Axial Musculature System Flashcards
Connective Tissues of a Muscle
What are the 4 layers of CT from deep to superficial?
Endomysium
Perimysium
Epimysium
Fascia(e)
Connective Tissues of a Muscle
Endomysium
thin layer of areolar CT that surrounds each individual muscle fiber
Connective Tissues of a Muscle
Perimysium
wraps muscle fibers together in a bundle called fascicles
Connective Tissues of a Muscle
Epimysium
Surrounds the entire muscle as a tendon, connects muscle to bone
Connective Tissues of a Muscle
Fascia(e)
CT that separates neighboring muscles (wraps muscle group)
Muscle Shapes
Fusiform Muscles
Think in the middle, tapered at ends
(Ex. biceps brachii)
Muscle Shapes
Parallel Muscles
Uniform width, fascicles aligned
(ex. Rectus Abdominis)
Muscle Shapes
Triangular Muscles
Broad at one end, narrow at the other
(ex. Pectoralis Major)
Muscle Shapes
Unipennate Muscles
Muscles whose fibres attach to one side of the tendon
(Ex. Palmar Interosseous)
Muscle Shapes
Bipennate Muscles
Feather shaped muscles
(ex. Rectus Femoris)
Muscle Shapes
Multipennate Muscles
Central tendon branches into multiple rows of muscle fibers
(ex. Deltoid)
Muscle Shapes
Circular Muscles
Form rings around body openings
(ex. Orbicularis Oculi)
Intermuscular Septa
border that separates compartments spaces that are enclosed by fasciae
What is found in each musclar compartment?
One or more functionally related muscles
Nerves and blood vessels
Upper limbs muscle compartments
Anterior and posterior compartments
Lower limbs muscle compartments
Anterior, posterior, medial, and lateral compartments
Directly (fleshly) Attachment
Close muscle association to bone due to collagen fibers
(muscles seem to attach directly to bone)
Indirect Attachment
Tendon attaches muscle to bone
Aponeurosis
muscle is connected to bone using a broad sheet like tendon
Intristic Muscles
Origin and insertion muscles contained within a certain region
(ex. muscles within hand or foot region)
Extrinsic Muscles
Muscles that originate elsewhere but acts in another specific region
(ex. flexion of the digits require muscles in the forearm)
Coordinated Groups of Muscles
Action
Effect produced by a muscle
Produce or prevent movement
Coordinated Groups of Muscles
Prime Mover (agonist)
Muscles that produces main force of action
(ex. brachialis is the prime mover during elbow flexion)
Coordinated Groups of Muscles
Synergist
Muscles that aids prime mover in any way
(ex. directly assisting or stabilizing joints for more coordinated movement)
Coordinated Groups of Muscles
Antagonist
Muscle that opposes prime mover
Anatagistic Pair: muscles that act on opposite sides of joints
Coordinated Groups of Muscles
Fixator
Muscles that prevents bone movement during muscle actions
(Ex. Arm abduction movement will abnormally pop scapula out laterally unless for fixators)
Label the lever (wood), fulcum, effort, and resistance in regards to the body
Lever – bone.
Fulcrum – joint.
Effort – from muscle.
Resistance (load) – object moved.
What is the formula for Mechanical Advantage?
Length of effort arm/Length of Resistance Arm
LoEA/LoRA
What occurs when the Mechanical Advantage is both greater than or lesser than 1?
Greater than 1 MA = high power, low speed
Lesser than 1 MA = low power, high speed
Describe the First Class Lever
Effort Fulcrum Resistance (EFR)
Fulcrum is in the middle
Example is a seasaw or extending neck
Describe the Second Class Lever
Effort Resistance Fulcrum (ERF)
Resistance is in the middle
Ex. Lifting a wheelbarrow
Describe the Third Class Lever
Resistance Effort Fulcrum (REF)
Effort in the middle
Ex. flexing elbow
(most common lever in the body)
How are muscles named?
- Size
- Shape
- Location
- # of heads
- Direction of fibers
- Action
Muscles of the Face
Frontalis
Elevates eyebrows
Muscles of the Face
Orbicularis Oculi
Closes eyes
Muscles of the Face
Orbicularis Oris
Closes lips
Muscles of the Face
Zygomatius Major/Minor
Raises the corner of mouth for smiling
(smiling muscles)
Muscles of the Face
Temporalis and Masseter
Elevate mandible and move it laterally
Neck Muscles
Digastric
Depresses Mandible
Neck Muscles
Sternohyoid
Depresses Hyoid
Neck Muscles
Sternothyroid
Depresses larynx
Neck Muscles
Sternocleidomastoid
Unilaterally active: Rotates head side to side
Bilaterally active: Draws head foward
Neck Muscles
Trapezius
Extends Neck
Diaphragm
Prime mover of inspiration
Rectus Abdominis
Flexes waist
Transverse Abdominal
Compresses abdominal contents
Erector Spinae
Straightens Spine