Development of Independent Locomotion

Development of Rolling

Rolling is a prerequisite for supine-sit or supine-stand behavior
1-2 Months
Roll sidelying --> supine
4 Months
Prone --> Supine
4-5 Months
Supine --> Sidelying
6-8 Months
Supine --> Prone
9 Months
Development of segmental
rotation rather than log-rolling.


Development of Prone Progression

Development of Moving from Supine to Standing
-Changes with aging
Infants: roll supine to prone, move to all fours and pull to stand
2-3 years: Partial roll and sit-up pattern
4-5 years: Symmetrical sit-up pattern as seen in adults
prone_progression_2.JPG
Picture from Newell et al.

Figure 5 illustrates the development of the prone progression with the initial posture lying down followed by the emergence of chin up, crawling, creeping and standing. The onset of the fundamental activities of prone progression in infancy is nonlinear. For any infant, the rate of the emergence of an activity and the time it takes to complete the development of the movement form is unique to each respective activity. The presence of a subcomponent of a limb motion in one activity does not guarantee that it will be functional for another activity at the same point in developmental time.There is an ebb and flow to the stability of the coordinative states over developmental time.
Body dimensions are related to the timing of both belly and hands-and-knees onset. Slimmer, smaller babies tend to crawl earlier than chubbier, top heavy, babies. This suggests that crawling may be dependent in part on how much weight infants must support and propel forward.

Development of Sit to Stand

Essential elements/characteristics of normative sit to stand:
1. Generating sufficient joint torque needed to rise (progression)
2. Ensuring stability by moving the center of the mass from one base of support (the chair) to a base of support defined solely by the feet (stability)
3. The ability to modify movement strategies used to achieve these goals depending on environmental constraints such as chair height, the presence of arm rests, and the softness of the chair (adaptation)

VIDEO:
http://www.youtube.com/watch?v=vOYkiqlblgg


Developmental Sequence for Walking: (Table 13.1 in Shumway-cook pg357)

Initial Stage:
1) Difficulty maintaining upright posture
2) Unpredictable loss of balance
3) Rigid, halting leg action
4) Short steps
5) Flat-footed contact
6) Toes turn outward
7) Wide base of support
8) Flexed knee at contact followed by quick leg extension

Elementary Stage:
1) Gradual smooting of pattern
2) Step length increased
3) Heel-toe contact
4) Arms down to sides with limited swing
5) Base of support w/n the lateral dimensions of trunk
6) Out-toeing reduced or eliminated
7) Increased pelvic tilt
8) Apparent vertical lift

Mature stage:
1) Reflexive arm swing
2) Narrow base of support
3) Relaxed, elongated gait
4) Minimal Vertical lift
5) Definite heel-toe contact

Five Important Characteristics of Mature gait:
1. Duration of single limb stance
  • increases from 32% (1 y.o.) to 38% (7 y.o.)
2. Walking velocity
  • increases steadily
3. Cadence
  • decreases steadily
4.Step length
  • lengthens with increasing balance
5.Pelvic span:step width ratio
  • increases until 2.5 yrs, where it stabilizes.

Gait Parameters:

1 year
3 years
7 years
Young Adult Normal Values
Step
Length
(cm)
22
33
48
76.3
Cadence
(steps/min)
176
154
144
112.5
Velocity
(m/s)
.64
.86
1.14
1.46

Head and Trunk Stabilization During Gait


Balance and locomotion are organized according to 2 reference frame
  1. Support surface on which the person stands
  2. Gravitational reference of vertical (use of vision and vestibular information)
When using the support surface to organize balance the child responded from the feet upward. This was accomplished using mainly proprioceptive cues. If stabilization of the head was organized using the gravitational reverence, balance was organized from the head to the feet.

From the time a child can stand until about 6 years of age children organize locomotion in an ascending manner. In this way the child is using the support surface as their frame of reference to control balance. In this type of organization the child is using the en bloc mode of control to control the head, in which the head moves with the trunk. The en bloc mode will reduce the degrees of freedom that the child needs to control during locomotion. Within this mode the stabilization of the hips will be learned first, followed by the shoulders and then the head. At about 7 years of age control of the head changes to an articulated mode, in which the head moves independently of the trunk. At this age, children have mastered control of their head, and descending control of balance during locomotion starts to dominate. Research suggests that this occurs at this age because information specifying where the head is in space becomes more available due to development of equilibrium control centers in the brain. (Assaiante et al, 2005), (Shumway-Cook & Woollacott, pg 360-361)


Fine Lower Extremity Control in Upright Position

Roberson and Halverson hypothesized a temporal sequence of further development of foot locomotion patterns. This sequence begins with walking, which has been discussed in some detail above. The pattern is as follows: walking; running; single-leap, jumping down or bounce-jump, and galloping (in uncertain order, but generally at about 2 to 2.5 years); hopping on dominant foot (seldom before age 3) and then non-dominant foot; and skipping and sideways galloping or sliding. Some children may skip by age 4, however, many do not reach proficiency with this skill until age 7. A rhythmic step-and-hop pattern is the most complex and doesn't appear until well into primary school years.

Appropriate Considerations and Prescription After Impairment

This article written by Michael Babinec OTR/L, ABDA, ATP addresses pediatric mobility from an assessment and prescription standpoint after a child’s developmental mobility has been impaired. The article addresses the aspects of mobility, important considerations, debatable topics, as well as pros and cons between different types of assistive devices. Rather than posting about the developmental stage of mobility control I thought it was beneficial to post this article as a quick reference (4 pages) so that our assessment is multifaceted and comprehensive, before prescription.
http://www.invacare.com.au/index.cfm/3,167,1058/pediatricmobility.pdf



Clinical examination tools provide some indication of ability or extend of control. Here are just a few listed in the Campball book.

The General Movement Assessment (GMA) is conducted with the infant in the supine position and tests the spontaneous movements of preterm and term newborns and young infants. It is seen as an effective and clinically useful tool in infants who might be suffering from early motor control deficit.

The Movement Assessment of Infants (MAI) is used to identify motor dysfunction, changes in the status of motor dysfunction and establishment of an intervention program for infants from birth to 1. It contains items such as self-initiated postures and behaviors identified in milestone schedules.

The Toddler and Infant Motor Evaluation (TIME) is used to monitor change across time or after therapeutic intervention in infants and children 4 months to 3.5 years have taken place. It contains 5 subtests that consist of Mobility, Motor Organization, Stability, Social/Emotional Abilities and an optional Functional Performance subtest. It also contains 3 clinical subtests which are Quality Rating, Atypical Positions, and component Analysis.

Evaluation of Gait Disorders in Children

https://online.epocrates.com/u/2911709/Evaluation+of+gait+disorders+in+children/Differential/Overview
This link provides an overview of what to look for and questions to ask when performing an assessment of a child with gait deviations. It provides both common and uncommon disorders that present in children.

Normal Gait Deviations

  • Toe walking
  • Internal tibial torsion
  • Metatarsus adductus
  • Genu varus
  • Genu valgus
  • Flat feet
  • Crooked toes
If these variations persist and don't resolve with aging or they get worse, cause pain, or limit function then further investigation should be done.

Abnormal Gait Deviations

  • Antalgic gait
    • osteomyelitis, injury to the bottom of the foot, juvenile idiopathic arthritis (JIA)
  • Circumduction gait
    • leg length difference, JIA, CP
  • Spastic gait
    • CP, stroke
  • Ataxic gait
    • Ataxic CP affects the cerebellum, cerebellar ataxia, Friedreich ataxia
  • Trendelenberg gait
    • mm weakness, myopathies, Legge-Calve-Perthes, slipped capital femoral epiphysis, hip dysplasia, JIA, spina bifida, CP
  • Toe-walking gait ("equinus") with absent heel contact
    • CP
  • Stepping gait
    • spina bifida, polio, Charot-Marie-Tooth
  • "Clumsy" gait
    • CP, arthritis, myopathies, metabolic disorders


References

1. Adolph, K. Vereijken, B. (1998) Learning to Crawl. Child Development. 69(5): 1299-1312.

2. Campbell, S.,Palisano, R., Orlin, M., (2012). Physical Therapy for Children (4rd Ed.). P 122-124,
St. Louis: Saunders Elsevier

3. Newell, K. Liu, Y. (2003) A dynamical systems interpretation of epigenetic landscapes for infant motor development. Infant Behavior and Development. 26: 449-472.

4. Shumway-Cook,A., Woollacott, M. (2012). Motor Control: Translating Research into Clinical Practice (4th ed.) P. 362. Philadelphia: Lippincott Williams & Wilkins .

5 .Foster, H., Drummond, P., & Jandial, S.(2011). Evaluation of gait disorders in children. https://online.epocrates.com/noFrame/showPage.do?method=diseases&MonographId=709&ActiveSectionId=11.