Gait I

Question 1

_____ is a series of rhythmic, alternating movements of the limbs and trunk which results in the forward progression of the center of gravity and may be analyzed in terms of its specific characteristics.

Answer 1

Normal gait

Question 2

Gait cycle begins when:

Answer 2

foot contacts the floor and ends with subsequent floor contact of the same foot

Question 3

Two major components of gait cycle:

Answer 3

stance phase and swing phase

A limb is in stance phase when it is in contact with the floor, and in swing phase when it is not in contact with the floor. l

Question 4

At normal walking speedstance occupies _____% of the gait cycle and swing accounts for _____% ,

Answer 4

60% stance

40% swing

Question 5

_____ is the linear distance between successive corresponding points of heel contact of the same foot

Answer 5

stride length

Question 6

_____ is the linear distance in the plane of progression between corresponding successive contact points of opposite feet

Answer 6

step length

Question 7

_____ refers to the period when only one limb is in contact with the floor

Answer 7

single support

Question 8

____ occurs when both feet are in contact with the floor simultaneously

Answer 8

double support.

Question 9

_____ distinguishes running from walking

Answer 9

elimination of double support

Question 10

As walking speed increases, there is relative decrease in time spent in _____ and corresponding increase in time spent in _____.

Answer 10

stance phase, swing phase

duration of double support decreases and finally disappears as walking speed continues to increase.

Question 11

Name the 5 discrete events that occur in stance phase

Answer 11

1. heel contact
2. foot flat
3. midstance point
4. heel-off
5. toe-off

Question 12

_____ is identified when the greater troch is in vertical alignment with the vertical bisector of the foot, as viewed in the sagittal plant

Answer 12

midstance point of stance phase

Question 13

____ refers to initial contact of the forefoot with the floor

Answer 13

foot-flat of stance phase

Question 14

Name the 3 sectors of stance phase and which of the 5 discrete events that occur in each.

Answer 14

weight acceptance - HC, FF
Midstance FF, MSP, HO
Push-off HO, TO

Question 15

Swing phase is divided into what 3 phases?

Answer 15

acceleration
midswing
deceleration

each constitute 1/3 of swing phase

Question 16

_____ is characterized by rapid forward acceleration of the lower end of the limb shortly after the toe leaves the floor

Answer 16

acceleration of swing phase

forward acceleration of the lower end of the limb shortly after the toes leave the floor

Question 17

____ is characterized by the swinging limb overtaking and moving ahead of the limb in stance phase

Answer 17

midswing

Question 18

_____ is characterized by the deceleration of the moving limb as it approaches the end of the interval

Answer 18

deceleration of swing phase

Question 19

Vertical displacement of COG:
Highest point:
Lowest point:

Answer 19

Highest: supporting limb is in midstance
Lowest: double support when both are in contact with the ground.

Question 20

Average change in vertical COG in adult male is _____

Answer 20

5cm (2 in)

Question 21

Total amount of side-to-side displacement of COG

Answer 21

5cm (2 in)

Question 22

Lateral limits of COG displacement are reached when?

Answer 22

as each supporting limb is at its midstance point

Question 23

How much of knee flexion occurs during stance phase

Answer 23

20 degrees begins at heel contact and continues during early part of stance phase.

Question 24

In normal walking the pelvis dips on ___ side and the stance hip ______ slightly.

Answer 24

swing phase side and stance hip adducts slightly.

Question 25

The amount of displacement of the pelvis from horizontal plane during pelvic dip does not exceed _____. In standing, this is known as ____ sign.

Answer 25

5 degrees trendelenburg sign - in walking it is a normal characteristic which serves to decrease the rise of the COG.

Question 26

In addition to dipping, the pelvis rotates forward in the _____ plane at approximately _____ degrees on the _____ side

Answer 26

horizontal plane 8 degrees swing phase side (4 degrees on each side of a center line)

Question 27

Benefit of pelvic rotation?

Answer 27

enables a slightly longer step length without further lowering of the COG, thus minimizing the total vertical displacement.

Question 28

_____ is the distance between the lines drawn through successive midpoints of heel contact of each foot

Answer 28

width of walking base.

Question 29

What is a normal width of walking base?

Answer 29

range from 5-10cm (2-4in)

Question 30

What minimizes the lateral displacement of COG with regard to width of walking base?

Answer 30

since the pelvis must shift toward the weight bearing side to maintain stability at midstance, the normally narrow walking base minimizes the lateral displacement of the COG

Question 31

____ of gait describes the motions of the body as a whole and the relative motions of the body parts during the different phases of gait

Answer 31

Kinematics example: study of angular relationships of the segments of the lower limb during walking cycle

Question 32

______ of gait describes the forces that produce or inhibit motion.

Answer 32

Kinetics

Question 33

Name the 4 forces which have the most significant influence on movements of the body in normal walking

Answer 33

1. Gravity 2. Muscular contraction 3. inertia 4. floor reaction (resultant of forces exerted by the floor on the foot) --- ground reaction force

Question 34

The force that the foot exerts on the floor, due to _____ and ____ is opposed by _____.

Answer 34

gravity and inertia ground reaction force (floor reaction)

Question 35

What keeps knee from buckling in ground reaction forces?

Answer 35

quad contraction - provides the necessary restraint so that the knee flexes at a controlled rate.

Question 36

The vertical force and horizontal force creates a _____ force that might cause the knee to buckle

Answer 36

resultant force -- due to a vertical and backward force so that it passes posterior to the knee axis.

Question 37

____ and ____ force are met by ____ and ____ at heel strike

Answer 37

gravity and inertia Vertical force and Horizontal force (VF + HF = Resultant force) - backward and upward.

Question 38

What is considered a normal cadence?

Answer 38

100 to 115 steps per minute slower or faster cadences have a pronounced effect on the values of joint angles, externally generated forces and muscular activity.

Question 39

In foot flat, the ankle joint is in ____ degrees of _____. by midstance it becomes ____

Answer 39

15 degrees of PF | 5 degrees of DF

Question 40

What prevents foot slap during heel contact

Answer 40

firing of the DF group (Tib ant, ext dig longus, and ext hall longus) as an eccentric contraction to provide enough force to prevent the forefoot from slapping against the ground as the external forces due to gravity and inertia drive the foot into plantar flexion

Question 41

What controls the rate at which the tibia rotates over the fixed foot as it moves from foot flat to midstance?

Answer 41

eccentric contraction of PF. ``` gastroc soleus tib posterior flex dig longus peroneus longus ```

Question 42

What causes the forward acceleration of the COG and also causes extension of the knee during midstance?

Answer 42

"push off" from the opposite limb so femur rotates forward on the tibia. There is also slowing of the tibial forward rotation by the increasingly active plantar flexors.