ANAT 316 Pt2

Aortic Valve activity: systole vs diastole

Aortic Valve activity: systole vs diastole

Common carotid bifurcates at carotid sinus

Travels upward and gives off several branches to head and neck

External Carotid Artery Branches

Upper limb blood supply

Hand blood supply

Thorax blood supply

Arch of Aorta → Subclavian → Internal Thoracic → Anterior Intercostal

Arch of Aorta → Descending Aorta → Posterior Intercostal

Pulmonary Circulation

Systemic Circulation

• Contributes to circle of Willis

• Passes through carotid canal

Head and Neck Venous Drainage

Superior Mesenteric Artery

• Anterior view

SMA: Ileal and Jejunal Arteries continued

Inferior Mesenteric Artery

Anastomoses between right, middle and left colic arteries - Creates circumference artery around entire large intestine

• Key for collateral circulation or alternative supply (compensatory measure)

  • A pathogen can turn the marginal artery into a hazard as it can spread across whole area

Pelvis Arterial Blood Supply

Pelvis Arterial Blood Supply

Pelvis → Upper Leg Arterial Blood Supply

Lower Leg Arterial Blood Supply

Abdomen Venous Drainage

Abdomen Venous Drainage

• Anterior view

Pelvis Venous Drainage

Leg Venous Drainage

Anterolateral Abdominal Wall - Muscles

• External Obliques point inferiorly toward the midline

• Internal Obliques point superiorly toward the midline

Transversus Abdominus runs horizontally

 Housed by the rectus sheathe despite not being part of the anterolateral wall, which is formed by the aponeuroses of the muscles in that group

Rectus Sheathe layers depend on…

Location

• Above or below the arcuate line

  • Between the umbilicus & pubis

Rectus Sheathe above the arcuate line

Rectus Sheathe below the arcuate line

Inguinal Region Overview

Surface Anatomy

• Left & right of the hypogastric region

Key Structures

• Inguinal Ligament

• Inguinal Canal

Inguinal Canal - Location

Inguinal Canal Features

Inguinal Canal Features

Inguinal Canal Borders

Inguinal Canal - Males

Inguinal Canal - Females

Abdominal Wall Sensory Innervation

Abdominal Wall Motor Innervation

Lumbar Plexus

Abdominal Lymphatic Drainage - Superficial

Abdominal Lymphatic Drainage - Deep

Abdominal Lymphatic Drainage - Return to Venous Circulation

Left abdomen & right abdomen below the umbilicus:

• Cisterna chyli → Thoracic duct → venous system

• Axillary nodes (left) → Thoracic duct → venous system

Right abdomen above the umbilicus:

• Axillary nodes (right) → Right lymphatic duct → venous system

Muscles of Facial Expression

• Superficial (subcutaneous) muscles

• Origins → facial bones or adjacent muscles

• Insertions → skin

Functions:

• Sphincters/Dilators

• Facial expression alteration

• Innervation: CN VII (temporal for the upper half & zygomatic for the lower half)

• Blood Supply: facial a., superficial temporal a. & ophthalmic a.

• Venous Drainage: facial v.

Muscles of Mastication

• Both superficial & deep muscles

Functions:

• Movement of the mandible

Superficial anterior neck muscles

Deep anterior neck muscles

Two groups

• Hyoid muscles

• Scalene muscles

Suprahyoid vs Infrahyoid muscles

C1 Through CN XII Sheath

C1 travels alongside hypoglossal nerve in the same sheathe and splits off to innervate geniohyoid and thyrohyoid

• Innervation: C3-8

• Blood Supply: inferior thyroid a.

• Venous Drainage: inferior thyroid v.

Superficial to deep dissection-based approach to reach the suboccipital triangle!

1. Remove/reflect trapezius

2. Remove/reflect splenius capitus

3. Reflect levator scapulae

4. Remove/reflect semispinalis capitis

5. Identify the Suboccipital Triangle

   Muscles!

Functions:

• Neck extension & rotation

• Postural support

Suboccipital Triangle Contents