Podcast
Questions and Answers
What is the primary function of the pectoral muscles?
What is the primary function of the pectoral muscles?
Which nerve is responsible for innervating the anterior arm muscles?
Which nerve is responsible for innervating the anterior arm muscles?
Which of the following statements about flexion and extension is correct?
Which of the following statements about flexion and extension is correct?
Which nerve provides sensory innervation to the posterior upper limb?
Which nerve provides sensory innervation to the posterior upper limb?
Signup and view all the answers
Which muscles are primarily responsible for elbow extension?
Which muscles are primarily responsible for elbow extension?
Signup and view all the answers
What is the role of the musculocutaneous nerve in cutaneous sensory innervation?
What is the role of the musculocutaneous nerve in cutaneous sensory innervation?
Signup and view all the answers
Which of the following statements is true regarding peripheral nerves?
Which of the following statements is true regarding peripheral nerves?
Signup and view all the answers
Which nerve innervates the flexor compartment of the forearm?
Which nerve innervates the flexor compartment of the forearm?
Signup and view all the answers
What type of reflex occurs when both the quadriceps and hamstrings are involved?
What type of reflex occurs when both the quadriceps and hamstrings are involved?
Signup and view all the answers
Which part of the spinal cord is primarily associated with sensory functions?
Which part of the spinal cord is primarily associated with sensory functions?
Signup and view all the answers
The term 'plexus' refers to what in the context of the spinal cord?
The term 'plexus' refers to what in the context of the spinal cord?
Signup and view all the answers
What is the main function of the white matter in the spinal cord?
What is the main function of the white matter in the spinal cord?
Signup and view all the answers
Which component of the spinal cord contains neuron cell bodies?
Which component of the spinal cord contains neuron cell bodies?
Signup and view all the answers
The ventral rami are responsible for innervating which part of the body?
The ventral rami are responsible for innervating which part of the body?
Signup and view all the answers
Which structure is primarily responsible for carrying sensory information towards the spinal cord?
Which structure is primarily responsible for carrying sensory information towards the spinal cord?
Signup and view all the answers
What type of information does the corticospinal tract primarily carry?
What type of information does the corticospinal tract primarily carry?
Signup and view all the answers
What is the role of the brachial plexus in the human body?
What is the role of the brachial plexus in the human body?
Signup and view all the answers
Which pathway is associated with the sensation of pain and temperature?
Which pathway is associated with the sensation of pain and temperature?
Signup and view all the answers
What does the cerebellum primarily modulate?
What does the cerebellum primarily modulate?
Signup and view all the answers
How many neurons are involved in the ascending sensory pathway?
How many neurons are involved in the ascending sensory pathway?
Signup and view all the answers
What role do endogenous endorphins play in pain control?
What role do endogenous endorphins play in pain control?
Signup and view all the answers
Which type of tract is responsible for descending motor signals to the head and neck?
Which type of tract is responsible for descending motor signals to the head and neck?
Signup and view all the answers
What is the spinal cord's role in reflexes?
What is the spinal cord's role in reflexes?
Signup and view all the answers
Which type of pain relief method is categorized as exogenous?
Which type of pain relief method is categorized as exogenous?
Signup and view all the answers
What is the function of the dorsal rami?
What is the function of the dorsal rami?
Signup and view all the answers
Which region of the spinal cord has the lateral horn carrying sympathetic information?
Which region of the spinal cord has the lateral horn carrying sympathetic information?
Signup and view all the answers
What does the term 'conus medullaris' refer to?
What does the term 'conus medullaris' refer to?
Signup and view all the answers
Which spinal nerves contribute to the formation of the brachial plexus?
Which spinal nerves contribute to the formation of the brachial plexus?
Signup and view all the answers
How many pairs of spinal nerves are total in the spinal cord?
How many pairs of spinal nerves are total in the spinal cord?
Signup and view all the answers
What type of fibers travel through the ventral root of a spinal nerve?
What type of fibers travel through the ventral root of a spinal nerve?
Signup and view all the answers
In which spinal region is there a notable increase in gray matter due to plexus formation?
In which spinal region is there a notable increase in gray matter due to plexus formation?
Signup and view all the answers
Which structure acts to protect the spinal cord?
Which structure acts to protect the spinal cord?
Signup and view all the answers
The sensory information travels to the brain via which root?
The sensory information travels to the brain via which root?
Signup and view all the answers
What is the primary function of the brachial plexus?
What is the primary function of the brachial plexus?
Signup and view all the answers
The sympathetic fibers are primarily associated with which spinal level?
The sympathetic fibers are primarily associated with which spinal level?
Signup and view all the answers
What type of neurons does the ventral horn of the spinal cord primarily contain?
What type of neurons does the ventral horn of the spinal cord primarily contain?
Signup and view all the answers
What mnemonic is used to remember the organization of the brachial plexus?
What mnemonic is used to remember the organization of the brachial plexus?
Signup and view all the answers
Study Notes
Neuroanatomy and A&P
- Dr. Danielle Brewer-Deluce, PhD, is the Assistant Professor
- She teaches the Anatomy Education Program at McMaster
- Contact: [email protected]
PNS Lesions
- Identify the lost information (sensory/motor)
- Determine the affected body region (ventral/dorsal)
- Lesion indicators are provided for specific sites: A-E.
PNS & Plexuses
- Illustrated diagram of PNS and associated plexuses (slide 3)
Motor System (Simplified)
- Corticospinal Tract sends information from the brain to the body.
- The cerebral cortex, thalamus, brainstem, and cerebellum are part of the motor system.
- Basal Ganglia acts as a centralized program that calls motor subroutines.
- Cerebellum modulates motor plans based on sensory input [vestibular, visual and proprioceptive]
Motor vs Sensory Tracts
- Motor: Descending two-neuron path (brain to spinal cord).
- Corticobulbar (head and neck) and corticospinal (lateral + anterior) are two motor pathways
- Sensory: Ascending three-neuron path (spinal cord to brain).
- Spinothalamic (pain and temperature) and DCML (touch, pressure, proprioception) are sensory pathways
Pain Control
- Endogenous pain control:
- Spinal cord gate
- Reticular Formation Activation (endorphins).
- Exogenous pain control:
- NSAIDs & Opiates
Spinal Cord Reflexes
- The spinal cord integrates reflexes, which are fast, involuntary, and unplanned responses to stimuli.
- The patellar tendon reflex illustrates a monosynaptic reflex (Quad → Quad), and a polysynaptic reflex (Quad → Hamstrings) involves an interneuron.
Spinal Cord Purpose
- Solidify understanding of spinal cord anatomy
- Bridge the gap between neurology and musculoskeletal (MSK) systems
Learning Outcomes
- Describe how the central nervous system (CNS) and peripheral nervous system (PNS) interface at the spinal cord.
- Label specific anatomical components of the spinal cord and nerves.
- Define the term "plexus," and explain its structure and functional significance.
- Understand the brachial plexus, its structure, and role in the upper limb.
- Draw and label a brachial plexus diagram
- Hypothesize implications of lesions in different sites within the plexus.
Spinal Cord
- White Matter:
- Peripheral; Longitudinal tracts of axons conveying sensory information to/from the brain, and motor information from/to the brain.
- Gray Matter:
- Central "H" shaped structure. Contains neuron cell bodies, glial cell bodies, and dorsal (sensory) & ventral (motor) horns.
Spinal Cord & Nerves
- Details about structure and content of the spinal cord and spinal nerves. Specific anatomical components, including ventral root, dorsal root, spinal nerve, dorsal/ventral rami, etc are illustrated and labeled.
Spinal Rami
- Dorsal (posterior) Rami: Deep back muscles and Zygapophyseal Joints
- Ventral (anterior) Rami: Everything else
Spinal Nerves are Mixed
- The structure and autonomic characteristics (sympathetic, parasympathetic) of the spinal nerves are described. Information about percentage breakdown of axons for sensory, autonomic, and motor function is included
Spinal Cord in Situ
- Spinal cord is shorter than the vertebral canal
- Spinal cord ends at conus medullaris (vertebral level L2).
- Nerve roots extend further via cauda equina
Spinal Column + Nerves
- Correlation between column vertebrae and corresponding nerve pairs.
Spinal Nerve Naming
- Cervical nerves are named according to the vertebra above them.
- Thoracic/Lumbar nerves are named according to the vertebra they exit from.
Dermatomes
- Spinal levels that supply specific areas of skin (sensory innervation).
- Corresponding plexuses (brachial, thoracic, lumbar, sacral) are linked to their associated spinal levels
Plexuses
- Summary of the topic.
Plexus & Peripheral Nerves
- Anterior Rami merge to form plexus (complex network)
- Multisegmental nerves from other side of plexus (cervical, brachial, lumbar, sacral)
Major Plexuses
- Description and location of major plexuses (cervical, brachial, and lumbosacral) and their innervation zones
Spinal Cord (White and Grey Matter)
- Descriptions of the White and Gray matter of the spinal cord, and why they are important.
To Summarize
- The spinal cord is the center of sensory and motor pathways.
- Motor info travels from the brain to the periphery via the anterior root.
- Sensory info originates from the periphery to the brain via the dorsal root.
- Spinal nerves develop into plexuses, which are combined spinal nerves that innervate peripheral nerves
- Spinal cord ends at L2 level in conus medullaris, and the continuing spinal nerves extend to form the cauda equina
To Summarize (Slide 31)
- Diagram depicting the different parts of the spinal cord, and the related spinal nerves.
- Includes relevant anatomical structures.
Brachial Plexus
- Anterior rami from C5-T1 join to form.
- Clinically important for diagnosing shoulder and upper limb injuries
- 5 key portions for brachial plexus description (roots, trunks, divisions, cords, and branches). Mnemonic "Really Thirsty, Drink Cold Beer!."
Brachial Plexus (Slide 34)
- Illustrates how trunks form at the brachial plexus.
- Sections include descriptions of divisions, cords, and branches and their relevant arteries and nerves
Brachial Plexus (Slide 35)
- Illustrates branches (peripheral nerves) of a brachial plexus. Includes important peripheral nerves like Axillary, Radial, Musculocutaneous, Median, and Ulnar, and their functions. Mnemonic "Really Thirsty, Drink Cold Beer!"
Brachial Plexus (Slide 37)
- Roots, trunks, divisions, and cords are shown branched out from the brachial plexus structure showing their branching order
Brachial Plexus (Slide 38 & 39)
- Detailed diagrams of the brachial plexus branching illustrating the origin, and innervation (path) of the important peripheral nerves
Divisions of Flexion/Extension
- Flexion decreases the angle between bones at a joint.
- Extension increases the angle between bones at a joint.
Extensor Compartment Nerves
- Description and location of extensor compartment nerves in the shoulder and upper limb
Flexor Compartment Nerves
- Descriptions on the location and functions of flexor nerve compartments related to the anterior arm
Cutaneous Sensory Innervation
- Sensory innervation patterns of the brachial plexus nerves. Displayed in diagrams/illustrations for the Musculocutaneous, Median, Ulnar, Radial, and Axillary nerves
Peripheral vs Spinal Nerves
- Illustration of peripheral vs spinal nerve innervation to upper limb. Emphasizes differences in origin of dermatomes (UMN) in comparison to peripheral cutaneous nerves (LMN).
- Shows the overlap of sensory/motor innervation by various nerves.
Where's the Impairment?
- Table illustrates the possible effects of lesions affecting certain nerve roots and trunks of a brachial plexus.
Brachial Plexus
- Brachial plexus provides sensory + motor innervation to upper limb
- 5 spinal nerves (C5-T1) create multi-segmental peripheral nerves (radial, axillary, musculocutaneous, ulnar, median)
- Peripheral nerves innervate specific muscle compartments and skin regions in the upper limb.
- Dermatomes/Myotomes (UMN) originate at specific spinal levels.
Paralysis vs Paresis
- Paralysis = total loss of motor function.
- Paresis = partial loss of motor function.
- Sensory information is lost similarly in paralysis and paresis as spinal nerves are mixed
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the primary functions of muscles and the peripheral nervous system. This quiz covers important topics related to pectoral muscles, innervation, reflexes, and spinal cord functions. Determine how well you understand the anatomy and physiology behind movement and sensation.
