DPT 604 Human Anatomy II Flashcards

Muscles of the Eye

  • Nerves Controlling Eye Muscles
    • CN III (Oculomotor): Controls superior, inferior, and medial recti, and inferior oblique muscles.
    • CN IV (Trochlear): Controls the superior oblique muscle.
    • CN VI (Abducens): Controls the lateral rectus muscle.
  • Eye Muscles, Cranial Nerves, and Actions
    • Superior rectus: III, UP
    • Inferior rectus: III, DOWN
    • Medial rectus: III, INWARD
    • Inferior Oblique: III, UP and OUT
    • Lateral rectus: VI, External Rotation (Horizontal plane)
    • Superior Oblique: IV, DOWN & IN
  • Eye movement tracking can assess eye muscle function.
  • Bones of the Orbit: There are 7 bones that form the orbit: Sphenoid, Ethmoid, Lacrimal, Frontal, Palatine, Maxillary, Zygomatic

Cranial Nerves

  • List of Cranial Nerves (CN)
    • CN I: Olfactory (Sensory)
    • CN II: Optic (Sensory)
    • CN III: Oculomotor (Motor)
    • CN IV: Trochlear (Motor)
    • CN V: Trigeminal (Both)
    • CN VI: Abducens (Motor)
    • CN VII: Facial (Both)
    • CN VIII: Vestibulocochlear (Sensory)
    • CN IX: Glossopharyngeal (Both)
    • CN X: Vagus (Both)
    • CN XI: Spinal Accessory (Motor)
    • CN XII: Hypoglossal (Motor)
  • CNs Associated with Facial Expression and Chewing
    • Facial Nerve (CN VII): Facial expression
    • Trigeminal Nerve (CN V3): Muscles of mastication
  • Cranial Nerve Testing Demonstrations (Refer to Monica Zimmerman Video)
    • I: Smell test with coffee, peppermint, or vanilla, while eyes are closed and one nostril is occluded.
    • II: Sight test, covering one eye at a time.
    • III: Follow finger up and down.
    • IV: Look down and in.
    • V: Sensation test on the face (forehead, cheek, jaw) on both right and left sides.
    • VI: Follow finger to the right and left.
    • VII: Test symmetry by having the patient smile, lift eyebrows, and frown.
    • VIII: Rub fingers together near the ear to check hearing.
    • IX: Have the patient swallow.
    • X: Have the patient swallow and cough.
    • XI: Have the patient elevate shoulders.
    • XII: Have the patient stick out their tongue and check for symmetry.
  • Cribriform Plate
    • Location: Superior part of the ethmoid bone.
    • Function: Acts as a placeholder for the olfactory bulbs, with perforations allowing odors to contact the olfactory bulbs.
  • Acoustic Neuroma Case
    • A 64-year-old male diagnosed with an acoustic neuroma (tumor of the 8th cranial nerve) where it enters the temporal bone.
    • Involved Cranial Nerve: Facial Nerve (CN VII)
    • Explanation: Both CN VII (Facial) and CN VIII (Vestibulocochlear) enter the temporal bone via the internal acoustic meatus. CN VII exits via the internal acoustic meatus and leaves the skull through the stylomastoid foramen. Abducens (CN VI), oculomotor CN III), troclear (CN IV), and the ophthalmic division trigeminal (CN V/1) cross through the superior orbital fissure. Glossopharyngeal (CN IX), vagus (CN X), and spinal accessory (CN XI) all exit via the jugular foramen.
    • The 3 divisions (V1, V2, V3) of trigeminal (CN V) all exit via different foramens: CNV V1 (ophthalmic division)) leaves via the superior orbital fissure, CNV V2 (maxillary division)) exits via foramen rotundum, CN V V3 (mandibular) exits foramen ovale
  • Facial Nerve Palsy (Bell’s Palsy) Case
    • A 14-year-old female experiences immediate paralysis of the left face while snow skiing.
    • Affected Nerve: Left Facial Nerve (CN VII)
    • Symptoms: Inability to close the left eye and drooping of the left lip; facial sensation intact, no pain.
    • Explanation: Facial nerve palsy affects CN VII, a mixed nerve. Its motor function innervates facial expression muscles. Its sensory function is responsible for taste from the anterior 2/3rd of the tongue and palate.
    • Associated Factors: Cold exposure, herpes 1 or 2, shingles (herpes zoster), preceding viral infection, stress, neuromas, or other abnormalities.
    • Treatment: PT order and an eye patch.
  • Trigeminal Neuralgia: Trigeminal neuralgia usually involves sudden bursts of pain in face, jaw, or cheek. Muscles of mastication are generally spared and work fine but can bring on an attack.
  • Trochlear Nerve Testing Case
    • Dr. Azzam tests a patient with periodic double vision.
    • Test: Patient turns the right eye inward toward the nose and then attempts to turn the eye downward. The patient is able to look inward but not down. When he looks straight ahead, he is able to look down.
    • Affected Nerve: Trochlear Nerve (CN IV)
    • Explanation: The superior oblique muscle, innervated by the trochlear nerve, lowers the eye when it is turned inward. Thus, testing involves turning the eye to isolate muscle actions.
  • Abducens Nerve Function Confirmation: Dr. Balardi confirms the abducens nerve function by having the patient turn the eye outward (abduction). Abducens nerve innervates the lateral rectus.
  • Trochlear Nerve Integrity Confirmation: Dr. Bell confirms trochlear nerve integrity by starting with the eyes straight ahead, you would have the patient look in and down. Superior oblique-Down and in. Inferior oblique-Up and out

Circle of Willis and Regions of the Brain

  • Cranial Fossa and Brain Locations
    • Anterior cranial fossa
    • Middle cranial fossa
    • Posterior cranial fossa
  • Two Main Arteries Supplying the Circle of Willis (COW)
    • Internal Carotid: Enters the skull through the carotid canal, located in the temporal bone.
    • Vertebral Artery: Enters posterior brain through foramen magnum.
  • Middle Cerebral Artery Stroke Case
    • A 45-year-old male suffers a stroke with paralysis on the right side of his body. CT shows a cerebral arterial hemorrhage has interrupted blood supply to the temporal lobe of the left cerebral hemisphere.
    • Affected Vessel: Middle cerebral artery.
    • Explanation: The middle cerebral artery supplies blood to most of the lateral surface of the cerebral hemispheres and the temporal lobes. Veins drain regions of blood they don’t supply blood to areas. The middle meningeal artery supplies blood to the dura mater and the cranial bone. It does not supply blood to the brain.
  • Arterial Blockage Terminology: This CVA is referred to as ischemic. Ischemia occurs when an artery is blocked –usually by blood clot or plaque.
  • Deficits from Cerebral Vascular Accidents (CVA)
    • Middle Cerebral Artery (MCA) Deficits: Contralateral hemiparesis (weakness) and sensory disturbance of the face, upper and lower extremities (usually more pronounced weakness of the face and arm). There can be expressive aphasia (Broca’s area).
    • Anterior Cerebral Artery (ACA) Deficits: Problems with thought, behavior/personality, and weakness of the opposite leg. The ACA supplies most of the frontal lobes.
    • Posterior Cerebral Artery (PCA) Deficits: Affects many aspects of vision. A right occipital lobe CVA may cause loss of vision to the left side of both eyes. This is called homonymous hemianopsia. However, the same thing can happen with a lesion of the right optic tract.
  • Four Main Regions of the Brain and Primary Function
    • Frontal Lobe: largest anterior: Motor cortex
    • Occipital Lobe: most posterior: visual
    • Temporal Lobe: auditory
    • Parietal Lobe: posterior to frontal: sensory
      • Postcentral Gyrus: lateral parietal lobe, main sensory receptive area for sense of touch.
  • Pterion Bones: Frontal, parietal, sphenoid, and temporal.
  • Epidural Hemorrhage Case
    • A baseball player is hit between the eye and ear (pterion) and immediately loses consciousness.
    • Hemorrhage Type: Epidural.
    • Explanation: An epidural hemorrhage is an accumulation of blood between the dura and the skull.
  • Artery Suspect for Hemorrhage at Pterion: Middle meningeal artery
    • This particular area is at risk as it is the suture of 4 cranial bones: frontal, temporal, parietal, and sphenoid making it a relatively weak point. The middle meningeal artery also lies right behind the pterion making this a clinically significant anatomical location.
    • The meningeal artery supplies the dura and bones of the cranial vault. Its hemorrhage results in compression of the dura mater of the brain, which if not attended to, may result in continued hemorrhaging that would create pressure from blood accumulation.This could result in brain herniation through the tentorium and death.
    • An intracerebral hemorrhage is bleeding within the cerebral hemispheres. A subaponeurotic hemorrhage is under the aponeurosis of the scalp and not clinically significant. A subarachnoid hemorrhage is an acute accumulation of blood between the pia mater and arachnoid mater and usually due to a ruptured aneurysm and/or head injury. A subdural hemorrhage is bleeding under the dura and also caused by head injury.

Dural Folds and Meninges

  • Meningeal Layers of the Brain
    • Dura: The tough outer membrane.
    • Arachnoid: A thin non-vascular membrane which surrounds the brain loosely. The sub-arachnoid space is a real space which contains CSF.
    • Pia: Soft delicate membrane closely applied to the brain tissue. It carries blood vessels which supply the brain with blood.
  • Dural Folds and Location
    • Tentorium Cerebelli: Separates the cerebellum from the occipital poles of the cerebral hemispheres and encloses the transverse sinus. It attaches to the anterior and posterior clinoid processes.
    • Falx Cerebelli: Relatively small, it lies between the 2 cerebellar hemispheres in the median plane. It is attached to the internal occipital crest and superiorly to the inferior aspect of the tentorium. It contains the occipital sinus.
    • Falx Cerebri: A sickle-shaped membrane lying medially between the 2 cerebral hemispheres. Anteriorly it attaches to the crista galli of the ethmoid bone. Posteriorly it is fused with the tentorium.
  • Spinal Cord
    • The spinal cord is a portion of the central nervous system (CNS) enclosed by 3 layers of coverings (just like the brain) lying in the vertebral canal. The spinal cord is approximately 45\,\text{cm}. long and continuous with the medulla oblongata at the foramen magnum
    • The spinal cord terminates inferiorly as the tapered conus medullaris at the L1-2 vertebral level. At birth it lies at L3.

Muscles of Facial Expression and Mastication

  • Nerve Responsible for Facial Expression: Facial Nerve, CN VII
  • Nerve Responsible for Sensation to the Face: Trigeminal Nerve, CN V
    • Innervation for the forehead and eye (ophthalmic V1), cheek (maxillary V2), and lower face and jaw (mandibular V3)
  • Muscles of Facial Expression
    *Occipitiofrontalis: “Say what” VII
    *Corrugator Supercilli: “The Rock” VII
    *Procerus + transverse part of nasalis: Smells terrible/horrible VII
    *Orbicularis oculi: Close eye/Wink VII
    *Levator labii superioris alaeque nasi + alar part of nasalis: Nasal Flaring VII
    *Buccinator + orbicularis oris : Blow Fish/Louis Armstrong VII
    *Zygomatic major + minor: “Grime Face” VII
    *Risorius : Smile VII
    *Risorius + depressor labii inferioris: Jim Carey Ace Ventura/Me Myself & Irene VII
    *Levator labii superioris + depressor labii: Growl/Tiger VII
    *Dilators of mouth: Risorius +Levator labii superioris, depressor labii inferioris: Cheesy Smile VII
    *Orbicularis Oris : Kiss or Smooch VII
    *Depressor Anguli oris : Frown VII
    *Mentalis : Pouting VII
    *Platysma: Scary Face VII
  • Muscles of Mastication: Temporalis, Masseter, Lateral and Medial Pterygoid
  • Nerve Responsible for Mastication: Trigeminal CN V3
  • Nerve Innervating Levator Palpebrae Superioris: CN III Oculomotor
  • Bell’s Palsy: CN VII Facial nerve palsy. Loss of muscles of facial expression on affected side. The person will have drooping on that side of the face.
  • Trigeminal Neuralgia: CN V Trigeminal Nerve compression causes bouts of severe pain to the sensory area of the division that is affected.
  • Pain Sensation from Forehead Injury: the correct answer is: B. ophthalmic V1
    • The ophthalmic division of the trigeminal nerve (CN V) provides sensation to the skin over the forehead in this area. The maxillary division V2 of CN V provides sensory info the maxilla area—nose, cheek, lower eyelid, upper lip). The mandibular division V3 of CN V provides sensation over the skin of the lower jaw (mandible), lower lip, and chin. The facial nerve (CN VII) is mostly a motor nerve of facial muscle although it does provide sensory afferent info by supplying taste from the anterior 2/3rds of the tongue.
  • Muscles Temporarily Paralyzed After Dental Procedure: The correct answer is: C. Zygomaticus major
    • Although more than one muscle can be temporarily paralyzed from a dental lidocaine injection, the only muscle in the list that can raise the lip is zygomaticus major. Procerus wrinkles the skin over the nose. Obicularis oculi closes the eyelids (wink or blink). Mentalis protrudes the lower lip.
  • Muscle Responsible for Food Getting Stuck in Cheek: Correct answer is: C. Buccinator
    • Although buccinators is a muscle of facial expression, it is also supports the mechanical digestion of food in the mouth, so is often discussed with the muscles of mastication. It keeps the check taut while chewing. When this muscle is injured, the check fails to press against the teeth allowing food to fall between the molars and the cheek. Zygomatic major elevates and draws the corners of the lip laterally and up. Orbicularis Oris purses the lips. Levator Labii superioris elevates the upper lip.
  • Temporomandibular Joint (TMJ) Hinge Movements: The correct answer is: A. Condyle/Head of the mandible, disk, and mandibular fossa & articular eminence of the temporal bone.
    • The TMJ joint is a modified hinge synovial joint with an articular disk between the condylar process of and mandibular fossa & articular eminence of the temporal bone of the temporal bone. The zygomatic arch is formed by the zygomatic process of the temporal bone and the temporal process of the zygomatic bone. It forms the prominence of the check. The maxilla is a fixed bone that forms the upper jaw and is just below the nose.
  • Muscle Helping with Opening the Mouth: The correct answer is: A. Lateral pterygoids.
    • The lateral pterygoids can act bilaterally to open the mouth and protrude the chin. Acting unilaterally, it can swing the contralateral side of the mandible producing larger chewing motions. The temporalis elevates (closes) the mandible/chin and is also a primary retractor. The medial pterygoid elevates (closes) the mandible and also produces small lateral motions. It also can contribute to protrusion. The take-away , here, is that most of the muscles about the jaw, close the jaw- except the lateral pterygoids. Opening is also produced by suprahyoid and infrahyoid muscles (the strap muscles) from the anterior neck. ☺ and gravity.
  • Muscle Affected by TMJ Inflammation: The correct answer is: C. lateral pterygoids.
    • The inferior head of the lateral pterygoids inserts into the neck of the mandible, while the superior head inserts directly into the capsule and articular disk! This might cause painful and weakened opening. Temporalis elevates and retracts.. it inserts coronoid process of the mandible and anterior ramus of the mandible. The medial pterygoids protracts and elevates. It inserts on the medial ramus and angle of the mandible. The masseter is a powerful elevator of the mandible. It inserts on the lower half of the ramus. None of these muscles are inserting into the TMJ, so they would not be as affected.
  • TMJ Capsule: The TMJ is a joint that has a capsule strengthened by ligaments on its lateral side only. True or False The Answer is True!

Upper GI

  • Role of the Lower Esophageal Sphincter (LES)
    • The lower esophageal sphincter is a bundle of muscles at the low end of the esophagus, where it meets the stomach. When the LES is closed, it prevents acid and stomach contents from traveling backwards from the stomach.
  • Epithelium of Esophagus and Stomach
    • Esophagus = stratified squamous cells: protection against abrasion, wear and tear (Protect and Transport)
    • Stomach = secretory cell columns: secrete fluids such as acids and enzymes (Digest)
  • Portal Triad: Bile duct, hepatic artery, portal vein Associated with the liver
  • Functions of the Liver
    *Function of the liver is to filter the blood coming from the digestive tract, before passing it to the rest of the body. The liver also detoxifies chemicals and metabolizes drugs. As it does so, the liver secretes bile that ends up back in the intestines.

Lower GI

  • Types of Movement in the Small Intestine
    • During peristalsis, the longitudinal muscles within the small intestine wall contract, and then the circular muscles contract, pushing the food down the tract. This coordinated contraction of smooth muscle keeps food moving on its one-way path through your digestive system.
  • Absorption: Absorption is the act of taking up or in by specific chemical or molecular action; especially the passage of liquids or other substances through a surface of the body into body fluids and tissues, as in the absorption of the end products of digestion into the villi that line the intestine.
  • Routes of Absorbed Nutrients to the Liver
    • Oxygenated blood flows into the liver through the hepatic artery. Nutrient-rich blood flows into the liver from the intestines through the hepatic portal vein.
  • Principle Regions of the Large Intestine
    *In mammals, the colon consists of six sections: the cecum plus the ascending colon, the transverse colon, the descending colon, the sigmoid colon, and the rectum. Sections of the colon are: The ascending colon including the cecum and appendix. The transverse colon including the colic flexures and transverse mesocolon.

GI Clinical Questions

  • Hernia Assessment Case
    • A patient reports pain in his left groin/abdomen after lifting furniture, inability to lift without pain, pain with coughing, and a protuberance above the inguinal ligament.
    • Suspected Condition: Indirect hernia
    • Explanation: Technically, an indirect hernia leaves the abdominal cavity LATERAL to the inferior epigastric vessels enters the inguinal canal through the deep inguinal ring. Commonly, they travel the entire length of the inguinal canal and enter the scrotum (or labia). They usually occur with lifting and mostly in males. A direct hernia leaves the abdominal cavity MEDIAL to the inferior epigastric vessels. They rarely traverse the entire inguinal canal and rarely pass into the scrotum…BUT they can. You would be unable to confirm if the hernia passed medial or lateral to the inferior epigastric vessels to ascertain which type of hernia it is. Because he noted it as something new with lifting, is male, and it is more common, it is more likely that it is an indirect hernia. A femoral hernia is caused by abdominal viscera pushing through the femoral ring into the femoral canal. An incisional hernia occurs after surgery, when the omentum or an organ protrudes through a surgical incision.
  • Appendicitis Assessment Case
    • A patient with chills and pain around her bellybutton is assessed, and tenderness is found 1/3rd the distance from the R ASIS to the navel.
    • Area: McBurney’s point
    • Condition: Appendicitis
    • Why: This is the approximate location of the base of the appendix as it attaches to the cecum
  • Fractured Ribs and Organ Risk: In the left 9th and 10th ribs are fractured, the correct answer is: D spleen
    • The spleen is behind the left 9-11th ribs and rarely extends below the rib cage unless it is swollen. The spleen can bleed profusely and is an emergency situation. Damage to it can also occur from sudden increases in intra-abdominal pressure. The descending colon, left kidney, tail of the pancreas, and stomach are all in the left quadrant, but because of the spleens position close to the ribs, it is at greatest risk.
  • Post-Operative Patient with GI Symptoms:
    • A post-total knee replacement patient reports vomiting, lack of appetite, inability to tolerate pain meds, no bowel movement, bloating, abdominal pain, nausea, and weakness.
    • Action: Urge the patient to contact his physician immediately and follow up to confirm the call. Notify the orthopedic surgeon’s nurse or PA about the situation, missed PT visits, and recommendation. This could indicate a small bowel obstruction. Knowledge about the GI tract is necessary!