Development of mobility control

Question 1

What are stages of muscle tissue development?

Answer 1

Most skeletal muscle developed at birth.
Type 1 and 2 present by 30 weeks gestational age.
# of muscle fibers increases through first year
During growing years muscle fibers increase in length and CSA by addition of sarcomeres

Question 2

What are stages of bone development in kids?

Answer 2

Dipahyses almost ossified at birth
Epiphyses are cartilaginous at birth
Long bone grow at epiphyseal plate
When plate is ossified, bone growth is complete (happens for most bones by age 20)

Question 3

What is the development of the hip in kids?

Answer 3

At birth: acetabulum covers less than 1/2 of femoral head

To age 8: acetabulum depth increases

Question 4

What are conditions that may affect the hip joint?

Answer 4

conditions that affect the normal compressive forces of the hip joint.

Obese: increased likelihood of slipped capital epiphysis or flattened femoral head
Spasticity: at risk for subluxation/dislocation

Question 5

What are essential elements for developing sit to stand?

Answer 5

Progression
Stability
Adaptation

Question 6

What are the 5 attributes of mature gait?

Answer 6

Stability in stance
Sufficient foot clearance in swing
Appropriate pre-positioning of foot for initial contact
Adequate step length
Energy conservation

Question 7

What are prerequisites for gait?

Answer 7

Adequate motor control and CNS maturation
Muscle activation patterns for pelvic stabilization
Adequate ROM and strength
Appropriate bone structure/composition
Intact sensation

Question 8

What is progression for development of gait?

Answer 8

New walkers only have prerequisites.
5 gait attributes develop over time (from age 1 to 4-7 years)
Loss of one of the five attributes results from a loss/failure to achieve the prerequisites

Question 9

What is the neurological control of gait- CPG?

Answer 9

CPG is developed early in prenatal development (early infant kicking and later gait patterns are very similar)

Question 10

What is CPG?

Answer 10

central pattern generator
located in SC
Activated by descending pathways
Descending pathways and sensory input lead to adaptation and modification
Organizes spatiotemporal characteristics of gait

Question 11

When does stepping reflex appear and disappear?

Answer 11

birth to 3 months

3-4 months

Question 12

When does assisted walking and independent walking occur?

Answer 12

8-10 months

9-15 months

Question 13

What does walking look like from birth-9 months?

Answer 13

Supported walking: wide abduction, ER and flexion of hips, bowed legs, everted heels

Question 14

During birth to 9 months how do muscles of gait develop?

Answer 14

Kicking helps develop antigravity strength of hip flexors.
Cephalocaudal development of postural control and extensor muscle strength
Hip extensors are strengthened in prone, creeping, kneeling
Cruising develops hip abductor strength

Question 15

How does gait change with onset of walking (9-15 months)?

Answer 15

Hip extensor strength critical
Wide BOS
Hip abd, flex, ER
Internal tibial torsion
Tibiofemoral varus
Everted heels
Increased hip and knee flexion
Full foot initial contact
Short stride with increased cadence
Relative foot drop during swing
Arms extended for balance
COM at lower thoracic level
Head must be controlled in limits of stability/BOS
Hip strength inadequate to control gravitational forces during gait ("walk by falling")
Co-activation for stability

Question 16

What does gait look like from 18-24 months?

Answer 16

Straight tibiofemoral angle
BOS has decreased
Hip abd ROM is no longer excessive
Increased ant/post movement over planted foot, heel strike by 24 mo
COM descends
Stability improves
Decreased contraction across antagonistic muscle groups

Question 17

How does gait change during 3-3.5 years?

Answer 17

Joint angles mature into adult patterns
Tibiofemoral valgus
Consistent heel strike
COM lowers
Walking velocity normalized for height is similar to adults

Question 18

What are gait patterns for 6-7 years?

Answer 18

Gait patterns are fully mature
Femoral anteversion is largely resolved
Heel position is neutral
Tibiofemoral angle has returned to neutral
COM is at L3 (still a bit higher than in the adult)

Question 19

What are determinants of “mature” walking?

Answer 19

Duration of single  limb stance
Walking velocity
Cadence
Step length
Ratio of pelvic span: ankle spread

Question 20

What are clinical examination tools for gait in children?

Answer 20

General Movement Assessment
Movement Assessment of Infants
Toddler and Motor Evaluation

Question 21

When is a child more likely to have skeletal adaptations?

Answer 21

Skeleton is most vulnerable to deformity in first years of life.
If a child does not experience normal levels of movements, muscle strength, and weight bearing are at risk for osteopenia

Question 22

T/F: bone increases in size before it increases in strength?

Answer 22

true

Question 23

What is hip anteversion in infants?

Answer 23

At birth: 30 degrees

Decreases with normal development

Question 24

What causes anteversion to not be decreased in kids?

Answer 24

If active hip movements are decreased and/or walking is delayed

Question 25

What does excessive anteversion result in?

Answer 25

An in-toed posture and increased W sitting

Question 26

What are causes of antalgic gait, circumduction gait, spastic gait, ataxic gait, Trendelenburg gait, toe-walking gait, stepping gait, and “clumsy” gait?

Answer 26

Antalgic: osteomyelitis, injury to bottom of foot
Circumduction: leg length difference, CP
Spastic: CP, stroke
Ataxic: ataxic CP, cerebellar ataxia
Trendelenburg: muscle weakness, myopathies, hip dysplasia, spina bifida, CP
Toe walking: CP
Stepping: spina bifida
Clumsy: CP, arthritis

Question 27

What are the different types of abnormal gait deviations?

Answer 27

clumsy gait, stepping gait, toe walking gait, Trendelenburg gait, ataxic gait, spastic gait, circumduction gait, antalgic gait