Exam #1 Flashcards
Understanding C7 SCI
key muscles still functioning: C4 - UT, neck mm., Diaphragm C5 - Biceps & wrist extensors C6 - wrist extensors, SA, Lats C7 - Triceps, Intercostals, Abs, back extensors
C7 SCI Best Stretching choice
Active Stretching b/c they have functioning muscles around elbow joint (Biceps/Triceps)
What type of Active Stretching is the best choice for C7 SCI?
Cathy’s opinion: Reciprocal inhibition
When is Passive Stretching most appropriate?
1) No functioning muscles around the joint
2) Contracture has a soft tissue endfeel
3) Prolonged stretching time or equipment is available
Reciprocal Inhibition
Strengthen Triceps while inhibiting (stretching) Biceps
Cross fiber massage
@ musculotendinous junction
Causes firing of GTO (1b afferent)
Inhibits the agonist
Facilitates the antagonist
Hold-relax technique
Strong contraction of Biceps may trigger the GTO to inhibit the Biceps.
Or may induce immediate relaxation of the Biceps after strong contraction.
Contract-relax technique
Active concentric (moving) contraction of Biceps may induce relaxation of Biceps
Muscle Spindles
Sense change in muscle length
complex Intrafusal muscle fibers
1) Nuclear Bag: larger diameter, clustered
~static OR dynamic
2) Nuclear Chain: smaller diameter, more spread out
2 sensory receptors in muscles
Muscle Spindles & Golgi Tendon Organs
function = proprioception
GTO’s
Sense change in muscle tension/force
Extrafusal muscle fibers
"regular muscle fibers" Include Slow (type 1), Fast (type 2a & 2b), and Intermediates (FOG)
1a Phasic afferent neurons
Senses change in velocity and muscle length
Come from Muscle Spindle, DYNAMIC Nuclear Bag Intrafusal fibers
- synapses with either (+) AMN of Agonist or (-) interneuron going to (-) AMN of Antagonist
- also forms DCML ascending tract to the brain
1a Tonic afferent neurons
Senses change in muscle length only
Come from Muscle Spindle, Nuclear Chain Intrafusal fibers
- synapses with either (+) AMN of Agonist or (-) interneuron going to (-) AMN of Antagonist
- also forms DCML ascending tract to the brain
1b afferent neurons
Come from GTO’s near musclulotendinous junction
In series w/ extrafusal muscle fibers
- synapses with either (+) AMN of Antagonist or (-) interneuron going to (-) AMN of Agonist
- also forms DCML ascending tract to the brain
Quick Stretch of a muscle
Causes 1a Phasic & Tonic neurons to fire which facilitate the agonist and inhibits the antagonist
All through the peripheral nerve of that muscle
Want to elicit a Monosynaptic Reflex Arc for facilitation of Agonist OR Disynaptic Reflex Arc for inhibition of Antagonist
Tendon Tapping
Tap tendon, quick stretch of muscle, sensed by 1a Phasic, efferent info comes in, synpases @ AMN, sends info back to Agonist muscle to contract
At the same time, inhibition of Antagonist muscle occurs.
Monosynaptic Reflex Arc
DTR activates 1a Phasics
Responsible for tone
Hypertonic
No inhibitory
UMN lesion always!
Hypotonic
No response to tendon tap
UMN or LMN Lesion
Clonus
Sustained Monosynaptic Reflex Arc
Modified Ashworth Scale
PROM to feel hypertonicity
0 = Normal 1 = Catch & Release 1+ = Catch & Resist 2 = Increased tone throughout ROM 3 = PROM difficult due to increased tone 4 = Very rigid
Deep Tendon Reflex Scale
0/1 = Hypo 2 = Normal 3/4 = Hyper
Tonic Vibratory Reflex
Vibrate skeletal muscle @ high frequency to get tonic contraction via monosynaptic reflex arc
Selectively stimulates Muscle Spindles (1a phasics)
TVR frequency on children
60 Hz with battery vibrator
TVR frequency on adults
100-120 Hz with electric vibrator
TVR effects
Progressively build in strength
Gradually fades out after vibrator is removed
TVR locations
Best on muscle belly or tendon
DO NOT vibrate over musculotendinous junction or GTO’s!
Follow with resistance or active contraction to enhance muscle response and increase motor learning
If Biceps is hypertonic due to flexion synergy, what muscle would you vibrate?
Antagonist = Triceps
b/c facilitates antagonist and inhibits the agonist (Biceps)
TVR precautions
Over 200 Hz = damaged skin
Holding in one place = blisters or bruises
Be careful around pt. with hydrocephalus (area of shunt)
Be careful around major blood vessels around neck (reducing BP or dislodging a clot)
If Biceps is hypertonic due to flexion synergy, what muscle would you perform cross fiber massage on?
Agonist = Biceps
b/c facilitates antagonist and inhibits the agonist (Biceps)
Prolonged Muscle Stretch
Excites 1b afferents
If GTO input to agonist “wins” over Muscle Spindle input to agonist, then GTO will INHIBIT the agonist.
Sensation
Receptors receive and route info to the spinal cord and brain for processing
Perception
Integration of sensation
“Make sense” of sensory info
Proprioception
Besides Muscle Spindles and GTO, there are other inputs from joint and skin receptors
Joint Receptors
Cutaneous receptor
Sense joint position @ ends of ROM (short or long)
ex) III afferents from ligaments & IV from capsules
Dorsal Column Medial Lemniscus
Ascending sensory info
1st order = 1a phasic/tonic, 1b, III, IV (ascend ipsilaterally to medulla)
2nd order = in Caudal Medulla & cross over to contralateral brainstem
3rd order = from Thalamus to Somatosensory cortex
Efferent Motor Neurons
Gamma MN’s (Intrafusal)
- Static innervate ends of static nuclear bag and chain
- Dynamic innervate ends of dynamic nuclear bag
Alpha MN’s
-Innervate extrafusal muscle fibers
Enhanced Proprioception
Happens when dynamic and static Gamma MN’s are firing
Makes muscle spindles more sensitive
Sensory Unit
Composed of sensory receptor, 1 sensory neuron, and its branches
Sensory Receptors
@ surface of skin
ALL are transducers
SOME are modality specific
SOME are polymodal
Free Nerve Endings
Polymodal = cold, warm, touch, pain
Neurons are myelinated/unmyelinated
Receptors are unmyelinated
Around hair follicles, sense direction of light moving touch
Mechanoreceptors
Touch and Pressure
Meissner’s Corpuscles
Phasic Mechanoreceptor
Encapsulated ovoid bodies in hairless portions of skin
Pacinian Corpuscles
Phasic Mechanoreceptor
Central unmyelinated tip surrounded by concentric lamellae (“onion”)
Press on corpuscle, bend receptor, ppens channels (depolarization), NA in & K out
Phasic Receptors
- Fast adapting
- Quick info and then stops (on & off)
- Doesn’t keep sending us info
ex) Pacinian & Meissner’s
Tonic Receptors
- Slow adapting
- Minutes, hours, days
- Gives info for a long time
ex) Muscle Spindle, GTO, Pain receptors, Baroreceptors
Thermoreceptors
Changes in temp. alters permeability of Na+ influx in the neuron membrane
Cold = Krause receptors Warm = Rufini Corpuscle Pain = hot/cold free nerve endings
Nociceptors
Detect pain
ex) inflammation compressing free nerve endings that causes pain will bring info to spinal cord (spinothalamic tract) associated with pain into the brain
Eye-Head-Hand Coordination
First eyes
Then head
Then hand
Eye-Head-Hand Coordination
Initial vs. Final
- entire reach guided by vision
- Initially, need to know vaguely where object is and distance (peripheral vision
- Final part is vision dependant (foval vision)
Smooth Pursuit
Tracking moving object
Keeping object in focus
Can only be done @ certain speed then will shift to saccade
Saccade
Rapid eye movements
Focus on each location w/o noticing anything in between
Cerebellar Trauma (Stroke)
Dysmetria: poor measurement in 3D space when performing saccades
(looks off to the right/left when you think you are focusing on object)
Hypometric
Hypermetric
Dorsal Pathway (Superior)
“Spatial Vision”
- Exits Occipital Lobe to the Parietal Lobe
- Processes spatial relationship b/w you and object
Ventral Pathway (Inferior)
“Object Vision”
- Exits Occipital Lobe to the Temporal Lobe
- Processes physical qualities of object
Transport
Proximal joints moving the hand where it needs to be
Transport within arms length
Trunk is STABLE
-scapula, shoulder, elbow, forearm moving
Transport beyond arms length
Trunk is DYNAMIC
- sitting includes the trunk
- standing may include the LE’s too
Within arms length facilitation
-Facilitation of abs and lumbar (co-contraction)
Beyond arms length facilitation
- Facilitate weight shift over Ischial Tube. (same side as reach)
- Diagonal is lateral & anterior
- Facilitate pelvic tilt (posterior>anterior)
- Facilitate lumbar (flexion>extension)
- Facilitate trunk elongation on reach side
- Facilitate trunk lateral flexion on contralateral side
Scapula protraction
ABD, up rotation, elevation
Scapula retraction
ADD, down rotation, depression
Ankle Strategy
- Facilitate weight shift to ipsilateral foot and trunk elongation (dynamic)
- keep body/knees straight and just pivot @ ankles (DF)
Hip Strategy
-Facilitate trunk/hip flexion & ankle PF (dynamic)
- Pelvis COM shift posterior
- Chest COM shift anterior
Stepping Strategy
- Facilitate through pelvis to encourage step (diagonal lateral & anterior shift)
- Facilitate through upper chest & lower trunk elongation
UE Reaching
-Faciliate scapula protraction, shoulder elevation and elbow extension
(maybe a little wrist flexion and MCP extension)
Grasp
- Distal joints of the wrist and hand performing manipulation
- Fine motor control
Whole Hand Grasp
- Need to open fingers larger than width of object and then close fingers to grasp object
- Open 2-3 times larger than object
- Smaller object = use thumb and index
Whole Hand Grasp and Lift
-Need to do the same as normal grasp but must match the grasp force to the weight of the object in order to lift it
The Reaching Movement
Vary the task and object characteristics to drive movement outcomes
Spatial Trajectory
Reaching = Multi-joint movemnt = straight line trajectory (more complex calculation)
-Single joint movment would make a curvilinear trajectory
Variability in Spatial Trajectory
Some variability is normal
Patients who have problems planning or executing direction of movement may move slow enough to realize they are off and have enough time to correct themselves.
Pointing Effector
Tip of index finger
Grasp Effector
Tips of thumb and index finger
Punch Effector
Knuckles
Joint Reversal Movement
Joint needs to flex more than extend to reach for an object or get to an endpoint
Accuracy (Distance error vs. Direction error)
Distance error = force calculation is off
Direction error = calculation of multi-joint movements is off
*both increase with distance
Constant Error (CE)
Distance from the mean endpoint location to the center of target
Variable Error (VE)
Measure of error dispersion
1 standard deviation in the X&Y directions
Speed-Accuracy Tradeoff
Increase speed = Decrease accuracy
Decrease speed = Increase accuracy
Fitt’s Law
MT=a+b log2 (2A/W)
MT = movement time A = amplitude (distance start to target) W = width of target
Clearance
Movement around obstacles
Forces curvilinear trajectories
Minimum clearance = closet approach to obstacle
- move fast = increase min. clearance
- move slow = decrease min. clearance
Hand Grasp
-Max aperture @ 60-80% of reach
Pre-shaping AS YOU REACH
Maximum Aperture
- 5-3 times larger than object width
- Fingers start to match shape of object @ END of reach trajectory (not pre-shaping!)
- Then fingers mold to match object AFTER CONTACT
Johansson & Westling Grip Force
Less grip force needed for Sandpaper vs. Suede vs. Silk
Varying Grasp
- size and shape of object
- weight and texture of object
- orientation of object
- use of object
- “slipperyness”
- fragility of object
- vary functional use
- write, throw, lift, manipulate
- stationary vs. moving objects OR person (taxonomy)
- environment stationary or moving
Interlimb Timing Constraints and Phase Characteristics
Both hands are temporally and spatially linked
ex) stroke pts. use uninvolved limb to drive movement patterns and timing in affected limb
Interlimb Timing Constraints and Phase Characteristics
Both hands are temporally and spatially linked
ex) stroke pts. use uninvolved limb to drive movement patterns and timing in affected limb
Momentum Strategy
- Motion by head, lead shoulder and trunk
- Immediately followed by lead UE reaching
- Lead leg may lift and rotate over opposite leg
Force Strategy
- pt. pushes w/ LE in a flexed position to get them sidelying
- flexion of shoulder, head, trunk and lead UE assisting
1st common form of rolling
Arms = lift & reach above shoulder level HT = shoulder girdle leads Legs = unilateral lift
2nd common form of rolling
Arms = lift & reach above shoulder level HT = shoulder girdle leads Legs = Unilateral push down through heel with far side leg
3rd common form of rolling
Arms = lift & reach above shoulder level HT = shoulder girdle leads Legs = bilateral lift
1st common form of supine to standing
UE = symmetrical push Axial = symmetrical LE = symmetrical squat
2nd common form of supine to standing
UE = symmetrical push Axial = symmetrical LE = asymmetrical squat
3rd common form of supine to standing
UE = asymmetrical push and reach Axial = partial rotation LE = half kneel
1st common form of supine to standing (4-7yrs.)
UE = asymmetrical push Axial = forward w/ rotation LE = asymmetrical wide-based squat
Supine to Erect Stance
- symmetrical form of rising = greatest control of direction and force
- 15 year olds
- less balance = partition movement into discrete components
- taller/lighter pts. = more advanced symmetrical
- shorter/heavier pts. = more basic asymmetrical
Sit to Stand Task
move COM from buttock BOS to feet BOS
Sit to Stand Neck Joint
Neck = flexion to extension
0% - 2deg flexed
30% - 4deg flexed
100% - +4deg extended
8deg total neck movement
STS Momentum Strategy
- requires a certain amount of speed
- no breaks in motion
- accelerate then decelerate the COM
- concentric forces to propel body
- eccentric forces to control body motion
STS Force Strategy
- frequent stops
- bring COM over BOS and stops
- Then, LE forces lift of the body into standing
Momentum Strategy: Phase 1
“Flexion-Momentum”
Begins: movement initiation
End: just before butt lift-off
- weight shift COM horizontal
- E. Spinae eccentric control
Momentum Strategy: Phase 2
“Momentum-Transfer”
Begin: butt lifted
End: max ankle DF
- transfer of momentum from upper body to total body
- hip & knee extensors contract
Momentum Strategy: Phase 3
“Extension”
Begin: after max ankle DF
End: hips stop extending
-body moves vertical
Momentum Strategy: Phase 4
“Stabilization”
Begin: after hip extension
End: stabilization completed
Momentum Strategy Safety
Backward fall = rushing phase 1&2, not getting COM over BOS
Forward fall = phase 3 too late, COM too far over BOS, accelerate too much and decelerate too late
Force Strategy: Phase 1
Trunk flexion & APT to bring COM over feet
Force Strategy: Phase 2
Trunk, hip, knee extension w/ force to bring body to vertical
Force Strategy: Phase 3
Stabilization
Sit to Stand Interventions
- Manually assist @ knee (prevent buckling)
- Progress from higher to lower seat height
- Pressure downward through knee and foot to facilitate WB
Sit to Stand Rules
Feet shoulder width apart
Anterior symmetrical alignment
Sagittal view aligned but feet can be staggered
Stand to Sit
- Eccentric control of body as pt. lowers
- Eccentric paraspinals, quads, gastroc/soleus
Typical Stand to Sit
- Forward trunk movement
- Downward trunk movement
- Knee Flexion
- Backward trunk movement
Stand to Sit Common Maladjustments
-Decreased eccentric control (plopping) -Hip flexion initiating movement -COG too far back -Too much UE use -Unequal weight distribution in LE
Sit to Stand Common Maladjustments
- COG kept posterior
- Feet in front of knees
- Hip extension before knee extension
- Using back of legs to assist
- Too much UE use
- Unequal weight distribution in LE
Sit to Stand Common Maladjustments
- COG kept posterior
- Feet in front of knees
- Hip extension before knee extension
- Using back of legs to assist
- Too much UE use
- Unequal weight distribution in LE
Patients who have trouble with Gait Initiation
PD
MS
CVA
TBI
Center of Pressure
- Location of vertical GRF measured by a force plate
- Equal & opposite to a weighted average of the location of all downward forces acting on the force plate
- Independent of COM!
Gait Initiation w/ RLE
- Ankle Strategy
- 1st 40% = Left DF contract to accept weight shift, Quads decelerate Left knee flexion, then Right GS & HS bring leg forward
Steady-state gait velocity
Achieved in 1-3 steps for healthy individuals
Gait Initiation: PD
- stooped posture
- shuffling gait
- smaller steps
- lack of heel strike
- can’t extend knee or PF in terminal stance
- forward trunk flexion
- no arm swing
- freezing or festinating gait
Gait Obstacle Clearance
- Older people do not step over obstacles with higher clearance b/c legs are heavy, takes more energy, need more strength, challenges balance.
- Instead, they slow down their approach and clearance speed and take shorter steps
Stair Ascent/Descent
- No concentric = trouble with stair ascent
- No eccentric = trouble with stair descent
4 out of 5 falls occurs during…
stair DESCENT
Stair Ascent Phases
Stance (64%)
- weight acceptance phase
- pull up
- forward continuance
Swing (36%)
- foot clearance
- foot placement
Greatest point of instability during stair ascent is…
@ contralateral toe off
-when the ipsilateral leg accepts body weight and ipsilateral hip, knee, ankle are in flexion
Stair Descent Phases
Stance
- weight acceptance
- forward continuance
- controlled lowering
Swing
- leg pull through
- preparation for foot placement
Sit to Stand Trunk Joint
Trunk = flexion to extension
0% - 10deg rapid flexion
45% - 42deg flexed, begin rapid extension
100% - extend to vertical
Sit to Stand Pelvis Joint
Pelvis = PPT to APT to PPT
0% - 26deg behind vertical (PPT)
50% - 12deg in front of vertical (APT)
100% - 1deg in front of vertical (PPT)
Sit to Stand Hip Joint
Hip = flexion to extension
1st 40% - flexion
2nd 60% - extension
Sit to Stand Knee Joint
Knee = extension throughout
1st 40% - 6deg extension
2nd 60% - 76deg extension
Sit to Stand Ankle Joint
Ankle = DF to PF
1st 45% - 6deg DF
2nd 55% - 12deg PF
