Anatomy Flashcards
Jaw opening occurs at which location (2)
Temporomandibular joint
Located at temporal bone, articular tubercle and head of condylar process
3 pairs of jaw closing muscles
Masseter
Temporalis
Medial Pterygoid
Pair of jaw opening muscles
Lateral Pterygoid
What nerve supplies the jaw muscle pairs (2)
Mandibular division of trigeminal nerve (3rd division) - CN V3
Contains sensory and motor fibres
Course of CN V3 (3)
From pons
Through foramen ovale
To muscles of mastication (chewing) and sensory area
Vestibule of oral cavity location
Between lips and teeth
Adult dentition (4)
32 teeth
All erupt by age 18
Consists of 4 quadrants (Upper left, upper right, lower left, lower right)
Incisor (1 and 2), Canine (3), Premolars (4 and 5), Molars (6 to 8)
Why ask for loose teeth/fillings
For choking hazard or aspiration risk
Major salivary glands types and locations in mouth (3)
Parotid - Duct arises at buckle of 2nd molar
Submandibular - Arises at frenulum of tongue
Sublingual - Under tongue
Sensation of superior half of oral cavity (2)
Sensation of CN V2
At gingiva of oral cavity and palate
Sensation of inferior half of oral cavity (2)
Sensation of CN V3
At gingiva of oral cavity and floor of mouth
Course of CN V2 (3)
Has sensory fibres from pons
Through foramen ovale
To sensory area
Spraying a local anaesthetic in oral cavity blocks AP in which nerves (4)
CN V2
CN V3
CN VII
CN IX
Anterior 2/3 tongue sensation (4)
Horizontal
In oral cavity
General sensory mediated by CN V3
Special sensory mediated by CN VII
Posterior 1/3 tongue sensation (3)
Vertical
Not in oral cavity
General and sensory mediated by CN IX
Components and course of CN VII (3)
Has special sensory, sensory, motor and parasympathetic fibres
From pontomedullary junction
Travel through temporal bone via internal acoustic meatus then stylomastoid foramen
CN VII supplies (3)
Taste anterior 2/3 of tongue
Muscles of facial expression - Via chorda tympani branch
Glands in floor of mouth
4 pairs of tongue extrinsic muscles and function
Palatoglossus Styloglossus Hyoglossus Genioglossus Changes position of tongue during speech, mastication and swallowing
4 pairs of intrinsic skeletal muscle location and function
Located mainly dorsally/posteriorly
Modify the shape of the tongue during function
Supply of tongue muscle (2)
CN XII
EXCEPT palatoglossus
Components and course of CN XII (4)
Has motor fibres
From medulla
Through hypoglossal canal
To extrinsic and intrinsic muscle of tongue
Components and course of CN XII (4)
Has motor fibres
From medulla
Through hypoglossal canal
To extrinsic and intrinsic muscle of tongue
Upper oesophageal sphincter location
Anterior to C6
Longitudinal muscles of pharynx features (6)
Inner layer Supplied mainly by CN X and IX Elevate pharynx and larynx Attaches to larynx too Contract to shorten pharynx Raises larynx to close over the laryngeal inlet
Anatomy of swallowing (5)
Close lips to prevent drooling
Tongue pushes the bolus posteriorly towards the
oropharynx
Sequentially contract the pharyngeal constrictor muscles to push the bolus inferiorly towards the oesophagus
At same time the inner longitudinal layer of pharyngeal muscles contracts to raise larynx, shortening the pharynx and closing
off the laryngeal inlet to help prevent aspiration
The bolus reaches the oesophagus
Oesophagus (3)
Inferior continuation of laryngopharynx
Begins at inferior edge of cricopharyngeus muscle (vertebral level C6)
Has an anatomical upper sphincter (cricopharyngeus) and a physiological lower oesophageal sphincter
Oesophageal plexus (5)
Runs on smooth muscle surface within walls
Contains parasympathetic and sympathetic nerve fibres
Parasympathetic speeds up peristalsis
Sympathetic reduces peristalsis
Terminates by entering stomach cardia
Oesophageal constriction points (3)
Cervical constriction - Cricopharyngeus muscle
Thoracic constriction - At aortic arch and left main bronchus
Diaphragmatic constriction - At T10, result of passing through diaphragm
(Lower oesophageal sphincter)
Lower Oesophageal Sphincter (4)
Physiological
Sphincter effect caused by diaphragm contraction, higher intrabdominal then intragastric pressure, oblique angle where oesophagus meets stomach cardia
Stomach location and shape
Lies in left hypochondrium, epigastric and umbilical regions when the patient is supine
J shaped - 50 to 1000 ml capacity
Presence of hiatus hernia and lower oesophageal sphincter (3)
Increases reflux occurrence
Lies immediately superior to gastro-oesophageal junction
Abrupt change in mucosa lining type - Forms Z line
Large intestine from proximal to distal features (9)
Caecum => Appendix => Ascending colon => Transverse colon => Descending colon => Sigmoid colon => Rectum => Anal canal => Anus
All organs in each foregut, midgut or hindgut region are supplied by (4)
Arterial blood from common artery
Venous drain from common vein
Lymphatic drainage via shared route
Nerve supply from common route
9 abdominal regions
Left/Right Hypochondrium Epigastric Left/Right Lumbar (Flank) Umbilical Left/Right Inguinal (Iliac fossa) Pubic (Suprapubic)
4 abdominal quadrants
Right/Left Upper Quadrants
Right/Left Lower Quadrants
Peritoneal Cavity characteristics (5)
Thin, transparent, semi permeable serous membrane
Continuous lining of abdominopelvic cavity wall
Is in contact with body wall (soma) is parietal and with the organs is visceral - Has peritoneal cavity in between layers
Is sensitive with nerve supply
Secretes small amount of lubricating fluid
Organ class in relationship to peritoneal cavity (3)
Intraperitoneal - Completely wrapped
Retroperitoneal - Partially wrapped
With a mesentery - Double layer
Intraperitoneal organ
Liver
Retroperitoneal organs (2)
Pancreas
Kidney
Organs with a mesentery organs
Parts of intestines
Peritoneum condensations (4)
Double layers
Attach organs to each other or to abdominal wall
Secondary to growth and rotation of GI tract during embryology
Visible during dissection and surgery
Peritoneum condensations examples
Greater omentum
Lesser omentum
Greater omentum (2)
Has nerves, lymphatics and blood vessels
During infection of abdominal cavity its wraps around the infected region preventing further infection
Omenta division parts (4)
Greater sac
Lesser sac
They communicate through omental foramen
Portal triad lies in free edge of lesser omentum
Inferior part of peritoneum
Drapes over superior pelvic organs
1 pouch in males - Rectovesical
2 pouches in females - Vesico-uterine and recto-uterine
Pouches are part of greater sacs
Ascites (3)
Excess fluid in peritoneal cavity
Secondary to liver disease
Drained by paracentesis
Paracentesis procedure (2)
Needle placed lateral to rectus sheath - Avoids inferior epigastric artery
Ultrasound guidance is available
Abdominal pain main questions (4)
Location - Anatomy and is pain localized
Character - Visceral (dull, achy, nauseating) or somatic (sharp, stabbing)
Timing - ‘Colicky pain’
Pain referral pattern - Is it showing classical distribution suggesting pathology of a specific organ
Abdomen nerves of organs (3)
INCLUDES visceral peritoneum
Visceral afferents
Autonomic motor nerves (Parasympathetic and Sympathetic) - Influences enteric nervous system
Abdomen nerves of body wall (3)
Somatic sensory
Somatic motor
Sympathetic nerve fibres
Sympathetic nerve pathway (4)
Leave spinal cord at levels T5 and L2
Enter sympathetic chains bilaterally but DO NOT synapse
Leave sympathetic chains within abdominopelvic splanchnic nerves
Synapse at prevertebral ganglia located anterior to aorta at the exit points of the major branches of abdominal aorta
Sympathetic nerve pathway - After synapsing
Postsynaptic sympathetic nerve fibres pass from prevertebral ganglia onto surface of arterial branches leaving the abdominal aorta
Sympathetic nerves to adrenal gland (3)
Same as the rest but leaves spinal cord at T10 - L1
Are carried with periarterial plexuses to adrenal gland
Synapse directly onto cells
Parasympathetic nerve pathway - Vagus nerve (4)
Presynaptic parasympathetic nerve fibres enter abdominal cavity on surface of oesophagus
Travels into periarterial plexuses around abdominal aorta
Carried to walls of organs where they synapse in ganglia
Supply Parasympathetic nerve fibres to the GI tract + abdominal organs up to distal end of the transverse colon
Parasympathetic nerve pathway - Pelvic Splanchnic Nerves (S2,3,4)
(2)
Presynaptic parasympathetic nerve fibres
Smooth muscle/glands of descending colon to anal canal
Abdominal pain regions
Foregut - Felt in epigastric region
Midgut - Felt in umbilical region
Hindgut - Felt in pubic region
Visceral afferent nerve fibres (5)
Pain fibres from abdominal organs run alongside sympathetic fibres back to spinal cord
Foregut - T6 to T9
Midgut - T8 to T12
Hindgut - T10 to L2
Pain from these organs tends to be perceived by patient in dermatomes of the levels at which they enter the spinal cord - Refereed pain
Appendicitis (3)
Midgut organ - Located in right Iliac fossa
Dull pain is felt in umbilical region as visceral afferents of these organs enter spinal cord at T8 - T10
As it worsens appendix rubs on parietal peritoneum and since its part of the soma the pain from dull becomes sharp
Jandice is caused by
Build up of bilirubin
Bilirubin characteristics (2)
By-product of RBC break down - Occurs in spleen and liver
Used to form bile in the liver
How does bile enter the duodenum
Through the biliary tree - Set of tubes connecting liver to 2nd part of duodenum
Portal triad (2)
Found in free edge of lesser momentum
Consists of hepatic artery, hepatic portal vein (Both carry blood to liver) and common bile duct
Celiac trunk characteristics (6)
1st of 3 midline branches of abdominal aorta
Is retroperitoneal
Arises around T12 vertebral level
Supplies organs of foregut
Trifurcates into 3 branches - Splenic, Hepatic and Left Gastric arteries
Each of these arteries further branch out to gastroduodenal and Superior pancreatico-duodenal
Spleen characteristics (5)
Splenic artery has tortuous course - Superior pancreas border
Intraperitoneal organs within left hypochondrium
Protected by ribs 9-11
Functions within haematological and immunological systems
Has blood reserves and produces RBC in infancy
Spleen anatomically related to (4)
The diaphragm posteriorly
The stomach anteriorly
The splenic flexure inferiorly
The left kidney medially
Spleen palpation (3)
Felt during end inspiration
Has clinical implication
Normally not palpable - Palpation present with enlargement over 3 times its normal size
Blood supply of stomach (2)
Right and left gastric arteries - Anastomose and run on lesser curvature
Right and left gastro-omental - Anastomose and run over greater curvature
Blood supply of liver (3)
Hepatic artery
Branches into left and right hepatic arteries
Arteries account for around 25% of blood received - Rest is by hepatic portal vein
Liver characteristics (4)
Mainly in upper right quadrant
Major metabolic organ
Protected by ribs 7-11
Can be described as 4 anatomical segments or 8 functional segments
Liver anatomically related to (5)
The diaphragm superiorly, anteriorly, posteriorly
The anterior aspect of the stomach medially
The gallbladder posterior & inferiorly
The hepatic flexure inferiorly
The right kidney, right adrenal gland, IVC and abdominal aorta posteriorly