Gait Development in the Growing Child

Original Editor - Kapil Narale

Top Contributors - Kapil Narale, Lauren Heydenrych, Naomi O'Reilly, Kim Jackson and Rishika Babburu  

Introduction

The development of gait incorporates components such as maximizing step frequency (cadence), gait symmetry, balance control, and stability, of the gait cycle. The function of these components are facilitated with structural development and neural control of movement.

The development of gait is categorized into six stages: infant stepping, inactive period, supported locomotion, unsupported locomotion, mature similar gait, and mature gait.

Children learn to walk at the age of 1-year. At this stage, walking speed is very slow, and support (supported locomotion) is needed to keep an upright position.

In the developing child, large stride-to-stride variations are seen, including frequent falls, due to the immature control of posture and gait.

Children at the age of 3 years are seen to have a mature gait. Any unsteadiness that can be visually observed develops into a stable gait pattern. However, this does not mean that the gait has been fully matured. Gradual and progressive development in neuromuscular control and locomotor function continue beyond this age. There may be decreased variability in gait after this age.

During the maturation stage, gait speeds increase to mature values. Despite factors influencing gait and gait speed, such as growth and neuromaturation, that are not fully developed, mature gait is said to be reached at the ages of 5-7 years. Until the end of puberty, changes in body structure and sensory motor development occur.

It is seen that healthy infants generally display organization of thoughts and discovery of new movement patterns, including walking. It is believed that some of these patterns are programmed into the genetic code.

Development and Neuroplasticity

The primary action of neonates that represent gait occurs when they react to tactile sensations by producing alternating flexion and extension of their legs and are slowly moved forward on the support surface. This is seen for up to 2-3 months, and then disappears. It reappears around the age of autonomous walking. It is seen that if newborn stepping was trained everyday from birth, then this pattern did not necessarily disappear, but led to an earlier pattern of walking. Infants were able to produce this pattern after 3 months of age, even in different environments and contexts. This reflex could be a factor leading to the ability to walk on two feet, which can be primed with practice. However, stepping could be a phenomenon that can contribute to walking, and the action of walking itself is a skill to be learned.

Despite newborns producing a stepping like pattern with the flexion and extension of their lower limbs, only 70-84% of newborns are able to activate their tactile sensation through producing step-like walking patterns. Infact, newborns can produce various lower limb movement patterns, moving one leg or two legs, or alternating leg movements. These movements originate in utero.

With early stepping there is great variability due to the different possible leg position when the babies are supported in an upright position. Babies have a natural tendency to explore their environment as well. This increases due to the underlying motor and sensory systems, which are better myelinated as the babies move and grow.

A low frequency of stepping movements may be associated with low levels of arousal. However, variability of stepping frequency is high, even when the arousal is 'optimal'. With these observations, it is seen that stepping activity in newborns is not preset or ingrained, but is quite plastic, and develops through time and repetition of practice.

Between the age of 3 and 4 months, infants experience a gradual increase in stepping frequency and percent of continuously alternating steps, due to the infants' increasing strength and weight, thus increasing favorable contact with the support surface. This helps explain the infants' development of leg extensor and hip abductor strength. At this stage, they are able to accept more weight on their legs. At six to seven months of age, the infants are able to produce alternating steps when supported on a moving treadmill.

Infants that are 1-year old, have strong plasticity in behavioural outcome and neuro-muscular activation, for the development of stepping ability. Stepping develops from the association between an infant's maturation and the environment, which refers to the concepts of nature and nurture.

This movement most likely occurs through a combination of active neural input, and passive dynamics, biomechanics of lower limb rotation with the effect of gravity.

Overall, it is seen that meaningful and progressively difficult practice of stepping have a long-term effect on functional neuromotor pathways.

Muscle Activity

The development of the neuromuscular pathways is explained through EMG activity of infants that showed basic rhythmic muscular activity at birth, which would develop into an adult-like stepping pattern by two years of age.

There is also random timing of muscle activation. Subsequent steps taken are not seen to be the same as the previous one in a series of steps, with different muscles firing, frequency, duration, and timing.

With the dynamic system, and variability of movement, the neuromuscular plasticity is an essential component of learning. We are able to find pattens that 'fit' the task, and then we can strengthen it, or prime it, with practice.

Gait at Different Age Levels

Children between 7 and 8 years old are able to achieve independent control of each anatomical segment with walking, thus maintain a stable posture during gait compared to children between 3 and 6 years old. The reduction in gait speed variability as children age could be due to improvements in balance control and posture. It is seen that gait development increases until the age of 8.

It should be noted that different features of stride dynamics develop at different times, hence no two features develop to the same time. There are differences between children of the same age.

Occasionally, the adult gait pattern is seen to show variability between strides. It is seen that the healthy adult locomotor system has a 'memory' where the change from alternating strides shows a gradual 'hidden' temporal structure that is associated with a long range fractal organization. In individuals with neurological disease or the elderly, especially those who experience frequent falls, there is an increase in stride-to-stride variability, and there is altered temporal organization of stride time dynamics.

It is likely that mature locomotion dynamics may be evident when all the contributing components are completely functioning.

Gait speed is also commonly used to assess gait development. It is one of the basic characteristics used to assess and analyze gait parameters. There is high variability when comparing different steps taken in children. Age and body height are two factors which contribute to varying walking speed.

Gait Speed

An individual's gait speed has an influence on their kinematics and kinetics during gait. Thus, from a study by Stansfied et al, 2001, it was shown that walking speed, not age, has the primary influence on gait kinematics and kinetics in growing children. Speed has a similar effect on muscle activity. At very slow speeds, although muscle activity wouldn't bee expected, there is gradual activation noticed in muscle activity due to the increased stability demands.

It is seen that gait speed gradually increases with age and height, up to the age of 15 years, thus it follows that age and body height are some of the determinant factors for walking speed variability. Younger children do have a lower gait speed, while older children have a higher gait speed.

It is seen that walking speed can increase up to the age of 8 years, whereas an enhanced walking speed develops up to the age of 15. However, regardless of age, body height changes display a more uniform increase in walking speed, showing that waling speed is dependent on segment (leg) length and body height.

Children at 1 year of age had the slowest walking speed. It is seen that walking speed increases every year as children age, until the age of 15 years. Standard deviations for 1 and 2 year old age groups were the highest, and were the lowest for the 15 years age group.

The youngest and smallest children displayed the highest variability. The respective phase of motor control learning has a high error rate, a weak reproducibility, and reduced stability. In toddlers, there would be higher variability due to the lack of postural control, efficient integration of afferent information, and supraspinal control.

Stride to Stride Variation

Successive stride-to-stride changes represents the time between one stride and the previous stride. The degree of stride-to-stride variability decreases as healthy children mature.

Stride-to-stride variability is largest in the 4-year old group, a little smaller in the 7-year old group, and the smallest in the 11-year old group. It is seen that there is a highly significant effect of age on variability. The SD (standard deviation) and CV (coefficient of variation) was higher in the 3-4 age group, than the 6-7 age group, and this was higher than the 11-14 age group. The stride-to-stride variability in the 11-14 years age group was similar to that found in healthy young adults. Through observation, even though it may appear that the stride dynamics of children are similar to those of adults, quantitatively it is seen that stride-to-stride control of gait dynamics is not fully matured by the age of 7.

Analyzing stride time dynamics in children may provide insight into the development of neuromuscular control. Stride time dynamics would not be fully matured by the age of 3. The variability of stride time dynamics in younger children can be caused by many factors. It can be caused by a decreased walking speed, and thus decreased postural stability at the lower speeds.

Stride Dynamics and Height

It is seen that after a certain age range, stride length increases linearly with age. However, the relationship between stride length and age becomes constant subsequent to accounting for height or leg length.

It is seen that there is a significant increase in walking speed in the 6-7 year old age group, compared to the 3-4 year old age group. However, relative velocity (velocity/height) was identical in these age groups.

The studies also showed that the average values of stride time and walking velocity were age dependent. These average values were lowest in the 3-4 age group, moderate in the 6-7 age group, and highest in the 11-14 age group.

In addition, it is seen that the temporal structure of gait variability is not fully developed in 7-year old children, whereas in the 11-14 year old age group the stride dynamics are similar to those found in healthy adults.

Interesting Information

Gait patterns in children are similar to those in elderly adults. This may be due to the emergence of primitive reflexes in elderly adults, or reduced balance control. There is also a similarity with the stride dynamics, seen between children, elderly adults, and individuals with neurological impairments.

There are some important differences to note. It is seen that, throughout the lifespan, there is a negative relationship in the fractal scaling index. It is highest in children, lower in adults, and the lowest in elderly adults and those with neurological conditions.

Stride variability is seen to change in a U-shaped fashion, with it being high in children, low in adults, and high in elderly adults and those with neurological conditions.

Resources

Here are two related pages concerning gait and pediatrics:

• Gait Analysis in Cerebral Palsy
• Gait and Lower Limb Observation of the Lower Limb of Paediatrics - (GALLOP)

Here are some videos for a visual, and to better explain gait development in the child:

This is a cute video displaying the gait of a healthy 12 month old child:

This is a presentation on the walking gait development through the four stages of life: Early Childhood, Childhood, Adulthood, and Older Adulthood.