Anatomy Flashcards
Who is the father of anatomy?
Herophilus
What is fascia?
Fascia is a thin casing of connective tissue that surrounds and holds every organ, blood vessel, bone, nerve fiber, and muscle in place. The tissue provides more than an internal structure; the fascia has nerves that make it almost as sensitive as skin.
Traditionally what are the two divisions of fascia?
- Superficial fascia
- Deep fascia
What are two characteristics of superficial fascia?
-‘Loose’ connective tissue
-Collagen and elastic fibres
What are two characteristics of deep fascia?
- Dense organized connective tissue
- Devoid of adipose tissue
Where is fascia found?
Throughout the body
Three elements (Location, thickness, distribution) between Superficial and deep fascia?
Superficial fascia
-Subcutaneous tissue
-Varies in thickness
-Varies in distribution
Deep fascia
-Deep to the superficial fascia
-Almost everywhere
-Investing fascia / Intermuscular septa
What are the one function of fascia and the seven sections it is active in?
-Packing and insulation
Active in:
-Thermoregulation
-Protective padding
-Support for tissues/organs
-Reduces friction
-Transmits mechanical force
-Proprioceptive feedback
-Myofascial system
Draw fascia and muscle compartments in the leg.
Check-in notion, clinical scenarios of fascia.
What is Compartment Syndrome, what does it affect, and how is it treated?
-Increased pressure caused by swelling of tissue or increase in fluid
-Affects functions of the muscles or nerves in the compartment
-Fasciotomy to relieve pressure in emergency
Where does infection tend to spread within?
Within fascial compartments, or in between fascial compartments
What fascia helps prevent the spread of infection from one compartment to another?
Deep fascia.
What connects the base of the skull to the superior mediastinum?
Cervical fascial planes.
What do nerves allow us to do?
Allow us to sense our environment - both internal and external plus respond appropriately to that environment.
What is the CNS composed of?
-Brain
-Spinal cord
What is the PNS composed of?
-All other nerve tissue not within the CNS
-Spinal Nerves
-Cranial nerves
-Autonomic Nerves
What are the four anatomic nerves?
-organs, smooth muscle, glands
-visceral afferents
-sympathetic nerves
-parasympathetic nerves
What are the two collections of nerve cell bodies?
In the CNS: Nucleus
In the PNS: Ganglion
What are the bundles of axons wrapped with?
Connective tissue
What are the 6 modalities for a single nerve fiber conduction?
Somatic sensory function
Somatic motor function
Special sensory function
Visceral afferent function
Sympathetic function
Parasympathetic function
What is the difference between efferent and afferent?
Efferent: Action potential towards the body wall, body cavity, or organ
Afferent: Actions potential towards the brain.
What is the cortex?
The outermost layer of the cerebral hemispheres
What are the groove and ridges in the brain called?
Sulcus and Gyrus
Tell me the 4 lobes of each cerebral hemisphere
Frontal, temporal, parietal and occipital
How many cranial nerves are there?
12 pairs
What are the 12 Cranial Nerves?
CN I : Olfactory nerve
CN II : Optic nerve
CN III : Oculomotor nerve
CN IV : Trochlear nerve
CN V : Trigeminal nerve
CN VI : Abducent nerve
CN VII : Facial nerve
CN VIII : Vestibulocochlear nerve
CN IX : Glossopharyngeal nerve
CN X : Vagus Nerve
CN XI : Spinal Accessory Nerve
CN XII : Hypoglossal Nerve
What is each of the cranial nerves, sensory or motor?
CN I : Sensory
CN II : Sensory
CN III : Motor
CN IV : Motor
CN V : Both
CN VI : Motor
CN VII : Both
CN VIII : Sensory
CN IX : Both
CN X : Both
CN XI : Motor
CN XII : Motor
Where does each nerve originate from? Draw it
Check.
What nerves go through the anterior cranial fossa?
CN I
What nerves go through the middle cranial fossa?
CN II, CN III, CN IV, CN Va, Vb & Vc, CN VI
What nerves go through the posterior cranial fossa?
CN VII, CN VIII, CN IX, CN XI and CN XII
What foramina does the CN I go through?
Cribriform plate of the ethmoid bone
What foramina does the CN II go through?
Optic canal
What foramina do the CN III, V1 & VI go through?
Superior orbital fissure
What foramina does the CN V2 go through?
Foramen rotundum
What foramina does the CN V3 go through?
Foramen ovale
What foramina do CN VII & VIII go through?
Internal acoustic meatus
What foramina does CN IX, X & XI?
Jugular foramen
What foramina does the CN XII go through?
Hypoglossal canal.
What does the Spinal Cord go through regarding the skull, and what is it protected by?
Foramen magnum and vertebral canal
What are the four segments and 2 enlargements in the spinal cord?
-Cervical, thoracic, lumbar, and sacral/coccygeal.
-Cervical and lumbosacral.
Why does the enlargement happen in the spinal cord?
Due to the limbs, more nerves are required.
What are the numbers of each spinal cord segment, and how do we clinically refer to each one?
Eight cervical - C1-C8
Twelve thoracic - T1-T12
Five lumbar - L1-L5
Five sacral - S1-S5
One coccygeal - Co
What level does the spinal cord end at, and how do we refer to it?
L1/L2 IV disk level– Named conus medullaris.
What is Cauda Equina, and what is it for?
Horsetail, lumbar and sacral spinal nerve roots must descend in the vertebral canal to their respective intervertebral foramina.
Regarding vertebrae, how many are there in each segment, and which ones fuse together?
-33 vertebrae in total
7 cervical
12 thoracic
5 lumbar
5 sacral
-fused to form 1 sacrum
4 coccygeal
-fused to form 1 coccyx
What is the rule for naming the spinal nerves?
- Spinal nerves are named according to the
vertebrae above it- except in the cervical region, where
they are named according to the
vertebrae below it
- except in the cervical region, where
What do the spinal nerves supply?
The soma (Body wall)
Where are the spinal nerves located?
ONLY WITHIN the intervertebral foramina.
What two structures do the intervertebral foramina connect with?
- Structures of the soma via rami
- The spinal cord via roots and rootlets
What do the posterior and anterior rami supply?
-Posterior rami
supply a small posterior strip
-Anterior rami
supply the remainder of the posterior part, the lateral and the anterior parts of the strips, and supply all of the limbs.
What are dermatomes?
Area (strip) of skin supplied by both the anterior and posterior rami of a spinal nerve.
What are the dermatomes for the nipple and umbilicus?
T4 dermatome – nipple
T10 dermatome – umbilicus
What are the four nerve plexuses?
-Cervical Plexus
-Brachial Plexus
-Lumbar Plexus
-Sacral Plexus
Where does the cervical plexus originate, and what does it innerve?
C1-C4 anterior rami
Posterior scalp, neck wall, and diaphragm
Where does the brachial plexus originate, and what does it innerve?
C5-T1 anterior rami
Upper limb
Where does the lumbar plexus originate, and what does it innerve?
L1-L4 anterior rami
Lower limb
Where does the sacral plexus originate, and what does it innerve?
L5-S4 anterior rami
Lower limb, gluteal region and perineum
What is the somatic nervous system?
The somatic nervous system consists of nerves that go to the skin and muscles and is involved in conscious activities.
What are the four sensations sensed by mechanoreceptors in the CNS?
Coarse touch
Fine touch
Vibration
Proprioception
What is sensed by thermoreceptors in between the CNS and PNS?
Temperature
What is sensed by the nociceptors in the PNS?
Pain
What are Spinal reflexes?
Involuntary rapid response which misses out the pathway to the brain.
What is the autonomic nervous system?
It is a component of the peripheral nervous system that regulates involuntary physiologic processes.
What are the two subdivisions of the autonomic nervous system?
Sympathetic and parasympathetic nervous systems.
What does the sympathetic division do to pupils, the heart, lungs, GI tract, liver, adrenal glands, arterioles, and skin?
Pupils - dilate
Heart - rate increases
Lungs - bronchioles dilate
GI tract - motility is reduced
Liver - glucose released into the blood
Adrenal glands - adrenaline/noradrenaline released
Arterioles - dilate (e.g., in skeletal muscle) or constrict (e.g., in the skin). Skin feels cold & looks pale
Skin - hair stands on end & sweat produced
What does the parasympathetic division do to the pupils, the heart, lungs, GI tract, liver, and bladder?
Pupils - constrict
Heart - rate decreases
Lungs - bronchioles constrict
GI tract - motility is increased
Liver - glucose synthesis
Bladder – sphincter relaxes
What is the objective of parasympathetic division?
Return the body to homeostasis and to compliment/oppose the sympathetic system.
At which level do the spinal nerves exit the spinal cord?
T1-L2
By what nerves does the sympathetic outflow travel to reach organs?
Splanchnic nerves.
What structure do only T1 to L2 have, and what are their names?
Lateral horns for cell bodies of the next sympathetic neurons in the chain.
-Paravertebral ganglion of the right sympathetic trunk (the trunk runs parallel to the vertebral column).