Tutorial 5 - Axial Muscles Flashcards
Muscles make up how much of the human body’s weight?
~50%
What are the functions of muscle tissue?
Skeletal Muscles
- move the body by responding to signals from the nervous system
ex: Brachial muscles - flexing
Cardiac Muscles
- responds to involuntary signals from its own conduction system
ex: Heartbeats
Smooth Muscles
- respond to hormones and involuntary signals from the nervous system
- contract and relax to contain substances and move substances through the body
ex: Esophagus - peristalsis
What are the three types of muscles?
- Skeletal muscles
- Cardiac muscles
- Smooth muscles
Skeletal muscles
Attach to bones of the skeleton and contract voluntarily to produce movement
What connects muscles to bones?
Tendons - dense regular connective tissue
What are the 11 regions used to classify muscles of the body?
- Abdomen
- Back
- Head
- Hip
- Gluteal
- Lower limbs
- Upper limbs
- Neck
- Pelvis
- Shoulder girdle
- Thorax
Skeleton: Axial and appendicular
Axial skeleton
- skull/head
- vertebral column
- thoracic cage
Appendicular skeleton (126 bones)
- upper limbs
- lower limbs
- shoulder/pectoral girdle
- pelvic girdle
Head/neck
- aid in swallowing and movements of the head/neck
Suprahyoid muscles:
- digastrics, stylohyoid, mylohyoid, geniohyoid
Infrahyoid muscles :
- omohyoid, sternohyoid, sternothyroid, thyrohyoid
Others:
- anterior/middle/posterior scalene, the splenius, sternocleidomastoid
Shoulder girdle
AKA shoulder joint
- join upper limbs with the axial skeleton
- facilitate the proper rotation of the upper limbs
- coracobrachialis
- pectoralis major
- deltoid (anterior, middle, and posterior heads)
- latissimus dorsi
- teres major
- muscles of the rotator cuff
Back
- paired muscles that act on and support the head, neck, spine, and thoracic cage
- superficial and deep muscles
- deep muscles = intrinsic muscles:
1. erector spinae
2. transversospinalis
3. suboccipital
4. splenius
5. prevertebral
Thorax/Abdomen
- 4 paired muscles
- make up portions of the abdominal wall and act on the abdomen, ribs, and spine
- external oblique
- internal oblique
- transversus abdominis
- rectus abdominis
- pyramidalis
Pelvis/Hip
AKA pelvic diaphragm
- bowl shape to support the reproductive system and parts of the digestive and urinary system
- levator ani
- coccygeus
- iliococcygeus
- internal anal sphincter
- external anal sphincter
- deep transverse perineal
- superficial transverse perineal
- piriformis
- obturator internus
- sacrotuberous ligament
Pelvic diaphragm
muscles of the pelvic floor
Upper limbs
- muscles of the arm
- elbow joint
- forearm
- hand
Lower limbs
- muscles of the thigh (proximal leg)
- leg (distal leg)
- foot
Which three systems interact to produce movement?
Muscular
Nervous
Skeletal
Trace the path from messages to movement
- messages travel through nervous system to skeletal muscles
- motor neurons of the nervous system connect to skeletal muscles via NMJ
- at NMJ neuron releases a neurotransmitter called Acetylcholine
- neurotransmitter binds to receptors on the muscle and begin a chemical reaction within its fibers
- muscle filaments slide across each other and muscles shorten/contract
- movement is produced !
Describe 4 characteristics of skeletal muscles
- striated (actin and myosin)
- motor neurons connect to the skeletal muscle at NMJ
- neurotransmitters are released from motor neuron to skeletal muscle
- excitation (chemical release) and contraction (filaments sliding past each other, muscle shortens and produces movement)
Epimysium
Outer connective tissue layer around a skeletal muscle
Perimysium
Connective tissue layer surrounding fascicles
Endomysium
Connective tissue layer surrounding myofibers
Skeletal Muscle (component breakdown)
Skeletal muscle > fascicles > myofibers > myofibrils
Capillaries and motor neurons
Support myofibers
Myofibrils
thick and thin filaments
Thick filaments
Myosin protein molecules
Thin filaments
actin protein molecules
Sarcomeres
repeating units of thick and thin filaments
Describe the two types of actions in muscle interactions
Paired muscles that perform opposite and opposing actions
- Agonists
- Antagonists
Agonist
generates the main force of an action
- prime mover
- responsible for producing a movement
Antagonist
performs the opposite action
- action opposes agonist
What are the 6 paired actions
flexion - extension
elevation - depression
pronation - supination
flexing - extending
bending - straightening
contracting - relaxing
How are skeletal muscles attached to the skeleton?
via TENDONS
What is the origin on a skeletal muscle
Area where the muscle is attached to 2 articulating bones
- proximal to insertion in anatomical position
- on the fixed bone
What is the insertion point on a skeletal muscle
Area where the muscle is attached to 2 articulating bones
- on the moveable bone
What is the belly or middle of a skeletal muscle
The part of the muscle that shortens
(literally the centre lmfao)
4 Facial Muscles - Eyebrow and scalp
- occipitofrontalis (epicranius)
- corrugator supercilli
- levator palpebrae superioris
- orbicularis oculi
6 Facial Muscles - Upper mouth
- orbicularis oris
- zygomaticus major
- zygomaticus minor
- levator labii superioris
- levator anguli oris
- buccinator
5 Facial Muscles - Lower mouth
- depressor anguli oris
- depressor labii inferioris
- risorius
- mentalis
- platysma
5 Facial Muscles - Mastication (chewing)
- deep masseter
- superficial masseter
- temporalis
- medial pterygoid
- lateral pterygoid
5 Facial Muscles - Tongue
- genioglossus
- hyoglossus
- palatoglossus
- styloglossus
- tongue
Occipitofrontalis (epicranius)
Corrugator supercilli
facial: eyebrow and scalp
move forehead and eyebrows
Levator palpebrae superioris
Orbicularis oculi
facial: eyebrow and scalp
open and close the eyes
Orbicularis oris
facial: upper mouth
purse the lips
Zygomaticus major
Zygomaticus minor
facial: upper mouth
raise corners of the mouth
Levator labii superioris
Levator anguli oris
facial: upper mouth
elevate upper lip
Buccinator
facial: upper mouth
compress cheeks
Depressor anguli oris
Depressor labii inferioris
facial: lower mouth
draw lower lips and corners of mouth down
Risorius
facial: lower mouth
stretches lips laterally
Mentalis
facial: lower mouth
protrudes lower lip
Platysma
facial: lower mouth
depress mandible and tense neck
Deep masseter
Superficial masseter
Temporalis
facial: mastication
elevate mandible during chewing
Medial pterygoid
Lateral pterygoid
facial: mastication
protrude mandible and produces side to side grinding motion
Genioglossus
Hyoglossus
Palatoglossus
Styloglossus
Tongue
protrude, depress, elevate the tongue
What region does “capitis” refer to
neck-ish region
What region does “cervicis” refer to
cervical (neck)
What region does “thoracis” refer to
thorax
What region does “lumborum” refer to
lumbar
Digastric
Stylohyoid
Mylohyoid
Geniohyoid
elevate the hyoid bone and larynx, widening the pharynx and closing off the trachea when swallowing
Omohyoid
Sternohyoid
Sternothyroid
Thyrohyoid
draw the hyoid bone and larynx downward
Sternocleidomastoid
Semispinalis capitis
Splenius capitis
Longissimus capitis
Scalenes
flex and rotate the head and neck
Digastric
neck: suprahyoid
Stylohyoid
neck: suprahyoid
Mylohyoid
neck: suprahyoid
Geniohyoid
neck: suprahyoid
Omohyoid
neck: infrahyoid
Sternohyoid
neck: infrahyoid
Sternothyroid
neck: infrahyoid
Thyrohyoid
neck: infrahyoid
Sternocleidomastoid
neck: head and neck movements
Semispinalis capitis
neck: head and neck movements
Splenius capitis
neck: head and neck movements
Longissimus capitis
neck: head and neck movements
Scalenes
neck
What are the six regions of muscles that make up the vertebral column muscles
- Splenius
- Erector spinae
- Transversospinales
- Segmental
- Scalenes
- Spinal flexors
Splenius (2)
Splenius capitis
Splenius cervicis
Splenius capitis
Splenius cervicis
laterally flex, extend, rotate the neck
What are the three subcategories of erector spinae muscles
- spinalis
- longissimus
- iliocostalis
Erector spinae muscles
superficial back muscles
- prime movers in extension of the vertebral column
Erector spinae: spinalis(2)
spinalis cervicis
spinalis thoracis
- most medial of erector spinae and extend vertebral column
Erector spinae: longissimus (3)
longissimus capitis
longissimus cervicis
longissimus thoracis
- between spinalis and iliocostalis
- extend and laterally flex vertebral column
Erector spinae: iliocostalis (3)
iliocostalis capitis
iliocostalis cervicis
iliocostalis thoracis
- most lateral of erector spinae
- extend and laterally flex the vertebral column
Transversospinales (3)
deep back muscles
- semispinalis
- multifidus
- rotatores
Semispinalis (3)
transversospinales
Semispinalis capitis
Semispinalis cervicis
Semispinalis thoracis
Rotatores (2)
transversospinales
Rotatores breves
Rotatores longi
Multifidus
transversospinales
Segmental (2)
interspinales
intertransversarii
Splenius capitis
vertebral column: splenius
Splenius cervicis
vertebral column: splenius
Spinalis
vertebral column: erector spinae
Longissimus
vertebral column: erector spinae
Iliocostalis
vertebral column: erector spinae
Spinal cervicis
vertebral column: erector spinae
- spinalis
Spinalis thoracis
vertebral column: erector spinae
- spinalis
Longissimus capitis
vertebral column: erector spinae
- longissimus
Longissimus cervicis
vertebral column: erector spinae
- longissimus
Longissimus thoracis
vertebral column: erector spinae
- longissimus
Iliocostalis cervicis
vertebral column: erector spinae
- iliocostalis
Iliocostalis thoracis
vertebral column: erector spinae
- iliocostalis
Iliocostalis lumborum
vertebral column: erector spinae
- iliocostalis
Semispinalis capitis
vertebral column: transversospinales
- semispinalis
Semispinalis cervicis
vertebral column: transversospinales
- semispinalis
Semispinalis thoracis
vertebral column: transversospinales
- semispinalis
Multifidus
vertebral column: transversospinales
Rotatores breves
vertebral column: transversospinales
- rotatores
Rotatores longi
vertebral column: transversospinales
- rotatores
Interspinales
vertebral column: segmental
- extend vertebral column
Intertransversarii
vertebral column: segmental
- laterally flex vertebral column
Scalenes (3)
anterior scalenes
middle scalenes
posterior scalenes
- flex and rotate the neck and elevate 2 ribs during inspiration (breathing)
Anterior scalenes
vertebral column: scalenes
Middle scalenes
vertebral column: scalenes
Posterior scalenes
vertebral column: scalenes
Abdomen (4)
rectus abdominis
external oblique
internal oblique
transverse abdominis
- protect and compress the viscera, aid in forced respiration, and rotate the trunk
Spinal flexors (3)
longus capitis
longus colli
quadratus lumborum
- flex the neck and vertebral column
What is viscera
the internal organs in the main cavities of the body, especially those in the abdomen, e.g. the intestines.
Longus capitis
vertebral column: spinal flexors
Longus colli
vertebral column: spinal flexors
Quadratus lumborum
vertebral column: spinal flexors
Rectus abdominis
abdomen
External oblique
abdomen
Internal oblique
abdomen
Transverse abdominis
abdomen
Pelvis (general - 2)
- levator ani
- coccygeus
The levator ani and coccygeus form the _________________
Pelvic diaphragm
- support the pelvic floor and draw it upward during defecation
Pelvis - superficial perineal (3)
- superficial transverse perineal
- bulbospongiosus
- ischiocavernosus
Pelvis - deep perineal (2)
- deep transverse perineal
- external anal sphincter
levator ani
pelvis
coccygeus
pelvis
superficial transverse perineal
(identify and functions)
pelvis - superficial perineal
- support the central tendon of perineum
bulbospingiosus
ischiocavernosus
(identify and functions)
pelvis - superficial perineal
- maintain erection in the penis or clitoris
deep transverse perineal (identify and functions)
pelvis - deep perineal
- support central tendon in perineum
external anal sphincter (identify and functions)
pelvis - deep perineal
- close the anus
Thorax (3)
- diaphragm
- external intercostals
- internal intercostals
The thorax is involved in ___________
Breathing
Diaphragm
Thorax
- prime mover of inspiration
- dome, thin muscle below lungs and heart
- attached to the sternum
External intercostals
Thorax
- assist in inspiration
Internal intercostals
Thorax
- assist in forced expiration
What are the five types of movement in anatomic position?
Flexion
Extension
Abduction
Adduction
Circumduction
What is flexion
movement in the anterior-posterior sagittal plane
- decreases angle
What is extension
anatomical position is full extension of a muscle
- hypertension is extension beyond the anatomical position
- increases angle
What is abduction
movement AWAY from the longitudinal axis (midline) in the frontal plane
What is adduction
movement TOWARD the longitudinal axis (midline) in the frontal plane
What is circumduction
movement of the arm in a circle but not rotating
Describe flexion and extension
movement at the hinge joints of long bones
- movement of the AXIAL skeleton
Describe abduction and adduction
movement of the APPENDICULAR skeleton
What are the three different types of flexion/extension
lateral flexion - vertebral column bends side to side
dorsiflexion - ankle flexion
plantar flexion - called flexion but is ankle extension
What is hyperextension
extension beyond the anatomical position
What are the two types of rotation
- head and trunk rotation
- limb rotation
What is head and trunk rotation
rotation at the atlanto-axial joint (head and neck) right and left
What is limb rotation
medial or lateral rotation
What is medial rotation
inward rotation
= anterior surface turned towards midline
What is lateral rotation
outward rotation
= anterior surface turned away from midline
What is forearm rotation (2)
pronation and supination
Pronation
turning the palms facing forward in anatomical position to back
Supination
turning the palms from back in anatomical position to forward
What are the five types of special movements?
- opposition
- protraction
- retraction
- inversion
- eversion
Opposition
moving your thumb to touch other digits
Protraction and retraction (Compare and contrast)
protraction = moving forward/anteriorly
retraction = moving backward/posteriorly
ex: jutting the jaw and retracting the jaw
Inversion and eversion (Compare and contrast)
inversion = moving the foot towards the midline
eversion = moving the foot away from the midline
What is an action (origin and insertions)
action = movement produced when a muscle contracts
What is a synergist
- aids agonist
- prevents movement at another joint (fixators)
Anterior
front
External
on the outside
Inferior
below
Internal
away from the surface
Lateral
on the side
Medial
middle
Oblique
slanting
Posterior
back
Rectus
straight
Superficial
toward the surface
Superior
toward the head
Transverse
crosswise
Abductor
movement away
Adductor
movement toward
Depressor
lowering movement
Extensor
straightening movement
Flexor
bending movement
Levator
raising movement
Pronator
turning to prone position
Supinator
turning into supine position
Tensor
tensing movement
What are the four groups of axial muscles
- muscles of the head and neck
- muscles of the vertebral column
- abdomen
- pelvis
Muscles of the head and neck
NOT ASSOCIATED WITH THE VERTEBRAL COLUMN
- facial expression muscles, extrinsic eye muscles, tongue, pharynx, and neck muscles
Muscles of the vertebral column
flex, extend, or rotate the vertebral column
Abdomen
oblique and rectus trunk
Pelvis
pelvic floor, pelvic outlet, and support pelvic organs
What are the four muscles of the tongue
genioglossus
hyoglossus
palatoglossus
styloglossus
What are the three muscles of the pharynx
pharyngeal constrictors
laryngeal elevators
palatal muscles