Biomechanics Midterm Flashcards

0
Q

What is the arrangement of fusiform muscles (spindle shaped)?
How does their range of motion compare?

A

fibers arranged parallel and with large cross section diameter
produce a greater range of movement than similar sized muscles with pennate arrangement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What are parallel muscles?

A

fibers arranged parallel to the length of the muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pennate muscles

A

Have shorter fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Unipennate muscle

A

attached to main tendon; fibers come in at an angle

ex. ext. digitorum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

bipennnate musclle

A

ex. rectus femoris

pulls on centraltendon ith fibers on both sides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

multipennate

A

multiple groups of fibers converge on one tendon in various directions
ex. deltoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Convergent muscles (fan shaped)

A

broad origin, pointed insertion
the direction of the pull can be varied –> versatile
ex. pectoralis major –> different parts can be active at different times

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Circular muscles

A

sphincters, eyes, mouth

closes down round areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Muscle Actions

A

Strength, power and torque

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Muscle action: strength

A

the max force a muscle can produce for a single max effort

the amt of tension a muscle produces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

muscle action: power

A

work done over a given period of time (work/time)

a muscle contracting in a very brief amount of time (high power)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

muscle action: torque

A

muscle force causing rotary movement of a body around an axis; a turning or twisting force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Muscle action: Contraction

What can they be used for?

A

tension developed in a muscle as a result of a stimulus
Used for: cause, control and prevention of joint movement
- initiate or accelerate movement of a body segment (usually contraction)
- slow down or decelerate movement of segment (usually stretching/lengthening –> controlling)
- prevent movement of a body segment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main types of muscle contraction?

A

Isometric (same measure): muscles do not shortern/lengthen, but still produce tension

Isotonic: (same tone) lengthen or shorten, but maintain a consistent tone

  • Concentric: to the center; bring together
  • Eccentric: away from the center; bring apart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Isometric contraction

A

tension developed within a muscle without joint motion –> static contractions
Occurs when the tension a muscle develops is the same as the force applied to that muscle
USED TO STABILIZE JOINTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Isotonic contractions

A

muscle contraction without appreciable change in the force contraction –> maintains tension under a constant load
- tension is developed within a muscle
FINISH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Concentric contraction

A

muscle develops tension as it shortens
occurs when a muscle develops enough tension to overcome the resistance appllied to it
used to initiate movement against gravity or resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Eccentric contraction (away)

A

muscle lengthens unders tension (gradual lowering under high weight)
muscle tensions is less than the resistance applied to it
- results in controlled joint motion
USED TO DECELERATE BODY SEGMENT MOVEMENT
**produce the most tension out of all types of contraction; most demanding type of contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Line of pull

A

direction of movement produced by the contracting muscle
- the pull of a muscle from its rigin to insertion
change can occur with change in joint position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Line of pull is a function of what/

A

the muscles attachment
the plane of joint motion
the muscles distance from the joint’s axis of rotation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens when the line of pull is altered from its optimal position due to muscle weakness or poor posture?

A

the muscle will be inefficient, work harder and have more strain put upon it.
This can lead to muscle and/or joint injury.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Angle of pull**

A

the angle betewen the line of pull of the muscle and the bone on hich it inserts

  • a muscles angle of pull changes with every degree of joint motion
  • a vertical component of the angle is always perpendicdular to the lever (attachment) and causes rotational movement at the joint axis (90* –> 100% rotational)
  • a horizontak component of the angle of pull is always parallel to the lever and causes non-rotational movement at the joint axis (angle or 45*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is muscle action is dependent upon?

A
# of motor units activated
type of motor unit activated
size of the muscle
initial muscle length
angle of the muscle and joint
speed of muscle contraction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Reverse action of concentric muscle contractions

A

when a muscle contracts it pulls both ends toward the center of the muscle

  • if neither of the bones attachments are stabilized, then bones are puled toward another
  • usually, one bone is more stabilized and the less stabilized bone usually moves toward the more stabilized (ex. biceps curl - open chain; chin up - closed chain)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Range of motion

A

depends on length of muscle fibers (long = large range; parallell and fusiform muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does power depend on?

A

total number of muscle fibers
many fibers = great power
(convergent, unipennate, bipennate, multipennate muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

4 Properties of muscle force production and movement

A

irritability or excitability
contractility
extensibility
elasticity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Irritability (excitability)

A

property of muscle being sensitive or responsive to chemical, electrical or mechanical stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Contractility

A

ability of muscle to contract and develop tensions (innternal force) against resistance when stimulated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Extensibility

A

ability of muscle to be passivle streatched beyond its normal resting length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Elasticity

A

ability of muscle to return to its original length following stretching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Interdigitation

A

a muscle may be innervated by more than one nerve and a particular nerve may innervate more than one muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What roles doe muscles work in?

A

Prime mover (Agonist)
Antagonist
Synergist
Stabilizer (fixator)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Prime movers (Agonists)

A

muscles that assume the major responsbilioty for producing a specific movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Antagonists

A

muscles that oppose or revers the movement by prime mover

  • if the prime mover is active, antagonist is released
  • antagonist also help regulate the action of the prime mover by partially contracting to provide some resistance or to slow or stop
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Synergist

A

a musclle which performs or assists the same same join motion as the agonist

  • two muscles are callded synergeists that act to control morion of the prime mover
  • immovbilizw the origin of the prime mover so that the prime mover can act more efficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

STabilizers (fixator)

A

synergists that act to control motion of the prime mover

  • immobilize the origin of the prime mover so that the prime mover can act more efficiently
  • tends to be continuous low-level muscle activity with either isometric or eccentric pull
    (ex. deltoid is the prime mover of arm abduction)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Mechanical Levers

A

Purely physical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

LEver

A

a riigid bar that moves on a fixed point (bones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Fulcrum

A

a fixed point of leverage (joint)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Effort

A

force appllied to move a resistance (tension/torque)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Load

A

resistance to be moved (bone, tissue mass and objects to be moved)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Mechanical advantage lever 9power lever)

A

load is close to fulcrum
effor applied far from the fulcrum
small effort appllied over a relatively long distance can be used to move a large load over a small distange
* such a leverl operates as a mechanial advantage and is commonly caled a power lever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Mechanical Dsiadvantage (speed leverage0

A

load is far from fulcrum
efost is applied new the fulcrum
The force exerted must be great ha the moved moved
- useful because they allow the load to move rapidly through a larger range of motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Mechanical Muscke

A

A lever allows

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

1st class levers

A

dvvd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Second class levers

A
the load (resistance) lies between fulcrum and effort
* we dont have many of these
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q
Third class levers
*Most of what we have in the body
A

effort is applied at t apoint between the load and the fulcrum
great speed with mechanical disadvantage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Functional Organization of Skeletal Muscles

A

Muscles –> fascicles –> muscle fibers (cells) –> myofibrils –> Thick and thin filaments
Each layer is wrapped with fascia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Sarcomere

A

Contains Thick and Thin Filaments

Make up a Myofibril

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Myofibrils

A

Surrounded by: Sarcoplasmic Reticulum

Consists of: Sarcomeres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Muscle Fiber

A

Surrounded by: Endomysium
Contains Myofibrils
Types: Fast, ballistic (glycolytic fuel source); postural;
* Can contain multiple types of fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Muscle Fascicle

A

Surrounded by: Perimysium

Contains: Muscle Fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Skeletal Muscle

A

Surrounded by: Epimysium

Contains: Muscle Fascicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Neuromuscular Juntion

What are the 5 basic components?

A

The site where the axon and muscle fiber communicate

  1. Motor Neuron
  2. Motor end plate
  3. Synaptic Cleft
  4. Synaptic Vesicles
  5. Neurotransmitters
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is the motor stimulation mechanism for muscle contraction?

A

Motor impulses cause the release of acetylcholine (ACh) from synaptic vesicles which bind to receptors on the motor end plate and generate muscle contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is the process of muscle relaxation?

A

acteylcholinesterase breaks down acetylecholine
motor neuron impulses stop
calcium moves back into sarcoplasmic reticulum
myosin and actin binding prevented

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is a motor unit?

A

a single motor neuron and all the muscle fibers it controls

  • the functional connection between the nervous system and the muscular system
  • when a motor unit fires, all the muscle fibers contract together
  • one neuron may innervate several muscle fibers
  • one muscle fiber may be innervated by several motor neurons
    • this creates both large and small motor units
  • One muscle fiber may act with several motor units depending upon demand (interdigitation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is an example of fine control? Strength control?

A
extraocular muscles (20 fibers)
gastrocnemius (1,000 fibers)
59
Q

Twitch

A

a single brief stimulus to a muscle that produces a quick cycle of contraction and relaxation lasting less than 1/10 second

  • a single twitch is not strong enough to do any useful work
  • normal activities require more tension than is produced this way
  • CHART ON TETANUS - measure twitches by pulses per second –> summation of twitches –> tetani
60
Q

Treppe

A

Gradually increased contraction intensity… a rapid sequence of stimuli cause the muscle twitches to fuse together, each contraction being stronger than the one before… gradually generate more strength contraction
- occurs with

61
Q

Tetanus (incomplete)

A

very rapid sequence of stimuli

- occurs with higher frequency stim

62
Q

Tetanus (complete)

A

very rapid sequence of stimuli

50 + pps

63
Q

What are the 3 functional classifications of neurons?

A

Sensory
Motor
Interneuron

64
Q

Sensory Neurons

A

afferent neurons

- transmit impulses from receptors to the brain or spinal cord

65
Q

Motor neurons

A

efferent neurons

- transmit impulses from the brain or SC to the effetor sites such as muscles, glands or organs

66
Q

Interneuron

A

association neurons

- transmit impulses from one neuron to another –> bridge

67
Q

Nociceptive neurons

A

“Pain” fibers
“warning fibers”
(MOTOR Neurons)

68
Q

Nerve Fiber classification

A

A, B, and C *doesn’t test much on this

69
Q

A fibers: myelinated

subtypes

A

A alpha: fastest conducting and largest diameter; motor efferents; muscle spindle afferents
A - beta(50 ms): touch and pressure afferents (mechanoreceptors)
A-gamma (20 ms): motor efferent to muscle spindle
A-delta (15 ms): skin temperature and pain (noxious stimuli)

70
Q

B fibers

A

7 ms

myelinated, slow

71
Q

C fibers

A

unmyelinated
we don’t deal much with these
temperature, pain, itch

72
Q

What is the Spinal Cord Reflex Arc

A

a functional unit of the nervous system; automatic response to stimulus without conscious thought

73
Q

What are the 5 basic components of the spinal cord reflex arc

A
  1. sensory receptor: transmits APs stimulated by sensation
  2. Sensory Neuron: transmits impulses to SC
  3. Interneuron: connects or switches impulses to other neurons
  4. Motor Neuron: transmits motor impulses
  5. Effector Organ: responds with reflex contraction of muscle or gland
74
Q

Proprioception

A

The sense of position and movement of one’s sown limbs and body without using vision (somatosensory)

  • sense of body and limb position
  • sense of speed and direction of limb joint movement
  • sense of muscle length and tension
  • Travels on posterior tracts - dorsal columns (myelinated) to increase speed of information
75
Q

What 3 types of mechanoreceptors detect proprioception

A
  1. Muscle spindle Receptors
  2. Golgi tendon organs: located in tendons of muscle, neuromusc jxn
  3. Joint kinesthetic receptors:
76
Q

Muscle Spindle Receptors

A

located within the fleshy part of the muscle and consists of special intrafusal muscle

  • ends of the intrafusal fibers are contractile and attach to the extrafusal fibers
  • the spindle detects the rate at which the muscle fibers are stretched and their length
  • changes in length of muscle fibers aids in coordination and efficiency of muscle contraction
77
Q

Muscle Spindle Receptors: Intrafusal Muscle fibers

What are the 2 types?

A

modified muscles fibers enclosed in a capsule within extrafusal fibers (normal, voluntary skeletal muscle)

  1. Nuclear Bag Fibers
  2. nuclear chain fibers
78
Q

Nuclear Bag Fibers

A

nuclei are concentrated in the central “bag” part of the fiber

  • the ends of the fibers are striated and contractile
  • the contractile fibers are attached to the extrafusal fibers
  • the contractile ends receive input from gamma motor neurons
  • the nuclear bag is sensitive to sudden rate of change in muscle length (phasic)
79
Q

Nuclear Chain fibers

A

nuclei are spread in a “chain like” fashion in the center of the fiber
sensitive to slow stretch

80
Q

muscle spindle cont’d

A

central non-contractile region s a wrapped buy type Ia and type II sensory neurons that send input about the rates and amount of length change to CNS
REVIEW SLIDES FOR MORE INFO

81
Q

Agonists

A

causes specific movement or possibly several movements to occur through the process of its own contraction

82
Q

Antagonists

A

lkdfj

83
Q

Golgi Tendon Organs (GTOs)

A

encapsulated nerve endings located at the junction of tendon and muscle; their ends have numerous terminal branches associated with bundles of collagen fibers in the tendon; produces a sudden relaxation of the muscles; Plays a role in muscle tone imbalance, muscle spasm and tendon points
Sensory Innervation only
Dynamic response: sudden increase in muscle tension
AND Static Response: sustained or gradual pull (postural tone)
INVOLUNTARY MUSCULAR RELAXATION

84
Q

What do GTOs detect?

A

Detects:

  • force of muscle contraction
  • tension applied to the tendon
  • prevents contracting muscle from applying excessive tension to tendons
85
Q

Joint Kinesthetic Receptors

A
located in and around synovial capsules, in ligaments
- encapsulated and free nerve endings
Detect: 
- direction of movement of the join
- acceleration
REVIEW
Types: Pacinian, Ruffini, Free nerve
86
Q

Pacinian Corpuscles

A

located in CT and synovial joint capsules

respond to rapid pressure changes, stretch, acceleration and deceleration of joint movement

87
Q

Ruffini Corpuscles

A

located in synovial capsules and ligaments
respond to deep rapid and sustained pressure; especially responsive to lateral stretch
detects changes in joint angles
ligament receptors adjusts muscle tone

88
Q

Free nerve endings

A

located in most body tissues - joint capsules, ligaments, tendons, fat pads, menisci and periosteum
respond to rapid and sustained pressure

89
Q

Proprioceptors Affect on Muscle Tone

3 reflexes

A
  • automatic response without conscious through
    1. Quick Stretch Reflex
    2. Reciprocal Inhibition
    3. Autogenic Inhibition
90
Q

How is the reflex arc tested?

A

Tested by DTRs: deep tendon reflexes –> test the simple reflex arc
hyporeflex: inhibit reflex; diminished reflexes
hyper-reflex: upper motor neuron (SC, brainstem, cerebellum and up) lesion?

91
Q

Quick stretch reflex

A

telex response from muscle spindles

  • produces contraction of the muscle being stretched
  • fxns: monitors status of muscle activity; guards against potential injury; respond to rapid and sustained pressure

MORE INFO IN SLIDEs

92
Q

Reciprocal Inhibition

A

sdlkf

93
Q

Autogenic Inhibition

A

a muscle inhibits itself - an inhibitory response to a muscle that develops too muscle tension, either via shortening or lengthening
comes through the GTOs

94
Q

FXNS of Autogenic Inhibition

A
  • guards against potential injury to a muscle’s fibers

- muscle relaxation reduces tension applied to the muscle and endows and protects them from damage

95
Q

Sequence of Autogenic Inhibition

A

stretching the tendon (via contraction or passive stretch) increases the tension in the tendon and activates the afferent GTOs
- the GTO neurons synapse in the SC with inhibitory interneurons
REVIEW remainder
–> GTO stretched –> Ib afferent –> inhibitory interneuron relaxes agonist –> excitatory interneuron contracts antagonist

96
Q

Roll

A

multiple points along one rotating articular surface contact multiple points on another articular surface
(a tire rolling across the pavement)
femoral condyle on the tibial plateau
occurs on incongruent (unequal) surfaces
usually occurs in combination with sliding or pinning

97
Q

Slide

A

(glide) a single point on one articular surface contacts multiple points on another articular surface

98
Q

Spin

A

(like a top on the floor) a single point on one articular surface rotates on a single point on another particular surface; rotates around a stationary longitudinal mechanical axis

ex. head of the radius at the humeroradial joint during pronation and supination
* does not occur by itself during normal joint motion; occurs as a combination motion

99
Q

Distraction and longitudinal traction

A

joint surfaces are pulled apart

use to stretch a joint capsule and mobilize a joint

100
Q

Compression

A

decrease in the space between two joint surfaces
adds stability to a joint
normal response to muscle contraction

101
Q

Can arthrokinematic movement between joint surfaces be reproduced by muscles?

A

No, they must be produced in the joint on their own. It is what we are restoring during manipulations.

102
Q

Convex-on-concave and vice versa rule:

A

describes the relationship of rolling and sliding motion within a joint when one joint surface is convex and the other surface is concave

103
Q

Convex on concave motion

A

the concave side = stabilized (anchored)

the convex joint surface slides in the opposite direction as it rolls

104
Q

Concave on convex motion

A

the convex side = stabilized

the concave joint surface

105
Q

Clinical significance of Convex-concave rule

A
  • rules serve as a basis for joint mobilization techniques
  • physiological movements
  • accessory movements
  • joint play
  • end-feel
  • Tx often combines facilitation of physic mobilization and accessory movements to restore particular joint movement
  • ONE MORE
106
Q

Physiological Movements

A

movement of bones done voluntarily (osteokinematics)

107
Q

Accessory Movements

A

the name given to the arthrokinematic movements within the joint and surrounding tissues that are necessary for normal joint range of motion, but cannot be performed voluntarily

  • necessary for full range of physiological motion to occur
  • ligament and joint capsule limitations cause movement restrictions or aberrant joint motion
108
Q

Joint Play

A

motions that occur within the joint but only as a response to an outside force

  • determined by joint capsule’s laxity
  • can be demonstrated passively, bout not performed actively
109
Q

End-feel

A

a way to interpret and measure joint play movements

what stops it? joint capsule, scar tissue, etc.

110
Q

Joint Mobilization Techniques

A

ADD INFO

111
Q

Plane

A

a flat surface determined by the position of three points in space

  • sagittal
  • frontal (coronal)
  • transverse (axial)
112
Q

Plane motion

A

motion in which all points of a rigid body move parallel to a fixed plane (two dimensional movement)

113
Q

What plane motion occurs in the sagittal plane?

A
  • flexion

- extension

114
Q

That plane motion occurs in the frontal (coronal) plane?

A

right and left lateral flexion

115
Q

motion occuring in the transverse (axial) plane?

A

ADD

116
Q

Axis of motion

A

a line around which rotary movement takes place or along which translation occurs

117
Q

X, Y and Z axes

A

sdf

118
Q

Degrees of freedom

A

the number of ways in which a body can move

  • one degree of freedom would be translation or rotation about one axis
  • spinal segments exhibit 6 degrees of freedom
119
Q

Instantaneous Axis of Rotation (IAR)

A

when a rigid body moves in a plane, at every instant there is a point in the body or some hypothetical extension of it that does not move; AXIS IS MOVEABLE/DYNAMIC

  • an axis perpendicular to the plane of motion and passing through that point is the instantaneous axis (center) of rotation for that motion at that instant
  • used to describe any vertebra motion in 2D space
  • as different force vectors are applied, they may cause a shift in the IAR
120
Q

Motion Segment

A

the functional unit of the spine

  • smallest spinal segment exhibiting biomechanical characteristics similar to those of the entire spine
  • 6 degrees of freedom (6 joints on each vertebra)
  • 2 adjacent vertebrae and everything that connects them.
121
Q

Pain generators of the spine

A

outer third of the disc, the ligaments that attach to vertebrae, intersegmental muscles, capsules around the facet joints

122
Q

Coupled Motion

A

the consistent association of one motion (translation or rotation) about one axis with another motion about a second axis

  • one motion cannot be produced without the other
  • two motions occurring at the same time along two different axes.
123
Q

loose-packed joint position

A
  • joint capsule and ligaments are most relaxed
  • max joint play is possible
  • articulating surfaces are maximally separated
  • position used for traction or joint mobilization
  • facet joint loose-packed position = half way between flexion and tension
124
Q

closed-packed joint position

A
  • the capsule and ligaments maximally tightened
  • there is no joint play
  • there is maximal contact between the articular surfaces
  • either in flexion or extension
125
Q

spine review

A
33 vertebrae (7 C, 12 T, 5 L, 5 S, 1 - 4 Coccyx)
Cervical = a lot of rotation; 
Thoracic Nn = autonomic (sympathetic) 
Cervical and Sacral (Craniosacral) Nn = parasympathetic
** don't only be thinking about muscles and joints --> Nervous System too!
126
Q

Regional Coupling

A

more than one motion is occurring at the same time

127
Q

Occiput (CO)

A

Condyles:

  • face laterally and inferiorly
  • form convex rockers
  • sit in concave surface of superior articular facet of C1
128
Q

Atlas (C1)

A

Facets:

  • concave surface
  • ADD INFO
129
Q

C0-C1 Flexion and Extension

Lateral Flexion

A

FLEX/EXTEN:
- occiput glivers post. with flexion and ant. with extension
greatest range of motion in C0-C1
- ROM: excursion is 10* flexion to 25* extension
LATERAL FLEX:
- occiput rolls on side of lateral flexion and glides on opposite side; ROM = 5* each side (minimal)
**IMPT to know about stability bc too much movement could put pressure on SC

130
Q

Lower Cervical Biomechanics (c3-c7)

A

Design is consistent from C3 - C7
Vertebral body is wider transversely than A-P
Transverse foramen for vertebral artery
*bifid spinous processes

131
Q

Articular facets for lower cervicals - describe angles in planes and the articular surface.

A

articular facets are at a 45* angle with transverse (horizontal) plane
parallel in frontal (coronal) plane
articular surface is nearly flat
* coupled motion

132
Q

Joints of Lushka

A

aka uncinate processes; give the cervical spine more stability
form age 6 - 9 and completed by age 18
limit lateral flexion to only a few degrees
serve as guides to couple lateral flexion with rotation (coupled motion)
synovial joints; can become inflamed

133
Q

Curves of the cervical spine

A
Lordotic curve of 20 - 50* (average is 45*)
begins C1 and extends to C7
facet and disc planes determine curve
secondary curve
develops in response to upright posture.
134
Q

cervical something

A

disc-height-to-body ratio: 2.5, allows for greater TOM in cervivals
25% height of cervical curve
highly anteriorly, conntibutes to cervical lordosis
nucleus pulposus slightly posterior ot center

135
Q

Lower cervical Flexion and Extension

A

Flexion and extension predominate over the other motions
average range of motion is 15* per segment for combined flex-extension
*important, moving forward and backward of one vertebrae on the other

136
Q

Flexion - lower cervical

A

anterior disc compression –> posterior distraction

Facets glide apart producing stretching and joint gapping

137
Q

Extension - lower cervicals

A

anterior disc distraction - posterior compression

facets approximate –> compression at inferior margins

138
Q

Lateral Flexion of C vertebrae

A

average lat flexion range is 7 - 8* to each side
lateral flexion decreases as move caudally down cervical spine
coupled motion MORE INFO
lateral disc wedging and approximation are present on the side of lateral flexion and distraction is present on the side opposite lat flexion
- the inferior facet glides down and medially on the side of lateral flexion and up and laterally on the side opposite lateral flexion

139
Q

Lower cervical rotation

A

average ROM = 5* to each side
rotation decreases significantly
lateral flexion gets a lot of rotation , but rotation only gets a little of lat rotation

140
Q

Typical Thoracic Biomechanics

A

transverse processes are thick, strong and long
SPs are long and slender
Costovertebral joints on side of vertebral bosy articular with rib heads
costotransverse joints on TVPs articulate with tubercles of ribs

141
Q

Thoracic Curve

A

Forward curve - primary curve at birth
kyphotic curve of 20 - 50* (average = 45*)
begins t1-t2 and extennds to T12
apex is at T6 - T7 disc space
flattening will cause: cervical curve to decrease, cervical curve to shift forward, lumbar curve to increase
lumbar curve to

142
Q

Thoracic disc

A

not as vulnerable as cervical or lumbar area
disc height to body ration = 1:5; smallest ratio in spine
contributes to decreased flexibility in thoracic spine
nucleus pulposus located centrally within annulus

143
Q

Flexion and extension - thoracics

A

combined flex-exten = 6; 4 in upper thoracics, 6* in middle, 12* in lower
combines sagittal plane rotation (tilting) with slight sagittal plane translation
Flexion - articular facets glide apart as the disc opens posteriorly
Extension - facet joints and posterior disc approximate

144
Q

coupled motion

A

approx 6* to each side
upper thoracic lat flex is couple with axial rotation
- upper thoracic lat flex and trptation occur to the sam side, body r
- middle and lower can go either way

145
Q

upper thoracic rotation

A

kj