ONE 1 Session 1 PDF

ONE 1 Session 1  Session 1 Outline Course Introduction Nervous System Review Blood Supply Arterial Occlusions Venous Drainage Cerebrospinal Fluid Lab: Vertebrobasilar Insufficiency Tests 2  Course Introduction Orth...

ONE 1 Session 1  Session 1 Outline Course Introduction Nervous System Review Blood Supply Arterial Occlusions Venous Drainage Cerebrospinal Fluid Lab: Vertebrobasilar Insufficiency Tests 2  Course Introduction Orthopedics: concerned with the correction or prevention of issues related to the skeleton and associated structures (such as tendons and ligaments) Neurology: pertaining to the structure, function and diseases of the nervous system Biomechanics: focus on the mechanics of muscular activity 3  Course Introduction Why study orthopedics, neurology and biomechanics? How can we use the information? How do we relate this to TCM? 4  Nervous System Review Basic CNS/PNS structures related to neurology Basal Nuclei (Basal Ganglia) - CNS Diencephalon - CNS Brain Stem - CNS Cerebellum - CNS Spinal Cord - CNS Cranial Nerves - PNS Peripheral Nerves - PNS Spinal cord, cranial & peripheral nerves will be covered in upcoming weeks 5 Basal Nuclei (Basal Ganglia) Structures: Caudate nucleus Putamen Globus pallidus (Substantia nigra) 6  Basal Nuclei (Basal Ganglia) Primary function is motor control Particularly important for starting, stopping and monitoring the intensity of movements Also plays a role with cognition and emotion Generally, acts as a filter, screening for incorrect or inappropriate responses 7 Diencephalon Structures: Thalamus Hypothalamus Epithalamus 8  Thalamus Gateway for information entering the cerebral cortex Sensory relay center: information is sorted, edited, and sent to the appropriate area Also related to emotions, visceral function and memory 9 Brain Stem Structures: Midbrain Pons Medulla Oblongata 10  Brain Stem 3 main functions: Conducts all sensory & motor information between body and brain Contains 9 of the 12 Cranial Nerve nuclei (CN I & II originate in cerebrum, CN XI originates in cervical spine) Integral in control of cardiovascular & respiratory systems, pain sensitivity control, alertness, awareness, and consciousness 11 Cerebellum 12  Cerebellum Cerebellar peduncles: 3 paired neuronal pathways connecting cerebellum to brain stem Superior Peduncles - connect with midbrain, which communicates with cerebral motor cortex Middle Peduncles - connect from the pons Inferior Peduncles - connect with the medulla 13  Cerebellum Refines motor activity; also influences thinking, language and emotion Ensures that movements are carried out in a smooth, coordinated fashion Maintains posture and muscle tone 14  Blood Supply – Circle of Willis The Circle of Willis is a key structure in the supply of blood to the brain It sits at the base of the brain and is an anastomotic system of arteries 3 arteries enter the circle from the neck 6 exit it to supply the brain with blood 3 connect the others, creating the circle 15  Blood Supply – Circle of Willis Image source: https://en.m.wikipedia.org/wiki/File:Circle_of_Willis_en.svg 16  Blood Supply – Circle of Willis 3 arteries enter the circle from the neck: Vertebral Basilar Artery (VBA) Internal Carotid Artery (ICA) (paired) 17  Blood Supply – Circle of Willis Vertebral Basilar Internal Carotid Artery (VBA) Artery (ICA) Image source: https://en.m.wikipedia.org/wiki/File:Circle_of_Willis_en.svg 18  Blood Supply – Circle of Willis 6 arteries (3 pairs) exit the circle, delivering oxygenated blood to specific areas of the brain: Anterior Cerebral Arteries (ACA) (paired) Middle Cerebral Arteries (MCA) (paired) Posterior Cerebral Arteries (PCA) (paired) 19  Blood Supply – Circle of Willis Middle Cerebral Anterior Artery (MCA) Cerebral Artery (ACA) Posterior Cerebral Artery (PCA) Image source: https://en.m.wikipedia.org/wiki/File:Circle_of_Willis_en.svg 20  Blood Supply – Circle of Willis 3 small communicating, or anastomosing, arteries connect the other arteries to complete the circle: Anterior Communicating Artery (ACOM) Posterior Communicating Arteries (PCOM) (paired) 21  Blood Supply – Circle of Willis Anterior Communicating Artery (ACOM) Posterior Communicating Artery (PCOM) Image source: https://en.m.wikipedia.org/wiki/File:Circle_of_Willis_en.svg 22  Blood Supply – VBA The paired vertebral arteries begin at the subclavian arteries. They travel superiorly through the cervical spine passing through the foramina of the transverse processes of the cervical vertebrae. At about the foramen magnum, the two arteries combine to form the basilar artery. Entire structure is the vertebrobasilar artery (VBA) 23  Blood Supply – VBA The VBA continues to the base of the brain to enter the Circle of Willis. The VBA forms the posterior cerebral arteries (PCAs), which exit the circle. The VBA and PCAs supply blood to the: Brain stem Parts of the thalamus Occipital lobe Cerebellum Temporal lobe 24  Blood Supply – ICA The ICAs are major suppliers of arterial blood to the brain and form a large portion of the Circle of Willis. The ICAs form the anterior and middle cerebral arteries (ACAs and MCAs). The ICA supplies the parts of the brain that are not supplied by the VBA. 25  Blood Supply – ACA, MCA, PCA Anterior Cerebral Artery (ACA) Supplies the portion of the brain that controls the lower body Middle Cerebral Artery (MCA) Supplies the portion of the brain that controls the upper body Posterior Cerebral Artery (PCA) Supplies the occipital lobe, parts of the thalamus and temporal lobe 26  Video Anatomy Zone Circle of Willis http://anatomyzone.com/tutorials/cardiovascular/cir cle-of-willis/ 27  Arterial Occlusion Strokes, aka cerebrovascular accidents (CVAs), are most common cause of neurologic disability in adults and fifth leading cause of death in the U.S. Blockage of an artery is the most common cause of a CVA 28  Arterial Occlusion CVA affecting the ICA would result in: Unilateral blindness Severe contralateral hemiplegia and hemianesthesia Profound aphasia 29  Arterial Occlusion CVA affecting the MCA would result in: Alterations in communication, cognition, mobility and sensation Contralateral homonymous hemianopia Contralateral hemiplegia or hemiparesis, motor and sensory loss, greater in the face and arm than the leg 30  Arterial Occlusion CVA affecting the ACA would result in: Emotional lability Confusion, amnesia, personality changes Urinary incontinence Contralateral hemiplegia or hemiparesis, greater in lower than upper extremities 31  Arterial Occlusion CVA affecting the PCA would result in: Hemianesthesia Contralateral hemiplegia, greater in face and upper extremities than in lower extremities, cerebellar ataxia, tremor Visual loss: homonymous hemianopia, cortical blindness Receptive aphasia Memory deficits 32  Arterial Occlusion CVA affecting the VBA would result in: Transient ischemic attacks (TIAs) Unilateral and bilateral weakness of the extremities; upper motor neuron weakness involving face, tongue and throat; loss of vibratory, two-point discrimination and position sense Diplopia, homonymous hemianopia Nausea, vertigo, tinnitus and syncope Dysphagia Dysarthria 33  Arterial Occlusion Complete blockage of VBA would result in: Coma Miotic pupils Decerebrate rigidity Respiratory and circulatory abnormalities Death 34  Video Ted talk Jill Bolte Taylor: My stroke of insight https://www.ted.com/talks/jill_bolte_taylor_my_st roke_of_insight?subtitle=en 35  Venous Drainage Blood drains through the dural venous sinuses, a series of sinuses which lie between the layers of the dura mater Superior Sagittal Sinus Drains blood from the top of the brain Inferior Sagittal Sinus Drains blood from the inside of the brain Cavernous Sinus Drains blood from the face and eyes Transverse Sinus All other sinuses connect with the transverse sinus Empties into the internal jugular vein 36 Dural Venous Sinuses 37  Cerebrospinal Fluid CSF surrounds the brain and spinal cord, providing cushioning and support for these structures CSF is made by choroid plexuses, which are found in the ventricles of the brain CSF is eventually reabsorbed by the arachnoid villi within the dural venous sinuses 38  Cerebrospinal Fluid CSF is a clear and colorless fluid that is similar in composition to blood plasma It contains small amounts of protein, glucose and various ions, such as Na+ and Cl- There are normally zero or very few white blood cells and zero red blood cells in CSF 39  Hydrocephalus There is approximately 150ml of CSF in an adult About 500ml per day is made Normally, CSF is reabsorbed into the blood at the same rate; if there is a blockage or problem, such as a tumor, infection, or hemorrhage, the fluid will build up, leading to hydrocephalus 40  Hydrocephalus In very young children, enlargement of the skull is seen because the cranial bones have not yet formed cranial sutures In adults, hydrocephalus leads to increased intracranial pressure 41  Increased Intracranial Pressure Sx: Exploding headaches Projectile vomiting Ataxia Loss of vision Seizures Eventually, brain stem and cerebellum are forced through the foramen magnum, leading to death 42 Lab: Vertebrobasilar Insufficiency The following test for sufficient blood flow in the vertebral arteries George’s Test Hautant’s Test 43  George’s Test Patient position: seated, neck rotated & extended Instruct patient to look at a stationary object in their lateral vision; hold for 20-30 seconds Ask patient if they experience: Dizziness/light-headedness Visual disturbance Nausea Headache Observe for nystagmus A positive response = vascular impairment Repeat on other side 44  Hautant’s Patient position: seated, arms extended to shoulder level, elbows extended, palms up Part 1: Instruct patient to close eyes and hold position for 20-30 seconds Observe for loss of arm position Positive response to Part 1 = neurological issue; do NOT do Part 2 Part 2: (only if Part 1 is clear) Instruct patient to extend & rotate their neck, holding the same position with eyes closed for 20-30 seconds Observe for loss of arm position Repeat on other side Positive response to Part 2 = vascular impairment 45  Session 2 Outline Quiz: due online prior to next class Spinal Cord Review Spinal Columns and Tracts Upper and Lower Motor Neurons Lab: Pathological Reflexes Start getting kit; need scraping tool, e.g., Taylor style reflex hammer, for next week Sources (unless otherwise noted): Magee, D. J. (2021). Orthopedic physical assessment (7th ed.). St. Louis, MO: Elsevier, Inc.; Marieb, E.N., & Hoehn, K. (2019). Human anatomy & physiology (11th ed.). San Francisco, CA: Pearson Education. 46