Advanced Gross Motor Skills in Children

Intro

Specific behaviours that indicate typical stages of growth and development are called milestones. Gross motor milestones involve the large muscles and as a guideline occur within a range of time, although every child develops at their own pace. Expectations, cultural beliefs and practices will be displayed during childrearing practices. These variations will provide different experiences and opportunities for each child within and between cultures. This disparity can affect timing for reaching gross motor milestones. Each motor milestone will build on the previous skill acquisition. Infants can not run before walking. They can not walk before standing independently. Standing dependently supersedes independent walking.

Dependent Standing

Around 7 months, children can only stand and/or walk with their hands held. The necessity for external support is due to their underdeveloped balance responses and poor anterior-posterior weightbearing alignment. Gait at this age is marked by a wide base of support with moderate abduction, hip external rotation and pronated feet. The amount of pronation correlates to the amount of abduction and external rotation of the hips. Children during this stage will walk with their hip and knees flexed.

Pull-to Stand

Between 7-8 months old, children begin to pull themselves up in their crib into a standing position. This movement is initiated by utilising the strength of their upper extremities. In this upright position, the child will hold onto the rails and bounce as they interact with their environment. During these early pull to stand experiences, the child has difficulty getting down as they are not adept at using eccentric control of the hip and knees to lower themself. Once tired, they will simply let go and drop down into sitting.

Around 10 months old, children pull themselves up to standing using a low table or sofa. At this stage, they rely mainly on their lower extremities to facilitate the motion with very little effort from the upper extremities. The upper extremities are now used mainly for balance purposes. They move into standing by using the tall-kneeling (knee standing) and half-kneeling postures. They use these same postures to get back down with good control. To transition from tall kneeling to half-kneeling the child goes through the following steps:

• begin in tall-kneeling with a wide base of support
• shifts weight to one side
• elongates trunk on weight shifted side
• unweighted leg moves forward and places foot flat on floor into half-kneeling position
• uses hip and knee extensors to facilitate moving against gravity to standing position

The child will move through the same postures as they transition from standing to floor. With practice, these movements become quick and very controlled.

Cruising

Once the child is able to pull-to-stand, they will play for long periods of time squatting and standing moving back and forth between furniture and floor. The new skill allows the child to squat to play and to pick up toys from the floor and place on the sofa. Squatting becomes both a posture in itself and a transition movement between postures. As the child moves from squat-stand-squat, co-contraction of the ankle musculature occurs enhancing stability.

Around 10 months old, children will begin stepping sideways holding furniture for support. This supported lateral movement is referred to as cruising, With this newfound mobility, the child is able to work their way along the furniture and eventually able to reach other pieces of furniture in an effort to navigate the room. Cruising gait exhibits less hip and knee flexion and better anterior-posterior alignment. Balance is improved during this time as the child is able to lift one supported hand and rotate their body. They may even take 1-2 steps without support from either upper extremity. Cruising helps the child to strengthen their lower extremity musculature specifically the hip abductors/adductors and ankle evertors/invertors. At 10 months of age, the plantar grasp reflex may still be present although considerably diminished. Complete resolution of the reflex is necessary for independent unsupported walking to develop.The child will eventually stand independently letting go of their upper extremity support from furniture or an adult. When this occurs, trunk stability is maintained by a high guard position of the upper extremities.

Independent Ambulation

Between 10-15 months old, children begin to walk independently with the average age of 12 months.

Initial Gait

• upper extremities in a high guard position
• adducted scapulae
• hip and knees flexed
• abduction and external rotation of the hips
• wide base of support
• pronated feet
• no heel strike

Gait Progression 1

• upper extremities in low guard position
• elbows flexed
• hands just above waist and stabilised against the body
• fingers pointing upwards
• shoulders adducted

Gait Progression 2

• upper extremities in shoulder extension and hang at child's side
• reciprocal arm swing
• increasing hip and knee extension
• decreased hip abduction
• decreased external rotation of the hip
• narrowing of base of support
• neutral pronation/supination of the feet
• heel strike, push off

Gait Parameters

Over the next 2-4 years, gait will continue to improve. Gait parameters such as step and stride length and velocity and cadence will change as they grow and mature.

The measurement from heel strike on one foot to heel strike on the opposite foot is referred to as step length. Stride, on the other hand is measured from heel strike on one lower extremity to heel strike on the same extremity. Stride length is roughly twice the step length. Velocity (distance covered over a specified amount of time) is correlated to the length of one's stride or step. Between the ages of 1-3, a child's velocity increases as their stride and step length increase.

During initial independent walking, the child spends very little time in single limb stance due to lack of strength and stability in their hips. This decreased stance time results in a high cadence (the number of steps per minute). As their strength and balance increase over time, the amount of time in single limb stance increases with subsequent decreased cadence.

As they age, children begin to walk with a fast speed, however it is not truly running unless both feet are off the ground at the same time. True running occurs between 3-4 years old.

Stairs

The ability of a toddler to negotiate stairs has many factors with opportunity being a main one. Some children do not have stairs in the home and therefore may not have the chance to practice this milestone. Those who do have stairs are more likely to ascend stairs at a younger age. When ascending stairs, the child needs to use high energy expenditure pulling their body up against gravity. Descending stairs requires the child to maintain their balance on a bent limb during a lengthened swing phase while controlling forward momentum. In addition, descending stairs causes head stability to decrease as the head's centre of mass is displaced due to increased neck flexion.

Initially stair climbing takes the form of both feet landing on each step. Alternating feet with stair climbing does not generally occur until the age of 3.

Upper extremity support changes as stair climbing progresses. Initially the child will be dependent on upper extremity support from a handrail or adult. As they progress, they will not need the support of an adult, however they will use the handrail. Eventually, they will no longer need any upper extremity support.

Resources

• Learning to Stand
• Gross Motor Skills