches**:
* Anterior intercostal
* Pericardiacophrenic
* Superior epigastric
* Musculophrenic
**Also known as**:
* Internal mammary artery
## Footnote
*Angiology*
36
## Footnote
*Anterior Torso and Neck*
Internal Thoracic v.
**Drainage**:
* Anterior thoracic wall, including breast
* Anterior abdominal wall
* Diaphragm
* Pericardium
* Tributaries:
* Musculophrenic
* Superior epigastric
* Pericardiacophrenic
* Anterior intercostal
**Course**:
* Ascends posterior to costal cartilages, just lateral to sternum
* Termination:
* Subclavian
**Also known as**:
* Internal mammary vein
* Comment:
* Formed by union of superior epigastric and musculophrenic veins
37
## Footnote
*Anterior Torso and Neck*
Thoraco-acromial a.
**Origin**:
* Axillary
**Course**:
* Short artery medial to pectoralis minor muscle
**Distribution**:
* Anterior shoulder region
Mammary gland
**Branches**:
* Pectoral
* Deltoid
* Clavicular
* Acromial
## Footnote
*Angiology*
38
## Footnote
*Anterior Torso and Neck*
Thoraco-acromial v.
**Drainage**:
* Anterior shoulder region
* Mammary gland
**Tributaries**:
* Pectoral
* Deltoid
* Clavicular
* Acromial
**Course**:
* Short vein medial to pectoralis minor muscle
* Termination:
* Axillary
39
## Footnote
*Anterior Torso and Neck*
Superior Thoracic a./v.
## Footnote
*Angiology*
40
## Footnote
*Anterior Torso and Neck*
Lateral Thoracic a./v.
## Footnote
*Angiology*
41
## Footnote
*Anterior Torso and Neck*
Thoracodorsal a./v.
## Footnote
*Angiology*
