Week 1 Flashcards
(241 cards)
1
Q
What is gait?
A
The manner in which a person
walks
2
Q
What is a step?
A
From heel strike to next contralateral heel strike
3
Q
What is a stride?
A
From heel strike to next ipsilateral heel strike
4
Q
What is a cadence?
A
Number of steps taken per unit of time
5
Q
What is speed?
A
Rate of linear forward motion of the body
6
Q
How is step width found?
A
Linear distance between midpoint of heel of one foot and same point on other foot in completing a step
7
Q
What and how is step length found?
A
The linear distance between two successive points of contact of opposite extremities. Usually measured from the point of contact on one extremity to the point of one heel strike at the other extremity
8
Q
What is step duration?
A
The amount of time spent during a single step
9
Q
How long does a stride for a normal adult last?
A
1 secs
10
Q
What is the normal adult male cadence?
A
110/min
11
Q
What is the normal adult female cadence?
A
116/min
12
Q
When during cadence does the point of double limb support changes to running?
A
180/min
13
Q
What increases walking speed up to 120 steps/ min?
A
Increases in both cadence and stride length
14
Q
What increases walking speed for more than 120 steps/ min?
A
Increase in cadence
15
Q
What is a person’s normal comfortable speed of gait called?
A
Preferred Natural Self- Selected gait
16
Q
What is line of progression?
A
The path taken during gait
17
Q
What does the degree of toe- out represent and how is it found?
A
The angle of foot placement. Found by measuring the angle formed by each foot’s line of progression and the line intersecting the center of heel of the 2nd toe
18
Q
What is the normal angle of toe- out for men?
A
7 deg from the line of progression of each foot at free walking speed
19
Q
How does the angle of toe out decrease?
A
As the speed of walking increases
20
Q
One stride is = to _____
A
One complete gait cycle
21
Q
What are the periods in a complete gait cycle?
A
Stance period
Swing period
22
Q
62% of the gait cycle is what period?
A
Stance period.
23
Q
When does the stance period occur?
A
When the reference limb is in contact with the ground
24
Q
What part of the gait cycle is the swing period and when does it occur?
A
38%, which occurs when the reference limb is off the ground
25
What are the functional tasks of gait required for walking and what phase are they in?
- Weight Acceptance: Stance
- Single Limb Support: Stance
- Swing Limb Advancement: Swing
26
What is the 1st and most challenging task in the gait cycle and why?
Weight acceptance. It is the most difficult, because it has 3 requirements
27
What are the requirements of weight acceptance?
- Preservation of forward progression
- Initial limb stability
- Shock absorption
28
What is the challenge of weight acceptance?
The abrupt transfer of body weight unto a limb that has just finished swinging forward and has an unstable alignment
29
What accomplishments are needed for
| Single Limb Support?
Stability and forward progression
30
What accomplishments are needed for
| Swing Limb Advancement?
Foot clearance and limb advancement
31
What are the phases of the gait cycle, what period and functional task do they fall under?
- Initial Contact: Stance: Weight acceptance
- Loading Response: Stance: Weight acceptance
- Mid Stance: Stance: Single Limb
Support
- Terminal Stance: Stance: Single Limb
Support
- Pre Swing: Swing: Swing Limb
Advancement
- Initial Swing: Swing: Swing Limb
Advancement
- Mid Swing: Swing: Swing Limb
Advancement
- Terminal Swing: Swing: Swing Limb
Advancement
32
What is initial contact?
Moment when the foot contacts the ground and the immediate reaction to the onset of body weight transfer. 0%
33
What are the critical events that occur during initial contact?
* Heel first contact
* Initiation of heel rocker
* Impact Deceleration
34
What is loading response?
Period of double limb support, where weight rapidly transferred onto
outstretched limb as foot contact transitions from the heel to flat on the floor. 0-12%
35
What are the critical events that occur during loading response?
* Progression of heel rocker
* Restrained ankle plantar flexion
* Restrained knee flexion
* Sustained hip flexion
36
What is mid stance?
1st half of single limb support, where the body progresses over a single, stable limb with a stationary foot until the weight of the body is aligned over the forefoot of the reference limb. 12-31%
37
What are the critical events that occur during mid stance?
* Ankle rocker
* Restrained ankle dorsiflexion
* Restrained knee extension
* Frontal plane hip stabilization
38
What is Terminal Stance (TSt)?
2nd half of single limb support, where the body moves ahead of limb and weight is transferred to forefoot and the heel of the stance limb begins to rise off the ground. 31-50%
39
What are the critical events of Terminal Stance (TSt)?
* Initiation of forefoot rocker
* Controlled ankle dorsiflexion with heel rise
* Trailing limb posture
* Free forward fall of the body
40
What is Pre-Swing (PSw)?
Rapid unloading of limb occurs as weight is transferred to contralateral limb. Begins with initial contact of the contralateral limb and progresses until toe off of the reference limb. 2nd period of double limb support. 50-62%
41
What are the critical events of Pre-Swing (PSw)?
* Adequate knee flexion
| * Adequate ankle plantar flexion
42
What is Initial Swing (ISw)?
Thigh begins to advance as the foot comes up off the floor and ends when the reference foot opposite of the stance foot. 62-75%
43
What are the critical events of Initial Swing (ISw)?
* Adequate knee flexion
| * Adequate hip flexion
44
What is Mid-Swing (MSw)?
Thigh continues to advance as the knee begins to extend and the foot clears the ground. Concludes when the tibia of the swinging limb aligns vertically. 75-87%
45
What are the critical events of Mid-Swing (MSw)?
* Adequate hip flexion
| * Adequate ankle dorsiflexion
46
What is Terminal Swing (TSw)?
Knee extends as the limb prepares for contact with the ground. 87-100%
47
What are the critical events of Terminal Swing (TSw)?
* Deceleration and inhibition of hip flexion
* Deceleration at the knee
* Adequate knee extension
* Adequate ankle dorsiflexion
48
What happens in the other limb while the reference limb is going through Initial contact and loading response?
Pre-Swing
49
What happens in the other limb while the reference limb is going through Mid-Stance?
- Initial swing
| - 1st half of Mid- swing
50
What happens in the other limb while the reference limb is going through terminal-Stance?
- 2nd half of mid swing
| - Terminal Swing
51
What happens in the other limb while the reference limb is going through Pre-Swing?
- Initial Contact
| - Loading Response
52
What happens in the other limb while the reference limb is going through Initial Swing and 1st half of mid- swing?
Mid stance
53
What happens in the other limb while the reference limb is going through the 2nd half of mid- swing and terminal swing?
Terminal stance
54
What biomechanical factors should we
| consider during gait?
- Range of Motion
- Torque Demands
- Muscle Activity
- Functional Significance
55
Which are the kinematic variables of the biomechanical factors we should consider during gait?
Range of Motion
56
Which are the kinetic variables of the biomechanical factors we should consider during gait?
- Torque Demands
| - Muscle Actions
57
What creates the torque demands at the
| joints during gait?
- External torque
- Gravitational torque
- Intersegmental torque
- Muscle torque
58
What creates the external torque?
Vertical ground reaction force vector
59
What are kinematics?
A set of concepts that allows us to describe the motion of the body and or its segments, without regard to the forces causing the movement described
60
What are kinetics?
A set of concepts that deals with forces that produce, stop and modify motions of either the body as a whole or the individual body segments
61
What is the 1st peak in vertical ground reaction force equal to in the gait cycle?
Weight acceptance, when the body's downward velocity is being slowed. (Loading response)
62
What is the 2nd peak in vertical ground reaction force equal to in the gait cycle?
Push off, which shows that the body's CoM is being accelerated upward to increase its upward velocity. (Terminal stance)
63
Where is the vertical ground reaction force vector found?
Just anterior to the knee joint
64
How do anteroposterior ground reaction
| forces vary during the 1st half of the stance phase of gait?
The ground reaction force is directed posteriorly against the foot that is initially contacting the ground and prevents the foot from moving forward. Mx magnitude is 20% of boy weight
65
When is the anteroposterior ground reaction
| forces neutral during the stance phase of gait?
Mid stance
66
How do anteroposterior ground reaction
| forces vary during the 2nd half of the stance phase of gait?
The vector is directed anteriorly against the foot, enabling the person to push off
67
What is the center of pressure?
The single point on the foot which the resultant surface pressure may be considered to the acting. The starting point for the ground reaction force vector
68
What is the progression of center of pressure during barefoot walking?
Starts at the posterolateral edge of the heel at the beginning of the stance phase. Moves in a linear and medial manner through the mid foot area all the way to the 1st and 2nd toes during light stance
69
What creates the intersegmental torque?
A result from the angular accelerations and angular velocities of other segments of the system
70
What creates the muscle torque?
The combined action of all MSK elements acting on the joint
71
What muscle torques combine in successful gait?
Hip and knees(net extensor torque) at the beginning and progresses to ankle plantar flexors(net flexor torque)
72
What are the induced torques?
* External
* Gravitational
* Intersegmental
73
What are the reactionary torques?
• Muscle torque
74
How are torques balanced for success in gait?
Induced and reactionary torques must be balanced
75
During Initial Contact, what is happening
| at the ankle joint in regards to ROM?
Neutral position
76
During Initial Contact, what is happening
at the ankle joint in regards to Torque
Demand?
Plantar flexion torque
77
During Initial Contact, what is happening
at the ankle joint in regards to muscle
action?
Isometric contraction of pre-tibial muscles
78
During Initial Contact, what is happening
at the ankle joint in regards to functional
significance?
Foot correctly positioned for heel rocker action in LR
79
During Initial Contact, what is happening
| at the knee joint in regards to ROM?
Positioned in neutral to 5 degrees flexed
80
During Initial Contact, what is happening
at the knee joint in regards to Torque
Demand?
Brief extension torque
81
During Initial Contact, what is happening
at the knee joint in regards to muscle
action?
* Quadriceps prep for next phase
| * Hamstrings counter extension torque
82
During Initial Contact, what is happening
at the knee joint in regards to functional
significance?
Extension torque stabilizes the knee
83
During Initial Contact, what is happening
| at the hip joint in regards to ROM?
• Flexed 20 degrees
84
During Initial Contact, what is happening
at the hip joint in regards to Torque
Demand?
Rapid, high intensity flexion torque begins
85
During Initial Contact, what is happening
at the hip joint in regards to muscle
action?
* All hip extensors active
| * Semimembranosis and bicep femoris long head activity wanes
86
During Initial Contact, what is happening
at the hip joint in regards to functional
significance?
Hip in position of forward reach
87
During Initial Contact, what is happening
| with the pelvis?
In 5 degrees of forward rotation in the horizontal plane
88
During Loading Response, what is
| happening at the ankle joint in regards to ROM?
5 degrees of rapid plantar flexion
89
During Loading Response, what is
| happening at the ankle joint in regards to torque demand?
Plantar flexion torque forces foot
| to floor then diminishes
90
During Loading Response, what is
| happening at the ankle joint in regards to muscle action?
* Pretibials contract eccentrically
| * Soleus and gastrocnemius act to control tibial advancement
91
During Loading Response, what is
| happening at the ankle joint in regards to functional significance?
* Heel rocker action created
* Momentum carried forward
* Knee flexion initiated
92
What does the heel rocker action
| provide?
Facilitates forward progression
| of the entire stance limb
93
During Loading Response, what is
| happening at the subtalar joint in regards to ROM?
* Calcaneus everts 5 degrees
| * Subtalar joint pronates
94
During Loading Response, what is
| happening at the subtalar joint in regards to torque demand?
Eversion torque
95
During Loading Response, what is
| happening at the subtalar joint in regards to muscle action?
Both anterior and posterior tibialis muscles contract eccentrically
96
During Loading Response, what is
| happening at the subtalar joint in regards to functional significance?
• Assists shock absorption
• Induces IR of tibia which reduces
rotatory stress on ankle
97
During Loading Response, what is
| happening at the knee joint in regards to ROM?
Moves to 15 degrees of flexion
98
During Loading Response, what is
| happening at the knee joint in regards to torque demand?
Rapid, moderate intensity flexion torque
99
During Loading Response, what is
| happening at the knee joint in regards to muscle action?
* Eccentric quadriceps activity
| * Diminishing hamstring activity
100
During Loading Response, what is
| happening at the knee joint in regards to functional significance?
* Shock absorbed
| * Limb stability maintained
101
During Loading Response, what is
| happening at the hip joint in regards to ROM?
Remains in 20 degrees of flexion
102
During Loading Response, what is
| happening at the hip joint in regards to torque demand?
* Rapid, high intensity flexion torque present
| * Adduction torque begins
103
During Loading Response, what is
| happening at the hip joint in regards to muscle action?
Hip extensors and abductors active
104
During Loading Response, what is
| happening at the hip joint in regards to functional significance?
Hip joint, pelvis, and trunk stabilized in sagittal and frontal planes
105
During Loading Response, what is
| happening with the pelvis?
Remains in 5 degrees of forward rotation in
| the horizontal plane
106
What are the pre- tibial muscles?
Anterior tibialis, Extensor hallucis longus, and extensor digitorum longus
107
During Mid-Stance, what is happening at
| the ankle joint in regards to ROM?
Moves into 5 degrees of dorsiflexion
108
During Mid-Stance, what is happening at
| the ankle joint in regards to torque demand?
Markedly increasing dorsiflexion torque
109
During Mid-Stance, what is happening at
| the ankle joint in regards to muscle action?
Soleus and gastrocnemius contract eccentrically to control forward progression of tibia
110
During Mid-Stance, what is happening at
| the ankle joint in regards to functional significance?
* Calf muscles stabilize knee
* Ankle rocker action created
* Body progresses forward
111
What does the ankle rocker action provide?
Ankle becomes fulcrum for continued progression of limb over stationary foot
112
During Mid-Stance, what is happening at
| the subtalar joint in regards to ROM?
Eversion position remains relatively unchanged from end of Loading Response
113
During Mid-Stance, what is happening at
| the subtalar joint in regards to torque demand?
Eversion torque diminishes
114
During Mid-Stance, what is happening at
| the subtalar joint in regards to muscle action?
Posterior tibialis, soleus, and peroneals all eccentrically active
115
During Mid-Stance, what is happening at
the subtalar joint in regards to functional
significance?
Control of eversion
116
During Mid-Stance, what is happening at
| the knee joint in regards to ROM?
Extends to 5 degrees flexed
117
During Mid-Stance, what is happening at
| the knee joint in regards to torque demand?
Extension torque
118
During Mid-Stance, what is happening at
| the knee joint in regards to muscle action?
* Quadriceps stabilize knee until knee extension torque begins
* Calf muscles restrain tibia
119
During Mid-Stance, what is happening at
the knee joint in regards to functional
significance?
Knee stability maintained by knee extension torque and calf muscle activity
120
During Mid-Stance, what is happening at
| the hip joint in regards to ROM?
Extension to neutral
121
During Mid-Stance, what is happening at
| the hip joint in regards to torque demand?
* Change from flexion to extension torque
| * Adduction torque continues
122
During Mid-Stance, what is happening at
| the hip joint in regards to muscle action?
* No hip muscle activity in sagittal plane
| * Hip abductors active
123
During Mid-Stance, what is happening at
the hip joint in regards to functional
significance?
* Stable hip joint position achieved in sagittal plane
| * Pelvis stabilized in frontal plane
124
During Mid-Stance, what is happening with the pelvis?
Rotates backward in horizontal
| plane to neutral
125
During Terminal Stance, what is happening at the ankle joint in regards to ROM?
Moves into 10 degrees of dorsiflexion
126
During Terminal Stance, what is happening at the ankle joint in regards to torque demand?
Dorsiflexion torque peaks
127
During Terminal Stance, what is happening at the ankle joint in regards to muscle action?
Calf muscle activity peaks
128
During Terminal Stance, what is happening at the ankle joint in regards to functional significance?
* Maximal forward progression of the tibia
| * Heel allowed to rise
129
During Terminal Stance, what is
| happening at the subtalar joint in regards to ROM?
Progressive reduction of eversion to approximately 2 degrees of eversion
130
During Terminal Stance, what is
| happening at the subtalar joint in regards to torque demand?
Inversion torque created as heel rises
131
During Terminal Stance, what is
| happening at the subtalar joint in regards to muscle action?
* Posterior tibialis and soleus contract concentrically
| * Peroneals isometrically active
132
During Terminal Stance, what is
| happening at the subtalar joint in regards to functional significance?
Reduction in eversion increases stability of midtarsal joint
133
During Terminal Stance, what is happening at the MTP joints in regards to ROM?
Move into 30 degrees of extension
134
During Terminal Stance, what is happening at the MTP joints in regards to torque demand?
Extension torque created
135
During Terminal Stance, what is happening at the MTP joints in regards to muscle action?
* Calf muscle activity peaks
| * Posterior tibialis and soleus contract concentrically
136
During Terminal Stance, what is happening at the MTP joints in regards to functional significance?
* Forefoot rocker action created
| * Contributes to contralateral step length
137
What does the forefoot rocker action provide?
Metatarsal heads serve to facilitate continued forward progression of tibia
138
During Terminal Stance, what is happening at the knee joint in regards to ROM?
Unchanged from Mid-Stance in 5 degrees of flexion
139
During Terminal Stance, what is happening at the knee joint in regards to torque demand?
Extension torque peaks and then diminishes
140
During Terminal Stance, what is happening at the knee joint in regards to muscle action?
* Calf muscles continue to stabilize knee by restraining tibia
* Biceps femoris may be active
141
During Terminal Stance, what is happening at the knee joint in regards to functional significance?
* Joint stability maintained
| * Biceps femoris may act to prevent hyperextension
142
During Terminal Stance, what is
| happening at the hip joint in regards to ROM?
Thigh moves to trailing position of 20 degrees of extension
143
During Terminal Stance, what is
| happening at the hip joint in regards to torque demand?
* Hip extension torque
| * Adduction torque rapidly diminishes
144
During Terminal Stance, what is
| happening at the hip joint in regards to muscle action?
* Posterior fibers of TFL cease
| * Anterior fibers of TFL may become active
145
During Terminal Stance, what is
| happening at the hip joint in regards to functional significance?
Body allowed to advance past foot to maximize step length while limb remains stable
146
During Terminal Stance, what is happening with the pelvis?
Anterior tilt and 5 degrees backward rotation in horizontal plane
147
During Pre-Swing, what is happening at
| the ankle joint in regards to ROM?
Moves into 15 degrees of plantar flexion
148
During Pre-Swing, what is happening at
| the ankle joint in regards to torque demand?
Dorsiflexion torque rapidly decreases
149
During Pre-Swing, what is happening at
| the ankle joint in regards to muscle action?
* Calf muscle activity ceases
| * Pretibial muscle activity initiated
150
During Pre-Swing, what is happening at
| the ankle joint in regards to functional significance?
* Forefoot on floor assists balance
| * Plantar flexion assists knee flexion and limb advancement
151
During Pre-Swing, what is happening at
| the subtalar joint in regards to ROM?
Achieves neutral position
152
During Pre-Swing, what is happening at
| the subtalar joint in regards to torque demand?
Inversion torque diminishes to zero
153
During Pre-Swing, what is happening at
| the subtalar joint in regards to muscle action?
Anterior tibialis begins to contract
154
During Pre-Swing, what is happening at
| the subtalar joint in regards to functional significance?
Preparation for foot clearing the ground during swing
155
During Pre-Swing, what is happening at
| the MTP joints in regards to ROM?
Move into 60 degrees of extension
156
During Pre-Swing, what is happening at
| the MTP joints in regards to torque demand?
Extension torque rapidly decreases
157
During Pre-Swing, what is happening at
| the MTP joints in regards to muscle action?
Calf muscle activity ceases
158
During Pre-Swing, what is happening at
| the MTP joints in regards to functional significance?
Forefoot on floor assists balance
159
During Pre-Swing, what is happening at
| the knee joint in regards to ROM?
Rapidly flexes to 40 degrees
160
During Pre-Swing, what is happening at
| the knee joint in regards to torque demand?
Flexion torque demand
161
During Pre-Swing, what is happening at
| the knee joint in regards to muscle action?
* Minimal knee flexor activity from gracilis
| * Rectus femoris may be active
162
During Pre-Swing, what is happening at
| the knee joint in regards to functional significance?
* Contributes to knee flexion
| * Rectus femoris may restrain speed of knee flexion
163
During Pre-Swing, what is happening at
| the hip joint in regards to ROM?
Thigh flexes forward by falling to position of 10 degrees of extension
164
During Pre-Swing, what is happening at
| the hip joint in regards to torque demand?
Hip extension torque diminishes
165
During Pre-Swing, what is happening at
| the hip joint in regards to muscle action?
* Adductor longus contracts concentrically
| * Rectus femoris may be active
166
During Pre-Swing, what is happening at
| the hip joint in regards to functional significance?
* Limb advancement begins
| * Hip flexion motion contributes to knee flexion
167
During Pre-Swing, what is happening
| with the pelvis?
Remains in 5 degrees of backward rotation in horizontal plane
168
During Initial Swing, what is happening
| at the ankle joint in regards to ROM?
Moves into 5 degrees of plantar flexion
169
During Initial Swing, what is happening
| at the ankle joint in regards to torque demand?
Very low level plantar flexion torque
170
During Initial Swing, what is happening
| at the ankle joint in regards to muscle action?
Pretibial muscles contract concentrically to initiate dorsiflexion
171
During Initial Swing, what is happening
| at the ankle joint in regards to functional significance?
Dorsiflexion needed to clear foot in next phase begins
172
During Initial Swing, what is happening
| at the subtalar joint in regards to ROM?
Maintains neutral position
173
During Initial Swing, what is happening
| at the subtalar joint in regards to torque demand?
None to very slight inversion torque
174
During Initial Swing, what is happening
| at the subtalar joint in regards to muscle action?
Anterior tibialis stabilizes medially
175
During Initial Swing, what is happening
| at the subtalar joint in regards to functional significance?
Foot positioned to clear the ground
176
During Initial Swing, what is happening
| at the MTP joints in regards to ROM?
Flexion to neutral position and maintained there throughout swing
177
During Initial Swing, what is happening
| at the MTP joints in regards to torque demand?
Flexion torque which quickly decreased
178
During Initial Swing, what is happening
| at the MTP joints in regards to muscle action?
EHL and EDL peak in activity
179
During Initial Swing, what is happening
| at the MTP joints in regards to functional significance?
Toes stabilized allowing EHL and EDL to facilitated dorsiflexion at ankle
180
During Initial Swing, what is happening
| at the knee joint in regards to ROM?
Further rapid flexion to 60 degrees
181
During Initial Swing, what is happening
| at the knee joint in regards to torque demand?
Knee flexion torque
182
During Initial Swing, what is happening
| at the knee joint in regards to muscle action?
Peak in activity of biceps femoris short head, sartorius, and gracilis
183
During Initial Swing, what is happening
| at the knee joint in regards to functional significance?
Foot clears floor as thigh begins to advance
184
During Initial Swing, what is happening
| at the hip joint in regards to ROM?
Moves to position of 15 degrees of flexion
185
During Initial Swing, what is happening
| at the hip joint in regards to torque demand?
Hip extension torque initial which approaches zero by end of phase
186
During Initial Swing, what is happening
| at the hip joint in regards to muscle action?
Iliacus, gracilis, sartorius, and adductor longus active
187
During Initial Swing, what is happening
| at the hip joint in regards to functional significance?
Limb advancement continues
188
During Initial Swing, what is happening
| with the pelvis?
Remains in 5 degrees of backward rotation in horizontal plane
189
During Mid-Swing, what is happening at
| the ankle joint in regards to ROM?
Dorsiflexion to neutral
190
During Mid-Swing, what is happening at
| the ankle joint in regards to torque demand?
Very low level of plantar flexion torque
191
During Mid-Swing, what is happening at
| the ankle joint in regards to muscle action?
Pretibial muscles contract concentrically
192
During Mid-Swing, what is happening at
| the ankle joint in regards to functional significance?
Foot clears the ground by 1 centimeter
193
During Mid-Swing, what is happening at
| the subtalar joint in regards to ROM?
Maintains neutral position
194
During Mid-Swing, what is happening at
| the subtalar joint in regards to torque demand?
None to very slight inversion torque
195
During Mid-Swing, what is happening at
| the subtalar joint in regards to muscle action?
Anterior tibialis stabilizes medially
196
During Mid-Swing, what is happening at
| the subtalar joint in regards to functional significance?
Foot positioned to clear the ground
197
During Mid-Swing, what is happening at
| the knee joint in regards to ROM?
Rapidly extends to 25 degrees of flexion
198
During Mid-Swing, what is happening at
| the knee joint in regards to torque demand?
Transition to knee extension torque late in phase
199
During Mid-Swing, what is happening at
| the knee joint in regards to muscle action?
* Short head of biceps femoris may control rate of extension
| * Hamstrings active late in phase
200
During Mid-Swing, what is happening at
| the knee joint in regards to functional significance?
Extension necessary for step length begins in this phase
201
During Mid-Swing, what is happening at
| the hip joint in regards to ROM?
Moves to position of 25 degrees of flexion
202
During Mid-Swing, what is happening at
| the hip joint in regards to torque demand?
Gradually increasing hip flexion torque
203
During Mid-Swing, what is happening at
| the hip joint in regards to muscle action?
Hamstrings become active late in phase
204
During Mid-Swing, what is happening at
| the hip joint in regards to functional significance?
* Thigh advancement slows
| * Momentum of swing limb helps carry body past stance limb
205
During Mid-Swing, what is happening with the pelvis?
Rotates forward in horizontal plane to neutral
206
During Terminal Swing, what is
| happening at the ankle joint in regards to ROM?
Remains in neutral
207
During Terminal Swing, what is
| happening at the ankle joint in regards to torque demand?
Plantar flexion torque diminishes to zero
208
During Terminal Swing, what is
| happening at the ankle joint in regards to muscle action?
Pretibial muscles contract isometrically
209
During Terminal Swing, what is
| happening at the ankle joint in regards to functional significance?
Neutral position assures heel contact for Initial Contact
210
During Terminal Swing, what is
| happening at the subtalar joint in regards to ROM?
Maintains neutral position
211
During Terminal Swing, what is
| happening at the subtalar joint in regards to torque demand?
None to very slight inversion torque
212
During Terminal Swing, what is
| happening at the subtalar joint in regards to muscle action?
Anterior tibialis stabilizes medially
213
During Terminal Swing, what is
| happening at the subtalar joint in regards to functional significance?
Foot positioned for heel contact
214
During Terminal Swing, what is
| happening at the knee joint in regards to ROM?
Extends to neutral, but then may move into 5 degrees of flexion
215
During Terminal Swing, what is
| happening at the knee joint in regards to torque demand?
Extension torque
216
During Terminal Swing, what is
| happening at the knee joint in regards to muscle action?
* Quadriceps active concentrically
| * Hamstrings peak in activity
217
During Terminal Swing, what is
| happening at the knee joint in regards to functional significance?
Step length optimized by leg reaching out
218
During Terminal Swing, what is
| happening at the hip joint in regards to ROM?
Falls slightly to position of 20 degrees of flexion
219
During Terminal Swing, what is
| happening at the hip joint in regards to torque demand?
Hip flexion torque diminishes at end of phase
220
During Terminal Swing, what is
| happening at the hip joint in regards to muscle action?
Hamstrings, adductor magnus, gluteus maximus, gluteus medius and TFL active
221
During Terminal Swing, what is
| happening at the hip joint in regards to functional significance?
Limb positioned for heel first initial contact
222
During Terminal Swing, what is happening with the pelvis?
Rotates forward 5 degrees in the horizontal
| plane
223
What happens through the trunk during
| the gait cycle?
• Trunk rotation occurs opposite to direction of rotation of pelvis
• Arm swing follows pattern such that opposite upper and lower extremities
swing forward concurrently during gait
224
What happens during the initiation of
| gait?
• Normally, no changes in pattern of events with either right or left lower extremity
• Trend for smaller displacements and lover
velocities with age
• Starts with bilateral inhibition of plantar flexors (gastroc-soleus) and activation of dorsiflexors(ant tib)
• Center of pressure shifts posteriorly and briefly toward swing foot, then toward stance
foot heel, stance foot forefoot and, ultimately, medial forefoot of stance foot
225
What happens during the termination of
| gait?
* Sequence of events that occurs when normal gait begins to change in progression toward stopping
* Push-off reduced in stance limb
* Swing limb provides braking forces at initial contact
226
How does treadmill walking differ from
| walking across the ground?
• Higher cadence and shorter stance times with treadmill walking at comparable speeds
• Push-off forces and maximal ground reaction forces generally lower with treadmill
walking
• Unclear whether metabolic costs are different
227
How does muscle function differ in
| running as compared to walking?
```
• Little difference in sequence of muscle
activation patterns during walking and
running
• Magnitude of muscle contraction forces
greater in running
```
228
What is the functional limb varus angle?
Angle between the bisection of the lower leg and the ground
229
What is the difference between the functional limb varus in walking vs. running?
Increases during running as compared to walking
230
What is responsible for the difference in functional limb varus during walking vs. runnning?
Associated with increased demands during running in vertical, anteroposterior and
mediolateral directions
231
Why is greater balance required for running?
The lack of double- limb support
232
What is the typical BoS in walking?
2.5
233
What are the phases in the stance period of stair gait?
- Weight acceptance
- Pull up
- Forward continuous
234
What are the phases in the swing period of stair gait?
- Foot clearance
| - Foot placement
235
Where on the foot is initial contact during stair gait?
On the forefoot
236
What are the muscles whose concentric contraction is primarily responsible for stair ascent?
Rectus femoris, vastus lateralis, soleus, and medial gastroc
237
What are the muscles whose eccentric contraction is primarily responsible for stair descent?
The same muscles that involve energy absorption
238
When does the maximum peak internal abductor moment at the hip occur?
When descending stairs
239
What are essential for successful achievement of single limb support?
Stability and forward progression
240
What is external torque?
Torque that peaks during weight acceptance when body’s downward velocity is being slowed
241
What is gravitational torque?
Results from the force of gravity acting upon the center of mass of a body segment
