Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
97 Cards in this Set
- Front
- Back
|
Aggregate muscle action |
muscles work in groups rather than independently to move joints |
|
|
Shape and fiber arrangement affects... |
Muscle's ability to exert force, range through which it can effectively exert force onto the bones |
|
|
Cross section diameter affects... |
Force produced (more diameter = more force exertion) |
|
|
Muscle's ability to shorten affects... |
ROM (longer muscles can shorten more; more effective in moving joints through large ROM) |
|
|
Types of Fiber Arrangements |
Parallel and Pennate |
|
|
Fiber Arrangement: Parallel (5 types) |
Produce a greater range of movementthan pennate arrangement; flat, fusiform, strap, radiate, sphincter/circular |
|
|
Parallel Fibers - Flat |
Thin and broad originating from broad, fobrous, sheet-like aponeuroses Ex: rectus abdominus and external oblique |
|
|
Parallel Muscles - Fusiform |
Spindle-shaped with central belly that tapers to tendons on each end Ex: brachialis, biceps brachii |
|
|
Parallel Muscles - Strap |
More uniform in diameter essentially all fibers arranged in a long parallel manner Ex: Sartorius |
|
|
Parallel Muscles - Radiate |
Triangular, fan-shaped, convergent Combined arrangements of fusiform and flat Originate on broad aponeuroses and converge onto tendon Ex: pec major, trap |
|
|
Parallel Muscles - Sphincter/Circular |
Endless strap muscles Surround openings and close them upon contraction Ex: orbicularis oris surrounding mouth or on eye |
|
|
Fiber Arrangement: Pennate (3 types) |
Shorter fibers than parallel; Arranged obliquely to their tendons similar to a feather; Arrangement increases cross-sectional area, which increases power |
|
|
Pennate Muscles - Unipennate |
Fibers run obliquely from a tendon on one side only Ex: biceps femoris, tibialis posterior |
|
|
Pennate Muscles - Bipennate |
Fibers run obliquely on both sides from central tendon Ex: rectus femoris |
|
|
Pennate Muscles - Multipennate |
Several tendons with fibers running diagonally between them Ex: deltoid Bipennate and Unipennate produce strongest contractions |
|
|
Skeletal Muscle Tissue - 4 Properties |
Irritability/excitability, contractility, extensibility, elasticity |
|
|
Muscle Tissue Properties - Irritability/Excitability |
Muscle being sensitive/responsive to chemical, electrical, or mechanical stimuli |
|
|
Muscle Tissue Properties - Contractility |
Ability to contract and develop tension/internal force against resistance when stimulated |
|
|
Muscle Tissue Properties - Extensibility |
Ability to be passively stretched beyond normal resting length |
|
|
Muscle Tissue Properties - Elasticity |
Ability to return to original length following stretching |
|
|
Muscle Terminology - Intrinsic |
Muscles within or belonging solely to body part upon which they act Ex: small intrinsic muscles in hands or feet |
|
|
Muscle Terminology - Extrinsic |
Muscles that arise or originate outside or proximal to body part upon which they act Ex: forearm muscles that attach proximally on distal humerus and insert on fingers |
|
|
Muscle Terminology - Action |
specific movement resulting from a concentric contraction; usually caused by group of muscles working together |
|
|
Muscle Terminology - Innervation |
segment of nervous system defined as being responsible for providing stimulus to muscle fibers within a specific muscle/portion of muscle; muscle can be innervated by more than one nerve and a nerve may innervate multiple muscles |
|
|
Muscle Terminology - Amplitude |
range of muscle fiber length between maximal and minimal lengthening |
|
|
Muscle Terminology - Gaster (belly or body) |
central, fleshy portion of muscle that increases in diameter as the muscle contracts; contractile portion of muscle |
|
|
Muscle Terminology - Tendon |
fibrous connective tissue that connects muscle to bone; two muscles can share a tendon and a muscle can be connected to multiple tendons |
|
|
Muscle Terminology - Aponeurosis |
Tendinous expansion of dense fibrous connective tissue that's sheet or ribbon-like and resembles a flattened tendon; serve as fascia to bind muscles together or connecting muscle to bone |
|
|
Muscle Terminology - Fascia |
Sheet or band of fibrous connective tissue that envelopes, separates, or binds together parts of the body |
|
|
Muscle Terminology - Origin |
Proximal attachment of a muscle or the part that attaches closest to midline or center of body; least movable part of muscle |
|
|
Muscle Terminology - Insertion |
Distal attachment of a muscle or part that attaches farthest from midline or center of body; most movable part of muscle |
|
|
When a muscle contracts... |
Tends to pull muscle toward the gaster; If neither of the bones are stabilized then they both move toward each other; More commonly one bone is stable while the other is less so and moves toward more stabilized one SOMETIMES REVERSE (pull up where radius stable and scapula moves up) |
|
|
Muscle contractions and what they can be used for (3) |
Tension developed in muscle as result of a stimulus Cause, Control, Prevent |
|
|
Isometric contractions |
Active tension developed but joint angles remain constant; Static contractions; Prevent motion |
|
|
Isotonic contractions |
Active tension to cause or control joint movement; Dynamic contractions; Varying degrees of tension result in joint angles changing; Concentric or eccentric |
|
|
Can movement occur without muscle contraction? |
Yes - passive; due to external forces (other person, gravity, object) |
|
|
Isokinetics |
Dynamic exercise using concentric and/or eccentric muscle contractions; Speed constant, contraction occurs throughout movement; NOT another type of contraction; Ex: Biodex, Cybex |
|
|
Agonist Muscle |
Cause joint motion; primary mover(s) |
|
|
Assisters/Assistant Movers |
Agonist muscles that contribute significantly less to the joint motion |
|
|
Antagonist Muscles |
Opposite side of joint from agonist and have opposite concentric action; AKA contralateral muscles; Cooperate with agonists to relax and allow movement; Ex: quads antagonists to hamstrings in knee flexion |
|
|
Palpation |
Using sense of touch to feel or examine superficial muscle as it contracts |
|
|
Electromyography (EMG) |
Utilizes electrodes placed over or into muscle; Detects action potentials of muscles and provides electronic readout of contraction intensity duration and intensity; Most accurate way of detecting presence and extent of muscle activity |
|
|
Electrical Muscle Stimulation (e-stim) |
Use electricity to cause muscle activity; Electrodes over muscle and stim causes contraction; Joint actions may be observed to see the effect of the contraction |
|
|
Every muscle fiber is innervated by what? |
A somatic motor neuron that results in contraction when stimulated |
|
|
Five levels of control of the CNS |
Cerebral cortex, basal ganglia, cerebellum, brain stem, spinal cord |
|
|
Cerebral cortex |
Highest level of control; Creation of voluntary movement as aggregate muscle action; Interprets sensory stimuli to determine if response needed |
|
|
Basal ganglia |
2nd highest level of control; Controls postures and equilibrium, learned movements, sensory integration for balance and rhythmic activities |
|
|
Cerebellum |
Major integrator of sensory impulses; Provides feedback relative to motion; Controls timing and intensity of muscle activity to assist in the refinement of movements |
|
|
Brain Stem |
Integrates all CNS activity through excitation/inhibition of desired neuromuscular functions; functions in arousal or maintaining a wakeful state |
|
|
Spinal Cord |
Pathway between CNS and PNS; most specific control; integrates simple and complex reflexes; integrates cortical and basal ganglia activity with classifications of spinal reflexes |
|
|
PNS is divided into... |
Sensory and Motor |
|
|
Sensory Division of PNS |
Bring impluses TO CNS |
|
|
Motor Division of PNS |
Carry impulses FROM CNS |
|
|
Efferent nerves divided into... |
Voluntary/somatic - impulses to muscles Involuntary/visceral (AutoNS) - impulses to heart, smooth muscles, glands |
|
|
PNS has what 2 groups of nerves of importance? |
Cranial and Spinal Nerves |
|
|
Cranial Nerves |
12 pair originating from undersurface of brain and exiting from the cranial cavity through skull openings; 1, 2, 7 - sensory 3, 4, 6, 11, 12 - motor 5, 7, 9, 10 - both motor and sensory |
|
|
Cranial Nerves 1-3 |
1. Olfactory: smell 2. Optic: sight 3. Oculomotor: eye up, down, medial, react to light |
|
|
Cranial Nerves 4-6 |
4. Trochlear: eye down and lateral 5. Trigeminal: touch, pain, mastication/mouth muscles, sinuses, face 6. Abducens: lateral gaze |
|
|
Cranial Nerves 7-9 |
7. Facial: taste, touch, pain facial muscles/expressions 8. Vestibulocochlear: hearing, balance/equilibrium 9. Glossopharyngeal: touch, pain, taste, pharynx muscles, gag reflex |
|
|
Cranial Nerves 10-12 |
10. Vagus: touch, pain; muscles of palate, pharynx, laynx; gag relfex, speech 11. Accessory: sternocleidomastoid and trapezius 12. Hypoglossal: tongue |
|
|
Spinal Nerves |
31 pairs originate from spinal cord; eventually become PNS; Motor and sensory function; From EACH side of spinal column: -8 cervical -12 thoracic -5 lumbar -5 sacral -1 coccygeal |
|
|
Cervical Nerves 1-4 |
From cervical plexus; sensation from upper part of shoulders to back of head and front of neck |
|
|
Cervical Nerves 5-8, Thoracic Nerve 1 |
From brachial plexus; motor and sensory function to upper extremity and most of scapula |
|
|
Thoracic Nerves 2-12 |
Run directly to areas in thorax (between neck and abs) |
|
|
Lumbar, Sacral, Coccygeal Nerves |
Supply sensation and motor function to lower trunk, lower extremity, and perineum |
|
|
Dermatome |
defined area of skin supplied by a specific spinal nerve |
|
|
Myotome |
muscle or group of muscles supplied by a specific spinal nerve |
|
|
Neurons |
Basic functional unit of nervous system responsible for generating and transmitting impulses and consist of: -cell body -dendrites (transmit to cell body) -axon (transmits away from cell body) |
|
|
Neurons classified into 3 types... |
Motor (away from CNS to muscle and glandular tissue), Sensory (to CNS), Interneurons (conduct impulses from sensory to motor) |
|
|
Proprioceptors |
internal receptors that provide feedback about tension, length, contraction state of muscle, position, and movement of joints
|
|
|
Kinethesis |
conscious awareness of position and movement of body in space |
|
|
Proprioceptors specific to muscles |
Muscle spindles, GTOs |
|
|
Proprioceptors specific to joints and skin |
Meissner's, Ruffini's, Pacinian corpuscles and Krause's end-bulbs |
|
|
Proprioception |
Subconscious effort to regulate posture and movement |
|
|
Muscle Spindles and myotatic stretch reflex |
Sensitive to stretch and rate of stretch; 1. Rapid muscle stretch happens 2. Impulse sent to CNS 3. CNS activates motor neurons of muscle to make it contract Protects muscle; Ex: Reflex hammer on knee (patella tendon reflex) |
|
|
Golgi Tendon Organ |
Tension in tendons and GTO increases as muscle contracts and... 1. GTO threshold reached 2. Impulse sent to CNS 3. CNS causes muscle to relax 4. Facilitates activation of antagonists as a protective mechanism |
|
|
Pacinian corpuscles |
Around joint capsules, ligaments, tendon sheaths, beneath skin; Activated by rapid changes in joint angle and pressure; activation brief so not good at detecting constant changes; Helpful telling location of body part in space in quick movements (jumping) |
|
|
Ruffini's corpuscles |
Deep layers of skin and joint capsule; Activated by strong and sudden joint movements and pressure changes; Activation continues as long as pressure maintained; Detects even the smallest joint changes |
|
|
Meissner's corpuscles and Krause's end-bulbs |
Skin and subcutaneous tissue; receives stimuli from touch |
|
|
All or None Principle |
regardless of number, individual muscle fibers within a given motor unit will either fire or contract maximally, or not at all |
|
|
Number of muscle fibers may be increased by... (3) |
activating those motor units that have a greater number of fibers, activating more motor units, increasing the frequency of motor unit activation |
|
|
Subthreshold stimulus |
stimulus not strong enough to create action potential = no contraction |
|
|
Threshold stimulus |
stimulus becomes strong enough to produce action potential in a single motor unit axon = all muscle fibers in motor unit contract |
|
|
Submaximal stimuli |
stimuli strong enough to make action potentials in additional motor units |
|
|
Maximal stimuli |
stimuli strong enough to produce action potentials in all motor units of a particular muscle |
|
|
Phases of single muscle fiber contraction/twitch (4) |
1. Stimulus 2. Latent Period 3. Contraction 4. Relaxation |
|
|
Summation |
When successive stimuli are provided before relaxation phase of firsttwitch has completed, subsequent twitches combine with the first to produce asustained contraction = greater tension generated than single contraction; inc in frequency = inc in total muscle tension |
|
|
Tetanus |
happens if stimuli so frequent no relaxation occurs between contractions |
|
|
Treppe |
happens when multiple max stimuli at low frequency to allow complete relaxation between contractions; tension increases over the first few stimuli |
|
|
Greatest amount of tension can be produced when? |
muscle stretched between 100-130% of its resting length; tension zero when shortened to 50-60% of length |
|
|
Rotary Component |
component of muscular force that acts perpendicular to long axis of bone (lever); 90deg = all the muscular force is rotary force (100% of force contributing to movement) |
|
|
Angle of Pull: Less than 90 degrees |
Force is a stabilizing force bc pull directs bone toward joint axis |
|
|
Angle of Pull: More than 90 degrees |
Force is a dislocating force bc pull directing bone away from the joint axis |
|
|
Uniarticular muscles |
Cross and act directly on the joint they cross (ex: brachialis) |
|
|
Biarticular muscles |
Cross and act on two different joints (ex: knee) |
|
|
Multiarticular muscles |
Act on three or more joints due to the line of pull between their origin and insertion crossing multiple joints |
|
|
Active and Passive Insufficiency |
Active: reached when muscle shortened to where it can't generate/maintain active tension Passive: reached when opposing muscle stretched to point where it can't lengthen and allow movement |
