Tuesday, October 5, 2010
Friday, October 1, 2010
Week 7
Strength of Muscle depends on
# of fasiculi
Arrangement of fasiculi – tendon pattern
Direction of pull
Leverage
Size
# of motor units
Muscle naming
Attachment location
Shape
Division of heads
Action
Size
Origin & insertion points
Facial Muscles
Origin on superficial fascia or underlying skin
Inserts on skin
Cutaneous
7th cranial nerve innervates
Orbicularis Oculi
Circular muscle around the eye
Closes eyelind – wink blink
Corregator
Just above obicularis oculi
Pyramid shaped – frowning muscle
Orbicularis Oris
Circular muscle around the mouth
Kissing muscle
Procerus
Longitudinal muscle
Wrinkles nose or flare nostril
Buccinator
Transverse muscle
Keeps food between teeth – a cheek
Frontalis
Longitudinal muscle
Raises eyebrows
Vertically oriented
Occipitalis
Based on the occipital
Occipitofrontalis
Frontalis + Occipitalis
Galeal aponuerotica lies between them
Mastication Muscles – chewing
4 paired muscles
Temporalis
Radiate
Inserts on mandible
Mandible Sling
Masseter
Inserts on outer Ramus of mandible
Vertical orientation
Power stroke of chewing
Medialpterygoid
Vertical orientation
Inerters on inner Ramus
Lateral Pterygoid
Perpendicular orientation
Can open or protrude jaw
Tounge
Intrinsic
Within the tounge
Speech whistling and can change the shape of the tounge
Extrinsic
Outside the tounge
Lets the tounge move in and out of the mouth
Neck
Platysma
Thin superficial broad sheet that covers lateral side of the neck & shoulder
Inserts on mandible
Contractions pull down corners of mouth
Sternocleidomastoid
Sternum – origin
Clavicle – origin
Mastoid – Insertion
Flexor and extensor
Rectus Abdominus
Spine flexor
Tendonous intersections
Inserts on xiphoid process
Origin on pubic crest
Erector Spinae
Posture muscle
3 columns formed
back extensor
Iliocostalis
Lateral most
Origin at ilium
Insertion along ribs
Longisimus
Intermediate and largest
Inserts on vertebra/ribs
Origin on sacrum
Spinalis
Most medial
Abdomen
3 pair of muscles
rotate spine
compress abdomen
External oblique
Fibers run medial & inferior
Inserts on aponeurosis
Internal oblique
Runs medial & superior
Transverse abdominus
Run medially
Thorax
Internal Intercostal
Fibers run medial & inferior
Only used when needed
Pulls ribs down
External Intercostal
Fibers run superior & medial
Elevates ribs
Used in normal breathing
Diaphragm
Dome Shaped
Originates from the circumference of body
Inserts on its own central tendon
Contractions pull diaphragm down to increase the volume the lungs can use for more air
3 openings
Aortic hiatus
Inferior vena cava
Esophageal hiatus
Trapezious
3 parts
Upper
Middle
Inferior
Inserts on Scapular spine
Originates on occipital
Deltoid
Forms rounded contour of shoulder
Actions shoulder abduction, flexion and extension
Pectoralis Major
Origin Clavicular head & anterior surface of the sternum
Insertion intertubercular groove of the humerus
Flex adduct and rotate humerus
Latisimus Dorsi
Extends humerus adduction
Inserts on humerus
Originates 2 on scapula
Biceps Brachii
Flexor of elbow
Originates on coracoid process
Inserts on radius
Triceps Brachii
Extensor of elbow – biceps antagonist
Inserts on olecranon process
Originates 2 on humerus 1 on scapula
Forearm muscles
A lot
Short version
Anterior side = flexion of wrist carpals & phalanges & supinator
Posterior side = extensor or wrist carpals & phalanges & pronator
Psoas
Hip & spine flexor
Knee extensor
Iliacus
Hip & spine flexor
Knee extensor
Quadriceps Femoris
Rectus Femoris & 3 vasti – lateralus intermedius medialis
Rectus femoris
Originates at ilium
Inserts on knee
Flex hip
Knee extension
The 3 Vasti muscles
Originate on femur
Insert on knee
Knee extension
Sartorius
Allows us to cross legs at the knee
Longest muscle in the body
Flex knee and hip
Gluteus Maximus
Extension & lateral rotation
Hamstring
Biceps femoris
Most lateral
Extends hip
Flex knee
Semi Tendonosis
Middle
Extends hip
Flex knee
Semi Membranosis
Extend hip
Flex knee
Calf or Crural Muscles
Anterior Posterior and Lateral
Tibialis Anterior
Dorsal Flexion
Extends toes
Peronius Longus
Lateral
Plantar Flexion
Inversion of the foot
Gastocnemius
Posterior
Originates on distal end of femur
Inserts on calcanoues
Responsible for push for locomotion
Achilies tendon
Plantarflexion
Flexion of knee
Soleus
Posterior
Inserts beside calcaneous
Plantarflexion
Friday, September 24, 2010
Week 6
Arm 1 bone
Forearm 2 bones
Phalanges 14 bones
Carpals 2 rows of 4 = 8
Metacarpal 5 bones
Humerus
Articulates with glenoid cavity at the proximal end
Articulates with both Radius and Ulna distally
Ulna
Medially fits in olecranon fossa via olecrannon process
Articulates with carpals distally
Radius
lateral side of the elbow to the thumb side of the wrist
articulates with the capitulum of the humerus, the radial notch and the head of the ulna.
Carpals
Proximal Row and laterally
| Scaphoid | Lunate | Triquetrium | Pisiform |
| Trapezium | Trapazoid | Capitulum | Hamate |
Metacarpals
Proximal Row Laterally
| I | II | III | IV | V |
Phalanges
Proximal Middle or Distal
| P | P | P | P | P |
| D | M | M | M | M |
| | D | D | D | D |
Pelvic Girdle
2 innomimal bones
os coxae
cotal bones
Each hip bone has Fused 3 parts
Ilium – Top broad flat part
Ischium – inferior and posterior part
Pubis – Ventral anterior forming pubic arch
Acetabulum
Articulates with femur
Obturator foramen
Filled with connective tissue
Pubic Symphysis
Firm union with hyaline & fibrocartilage
Thigh
Femur
Largest and heaviest bone in the body
Articulates with acetabulum via the trochanter
Distal end expands for articulation with tibia
Has medial and lateral condyles
Tibia
Medial
Weight bearing
Tibial tuberosity
Distally articulates with talus
Fibula
Lateral
Proximal articulation with tibia
Distal articulation with talus
Foot
Calcaneous
Talus
I - II – III cuniforms
Cuboid
Metatarsal medial à lateral
Same name of phalanges
Some distal and middle phalanges have been known to fuse
Patella
Sesamoid
Entirely within a tendon at a point of major pressure
Patellar tendon
Arthrology
3 categories based on movement
Synarthoris à no movement
Amphiarthrosis à some movement
Diarthrosis à freely moveable
3 based on structure
Fibrous à little to no movement
Syndesmosis - more fibrous tissue
Suture - minimal fibrous tissue
Cartilage à litte to no movement
Synchondrosis – temporary growth plate
Symphysis
Synovial à freely moveable
Joint capsule line with synovial membrane for synovial fluid production for lubrication
Synostosis – sutures that have completely calcified
Arthrodia – Gliding joints
Carpal bones
Non axial
The Muscular system
Only Skeletal & voluntary muscles/organs
Maintains posture – due to tonus
Tonus - continuous contraction of muscle
Stabilizes articulations
Red meat of the body
Functions for locomotion
Produces heat
Interdependent system
Contractible irritable extensible elastic
Usually attached to bone
Fatigues Fast
Responds to Stimuli Faster
Less Extensible
Supports Nervous & Vascular system
Muscle movement can act as a pump (especially vascular system – lymph)
Has both Sensory and Motor Neurons
Lots of Mitochondria
Muscle Belly
Fibers & tendon(s)
Tendon of Origin – attaches to less moveable structure
Tendon of Insertion – attaches to more movable structure
May have 2 or more tendons of Origin
May have Single origin and Several insertions
Aponuerosis à broad flat tendonous sheet, mainly serving to connect a muscle with the parts it moves
Deep Fascia
Each fiber has a sarcolemma
Endomycium surrounds sarcolemma
Fasiculus is a bundle of fibers
Perymycium surrounds each fascicle
Epimycium surrounds the all fasicles as a whole
NueroMuscular Junction
Muscles and nerves actually don’t touch
Synaptic bulb is the end of the nerve that begins the synaptic cleft
Synaptic Cleft is just the space between the nerve and the muscle
Motor End Plate is the sarcolemma of the muscle
In the Synaptic Cleft
Several Mitochondria
Several Synaptic vesicles
Containing ACh acetylcholine
ACh causes change in permeability that causes muscles to contract
Or contains AChE acetylcholinesterase
AChE causes change in permeability that causes muscles to relax
By removing ACh
Arrangement
Nuclei lies under the sarcolemma
Myofibril arrangement causes light and dark bands
Also directly responsible for muscle contraction
Actin = thin band
Filaments anchored in Z line
Myosin = Thick band
Filaments anchored near M line
Sarcomere
Distance between 2 adjacent Z lines
I Band – Thin Actin ONLY
H Zone – Thick Myosin ONLY
A Band - location where Actin and Myosin overlap
M Line – Down the middle of thick myosin
Sliding Filament Theory
The sliding filament theory is the explanation for how muscles produce force (or, usually, shorten). It explains that the thick and thin filaments within the sarcomere slide past one another, shortening the entire length of the sarcomere. In order to slide past one another, the myosin heads will interact with the actin filaments and, using ATP, bend to pull past the actin
All or None Law
If the stimulus is any strength above threshold, the nerve or muscle fiber will give a complete response or otherwise no response at all
Motor units
Controls anywhere from 3 – 150 fibers
# of motor units determines Total amount of force used
Roles of Muscle
Prime Mover – Main muscle involved in desired action
Antagonist – Counteracts action of prime mover
Synergist – Steadies movement or removes unwanted movement
Fixator – Maintains same position
Coordination – Cooperation Between muscles
Controlled via cerebellum
A muscle that is closer to a joint has greater range of motion but losses leverage
A muscle that is away from a joint has less range yet more leverage
Muscle Arrangement
Longitudinal (Parallel) all fibers arranged parallel fashion
Can shorten by 1/3 or ½ length of muscle belly
Weak
Unapenate – Muscle fibers attach laterally along 1 side
Bipenate – muscle fibers attach laterally 2 sides – Powerfull
Radiate --Combined arrangement of flat and fusiform
muscles, orginate on brad aponeurosis and
converge onto a tendon
Orbicularis -- a muscle encircling an orifice
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