Walking and gait

Question 1

what is location

Answer 1

ability to move from one place to another

Question 2

how is walking chracterised

Answer 2

‘inverted pendulum‘ motion, in which the body vaults over the non-moving limb.a repeated gait cycle.

Question 3

what are the diferent stages of the gait cycle and how are they charaterised

Answer 3

Stance phase: Accounts for 60% of the gait cycle. It can be divided into the heel strike, support and toe-off phases. from the time the heel strikes
until the toe of the same foot begins
to lift the off the ground
Swing phase: Accounts for 40% of the cycle. It can be divided into the leg lift and swing phases. the limb has ost contact with the ground

Question 4

advatanges of locomation

Answer 4

frees our hands, elevates our
head, and allows us to move on challenging
terrain

Question 5

disadvantages of locomation

Answer 5

Disadvantages: poses a biomechanical

challenge (efficiency and stability).

Question 6

walking pattern of gait

Answer 6

Having one foot on the ground

at all times.

Question 7

running pattern of gait

Answer 7

At some point during gait
both feet are off the ground
simultaneously.
Absorbing and releasing
energy stored in tendons
biomechanically makes
running a series of
controlled leaps

Question 8

When most skeletal muscles contract the
bones to which they are attached rotate
around a joint what is this rotational force

Answer 8

is the

torque

Question 9

what are Agonists and antagonists:

Answer 9

agonists cause a movement through their
own contraction, antagonists oppose a
movement

Question 10

what are synergist muscles

Answer 10

Perform or help to perform the same

motion as the agonist

Question 11

what happens if mucle lenghths shortsen what is it called

what about when it lenghthens

Answer 11

If a muscle length shortens – concentric

If a muscle length increases - eccentric

Question 12

what is a muscle lever

Answer 12

A muscle lever (moment)
arm is the perpendicular
distance to the point of
rotation (the joint) from
the line of muscle action

Question 13

what can affect the efficienc of locomation and the pattern of gait

Answer 13

Alterations to the
structure of the
musculoskeletal system
will affect the efficiency
of locomotion and the
pattern of gait.

Question 14

what are tendons

Answer 14

Tendons are a tough band of
connective tissue
Connect muscle to bone
Build to endure tension

Question 15

how are tendons and ligements different

Answer 15

ligaments join one bone to

another

Question 16

what provides the brain with infromation about body postion and mvement?

Answer 16

Receptors in muscles and joints
provide the brain with
information about body position
and movement

Question 17

3roles of the cereebellum

Answer 17

Cerebellum: Motor correction –
adjusting movement based on
sensory and proprioceptive input
Motor learning- improving
performance of motor sequence
with repetition
Balance- coordinating muscle
systems across the body

Question 18

what are the challenges of bipedal locomotion

Answer 18

Gravity and Efficiency:
Gravity acts at the centre of mass (CoM ) of each body segment and may cause
gravitational moments depending on how the limb is positioned. The size of this downward force is a product of our mass and the acceleration of
gravity.
Stability:
Challenges of Bipedal Locomotion
The human bodies CoM is positioned
within the pelvis, in the mid-line anterior
to the second sacral vertebra Stability of a body is determined by the
relationship between the BoS (Base of
support) and the position of the total body
CoM.The body maybe technically unstable but not fall provided it is moving towards a
stable solution. Ankle strategy and Hip strategy. Humans require little energy expenditure during bipedal posture (pendulum).

Question 19

what are the conditons that alter gait and how

Answer 19

Structural damage:
Normal locomotion requires nervous
system, blood supply, skeleton, joints,
muscles and tendons: damage to any of
these structures can affect locomotion
Aging:
There are normal changes in gait with aging due to
decreased muscle bulk and flexibility: stride length
is reduced and walking becomes slower. To walk
faster, the number of steps taken is increased rather
than increasing the stride length. 
Footware:
flip-flops: wearers take shorter steps and
heels hit the ground with less vertical
force. Toes are not brought up as much,
creating a larger ankle angle and shorter
stride length.
High heals: The shoe's elevated heel
shortens the Achilles tendon and
accompanying shortening of the calf
muscles. 
Arthritis, inflammatory or
degenerative conditions:
may cause pain and decrease
mobility of a joint. Rheumatoid
arthritis, infectious arthritis,
osteoarthritis, gout and pseudogout
and common causes of limp
Neurological disorders:
Individuals with Parkinson’s
Disease walk slowly and rigidly
with small, shuffling steps.

Question 20

what are the gait abnormalityies

Answer 20

Antalgic Gait:
Any gait that reduces loading on the affected extremity by decreasing stance
phase time or joint forces as to avoid pain on weight-bearing structures.
Examples: “stone in your shoe”, diabetic foot, osteoarthritis, gout, joint or limb
deformity, ingrown toenail, and trauma.
Painful side:
A shortened stance phase time
Lengthen swing phase time
Lengthen step length

Question 21

what are the pathological gaits

Answer 21

Ataxic gait (cerebellar gait):
unsteady, uncoordinated walk, a
wide base and the feet thrown out,
coming down on the heel and then
on the toes, double tap. Multiple
sclerosis, cerebellar diseases.
Parkinsonian Gait: patient involuntarily
moves with short, accelerating steps,
often on tiptoe, with the trunk flexed
forward and the legs flexed stiffly at the
hips and knees. Parkinson's disease and
conditions that affect the basal ganglia 
Myopathic gait (Waddling gait ): With
muscular diseases, the proximal pelvic
girdle muscles are usually weak. The
pelvis is not stabilised as leg is lifted
to step forward, pelvis tilts toward the
non-weight bearing leg, waddle type
of gait.
Neuropathic Gait (High stepping gait):
Seen in peripheral nerve disease, the
distal lower extremity is most affected.
Because the foot dorsiflexors are
weak, patient has a high stepping gait
in an attempt to avoid dragging the toe.

Question 22

desribe the morphological adaptatinos to human bipedalism - balancing

Answer 22

The supporting rectangle of quadrupedal
primates is much greater than that of bipedal
humans
In standing upright it is essential that the
body’s centre of gravity remains directly over
the supporting rectangle

Question 23

desribe the morphological adaptatinos to human bipedalism -pelvis and hip

Answer 23

The human pelvis is
shortened vertically and
expanded both laterally
and anteroposteriorly.
Uniquely, the human ilium
is wider than it is high: the
reduced height brings the
sacroiliac joint closer to
the hip joint, reducing the
stress on the ilium caused
by transmitting the weight
of the body from the
vertebral column to the hip
joint. 
The human iliac blade is
curved and mediallyorientated,
bringing the small
gluteal muscles into a position
where they can act as
abductors of the thigh.
The abductors support the
pelvis when the body weight is
on one leg and prevent side-toside
swaying of the trunk
during walking.
Other thigh abductors are tensor fascia latae, sartorius, piriformis, obturator
internus but these do not have the important weight-bearing role of the small
glutea

Question 24

desrbie the trendeleburg gait

Answer 24

ay prevent effective functioning
of the small gluteals, leading to a
characteristic gait called
Trendelenburg gait.
When the good limb enters swing
phase, its side of the pelvis drops
because the small gluteals on the
opposite side cannot hold the
pelvis level.
To prevent a fall, the lumbar spine
will be flexed towards the
paralyzed side, bringing the
centre of gravity of the trunk over
the foot in stance phase.

Question 25

desribe the morphological adaptatinos to human bipedalism:femur

Answer 25

The femoral head in humans is larger
than those of apes: an adaptation to load
bearing.
The diagonal disposition of the femur
re-centers support directly inferior to the
trunk (body mass) to make bipedal
standing more efficient and to enable
bipedal walking.

Question 26

what are coxa vara and valga

Answer 26

Coxa vara Decreased angle (< than 120°) of the
femoral neck. Causes a mild
shortening of the lower limb and
limits passive abduction of the hip.
May result in a ‘duck waddle gait’

Coxa valga Increased angle (> than 140°). Results
from weakness of the abductor muscles
and lack of normal weight-bearing forces.
Associated with neuromuscular disorders
such as cerebral palsy and poliomyelitis.

Question 27

what is teh nromal angle of teh femooral neck

Answer 27

125 degrees

Question 28

how do people get coxa vara and coxa valga?

Answer 28

Can be congenital or acquired by defective ossification. It may also change with any pathological process that weakens the neck of the femur (e.g. rickets).

Question 29

how does the knee ensure stability

Answer 29

knee has a ‘locking
mechanism’, enabling it to stabilize in a
fully extended position.

Stability is ensured: the femoral and tibial
condyles are in their most close-packed
position, the anterior cruciate ligament is
tensed, the collateral ligaments are tensed

Question 30

which muscles allows gthe knee to extend against gravity

Answer 30

Quadriceps
femoris extends
the knee against
gravity

Question 31

how can the anterior cruciate ligamaent be torn

Answer 31

Deceleration or rotational forces acting on the weightbearing
limb

Question 32

what prevents the trunk rotating backwards at
the hip joint.
what does the verterbral curve aid in

What are the secondary cervical and lumbar curves useful for

Answer 32

Tension of the iliofemoral ligament
prevents the trunk rotating backwards at
the hip joint.

The vertebral curves ‘cancel out’,
passing weight directly to the lower
limb.

Secondary cervical and lumbar
curves are important in balancing body
weight over the feet.

Question 33

Describe the arch of the foot (1)

What does the arch of the foot allow for? (2)

Answer 33

Humans have a two-part longitudinal arch (one medial, one lateral).

Permit
medial weight transfer during midstance, act as a ‘shock absorber’ against forces
generated during locomotion
Distribute body weight over the sole of the foot
during standing.

Question 34

how can things go wrong in the foot:

1) give example
2) what is a key factor
3) who is prone

Answer 34

Fallen arches occur in
many people

Behaviour is often
a key factor

Overweight individuals
who stand for long periods of time
may be particularly prone.

Question 35

what happens in stance phase and swing phase

Answer 35

Stance:
Heel strike 
Loading response (flat foot))
Midstance
Terminal stance (heel off)
Swing:
Preswing (toe off)
Initial Swing

Question 36

1.What happens in heel strike

Answer 36

Lower the forefoot to the
ground
Continue deceleration
(reverse forward swing)
Preserve the longitudinal
arch of the foot

Question 37

2.what happnes in loading response flat floot

Answer 37

Accept weight
Decelerate mass (slow
dorsiflexion)
Stabilize pelvis
Preserve longitudinal
arch of foot

Question 38

3.what happens in midstance

Answer 38

Stabilise knee
Control dorsiflexion
(preserve momentum)
Stabilize pelvis
Preserve longitudinal arch
of foot

Question 39

4.what happens in terminal stance heel off

Answer 39

Accelerate mass
Stabilize pelvis
Preserve arches of
foot; fix forefoot

Question 40

5.what happens in swing phase preswing toe off

Answer 40

Decelerate thigh; prepare
for swing
Accelerate mass
Preserve arches of foot;
fix forefoot

Question 41

6.what happens in swing phase intial twing

Answer 41

Accelerate thigh, vary
cadence
Clear foot

Question 42

7.wat happens in swing phase midswing

Answer 42

Clear foot

Question 43

8.what happens in swing phase terminal swing

Answer 43

Decelerate thigh
Decelerate leg
Position foot
Extend knee to place foot
(control stride) prepare for
contact