Neuroanatomy 1 PDF
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Omar Del Castillo
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This document appears to be notes on neuroanatomy, covering topics such as spinal nerves, cranial nerves, and related concepts. It primarily focuses on different types of nervous system components.
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what SCI level for - Above | SDJF Compilation...
what SCI level for - Above | SDJF Compilation artificial ventilator : 24 NEUROANATOMY 1 Part of the brain : Mr. Omar Del Castillo, PTRP children Upper plexus palsy in ERBs = > - Cerebellum Klumpkies Spinal CN Nuclei ★ Cerebrum Lower plexos palsy = ~ 3I - Nervous System LMNL Nerves o 10 – Dorsal Motor Nucleus / Dorsal Vagal Nucleus - Brainstem Cranial ▪ Innervates heart, lungs, GIT Nerves 12 ▪ Longest CN UMNL CNS PNS PNS o 9 – Inferior Salivatory Nucleus 4 plexus Use of Universal Cuff , except : 24 Plexuses ▪ CN 7 & 9 innervate salivary glands Spinal o 7 – Superior Salivatory Nucleus [code: Sup = Seven] Brain SNS ANS Cord Ganglia o 3 – Edinger Westphal Nucleus LARGEST. each plexus : N CVA-APHASIA ▪ in ↓ - SCI (2CVA) PERRLA [Pupils Equally Round, Reactive TBI Para- to Light & Accommodation]. P C = Phrenic n. = C3 4 5 - = GCS Sympathetic. , , sympathetic MS CN 3 (Oculomotor) Anisocoria pupil RLA-LOCF (diaphragm) CN3 - CP = uneven eye = ★ Light & accommodation reflexes are mediated by - Note: B P =. Radial n Cs-Ti what cranial nerve? CN 3 . =. - Damage to CNS = UMNL; PNS = LMNL (musculospiraln) Pupillary Light Reflex [code: constrict + CN3 → cons-3] Post. ★ board-sensitive: L P Femoral n. Brain - Basic parts of the brain & their clinical correlation - Shine penlight on eyes → eye constricts (post division) =. = 22 3 ,4 - Pupil will regulate amount of light that enters eye, ,. (Ant Crural. n ). (e.g., in aphasia, what part of the brain is affected?) since there’s too much light, it will constrict the eye. P 5. = Sciatic n. = Ly , 5, S1 , 2 , 3 - Blood supply to the structures (Circle of Willis) - If eye does not constrict → affected CN3 Spinal - Tracts: corticospinal, spinothalamic (lateral & Accommodation Reflex Cord anterior), dorsal column pathway - Far object → bring near pt → pupils accommodate Autonomic N.. S = innervated viscera & glands - Clinical correlation: loss of motor, loss of pain & - 3 Cs: temperature, loss of proprioception [SCI] Plexus - Brachial plexus [common in PNI] - Convergence of eyes – d/t (R) & (L) medial recti - Lumbosacral plexus – more of innervations - Constriction of pupil – to focus on object ANS - Sympathetic & parasympathetic responses - Curvature of lens ’s (convexity) - If the 3 Cs are intact → intact reflex → intact CN 3 PNS – 2 main groups: o CN 9 & 7 (Glossopharyngeal & Facial) damaged CN9 Dysphagia Spinal Nerves = 31 pairs drooling of Saliva : ; Excessive 3 Salivary Glands: [innervations ★] · , o Cranial Nerves = 12 pairs Ganglia – collection of nerve cell bodies outside of CNS - Parotid – CN 9 [code: P → 9] o Best example: Dorsal Root Ganglion (DRG) Ist order neuron o Largest, ant to ear o Misnomer: basal ganglia (CNS) o Parotiditis / Parotitis → Mumps ▪ Should be basal nuclei ▪ Seen in Sjogren’s Disease (clinical Nucleus – collection of nerve cell bodies inside CNS triad: dry eyes, dry mouth, RA); PNS – 2 functional subdivisions: dryness of mouth is d/t affected o Autonomic Nervous System (ANS) salivary glands ▪ Innervates visceral organs & glands - Sublingual – CN 7 [code: Sub = Seven] (involuntary) - Submandibular – CN 7 ▪ Organs: heart, GIT ▪ Glands: salivary, sweat glands o Somatic Nervous System (SNS) Sympathetic Nervous System Tietze = costochondritis ▪ Skeletal muscles (voluntary, striated) – o T1 – L3: all 12 thoracic spinal nerves have efferent sympathetic fibers + L1, L2, L3 ▪ Skin – afferent o >L3 = no sympathetic fibers ▪ Joints o Fight or Flight: 3Es Pilatea e ▪ Emergency AUTONOMIC NERVOUS SYSTEM the ▪ Excitement ya Vagal stimulation SYMPATHETIC Thoracolumbar Division PARASYMPATHETIC -constricts Craniosacral Division bronchos ▪ Exercise (most therapist-correlated) o Predominant neurotransmitters used: incision ▪ Epinephrine / Adrenaline Vagotomy openingor of · - ↓HR (T1 – L3) ★ (Cranial Nerves & Sacral Roots) CN 1973 (10 9 7 83) , , ▪ Norepinephrine / Noradrenaline Parasympathetic – “Rest & Digest” , SR: S2-S4 → urinary bladder o Best example (Guyton): when you’re full, you Sympathomimetric “Fight or Flight” Stress “Rest and Digest” [code: rest = Pahinga = Parasympa] feel sleepy [parasympathetic physiologic reaction] or Conservation of energy ▪ Blood rushes where activity is high Emergency situations (sunog) tythic Cholinergic Response 2 ▪ When/after eating → need to digest Adrenergic Response (neurotransmitter: acetylcholine) food → blood will rush to GIT (blood - Adrenaline rush from brain will also rush to GIT) → feels - Neurotransmitter agents used: epinephrine & norepi sleepy bc blood supply to brain is ’d Note: o Which is why when you do ’d physical activity (e.g., basketball, gym) after eating, CN 1973 [code: CN 1973] o 10 – Vagus your stomach will hurt bec the blood o 9 – Glossopharyngeal supposedly intended for GIT goes to your o 7 – Facial exercising muscles → indigestion / dyspepsia o 3 – Oculomotor | SDJF Compilation AUTONOMIC NERVOUS SYSTEM (ANS) (cont.) ★ Pt had a MVA. Pt is in hospital & is constipated. What is the Regulated by hypothalamus ★ reason for the constipation? o Important for homeostasis; temp regulation a. Sympathetic activation 2-Neuron Hook Up b. Parasympathetic activation 1 neuron will synapse with another neuron (2 neurons will Rationale: ’d motility → ’d peristalsis → constipation/NO defecation connect) before reaching & supplying its target organ Organ System Responses (cont.) Sympathetic Parasympathetic BP BP (d/t peripheral vasoconstriction) Bronchospasm Bronchodilation (Bronchoconstriction) Mydriasis / pupillary dilation Miosis / constriction (CN 3) Urine Output [sss] Urine Output [psss] (urinary bladder relaxation + (urinary bladder contraction + sphincter contraction ★) sphincter relaxation ★) Ejaculation [Shoot = Sympa] Erection [Point = Para] PSychogenic Erection ★ Reflexogenic Erection Note: Vasoconstriction → total peripheral resistance (TPR) → BP ★ Sympathetic Parasympathetic ★ NOT all organs vasoconstrict under sympathetic stimulation; - Shorter preganglionic - Longer preganglionic where there is ’d activity in our organs/ms, there we find in - Ganglion farther to - Ganglion closer to blood flow d/t ’d demand (vasodilation) target organ target organ [thus has] o Blood vessels of exercising ms = vasodilate ★ - Diffused response - Localized response o Coronary artery dilation in sympa stimulation ★ - Mass discharge - Neurotransmitters: Bronchodilators = sympathomimetic drug - Neurotransmitters: acetylcholine Sympathomimetic Mimics sympa response Sympatholytic Opposes sympa response 1. Acetylcholine - Cholinergic response 2. Norepinephrine Beta blockers (-olol) = ’s BP = sympatholytic - Adrenergic response Detrusor – ms of urinary bladder Generalization: (Guyton) Erection, 2 types: 1. All preganglionic terminals (both sympa & para) are o Psychogenic erection – fantasize; sympa o Reflexogenic – physical stimulus; parasympa considered cholinergic. 2. All post-ganglionic parasympathetic terminals are Clinical Correlation: considered cholinergic. Horner’s Syndrome 3. Almost all post-ganglionic sympathetic terminals - Primary involves/affects T1 nerve root ★ are considered adrenergic. o T1 has sympathetic fibers - EXCEPT: sweat glands & piloerector ms - (+) Klumpke’s Palsy ★ [they are considered cholinergic bc the o Lower plexus palsy (C8-T1); neurotransmitter used is ACh] ★ o Birth palsy; lower plexus stretched upon delivery ★ Autonomic ganglia is considered cholinergic. - 4 Classic Manifestations: ★ Note: Ptosis d/t Muller’s ms involvement ★ Sympa is activated → acetylcholine (ACh) [lid lag; - part of levator palpebrae (neurotransmitter agent) is released in the drooping of superioris that is responsible for preganglionic terminal to transmit impulse to the post- eyelids] 20% of upper eyelid elevation ganglionic neuron → norepinephrine (NE) is released in - a smooth ms; nerve supply is the the post-ganglionic terminal to transmit impulse to sympathetic nervous system target organ → adrenergic response - 80% is primarily from levator Parasympa is activated → ACh is released in palpebrae superioris (skeletal preganglionic terminal to transmit impulse to post- ms) ganglionic neuron → ACh is released in post-ganglionic Myosis Pupil constriction terminal to transmit impulse to target organ → sympa – responsible for pupil cholinergic response dilation → sympa affected → ORGAN SYSTEM RESPONSES constriction remains/intact Sympathetic Parasympathetic Anhydrosis of Sympa innervates sweat glands → [lahat ng sa heart sympa] half of the face sympa affected → anhydrosis HR SV HR (CN10) Enophthalmos Sunken eyes ★ Heart [vagal stim = mavagal ang HR] CO Force [lahat ng sa tyan para] Peristalsis Motility Peristalsis GIT Digestion ConStipation ★ Gastric Juice Secretion Pancreatic Activity Salivation (CN 7 & 9) | SDJF Compilation SPINAL NERVES Brachial Plexus - Originates from C5-T11 ventral rami ★ Spinal Nerves 31 pairs Review: 5 segments: Gray Matter White Matter Cervical 8 pairs; almost horizontal orientation Brain Outside Inside Thoracic 12 pairs; starts to point downwards Spinal Cord Inside Outside Lumbar 5 pairs; appears more oblique Sacral 5 pairs Coccygeal 1 pair; almost vertical orientation DERMATOME Rationale for orientation: vertebral column is longer than SC A strip of skin innervated by a single root During 3rd month of gestation 28 dermatomes assessed for SCI (ASIA scale) - level of SC & level of vertebral column are equal o NO C1, since C1 has no sensory component ▪ SCI dermatome ax starts at C2 - spinal nerves & exit points are level o NO coccygeal, has sensory root but is no After 3rd month of gestation longer included for SCI ax - faster growth of vertebral column compared to SC o S4-S5 is combined for SCI ax - downward traction of spinal nerves that have previously exited the column. C2 Occiput / external occipital protuberance In SCI, skeletal level is different from neurologic level because C3 Supraclavicular fossa spinal n. are not level with their vertebral column counterparts. C4 On top of acromioclavicular joint C5 Lateral antecubital fossa Landmarks: C6 Thumb ★ Tip of SC Adult: bet. L1-L2 vertebral levels ★ Children: L3 C7 Middle finger [code: SHET-e = 7] If L2 vertebra is fractured in adults, NO part of SC C8 Little finger will be affected bec there is no longer a SC in T1 Medial antecubital fossa that level. If there is damage, the lesion will be in T2 Apex of axilla ★ [code: si T2 may anghit] the spinal nerves, not the SC. ★ T4 Nipple line ★ Lumbar Tap / Spinal Tap / Lumbar Puncture T6 Xiphisternum / xiphoid process - Done in pts c meningitis; CSF sample is extracted T10 Umbilicus ★ to know if there is infection in the brain T12 Inguinal ligament - Best site: L4-L5 ★ L1 Below inguinal ligament Components: L2 Mid-anterior thigh L3 Medial femoral condyle L4 Medial malleolus L5 Dorsum of foot at 3rd MTP ★ S1 Lateral heel ★ S2 Popliteal fossa S3 Ischial tuberosity S4-S5 Perianal area Index finger – C6 ★ Middle finger only – C7 (middle trunk of b. plexus)) Ring finger – C8 Groin – L1 ★ Skin just above knee cap (patella) – L3 ★ - Strip of skin innervated by L3 run from med. femoral Bell Magendie Law, states that condyle to oblique band of skin above the patella - Dorsal part of SC: sensory (afferent) - Ventral part of SC: motor (efferent) *There is NO ventral root ganglion. Dorsal Root Ganglion (DRG) ★ - A unipolar neuron where sensory/afferent fibers pass thru Spinal Nerve (SN) - Formed by the combination of the dorsal root (DR) & ventral root (VR) - Mixed in fxn (has both sensory & motor fxns) - Splits into: dorsal ramus & ventral ramus Dorsal Ramus ★ - Fxn: innervates the skin & ms of the back of trunk Ventral Ramus ★ - Fxn: innervates the skin & ms of ant. trunk & limbs (both UE & LE) MC if cervical = quadriplegia if thoracic = paraplegic | SDJF Compilation TOTAL MUSCLE INDEX SCORE =100 MYOTOME C5 – MC SCI level admitted in hospitals ★ A muscle or group of muscles innervated by a single root C6 – Tenodesis effect ★ [code: tenodeSIX effect] 10 key myotomal levels for ax - Active wrist extension → passive finger flexion o 5 UE - Used to improve pt’s fxn o 5 LE C6 – highest level for indep. sliding board transfer ★ CERVICAL MYOTOMES C8 – highest level that can manage a standard hand C1, C2 Neck Flexors rim w/c (since finger flexors are functional) C3 Neck Lateral Flexors (SCM) [SCM: C2, C3] L3 – critical level for community ambulation in SCI ★ - Primary requirements for community ambulation: C4 SH Shrug (Trapezius) /Also for diaphragm o Both hips should be able to flex UPPER EXTREMITY (hip flexor strength) External Rotators: o At least 1 knee is able to extend for pt C5 SH Abductors (Deltoid) stability Elbow Flexors (Biceps) - Supraspinatus / - Infraspinatus Primary SHER L5 – G.medius - superior gluteal n. (L4, L5, S1) Brachialis ★ To test for S1 neurologic level, what should the pt - Teres minor Scapular Mobilizers: do? Walk on toes (since foot is plantarflexed) DS n. - Rhomboids ★ TRUE about S1 radiculopathy, EXCEPT: ((5) - Downward - Levator Scapulae a. Pt presents c a backward lurch – TRUE rotators tenodesis in C6 Wrist Extensors (ECRL/ECRB) ★ Scapular Mobilizer: To preserve Tenodesis Brachioradialis ★ [C5, C6] - Serratus Ant. WE +FE SCI : Effect SC7 Pronator Teres Elbow Extensors (Triceps) Scapular Mobilizer: SPINAL NERVE EXIT POINTS Sliding EXIT POINTS board Wrist Flexors (FCR, FCU) - Latissimus Dorsi CODES: Finger Extensors (EDC) ★ 1. CERVELOW C8 Finger Flexors (FDS, FDP) FCU, ECU ★ In the cervical area, the name of the nerve that exits has highest SCI level FPL (Ulnar Deviators) the same name as the vertebra below it. that can handle Adductor Pollicis 2. TAASIC [taas + thoracic] standard handrail T1 Finger Abductor (Abd DM) In the thoracic, lumbar & sacral areas, the name of the n. Wheel chair that exits has the same name as the vertebra above it. Interossei PAD-DAB = LOWER EXTREMITY L2 Hip Flexors (Iliopsoas) if Sullivan L2 ↳3 : C1 spinal n. – exits bet. occiput & C1 vertebra Hip Adductors For easier answering (cervical area), Critical level for L3 Knee Extensors (Quads) ★ encircle the 2nd vertebra mentioned. community. amb L4 Ankle DF (Tibialis Anterior) - C1-C2 - L5 Big Toe Extensors (EHL) - C3-C4 ↳ atleast one knee can ext. - C5-C6 S1 Toe Flexors for good prognosis For easier answering (thoracic area), Ankle PF (Gastroc, Soleus) + Ankle Evertors (PL, Pb) encircle the 1st vertebra mentioned. Knee Flexors (Hamstrings) - T1-T2 Hip Extensors (Gluteus Maximus) - T4-T5 Notes: READ SULLIVAN TABLES - T9-T10 Rhomboids (major & minor) & Levator Scapulae are - L4-L5 supplied by the dorsal scapular nerve (C5 n. root only) Sample question in recent boards: ★ C5 can supinate since biceps is already intact T1 spinal n. exits where? Below T1 / Above T2 o Biceps – main supinator of FA C6 can pronate (p. teres) & supinate Serratus Anterior – boxer’s ms o Main action: upward rotation & protraction o Nerve supply: long thoracic n. [code: SALT] ▪ Nerve roots: C5, C6, C7 ▪ C6 – main myotome for S.A. ▪ Involved in medial winging Latissimus dorsi – most important crutch-walking ms o Nerve supply: thoracodorsal n. [CLINICAL CORRELATIONS at next page] ▪ Nerve roots: C6, C7, C8 ▪ N. roots start at C6 [thoracodor6] ▪ C7 – primary root/myotomal lvl Adductor pollicis – ulnar n. (C8, T1) Interossei [code: PAD DAB] o PAD – Palmar Interossei, Adduction o DAB – Dorsal Interossei, Abduction L2, L3, L4, L5 – sipang paharap; S1 – palikod Toe flexion – intact S1; used for sacral sparing signs G. Max – inferior gluteal nerve (L5, S1, S2) primary | SDJF Compilation CLINICAL CORRELATIONS 1. Receptor Muscle spindles Herniated Nucleus Pulposus (HNP) / Slipped Disc 2. Afferent Dorsal root of SC ((5) (+) nerve entrapment 3. Integration Center Inside SC Common involved regions: 4. Efferent Ventral root ((5) 1. Cervical 5. Effector Organ Involved ms - C5-C6 – MC involved level in cervical region If involved ms contracts → (N) reflex response / normoreflexia o Rationale: it is the most mobile segment Note: of the cervical spine, esp in flex & ext Muscle spindles o More mobile → more stress to IV disc → o Intrafusal more probability of acquiring slipped disc o Stretch receptor organs o C6 spinal nerve is impinged o When you tap the tendon, you put a slight Upon MRI, it showed that there is slipped disc between stretch to the ms spindle → it becomes our C5-C6, what manifestation will you expect? receptor a. (–) triceps reflex o That’s why it is called Muscle Stretch Reflex b. Weakness of biceps ms (MSR) bc we are stimulating the stretch c. Paresthesia of thumb receptor organs (ms spindles) d. Paresthesia of little finger Ms spindles Stretch receptor organs 2. Lumbar – more common Senses stretch Tendon Tension receptor organs - L5-S1 Senses tension - L4-L5 Neurologic Levels of DTRs: Posterolateral REFLEXES NEUROLOGIC LEVELS - MC direction of disc herniation in low back Biceps C5, C6 ★ [primary root = C5] ★ Upon MRI, you see a posterolateral herniation bet L5 Brachiorads C5, C6 ★ & S1, what spinal nerve is possibly impinged? Triceps C7, C8 ★ a. L5 Patellar L3, L4 ★ aka “Knee Jerk” b. S1 Achilles S1, S2 ★ aka “Ankle Jerk” Rationale: d/t orientation; in the lumbosacral region, the spinal nerves are ★ A reflex which has a C6 component but is primarily almost vertical such that they exit mediated by C5 – biceps reflex downward & outward. Thus, when it comes to disc herniation bet To elicit brachiorads reflex, tap over the radial styloid L5 & S1, the spinal nerve more likely to be (insertion of brachiorads tendon). impinged is not the one that exits between the segment, but the spinal nerve lower than it (S1). Patellar Reflex Disc herniation bet L4 & L5, what will be compressed? - aka “Knee Jerk” a. L4 - Procedure: leg should be dangled (free to move) b. L5 Rationale: same ratio above applies ADDITIONAL REFLEXES Medial Hams L5, S1 ★ ASSESSMENT Lateral Hams S1, S2 ★ [code: lat. hams is on the SSide] DEEP TENDON REFLEX (DTR) Tibialis Post. L4, L5 aka “Muscle Stretch Reflex” (MSR) Jaw Jerk CN 5 ★ Note: “Myotatic Reflex” Medial Hams – semiten & semimem Monosynaptic reflex responses ★ 2 neurons-monosynaptic o All DTRs are monosynaptic. Thus, when you tap on o Semiten – most prominent tendon at the back of knee G since it's one the landmark, you will immediately get a reflex Lateral hams – biceps femoris connect reaction bc DTRs are monosynaptic. nevron Tibialis Posterior – invertor par excellans ms to another Few examples of polysynaptic reflex: o Tendon is located inside tarsal tunnel neuron - Babinski reflex (medial malleolus; L4 dermatome) - Flexor withdrawal reflex CN 5 – cranial n. responsible for masticatory ms Jaw Jerk, procedure: Significance: to assess the integrity of the reflex arc o Place thumb on chin, below lips o If reflex arc is cut → (–) DTR o Tap over thumb → masticatory ms (temporalis, o UMNL → exaggerated DTR masseter, etc.) are stretched & contracts 5 Components of the Reflex Arc ★ o (+) mouth closes → intact jaw jerk (intact CN 5) 1. Receptor 2. Afferent [sensory component] 3. Integration Center 4. Efferent [motor component] 5. Effector Organ [ms that will contract] Biceps reflex - Use thumb to palpate biceps tendon - Tap on top of thumb → contraction of biceps → intact biceps reflex